DeskArtes
Rapid Tools
User Manual
DeskArtes Rapid Tools User Manual
for Version 4
Copyright
Published by DeskArtes Oy, for release 4.0.1, Spring 1997.
© 1997 DeskArtes Oy. All rights reserved. No part of this publication may be reproduced, transmitted, transcribed, stored in a retrieval system, or translated into any language in any form by any means without the written permission of DeskArtes Oy.
DeskArtes Oy reserves the right to revise this publication and to make changes from time to time without the obligation to notify any person of such revisions and changes.
Trade Marks
DeskArtes, Rapid Tools and the DA symbol are trademarks of DeskArtes Oy. Other brand and product names are trademarks and registered trademarks of their respective owners.
Credits
Written by Charles Woodward, André Dolenc, Ismo Mäkelä, Jukka Malmivaara and Maria Nordgren. Produced using Microsoft Word v. 5.0 and Aldus FreeHand 3.1.
Contact Address
DeskArtes Oy
Kalevankatu 3 A
FIN-00100 Helsinki
Finland
Tel. +358–9–644335
Fax +358–9–644330
e-mail DA@deskartes.fi
URL: http://www.deskartes.fi/
Contents
FOREWORD
*About Rapid Tools
*About this Manual
*How To Read This Manual
*Part I: SYSTEM OVERVIEW
*Installing
*Distribution media
*Disk space
*Installation types
*Single account installation
*Starting the system
*Troubleshooting
*The X, GL, and OpenGL Versions
*Getting Started
*Launching
*Window Structure
*Data Flows
*The Mouse
*The Keyboard
*Command Mode : Using the Menus
*Shortcuts
*Executing a Command
*Interrupting a Command
*Edit Modes
*Parameters
*Sticky Parameters and Preferences
*Command Series
*UNDOing
*Files
*Lesson 1: Automatic Demo
*Navigating in the File System
*Loading a File
*Loading STL Files
*Loading Surface Models
*Saving Data onto a File
*DeskArtes Format Model File
*Log Files
*Objects
*Object Types
*Object Hierarchy
*Object Window
*Creating New Objects
*Target Object
*Selecting a Target Object
*Active Objects
*Other Object Window Commands
*Displaying of Objects
*Display accuracy
*Curves
*Faceted Models and Surfaces
*Viewing
*Display Areas
*Viewing Window
*Eye Point
*Shaded vs. Wireframe Modes
*Box Mode
*Dimensions and Transformations
*Units
*Coordinates
*Dimensions
*Transformations
*Grid
*Processing Surface Models
*Viewing Surface Models
*Positioning Surface Models
*Triangulating Surface Models
*Repairing Surface Models
*Processing STL Models
*Viewing STL Models
*Positioning STL Models
*Viewing the Machine Workspace
*Valid STL Models
*Corrupt STL Models
*Repairing STL Models
*For Simulation Purposes
*Processing Sliced Models
*Representation of Sliced Models
*Viewing Sliced Models
*Repairing Sliced Models
*Advanced Applications
*Offsetting: Giving A Thickness To An STL Model
*Splitting STL Models
*Support Generation
*Overview
*Generating Supports
*General Principles
*Support Types
*Choosing the support type
*Support Parameters
*General Parameters
*Web Support Parameters
*Chain Support Parameters
*Point Support Parameters
*Gusset Support Parameters
*Editing Support Parameters
*Slicing supports
*Part II: COMMAND REFERENCE
*File Window
*File Identifiers
*The Directory Pop-Up Menu
*The File Pop-Up Menu
*The Help Directory Pop-Up Menu
*Object Window
*Choosing the Target Object
*Displaying the Target Object
*Object Window Pop-Up Menu
*Settings Window
*BACKUP
*UNDO
*TEACH
*EXEC
*REPS
*SHARP/SMOOTH
*AREA
*DRAW
*REFR
*MODE
*Display Parameters
*CLIP
*GRID
*Eye Directions
*Vector Color Buttons
*SYSTEM
*Show Files
*Show Objects
*Show Settings
*Save Layout
*Set Colors
*Mouse Control
*Backup Control
*Reset
*Quit
*OBJECT
*New
*Copy
*Delete
*Cut and Paste
*Split
*Merge
*Rename
*Change Type
*Active/Passive
*SELECT
*Object: Pick
*Object: Next / Prev
*Object: Surface
*Object: By Name
*Show: Next and Prev
*Collect: Actives
*Collect: Display
*Collect: Selection
*File: Write
*VIEW
*Panning, Zooming and Viewing
*Object: Draw
*Object: Fit
*Object: Blink
*All: Draw
*All: Fit
*All: Erase
*View: Pan
*View: Zoom
*View: Eye Point
*View: Move Light
*View: Rotate View
*View: Clipping
*Preferences
*RENDER
*GL Window: Shaded View
*GL Window: Wireframe
*GL Window Operation and Commands
*PreView: Shaded View
*PreView: Hidden Lines
*PreView: Redraw Image
*PreView: Store Image
*PreView: Done
*Preferences
*TRANSF
*General Functionality and Mouse Buttons
*Object: Move
*Object: Scale
*Object: Rotate
*Object: Mirror
*Object: Repeat
*Object: Move Positive
*Object: Move Center
*Object: Rotate on Facet
*Object: Scale Inches/Mm
*Fix Point: Set
*DIMENS
*Tools: Calculator
*Text: Input
*Text: Edit
*Object: Bounding Box
*Object: Centerpoint
*Object: Extents
*Slice:
Dimensions *Faceted: Area
*Faceted: Volume
*Faceted: Dimension
*Surface: Point
*DESIGN
*Curve: Input
*Curve: Edit
*Curve: Polygon
*Curve: Arc
*Curve: Circle
*Curve: Offset
*Surface: Primitive
*Surface: Extrude
*Surface: Rotate
*Surface: Build
*Tolerance
*FACETOR
*Check: Looping Trims
*Check: Touching Trims
*Check: Multiple Trims
*Check: Multiple Surfaces
*Check: Everything
*Surface: Verify
*Surface: Triangulate
*Surface: Reduce Trims
*Surface: Invert Cut
*EDITOR
*Faceted: Verify
*Faceted: Repair
*Object: Merge
*Object: Separate
*Object: Parting Lines
*Object: Show Normals
*Object: Cutoff
*Triangle: Get
*Triangle: Add
*Triangle: Delete
*Triangle: Remove Area
*Triangle: Fill Gap
*TOOLS
*Faceted: Chop
*Faceted: Boolean
*Faceted: Reduce
*Faceted:
Refine *Faceted: Offset
*Curves: Cut Two
*Curves: Join Two
*Curves: Cut All
*Curves: Join All
*SLICES
*Slices: Generate
*Slices: Generate All
*Slices: Close Gaps
*Slices: Change Dir
*Slices: Edit Slice
*Slices: Scan Slices
*Slices: Find Gap
*Slices: Preferences
*SUPPORTS
*Supports: Generate
*Supports: Parameters
*Supports: External
*Part III: APPENDICES
*Multi-user installation
*Installation Troubleshooting
*Installation tips for system administrators
*
DeskArtes Rapid Tools provides you with all the necessary commands to triangulate, verify and correct surface models for rapid prototyping (RP). You may process surface models, triangulate them, cut triangulated models in parts, offset them, generate supports, and slice into contours for the RP machine.
You may pick individual surfaces or triangles, delete them, and add new triangles when required. You can even change the position of individual triangle vertices. Various general purpose command are available, such as transformations, viewing and shading.
Results of each command are displayed to you as the commands are executed, and possible problem areas are separated as their own elements in the DeskArtes work space.
Part I
explains the structure of the system, how it operates, and how you can accomplish certain tasks. It begins with software installation instructions and it continues with Chapters on how to load files into the system, how to view them, and how to analyze their dimensions and change their position.It also has lessons and exercises in using Rapid Tools. While reading the text, you may carry out the lessons and preferably the exercises too before trying out the features with one of your own models. You can also practice with the examples that come with the system.
Part II is a Reference Manual which you may consult to find additional information about a topic, e.g. a specific menu. Use it as reference whenever you wish to know more about the parameters and other information of how each command works.
Part III contains Appendices.
DeskArtes Rapid Tools uses several batch programs to carry out certain tasks which you can also use stand-alone. They are documented in a separate manual called The Utilities Manual.
DeskArtes Rapid Tools serves several application areas. You should choose an application that best suits your needs, and then follow the instructions in the next sections.
• Rapid Prototyping is the main application area of Rapid Tools.
• In Data Transfer applications, the purpose is to use Rapid Tools to convert or manipulate IGES, VDAFS, or STL files so they can be used by another CAD package which cannot otherwise handle the original data file.
• As a Front-end to Simulation Packages, Rapid Tools is used in a similar way as Rapid Prototyping. Many simulation packages accept as input STL files, but if they may require repairing or modification before they can be used. In addition, it may be necessary to use Rapid Tools to generate the STL file from a surface model.
Regardless of your application, you should read the following Chapters in Part I:
• Getting Started explains how to launch the system, the structure of the various windows and what they are used for, how the system usually reacts to the mouse, and so forth. In short, it introduces the basic concepts used throughout the entire manual.
• Files explains how to bring data into the system.
• Objects explains how the data brought into the system is structured.
• Viewing explains how to view the data on the Graphics Window.
You may wish to read quickly through these Chapters but it is important that you pay close attention to sections Window Structure in Getting Started and up to Loading a File in Files. You may then proceed to the lessons. In that case, however you may need to turn back a few pages to understand what is really happening.
Rapid Prototyping Applications
If you are mostly interested in processing surface models, read the section Loading Surface Models in Files and the Chapter Processing Surface Models.
If you are mainly interested in handling STL models, read the section on Loading STL Models in Files and the Chapter Processing STL Models. There are dedicated Chapters for advanced applications and support generation.
Depending on the process you are using, some features are curiosity only. For instance, if you are using a process that does not require support structures, the Chapter dealing with that topic is not relevant to you.
If you use a process that cannot receive as input slices but is restricted to STL models, then you cannot benefit significantly from the features related to sliced models, and the Chapters about curves and slices are of less significance.
If you are not interested in data transfer application, the Section on how to write IGES files is not of much use to you.
Data Transfer Applications
The Chapter Files contains most of the information you need. Also the Chapter Processing Surface Models explains the
FACETOR menu which allows you to analyze a surface model. That Chapter also contains examples on how to edit the trimming curves.Part II contains information about writing files, and you will also benefit from reading about
vda2igs and igs2vda in the Batch Tools User Manuals.
Simulation Applications
The Chapter Processing STL Models contains a dedicated Section for those who use Rapid Tools as a front-end to simulation packages.
DeskArtes Rapid Tools is normally delivered on either a 4mm DAT/DDS or a 1/4 inch QIC-150 tape depending on which one the client prefers. In both cases the tape is written with the UNIX tar
command. The whole software is in one big tar file.
To install the software, you need about 50 MB of free disk space. The exact size of the distribution varies between different platforms.
There are two different types of installations: single account installation and multi user installation. The single account installation is applicable in most cases and only it is explained here. For information about the multi user installation, see Part III under the heading Multi user installation.
In the single account installation a user account is created for the software and the whole installation is loaded into the home directory of that user account. DeskArtes Rapid Tools is then always run with that user account.
The idea behind the single account installation is that by using a dedicated user account for DeskArtes Rapid Tools, we are not destroying the settings of any existing user account. Also when evaluating the software it is easier to destroy the installation if you decide not to purchase, because the whole distribution is under one directory.
To make a DeskArtes single account installation follow the next example. In this example the installation directory is chosen as
/usr/people/dahome and the program user account is named as da. Login as
Find a file system with enough space for the installation with the command:
df
Select a directory from that file system and make it the current directory.
cd /usr/people
Create a new directory for the installation.mkdir dahome
Read the DeskArtes installation tape into the dahome directory:
cd dahome
tar
xv
Start the DeskArtes installation program with the command:./dainstall
Dainstall first asks the name of the customer. This is the text which will be shown in the title bar of the DeskArtes main window. You can choose any name you like:
Donald & Co. Design Office Ltd.
The second question is about the installation type which is
1
for the single account installation.
Then the user name is asked. You can give any name you want, the default is
da
Dainstall then asks if you want to create the new account. Answer
y
for yes.
Then the path of the installation directory (dahome) is printed and dainstall asks if it's correct. Answer
y
for yes, except if you know for sure that the installation directory is better accessible from network with some other path.
Logout and exit the windowing system.
To start using DeskArtes, log back in with the user account you chose above (da).
Once you have installed the system, try launching it using the command
rt, rapids, or rapidsgl.
In case of any problems with the installation or licensing, they should appear already at this point. If you had installation problems the software probably doesn't start up at all. Please check that you followed the above start-up steps as explained. In case of license problems you should be able to run the "summary" demo, but the other demos won't work. In such case, please consult your local DeskArtes distributor for advice.
Further information can be obtained in the Part III under the heading Installation Troubleshooting.
The X, GL, and OpenGL Versions
All platforms are delivered with the so-called X version. This version does not take advantage of any special graphics hardware your computer may have.
On SGI and HP machines, the software is also distributed with implementations that will use special graphics hardware that greatly improves the performance of viewing 3D objects. For instance, real-time shading is possible with this implementation. These are the so-called GL and OpenGL version.
When you launch the system, the version that suits you best is chosen. If for any reason you wish to use the X version on a GL-based platform, simply add the option
-X to the command line.Some of the differences between both versions are as follows:
• The X version has a box mode in the Settings Window, whereas the GL version has shaded mode.
• The X version has a PREVIEW menu for software-generated shaded images, hidden lines, and so on. This menu does not exist in the GL menu.
The Manual will contain specific notes when a feature is particular to a given version.
If you are using the GL or OpenGL version, just remember to
• skip all
• use the middle mouse button for the zooming and panning operations.
After installing the software, you get DeskArtes Rapid Tools launched under Unix with the start-up command
rapids.
Once launched, the user interface windows should look roughly as shown below:
The windows and their meanings are:
• The Graphics Window, the area that takes up most of the screen, is used for graphical operations such as entering point data and displaying objects.
• The Object Window, to the left, shows which object is currently selected for the next command. The object in question is darkened, and is called the target object.
• The Settings Window, to the right, contains variables that control the display environment, color of your drawing and background, etc. Here you may control things like eye point and select the input type for your curves, among other things.
• The File Window, in the middle, shows the model directories and the files they include. It also includes a number of commands used to control files and directories. These are operations like creating, reading, and writing.
• The Menu Bar, at the top, holds most of the DeskArtes commands. Each of the items in the menu bar holds a menu of commands.
• The Message Lines, below the menu bar, display all the text messages, such as system status, information on the target object, answers to geometric queries, prompts, short help messages, and error messages.
Other windows may appear as you operate the system:
• Some commands require parameters which are entered using Dialog Boxes (or Parameter Windows).
• In edit modes, Icon Windows (or Toolboxes) will pop-up.
• The user interface Color Window is available for selecting the colors for the user interface and display. It appears with the command
The following figure illustrates how data flows between the three main windows:
The Chapters in Part I follow the data flow. When data is loaded via the File Window, it is "stored" in the Objects Window. The viewing commands place the objects on the Graphics Window so you can inspect them.
In many cases, e.g., when moving an object or a point to a new location, you are requested to define the actions interactively with the mouse.
The action may depend on which mouse button you press when starting the action. For instance, when moving an object, the left mouse button moves freely in all directions, while the middle button would move in one direction only.
There is also a difference between "clicking" and "pressing" a mouse button. Clicking means pushing on the mouse button, and immediately releasing it again. Pressing means pushing the mouse button down, and holding it down until the interaction is finished.
In most cases, DeskArtes doesn't mind if you click or press. For instance, to move an object, you may either
1) press, move, and release when you done, or
2) first click, then move, and click again when ready.
As an exception, however, zooming and panning in the GL windows must be done in the first way (by pressing).
The mouse buttons will behave according to the window were it is currently placed. In command mode, they behave as follows:
When placed onÉ |
LEFT Button |
MIDDLE button |
RIGHT button |
Menu Bar |
Menu is shown when pressed on one of the titles. |
||
Graphics Window |
Depends on the Mouse Control settings. |
||
Objects Window |
Selects a target object in one of the lists. |
A pop-up menu appears with object-related commands. It is the same as the OBJECT menu found in the Menu Bar. |
|
Settings Window |
Changes the settings accordingly. |
||
File Window |
Selects a file from one of the lists or edits the current path. |
When pressed on a list, a pop-up menu appears, one for each list. |
The mouse buttons will take different meanings on the Graphics Window when certain commands are used, e.g. when you enter edit mode. The Message Lines will give a short description of their meanings when such commands are used.
You may also change the meanings of the mouse buttons when it is over the Graphics Window using the command
SYSTEMÞ Mouse Control.
The keyboard is used to fill in entries in dialog boxes to supply parameters in the form of numerical values and text. An example of text is a file name. A numerical value may be, for instance, a tolerance to be used in some task.
Another very important function is to allow the user to use hot keys, i.e. shortcuts to frequently used commands in menus. Most hot keys are active when the cursor is on the Graphics Window, but some are also active when dialog boxes pop-up.
Command Mode : Using the Menus
DeskArtes is controlled in two modes. The default mode is called command mode. The principles of operation in command mode are explained in the sequel. Some commands place the system in edit mode, which will be discussed later.
The DeskArtes commands are grouped into menus. There are two kinds of menus: pop-up menus (in the Object, File and Settings Windows), and pull-down menus (located in the top Menu Bar).
Pop-up menus are normally invisible: they appear when the MIDDLE mouse button is pressed in an appropriate area. For example, the File Window has three pop-up menus—one menu for each sub-window ("field")—and the Object Window has one. The Object Window's pop-up menu appears when the MIDDLE mouse button is pressed with the cursor within the Object Window.
Pull-down menus are found in the top menu bar. Each of the menus contain commands related to a specific subject.
To select a command from a pull-down menu, point the cursor at the desired menu title and hold down the left mouse button. Still holding the button down, drag the cursor to the desired command. Execute the command by releasing the mouse button.
Some things are controlled with buttons. In particular, the settings window contains buttons that control very generally the way DeskArtes works: whether to use a grid, how to display the objects, when to undo commands, and so on.
Finally, some "commands" are executed directly by pointing and clicking. In particular, a target object can be selected by pointing and clicking at the desired item in the object window.
When the cursor is on the Graphics Window, some commands may be entered using a single letter shortcut, without going via the menus. This is a useful way of getting at often used or repeated commands.
For example, the commands in the
VIEW menu are used so often that their shortcuts should be learned as quickly as possible. The available shortcuts are shown within brackets [ ] next to each menu item (such as Quit [q] in the above illustration).Some shortcuts are also available when a dialog box is displayed. They are explained in the section Parameters below.
Shortcuts makes working with DeskArtes much more efficient, as you don't have to move the mouse for each command.
When a command has been given in one of the ways described above, the system displays a "busy" message and the cursor turns into a watch. This indicates that execution of the command has been started.
The execution of the command may contain various phases, such as asking for parameters, editing of a curve, changing colors, etc.
To show that it is ready to accept a new command, DeskArtes displays "ready" in the message lines and the cursor turns into an arrow. Before that happens, the system is still in the middle of the previous command, and attempting to enter a new one is denied by the system.
Do not try to enter new commands during the execution; usually, it wouldn't even work, but it might only get the system confused.
Some display commands, such as drawing a wire-frame or shaded pictures, can be interrupted by pressing the
ESC key, or alternatively Ctrl-C, with the cursor in the window where the program is executing. This can be useful if the execution seems to take too long and you wish to continue with other commands instead.Other commands pop-up a dialog box with a progress bar and a
CANCEL button. Pressing that button will eventually abort the operation but it may take a while.Most commands cannot be interrupted. If you have started a command or an editing function, and interrupting doesn’t seem to work, finish the command before trying to do something else. You can always undo a command after it has been completed.
Commands which deal directly with individual points, e.g., curve control points switch the system to edit mode.
None of the command mode commands are available in the edit modes. The object window and the menu buttons disappear, and small pictures called icons appear instead.
The icons graphically describe what each command does. To execute an editing function, click on an icon with the left mouse button. Alternatively, click at the function key which is displayed in the upper left hand corner of each icon.
When using function keys in edit mode, note that lowercase and UPPERCASE letters have different meanings. For instance, in the command
DESIGNÞ CURVE Edit, function c produces a rounded corner near the active point, while C makes the curve closed.A brief help text of each icon appears in the message lines if you click on the icon with the middle mouse button.
To get back to command mode, click on the "Smile" icon. That way any changes you made in the edit mode will be accepted. If you for some reason wish to undo all your changes, you may click on the "Sorry" icon instead.
Many commands require parameters. A parameter is a piece of specific information a command needs to know. Parameters are entered in the dialog boxes, which pop up whenever needed.
There are three kinds of parameters:
• Numeric parameters (e.g., 1.0, 5, .334)
• Text parameters (e.g., a name)
• Alternative parameters (e.g., yes/no)
Each of the parameters has a default value, which is already selected when the dialog box appears.
Numeric or text parameters may be changed by clicking at the old value with the left mouse button and entering the new value. They can also be changed just partially by double-clicking at the area you want to change and typing in the new data. For alternative parameters, merely click at the appropriate alternative to select it.
You may enter real number parameters with or without the integer or fractional part. For example, a zero can be entered as 0, 0.0, 0., or .0 (but not just as ".").
For text parameters, use only digits 0–9 and letters a–z, A–Z. The space character is automatically converted to an underscore. Avoid using special characters such as "; > %
", etc., as they could cause confusion with the UNIX system when used in file names.You may delete a character by using the
del or BackSpace key.To move from one line to another, you may use the tabulator (
®|) key instead of pointing with the mouse. This is especially useful when entering sequences of numeric coordinate data.When all parameters have been entered, close the dialog box by clicking on the
OK button at the bottom of the box, or by entering the Return (¿) key.If you while entering the parameters decide you don't want to perform the command after all, close the dialog box by clicking on the
CANCEL button instead.
Sticky Parameters and Preferences
Many parameters in dialog boxes are "sticky", i.e., once you change them, they stay that way until you change them again.
Some dialog boxes allow you to save the parameters. When you hit the
SAVE button, they will be used as default values the next time you launch the system. These parameters are stored in what is called the preference database.If you have changed the parameters during the course of a session and you wish to see or restore the values from the preference database, then you can hit the
RESTORE button.Each account has its own database stored in the file
.DA_Prefs in the home directory of the account. Two users cannot use the same account and choose different preferences for the parameters.
A command series may be used to "teach" the system a series of commands (a "lesson") that can afterwards be automatically repeated any number of times.
The command
SettingsÞ TEACH stores the next commands and editing operations into a designated file. To end the lesson, click at SettingsÞ TEACH again. Afterwards, the lesson may be automatically executed any given number of times, with the SettingsÞ EXEC command.Use
TEACH and EXEC whenever you notice the modeling task would require you to perform the same things over and over again.For instance, the following figure was produced by first teaching the system to copy, rotate and scale a single (topmost) curve. The rest of the curves were produced by repeating the command series some 30 times over.
All the commands which affect the geometry are
UNDOable. You may undo a command by clicking at the corresponding button in the Settings Window, at right.Having the
UNDO function available stores the complete model to disk before each command. The location of this backup can be chosen using the Backup Control in the SYSTEM menu.It is recommended that it be in the directory /tmp in the local disk. Otherwise, it is placed in the current selected directory. With large models, and especially when operating over a network, this may be much too slow to be practical.
To disable the
UNDO function, click at the BACKUP button at the top right corner.When you start the system, the File Window automatically shows up. Initially, the currently selected directory is the one you launched DeskArtes Rapid Tools from. This Window has the following structure.
The Directory List is used to navigate in the file system of your computer. Although the files listed may not all be directories, all operations or commands used in this list can only be carried out successfully if the selected entry is a directory.
In the File List you will find the files in the current directory. A file can only be loaded if it is listed there.
The Help Directory is used mainly to look at an alternative directory. Files can be copied from the Help Directory to the current directory, and vice-versa. Other operations are possible and these are explained in detail in Part II of this Manual.
Clicking on an entry with the LEFT mouse button lists the files in that directory in the File List. As you can see in the figure above, the current directory is highlighted and it is "
/m/runski/ver/da32/CXBASE/DA_rapids".The Path Line is available to quickly change from one directory to another. You can edit that line, and when you press the ENTER or RET key, the files in that path are listed in the Directory List, and you must then select the appropriate entry.
Each of the three lists has its own set of commands and they are shown when you move the cursor over one of the lists and click the MIDDLE mouse button. A detailed description of each command is available in Part II of this Manual. In this Part, only the most frequently used operations are described.
At this point, you should have enough information to see through the automatic demo. It requires that you launch the system, use a couple of commands in the File Window, press the
EXEC button in the Settings Window, and press the OK button in several dialog boxes.The demo will give you a general overview of the specialized rapid prototyping functionality. The demonstration runs through various features of DeskArtes Rapid Tools, actually computing the different steps as it goes. The length of the demo is some 10-20 minutes, depending on the hardware.
Once the demo is loaded, all that is required from you is to click on the
OK buttons as they come along. When the demonstration completes, the system will exit automatically.At this point, we will assume that the software has already been installed, and you have a window with a shell prompt from which you can launch Rapid Tools.
To start the demonstration, please follow the following simple steps:
Launch Rapid Tools by giving the command
Once the user interface appears, move the cursor to the Directory List in the File Window.
Click the MIDDLE mouse button and choose the command
CHANGE DIR:CXBASE. Use the LEFT mouse button to select the directory
RT_demo. Click on it, but do not double-click! Click at the
OK button in the File Window. Click at the
EXEC button in the Settings Window (at top right). Accept the default parameter values in the dialog box that appears, and click at
OK. The demo now starts.It is possible to run through only parts of the demo at a time. For this, after clicking the EXEC button you may select one of the following options for the file name:
• facetor - how to read and repair IGES surfaces
• editor - interactive / automatic STL repair
• boolean - cutting parts, adding new features
• offset - shells, hollow models, slicing
• supports - display of support structures
• summary - overview of all modules
Troubleshooting
You cannot run the demo to completion if one of the following problems are encountered:
• Lack of write permissions in the demo directory. To check your permissions, use the command
• You do not have a license to run one of the modules that is used during the demo.
There are several ways to change from one directory to another. In order to move down to a subdirectory, simply double-click the corresponding entry. This will cause the entries in the File List to move to the Directory List. You then choose a new sub-directory. Double clicking works this way in both the Directory and File Lists.
If you wish to move up, double-click on the first entry in the Directory List. This entry is always two dots, i.e.
"..".You can also edit the Path Line as explained earlier or you can use the commands in the Directory pop-up menu. Press the MIDDLE mouse button and choose
CHANGE DIR:UP or DOWN to move up or down the file systems' directory tree, respectively.Even more alternatives exists, but you should consult Part II of this Manual for further information.
A special directory is created when you install Rapid Tools. It contains, for instance, the automatic demo and the CAD models that are used in lessons and exercises. It is referred to in this Manual as
CXBASE and you can find it automatically by choosing the corresponding entry in the Directory pop-up menu.
To read in a data file into DeskArtes Rapid Tools, you may double-click on its name in the File List of the File Window. The input file format may be either IGES or VDA-FS (for surface models), DXF or STL (for faceted models), or CLI, SLI and SLC (for sliced models).
For Rapid Tools to take the right action when you double click it, the file's name must have the correct prefix or suffix. If it does not, you must rename the file, e.g. using the
RENAME command in the pop-up menu in the File List.Loading a file creates new objects. The way Rapid Tools structures the data that is loaded is explained in the Chapter Objects. For now, we will explain how different file formats should be loaded.
A file is recognized as being an STL file if its name ends with ".
stl". Simply double click on the file's name.You may have trouble when STL files are corrupt. Frequently, they are transferred from one location to another using not-so-reliable medias such as diskettes or unreliable telecommunication protocols.
Unlike most other rapid prototyping packages, Rapid Tools can represent surface models internally. Consequently, the model can be analyzed and repaired before a triangulation or slicing is done. Additionally, the repaired model can be written onto a new data file for further processing by another CAD package.
The surface models that can be used internally are a subset of the ones found in IGES and VDAFS files. When a surface–or any other geometry– cannot be represented exactly in Rapid Tools, an approximation takes place. You can control the accuracy of the approximations by supplying a tolerance.
For any application, this tolerance is the most important parameter to consider.
Lesson 2: The Approximation Tolerance
The purpose of this lesson is to show you graphically the effect this tolerance has when reading surface models. An artificially built CAD model will be loaded and you should simply inspect the drawing on your screen.
Launch Rapid Tools by giving the command
Once the user interface appears, move the cursor to the Directory List in the File Window.
Click the MIDDLE mouse button and choose the command CHANGE DIR:CXBASE.
Use the LEFT mouse button to select the directory
RT_training.
Double-click on the file named geom_cylinders that appears in the File List.The circles you see are cylinders viewed from the top. The red and yellow geometries were loaded from the same IGES file but with different tolerances. The red and yellow data sets were loaded with approximation tolerances equal to 1mm and 0.01mm, respectively.
Be warned that visual inspection is not always the best way to assert the accuracy of a surface model due to display artifacts.
Loading IGES files
Rapid Tools recognizes an IGES file when the file's name ends with ".
igs". When you double click on an IGES file, the following dialog box is shown:As mentioned earlier, the approximation tolerance is used when a geometrical entity cannot be represented exactly in Rapid Tools. This includes conic and circular arcs, high degree curves and surfaces, offset surfaces, and true rational curves and surfaces.
It applies also when trimming curves must also be computed either because they are not present or because you have requested it by specifying
YES in the associated toggle. You may need to recompute them when the IGES file contains incorrect data. Please read the guidelines in the following sections for more information.The trim curve tolerance is used for data reduction. This value should be kept small. Further data reduction can be done after the model is loaded using the command
FACETORÞ Reduce Trims.The toggle force tangent continuity should only be used if you know the input data is already tanget continuous, and that must be preserved.
If you know there is data in the file but nothing is loaded, it may be because all the entities are orphans, i.e. entities used by a parent that does not exits. In this case, you can try again with read incomplete data set to
YES.CAD data in IGES files can be expressed in about 12 different units. You may choose one of the three shown in the figure above. If you change the units, make sure the approximation tolerance is expressed in the corresponding units. The approximation tolerance is applied after the model is scaled, if necessary, to the desired units.
You should read the guidelines in the following sections for more information on how to use these parameters.
By default, once the model is loaded, you get two elements in the Object List. The first element contains the surfaces and the second element contains the 3D curves. If one of these elements is not present, it is because the corresponding geometrical entities were not found or not converted from the input file. For instance, some IGES files do not contain surfaces, but only curves.
IGES files from HP/SolidDesigner containing Subfigures are an exception. In some cases, several elements are created. Each element corresponds to a subtree in the model hierarchy originally stored in SolidDesigner.
Loading VDAFS files
Rapid Tools recognizes a VDAFS file when the file's name ends with ".
vda". When you double click on a VDAFS file, the following dialog box is shown:As mentioned earlier, the approximation tolerance is used when a geometrical entity cannot be represented exactly in Rapid Tools, i.e. curves and surfaces of degree higher than 3.
The trim curve tolerance is used for data reduction. This value should be kept small. Further data reduction can be done after the model is loaded using the command
FACETORÞ Reduce Trims.The toggle force tangent continuity should only be used if you know the input data is already tangent continuous, and that property must be preserved.
CAD data in VDAFS files can only be expressed in millimeters.
By default, once the file is loaded, two elements are created. The first element will contain the surfaces, and the second element will contain the 3D curves. If the file contains
SETs, you may prefer to store each set in a separate element. In this case, each element will contain the surfaces and the curves listed in the given set.You should read the guidelines in the following sections for more information on how to use these parameters.
Guidelines for Rapid Prototyping Applications
The issues you must keep in mind are the following:
Accuracy. Two approximations may be needed when processing surface models, one when loading the file and certainly another one when the triangulation is generated. Eventually, two tolerances will be needed. Their sum should be less or equal to the accuracy you wish for the final part.
Trimming curves. Some CAD systems do not include correct boundary information. Once you load the file, check the surface boundaries against the 3D curves. If they are not correct, you can load again the file but this time request a re-computation of the trimming curves. Usually this is required when the file was generated by CATIA. If this procedure fails, then you must edit the offending trimming curves using the
Some trimming curves are delivered with far too many points. Display performance if affected by the complexity of the trimming curves, and each segment in the trimming curve results in a triangle in the shaded image or STL file. In these cases, you may want to set the trim curve tolerance to a larger value.
VDAFS files. It is not possible yet to recompute trimming curves when the input file is in VDAFS form. However, it may be converted to IGES using the
FILEÞ CONVERT command from the File List in the File Window.The toggle for preserving tangent continuity is of little or no value for rapid prototyping, i.e. if the sole application is to generate an STL file. The incomplete data which IGES files may contain is usually of no value either, so you should not load it into the system.
Guidelines for Data Transfer Applications
A data transfer application is one in which a new data file will be generated. The purpose may be to:
Simplify the IGES file. IGES files may contain a multitude of different entities. Some of these may be supported by Rapid Tools but not supported by some other CAD system you may have. The IGES files generated by Rapid Tools contain only simple entities and they can be tailored to meet the requirements of specific CAD systems.
Convert between IGES and VDAFS. For this purpose, the file does not necessarily need to be loaded. Such conversions can be carried out using the
FILEÞ CONVERT command from the File List in the File Window. In this way, fewer approximations take place.Analyze and repair the file. The tools in the
FACETOR menu may be used for this purpose, in addition to the ability to recompute the trimming curves.The guidelines for rapid prototyping applications apply to these cases as well. In addition, you must consider the following:
Tangent continuity. Some applications require very smooth surfaces. If, for instance, the model is to be visualized using high quality ray-tracing techniques with mirror effects, continuous patterns cannot be generated if the surfaces are not tangent continuous. Other applications include manufacturing and analysis. Using this option will increase the number of patches loaded into the system.
Incomplete data in IGES files. Some entities may be tagged as having a parent. In IGES terminology, an entity with a parent should only exist in the receiving end if the parent is also included in the file. Therefore, entities without a parent-"orphans"-are not loaded unless otherwise stated. If orphans are loaded, it is not possible to distinguish them in Rapid Tools.
There are three different ways to invoke a save, or write, operation:
• You can select the
• You can use the shortcut from the Graphics Window, and simply hit the
w-key with the cursor on that window.• You can select the
FILEÞ Write command from the File List pop-up menu in the File Window.Before you save data onto a file, you must determine what you wish to save, where it should be stored, and in which format.
Let us address the where first. The data will be stored in the current selected directory. Therefore, you must change directories as explained earlier if you wish to save the data elsewhere. If the file already exists, a confirmation will be requested.
What is stored in the file depends on the file format you select. Except when storing data in DeskArtes Rapid Tools native file format, only the target objet is stored. If you wish to store more than one element using an external file format, you must first merge or collect the objects into one separate element, and then save that element onto the file.
Pictures are another exception in that data is taken directly from the screen–not the target object–and placed onto the file.
Please read the Chapter Objects and the Section describing the
FileÞ Write command in detail in Part II of this manual, the Reference Manual.
Reading in VDA or IGES files may be quite time consuming. For this reason, just after reading the data transfer file you should write it into the DeskArtes special format file, which is much faster to read in afterwards.
To write a DeskArtes model file, use command
FILEÞ WRITE in the File Window, or alternatively the menu command SELECTÞ File:Write, and select "model" from the parameter options.
Several commands report results in a log file, telling how many errors there were, if any, and where. The log files are created under the current selected directory when the command was invoked, and each command has a separate log file.
Some commands, such as the
Verify commands, the log file is automatically displayed on screen once the command is ready. Otherwise the log file may be viewed in the selected working directory with the UNIX "more" command or other text editors. The choice of editors is displayed as you double-click at the log file name in the File Window.Notice that if several users are working with DeskArtes Rapid Tools in the same directory it may create confusion with the log files, if the users are executing the same command at the same time. Please try to avoid this situation by working in different directories with different models/users.
Rapid Tools can handle both curves, surfaces, and faceted models. (Technically, faceted models are surface models consisting of bounded planes.)
Curves may be two- or three-dimensional and may take several representations.
Surfaces are created when IGES or VDAFS files, and they may be trimmed or untrimmed.
Faceted models are created when reading STL or DXF files, when surfaces are triangulated, or when surfaces are created using the
DESIGN menu.Attribute objects are objects that have no function alone, but only when they are associated to another object (surface). Currently, the only attribute objects are trim curves .
Each of these object types is explained in detail in the following sections.
Geometric information is represented as a four-level hierarchy, where each level may contain certain types of objects only.
1. The top level is called the root. It contains all the geometry contained in the system at the time.
2. The root is divided into elements. Each element has a user-given name.
Typically, an element contains all the geometry of a given type associated to a given model. For instance, one element may contain all the surface information associated to a model and another element may contain a triangulation of that same surface.
3. The elements are divided into objects. Each object has a name which depents on the object type. For example, triangle elements consist of faceted-objects.
4. The lowest level of the object hierarchy contains the primitive objects, namely, individual curves and polygons (or facets).
The object hierarchy may be accessed through the object window. It contains three fields for showing the objects of different levels:
• The top field contains all the elements;
• The middle field contains all the objects in the chosen element;
• The bottom field shows the primitives of the selected object.
The object window contains a pop-up menu (shown in the illustration) with general commands that manipulate the objects. Exactly the same commands can also be found in the
OBJECT and VIEW menus.
Many commands automatically create new objects and elements. You can create new elements and objects too, and re-organize them in the Objects Window.
If you must create a new element, use the command Objects
Þ NEW from the object window, or the menu command OBJECTÞ New. The element is created empty. Objects can be added using the CUT and PASTE commands, or when a curve or surface is created with the DESIGN menu.
Most Rapid Tools commands manipulate the target object. This is the object the next command will affect. It can be the root, an element, or some lower-level object. The target object and its contents are darkened in the object window.
For example, if a surface has been chosen to be the target object and the command
OBJECTÞ Delete is executed, the selected surface and its trimming curves will be deleted. The command will not affect any other objects within the system.The target object‘s identifying information is also visible in the message lines. Some attribute information pertaining to the target object, such as the number of control points, will be displayed there, too.
You may select a target object by clicking at any object visible in the object window. To choose "root" for target object, click at the title bar of the elements field.
Instead of operating with the object window, you may also select an object by graphical picking. Use the command
SELECTÞ Pick to select any object you see on the screen.Any command that creates a new object also makes it the target object. E.g., as the command
DESIGNÞ Surface Rotate creates a surface, it becomes the new target object.It is important to choose the correct target object for a command. For example, if a set of facets is the target object–a
Faceted object–, any command will affect all of the facets in that set. If you wish to alter just one facet, make it the target object first.
Active objects
refer to all objects that are of the same dimension as the current target object. Using this concept, you can perform some operations on several objects simultaneously. For instance, all surfaces may be displayed at once by selecting a surface for target object and executing the command VIEWÞ All Draw.You may also make some objects passive. This means that they are not taken into account with the commands for active objects. Passive objects are preceded with a minus (
-) sign in the object window.The target object can be made passive, or active again, with the command
ObjectsÞ ACTIVE/PASSIVE.
Other object window commands, which were not described above are
•
•
DELETE, which deletes the target object from the object hierarchy;•
CUT/PASTE, which are used to move the target object to another place in the object hierarchy;•
MERGE, which joins the target object to the next object in the object hierarchy;•
SPLIT: Splits an element into two.•
RENAME, which is used to rename the target object;•
CHANGE TYPE, which changes the object’s type, from projections to section curves, for instance.
Every time you select an object - not an element - or create a new one, Rapid Tools automatically displays it if
SettingsÞ DRAW: Auto is set.You may use object selection to further effects: by selecting an already selected object again ("double selection"), the object is fitted nicely in the middle of the screen.
As the selected objects are displayed, the system typically erases the previous contents of the screen. Sometimes you may wish to avoid this effect, for instance to view 2D curves simultaneously with 3D surfaces. Button
SettingsÞ DRAW: Menu prevents automatic displaying. How the objects are displayed and erased is then controlled entirely by the user, with the VIEW menu commands.A third alternative is to set displaying entirely off, with
SettingsÞ DRAW: None. This is useful when displaying has no significance and would only slow down the system, e.g., when executing command series.
You cannot judge the accuracy of a surface model by what you see on the screen. Models are rendered up a given level of accuracy which you may adjust using the preferences in the
VIEW menu.One set of preferences controls the the accuracy of wireframes and another set controls the accuracy of the shaded images.
The variables which control the accuracy of wireframes are in the menu
ViewÞ Preferences.The curve accuracy parameter determines how much accuracy (number of points) is used to draw curves. It also affects the display accuracy of wire frame models by their surface curves, i.e., the patch boundaries. Each increase in the parameter's value doubles the number of points used.
The next parameter gives the maximum number of surface curves to be drawn on a surface on both of its (cross- and lengthwise) directions. To draw all the surface's patch boundaries, use a large value. Using a small value makes displaying faster, and saves system memory.
Curves are used in Rapid Tools to represent the following geometries:
• 3D curves loaded from IGES and VDAFS files
• 2D curves designed by the user for constructing surfaces
• 2D trimming curves
• 2D contours in slices load from slice files
• 2D contours designed by the user to repair slices
• Problem areas in the model
• Parting lines
In most cases, the curves are created automatically by the system and they are usually polylines or polygons (closed polylines), i.e. composed of line segments only.
Faceted models
Faceted models
are surfaces made of polygonal facets. They may be created by from primitives, loading an STL file, or triangulating a surface model.
Surfaces
A surface is defined by a control mesh. The surface follows it just like B-spline curves follow the control polygon. The surface has two directions, called the cross-wise and lengthwise directions.
In other words, surfaces are composed of a rectangular array of surface patches. You may think of surfaces as being made by stretching and shrinking an infinitely flexible rectangular rubber sheet—the so-called parameter plane. If there are, say 10
´ 20 patches in the surface, its parameter plane would be 10 ´ 20 units wide.Surfaces can assume a wide variety of shapes which do not necessarily resemble the rectangular patch structure at all, for instance, a doughnut shape (torus). Even more complex surfaces may be defined by trimming, cutting out parts of the surface.
Trim Curves and the Parameter Plane
Surfaces in IGES and VDAFS files may be trimmed. Trim or trimming curves act like a pair of scissors that cut out the portions of the surface that are not needed. They are created in CAD packages as a result of the intersection of two surfaces.
Trim curves are located on a parameter plane. The associated surface, on the other hand, is defined in 3D space. When the trimm curves are mapped to 3D space, they define the boundaries of the surface. Therefore, trim curves have two representations, one in parameter, 2D space, and one in Euclidean, 3D space.
To manipulate the trim curves in detail, you can work directly with the parameter plane trim curves. After selecting the
Trim object, they may be selected by graphical picking just by pointing at the intersection curves in 3D, and if you edit them, all the changes are directly shown in 3D, too.
In its default state, DeskArtes draws all objects in the display area which covers the entire graphics window.
The
SettingsÞ AREA: Four button allows you to display different kinds of objects in four viewports, in the different quarters of the screen. It allows you to display and move (transform) curves and surfaces in all four orthogonal views simultaneously. You may select any of the viewports to move objects, and the changes are seen in all other three views, as well.
For some purposes, for example to create PreView pictures of certain size, you may define a viewport, i.e., select a just smaller part of the display into use. This is done with
SettingsÞ AREA: Part.
The viewing window determines which part of the two– or three-dimensional space is shown on the screen. To control the viewing window, use the commands
VIEWÞ View: Zoom and Pan.You might think of the viewing window as the lens of a camera. It selects the part of the world which is to fit into the picture. By shrinking the window—zooming—the objects are shown larger. By moving the window around—pointing the lens, or panning—you see different parts of the world without changing the scale.
A quick way to automatically define the viewing window so that the target object fits in nicely is to click again at the selected object in the object window. The same could also easily be accomplished with the command
VIEWÞ Object Fit (or even easier, using the shortcut [f]).
To look at 3D objects from different angles, you may change the eye point. This is done with the command
VIEWÞ View:Eye Point. You'll enter into a command state where the viewing direction can be chosen interactively with the mouse.
A quick way to place the eye point directly on one of the axis directions is provided with
SettingsÞ (±)X/Y/Z. To get back to the 3D view, click at SettingsÞ 3D.When you click again on one of these four settings, the opposite view is shown. You should pay attention to the Message Line to know which view is being displayed at a given time.
For efficiency, viewing of wire frame models is done without perspective. Instead, the objects are drawn on the screen using orthogonal projection, which corresponds to an eye point infinitely far from the object. The distance of the eye point has no effect on the view, only the direction from the origin counts.
Note that the eye point or viewing window commands (unlike transformations) have no effect whatsoever on the geometry of the model. The viewing operations merely describe how large a part of the coordinate system is projected on the screen, and the angle from which it is viewed. They do not rotate, scale or move the actual objects, in effect, you move around the object, while the object itself stays in place.
The GL version does all 3D wire frame drawing and shaded images using high-performance graphics hardware which may be available on your computer.
Switching between wire frames and shaded models is done with the
MODE: Wirefr / Shaded buttons in the Settings Window. When using the shaded mode, the object materials take the vector colors which are chosen in the Settings Window.When the object is displayed in shaded mode the first time, it may take some time, but after that the objects are kept in a display lists and will be rendered fast.
When viewing surface models in shaded mode, the accuracy of the images is controlled by the preferences in the
VIEW menu.
The X version's Settings Window has been added a new mode option, namely
MODE: Wirefr / Boxes.By choosing the
Boxes mode, all surface and faceted models will be displayed by showing just their bounding boxes. This can considerably speed up working with large models, if it is not necessary to see all the model detail during the work.
Dimensions and Transformations
Rapid Tools represents all geometry in units. Their interpretation is left to you. When data is loaded into the system, you must remember the units. You can use the scaling functions in the
TRANSF menu to switch from one unit of measurement to another.Measurements are usually displayed to the thousandth of a unit, e.g., 12.340 means 12 whole units and 34 hundredths. Angles for rotations and other such operations are given in degrees (not radians).
Units in IGES files
IGES allows the sender to specify the units used in the file. This information is located in what is called the Global Section of the file and it can be easily found by inspecting the first lines of the file.
As explained in the section titled Loading IGES Files, you can chose to load the data in millimeters, inches, or leave them as they are.
Units in VDAFS files
CAD data in VDAFS files must be expressed in millimeters and, unlike IGES files, there is no way of telling if this rule is followed. In practice, this simple rule seems to be followed.
Units in STL files
CAD data in STL files should be expressed in millimeters and, unlike IGES files, there is no way of telling if this rule is followed. In practice, this rule is widely disregarded and you must use outside, additional information to determine the units used.
Two-dimensional objects are represented in a planar coordinate system, which is defined with a horizontal and a vertical axis. Each point in the plane has a pair of coordinates. The coordinates describe the position of the point relative to the intersection of the axes of the plane, known as the origin.
The coordinates of the origin are thus (0,0). Correspondingly, the point with coordinates (12.3,16.4) is 12.3 units from the origin in the direction of the horizontal axis and 16.4 units from the origin in the direction of the vertical axis.
There's a special way to display the 2D coordinates of any point on the screen. Press the
Control key, and the cursor position will be shown in the message lines. The cursor value changes continuously as you move the cursor.Three-dimensional objects are defined within a system of spatial coordinates. Spatial coordinates have one more axis than planar coordinates. This third axis describes the distance away from the plane that the other two (x and y) axes describe. The third axis is called the "z" axis.
For example, the (x, y, z) coordinates (20.2, 0.0, 10.0) define a point that is situated 20.2 units from the origin in the direction of the x-axis, zero units in the direction of the y-axis, and ten units up in the direction of the z-axis. Incidentally, this point happens to be on the plane defined by the x and z axes, also known as the xz-plane.
The
DIMENS menu contains commands for finding out information about the objects’ size and features. The general dimensioning commands include asking for the center point of an object, its external dimensions, point values on surfaces, as well as their area and volume.The command
DIMENSÞ Slice Dimension leads to an edit mode where you may ask various local dimensions of the curves, such as distances between points on the curves, circle arc radii, angles, etc.
You may change the size, location and shape of objects using different kinds of transformations. The TRANSF menu contains transformation-related commands and it looks as follows:
The available transformation operations are moving, scaling, rotating, and mirroring an object relative to a given point. The point around which the transformations are done is called as fix point, and it can be changed as necessary.
All of the commands in this menu apply to any object in the system, except
Rotate On Facet which can only be used on a faceted (STL) model.Transformations may be executed either with numerical factors, or with graphical interaction to move, scale and rotate the objects with the mouse. Numerical factors can be supplied by hitting a key instead of pressing one of the mouse buttons.
To assist with transformations and with locating coordinate points, a grid is available with the
SettingsÞ Grid buttons. It displays guide lines at chosen densities in the coordinate system, which help to see at which values the cursor is located, and to snap the input points onto the grid. With three-dimensional objects, the grid is shown as a floor in the xy-plane.
When Rapid Tools is launched, the default is to view, or render, surface models as wireframes. In this mode, a set of iso-parametric curves are displayed, in addition to the boundaries defined by trimming curves if they exist.
Other viewing alternatives exist. On GL platforms, you can selected instead shaded mode, and on non-GL platforms you can select box mode.
When shaded mode is used, the default is to view objects with double-sided shading. This is the recommended setting for surface models since it will hide display problems when the surface normals are not oriented consistently and correctly.
If some surfaces fail to get shaded, it is an indication that the trimming curves are incorrect, and you should use the tools in the
FACETOR menu to find the problem. However, the fact that a surface cannot be shaded does not mean that a good STL file cannot be generated. The STL generator is far more robust and reliable.When box mode is used in non-GL platforms, only the bounding box of the objects in the display list is drawn. This can improve performance significantly and you can still carry out tasks such as positioning models.
You cannot judge the accuracy of a surface model by what you see on the screen. Models are rendered up a given level of accuracy which you may adjust using the preferences in the
VIEW menu.Inspecting complex models can be difficult. It may be easier at times to separate smaller portions of the model into another element for visual inspection. You can use the
Collection commands in the SELECT menu for this, and then use CUT, PASTE, and MERGE to put them back together.
All the commands in the TRANSF menu can be used with surface models, except
Rotate on Facet. Since a surface model can be rendered more efficiently than the corresponding STL model, it may be more practical to position the surface model in the workspace of the machine instead of using the STL representation later.
You triangulate a surface model by first selecting the element where it is contained and then invoking the command
Triangulate from the FACETOR menu. The following dialog box is then displayed:A detailed description of each parameter is offered in Part II of this Manual. Here we will mention the most important facts you should remember:
• The tolerances which determine the accuracy of the result are the triangulation accuracy and the trim curve accuracy. The first one specifies the overall accuracy of the result whereas the second one applies only to the surface boundaries.
• The trim curve accuracy should, in most cases, be less of equal to the triangulation accuracy. It is the tolerances that can be applied to small details such as text and threads.
• The maximum triangle edge length should normally be zero except when you plan to offset the result. When zero, this parameter is ignored and relatively long triangles may be created. This parameter is explained in more detail when offsets are presented.
• The size of gaps to fill specifies the maximum distance between adjacent surface boundaries. Boundaries which cannot be stitched together because, say, they are too far apart will be report as problem-areas in the result.
• Usually the normals of the resulting triangulation will be automatically oriented, but you may disable this operation if you wish. Very frequently, commands from
The result of this operation is two elements. The first element will replace the element you chose containing the surfaces with the resulting triangulation. If you want to keep both, you must first make a copy of the surface model.
The second element is a set of curves showing the problem areas. It has the suffix ".
gaps", but the curves are not necessarily caused by missing surfaces or the size of gaps to fill tolerance being too small. For instance, a problem-area may be reported in this element when intersections are missing in the original model.
The first tool for repairing surfaces models was already introduced in the Chapter Files. In that Chapter it was explained how a certain class of problems related to trimming curves can be solved.
Once you have loaded the model, you know it is a valid model if it represents a solid or a closed volume. This can be determined using the tools in the
FACETOR menu:• Use first
• Once you have corrected any problems reported by that command, use the
Verify command to determine if the model is a solid.
Lesson 3: Eliminating duplicate surfaces
This lesson is very simple. A surface model is loaded and, since it contains a duplicate surface, it must be repaired before a triangulation is created.
The example is located in the directory
CXBASE/RT_training in the user account where the system was installed. The CXBASE directory is known by the system, and you can reach it the following way:
A file can only be loaded if it is appears in the File List.
From the File List, find and double-click
luisti.vda. Accept the default parameters and simply click the
OK button. A Note will appear but, at this time, simply ignore it and click the
OK button to make it disappear. Click the
MIDDLE button on the Graphics Window to make the File Window disappear too. Alternatively, you may click the OK button in the lower-left corner of the File Window.
Analyzing the model
From the FACETOR menu, choose Check:Everything
Accept the default tolerance, and simply click the OK button.The boundary of one surface is displayed in
RED, and a new element named DUPLICATE.SURF is created in the Objects Window under root. This element contains a duplicate surface, and the original element, luisti.vdasrf, contains the other copy.The improved model is store in the element
luisti.vdasrf. You could now proceed to triangulate it but that is left as an exercise.
Lesson 4: Repairing trimming curves
Sometimes, you just have to get your "hand dirty" and do some repair work on your own. Here is an example taken from a real model. It is a fairly advanced lesson, and you may prefer to skip it if you are not familiar with surface modeling.
The example is located in the file
tc.vda in the directory CXBASE/RT_training in the user account where the system was installed. You can load the model anyway you please, but we will show a different, more general method below.We will assume the account is named
da but in your computer it may be called something else, like dahome.Recall that a file can only be loaded if it is appears in the middle list of the File Window.
Find and click RT_training from the Directory List. The list of files in that directory should now appear in the File List. From the File List, find and double-click
tc.vda. Accept the default parameters and simply click the
OK button. A Note will appear but, at this time, simply ignore it and click the
OK button to make it go away. Click the
MIDDLE button on the Graphics Window to make the File Window go away too. Alternatively, you may click the OK button in the lower-left corner of the File Window.
Viewing the shaded image
It is worth while having a good look at this model.
If you are using the GL version, simply check it out by selecting the
If you are not using the GL version, from the
PREVIEW menu, choose GL Window:Shaded View. The outline of a window will appear and you must place it somewhere on your screen. Use the RIGHT button on that window to obtain a menu from which you can change the viewing direction.Visual inspection should indicate that there is a problem with this model.
Analyzing the model
Following the guidelines we have stated in the previous example, let us check this surface model:
From the
Accept the default tolerance, and simply click the OK button.The boundaries are now displayed in
BLUE, and a new element named TOUCHING.TRIM is created in the Objects Window in the root list. This element contains the trimmed surfaces with trimming curves that overlap or touch each other. The element tc.vdasrf is now empty. To see the problem, do the following: From the Objects Window, click on
We will correct this the problem in the sequel. Now let us put the surface back into
tc.vdasrf so we can continue using that name: Select
Form the
OBJECT menu, choose Merge.
Correcting the trimming curve
The problem with this model is the parametric representation of the trimming curve. Since triangulations are created in parameter space, a correct triangulation cannot be obtained if the curves in parameter space are wrong.
The constraints on trimming curves in parameter space are exactly the same as for contours in slices that will be used in manufacturing. They must be simple (they cannot be self-intersecting) and they cannot intersect each other, if there is more than one.
From the Objects Window, click on
This model contains one single trimmed surface. There are two trimming curves, and one of them has a point located in the wrong corner.
Double-click on the second polygon, i.e. where it says "
Hit the (lowercase) letter "
o", the shortcut for the entry Curve:Edit in the DESIGN menu.A window containing several icons will appear on the upper-right corner of the display. The mouse buttons now behave differently, and we will use only shortcut commands to modify the trimming curve.
In order to correct the geometry, we must bring the upper-right point to the left, and align it accurately with the neighboring points.
Using the
MIDDLE mouse button, drag the point so that it is located above the letter "v", or it resembles a square. (Note: In parameter space, the coordinate system is two-dimensional.) Hit the (lowercase) letter "
l" and click on the current upper-right point using the LEFT button. Hit the (lowercase) letter "
l" and click on the current lower-left point using the LEFT button. Hit the (lowercase) letter "
w" to exit Curve Edit mode.Check the shaded image again, and it should look like a trimmed cylinder. If you are not sure you corrected the model properly, the correct answer is located in the file
geom_tc.It is not often that trimming curves must be corrected in this way. If such mistakes exist and the model was loaded from an IGES file, follow the guidelines in the Chapter Files. Only when the method described there fails is it necessary to edit the offending trimming curves.
Tips and Guidelines
Dealing with problems as early as possible pays off. For instance, if the duplicate surfaces remain undetected before the triangulation, it is usually much more difficult to repair the STL model.
Duplicates are not always found automatically. Sometimes it is sufficient to increase the tolerance a little. However, if one surface is duplicated by two others, Rapid Tools will only report a problem area.
Rapid Tools contains mechanisms to make visual inspection effective. If you suspect duplicate or overlapping surfaces, you can zoom in the area and use the graphical selection command (shortcut "
g"). Take note that instead of using the mouse, you can hit the keyboard–e.g. the space bar–to select the next closest object. If an object gets drawn twice, it is a duplicate.You can also take a portion of the model and place it in another element. This can make visual inspection much faster and much more effective when models are large and complex.
If the verification or triangulation tools report more than one component or shell and the problem-areas include the boundaries of these shells, then you probably need to combine them in order to obtain the desired model.
One way to combine separate shells is to first separate them in different elements, and then use the Boolean operations to combine them. However, you may not succeed to separate the shells in STL form using the
EDITOR commands. Instead, you can direct the FACETOR to generate different STL models, one for each shell it finds.Shell separation using the
FACETOR is accomplished using the associated function applied to a file. First, write the surface model as a VDAFS file, and then apply the RAPID PROCESS command in the File List pop-up menu from the File Window to that file.
When Rapid Tools is launched, the default is to view objects with double-sided shading on GL platforms. However, this prevents you from seeing gaps clearly, and triangles which have incorrect normals are displayed "correctly". It is recommended that STL models be viewed with single-sided shading.
If the STL model represents support structures, then double-sided shading is the recommended alternative.
When using shaded mode and the triangle normal is perpendicular to the eye (the triangle profile is a line), then you may not see the profile clearly depending on the color you are using.
On non-GL platforms it may be faster to view only the bounding box of the model in some situations for efficiency reasons. You can switch to box mode using the Settings Window.
There is one specialized function for STL models in the
TRANSF menu called Rotate On Facet. Once you select a specific triangle using the Get Triangle command in the EDITOR menu, Rotate On Facet will rotate the model such that the given triangle is located at the origin and is co-planar to the xy-plane.You should not tilt an STL model with respect to the z-coordinate after supports have been generated. If you do, the supports are no longer valid. Any other transformation can be used so long as you apply the same one to both. If you have changed the actual part or the supports and you wish to do exactly the same change to the other element, the same transformation can be invoked again using the
Repeat command in the TRANSF menu.You may find it useful to switch to 4-views from the Settings Window when positioning several models for manufacturing or in preparation for a Boolean operation.
When positioning models with respect to the workspace of a particular machine, it may be useful to view the extents of that workspace.
The directory
RT_training contains a set of files with the prefix cobj_. These files contain the wireframe of the process stated after the prefix. If your favorite process is not available, use cobj_unitbox or cobj_unitcyl, and scale it to the desired dimensions.
In a valid STL model, each triangle must have exactly one neighbor along each edge. Triangles can share vertices and edges but they cannot intersect each other, or overlap. In addition, the triangle normals must be pointing towards the outside of the model.
When a valid STL model is sliced, the resulting contours are simple polygons which do not overlap or intersect. Using well-behaved contours it is much easier to determine which regions of the slice pertain to the part.
If an STL model is not valid, it must be repaired or modified before it is used in a manufacturing process or simulation package.
The expression "corrupt" is used here to refer to an STL model which has been damaged when moved from one physical location to another. For example,
• Files in diskettes may get damaged because the media itself is old or was not handled properly.
• Transmission lines can be "noisy" and the communication protocol is not robust enough to detect changes in the data. For instance,
When this happens, you may not get the entire file loaded into Rapid Tools. In addition, some triangles may have vertices at infinity or very distant from the origin. In these cases, the model cannot be seen clearly but only a couple of lines are visible crossing the screen.
Corrupt files cannot be handled efficiently. In order to eliminate those triangles with illegal vertices, use the command
Object: Cutoff from the EDITOR menu.
A correct, valid STL model must represent a solid or a closed volume. Rapid Tools can easily tell you if an STL model is valid or not. Unfortunately, if it is not valid, you or the designer of the model are the only ones that can determine exactly the nature of the problem and how to fix it.
The amount of repair that is required depends, to some extent, on the manufacturing process or simulation package that will be used. Please read the Guidelines section for more information.
Rapid Tools offers you five methods to repair STL models:
• Using the
• Using the
EDITOR menu you can add triangles using as template a 3D curve. This is much easier than the previous method because the display is not covered by triangles.• You can select a 3D curve and use the
Fill Gap command in the EDITOR menu.• You can select an element containing an STL model and use the
Repair command in the EDITOR menu. This invokes a fully automatic procedure which has two gap elimination methods.In addition, you can combine STL models or separate STL models composed of several shells. These shells can then be re-combined using Boolean operations to obtain the desired model.
Before these features are explained in detail, we must introduce some terminology and concepts.
Gaps and Miscs
Before repairing a model, you must know where the problems are located, the nature of the mistake, and only then choose a suitable tool or method to eliminate the mistakes.
To find the problems areas, if any, you must use the commands
EDITORÞ Faceted:Verify or Repair. These commands assume that the current target object is a triangulated model.If the model has mistakes, one or two error elements containing curves will be created following the target object. They show the remaining problems with the data, if any. These are given suffices ".gaps" and ".misc".
The "gaps" element displays the gaps in the model, whereas the "misc" element includes all other possible problem areas, such as intersecting triangles, triangles with no neighbors, etc. The "gaps" are automatically displayed when each command is ready.
In the optimal case, both "gaps" and "misc" are non-existing, and the user is reported that the command produced a result with no errors remaining.
Lesson 5: Repairing a Gap
The example is located in the directory
CXBASE/RT_training in the user account where the system was installed.
Load geom_luisti
Click on luisti.gaps
Double click the object Curves/3D. Alternatively, you may select Object:Fit from the VIEW menu.The element
luisti.gaps contains only one gap. From the
SELECT menu, choose the Object:Pick option. Alternatively, you may use the shortcut by hitting the letter "g" from the keyboard.Notice that the cursor changed into a cross. You can now point at the gap to selected it.
Move the cursor over the gap and click the
From the
EDITOR menu, select Triangle:Fill GapNotice that no tolerance is required and, consequently, this feature must be used with care. The triangles that fill the gap are placed in an object called
Faceted immediately after the Curves/3D. These triangles must now be combined with the original triangulation and the normals oriented correctly. From the
Click on the element luisti.stl
From the OBJECT menu, select PasteAlternatively, we could have used the option
MERGE from the OBJECT menu because the two elements are consecutive in the list. Click on the element
From the
EDITOR menu, select Faceted:Repair
Accept the default parameters, and simply click the OK button. A Note will appear stating that all problems have been eliminated. Click the
OK button to make it go away.You have now a valid STL model. In this particular example, the fastest alternative to repair the model is to use the
Faceted:Repair command directly with a suitable gap size tolerance. If a sufficiently large tolerance is used, the gap is filled and the normals are oriented at once.
The Automatic Procedures
The automatic procedures can be applied by using the command
Faceted: Repair from the EDITOR menu. Before you use them, you must consider the following issues:• Which gap filling method should be used?
• Which gap tolerance should be used?
When a gap is filled, triangles are added to cover the gap. This is the most common situation. On the other hand, it is sometimes better to merge the gaps, and moving the vertices such that the triangles pair up is a better choice.
There is no single way to measure the size of a gap. Each gap elimination method will measure a gap differently. In Rapid Tools, the gap size is the length of the longest edge that is needed to cover the gap and it depends on the particular method used to repair a particular gap.
As a general rule, if you need to apply both methods to repair an STL model, use the merging method first with a relatively small tolerance, and then use the gap filling method one or more times with larger tolerances.
Guidelines for Repairing Gaps
The amount of repair work that is needed to eliminate gaps depends, to some extent, on the manufacturing process or simulation program that will use the STL model.
The gaps, for instance, may be too small to create manufacturing problems. Or you may prefer to repair some gaps only after the model has been sliced. You can check the dimensions of the gaps using the commands in the
DIMENSIONS menu, or you can already slice the model to see if they can be easily repaired.Depending on the complexity of the problems, it may be better to simply contact the designer. If the model has far too many missing surfaces, it increases the likelihood that the repaired model does not correspond to the intentions of the designer.
A large number of components or shells is an indication that the model is seriously damaged. If you get many gaps and misc, try to separate the model into different components using the
Separate command in the EDITOR menu.If you have the original surface model, you can use the information provided by the
EDITOR to repair the surface model instead, and generate a new triangulation will fewer errors.Sometimes gaps are created because of duplicate surfaces in the input model, incorrectly trimmed surfaces, extra surfaces which simply need to be deleted, and so forth.
The automatic procedures may not always close the gaps properly. In these situations, you must first add a couple of triangles to split gaps in more parts.
It is recommended that you start with a relatively small tolerance, repairing the small gaps first, and then paying more attention to the remaining large gaps.
Guidelines for Repairing Miscs
The triangles included in the "misc" element give a general idea of other remaining problems. The "misc" problems are typically not critical to the manufacturing, for instance, if the erroneous triangles are very small or degenerated. You may determine the seriousness of the problems by viewing the element on the screen, using zooming and other tools.
On the other hand, if they do constitute large portions of the model, repairing them can be difficult.
The individual curve sets in the "misc" element have names assigned to them, describing the nature of the corresponding problems. You'll see the names by selecting a curve set, and looking at the system message lines. The significance of the different "misc" error curve sets are:
EDUPL: Duplicate triangles.
EETRS: More than two neighboring triangles sharing the same edge.
EFLOAT: Floating, isolated triangles, not attached to the rest of the model.
EEDGE: Edges with more than two triangles attached.
EINCONS: Edges along which triangles couldn't be oriented consistently.
EINTERS: Intersecting triangles with no common vertex.
EVINTERS : Intersecting triangles which share a common vertex.
EEOLAPS: Overlapping triangles which share a common edge.
EVOLAPPS : Overlapping triangles which share a common vertex.
EOLAPS: Overlapping triangles which don't share a common vertex.
The following alternatives exist to repair "misc" problems:
• If you have the original surface model, you may try repairing it and generating a new triangulation with less or no "misc" problems.
• If the problems are created by missing intersections, you can use the Booleans to compute them. You must first get the different components or shells in different elements. This is relatively easy if you have the original surface model, and usually difficult if you only have the STL model.
• You can delete the offending triangles. This creates a gap which can then be filled using the various tools available.
Deleting the offending triangles can be done in several ways. You can use the EDITOR
Þ Faceted: Repair command and set separate offending triangles to YES. If that fails, you can get them using one of the three Triangle: Get flavours in the EDITOR menu. It is very easy, for instance, to delete or separate in a different element all the triangles that share a common vertex.If the
EDITOR separates portions that are too large resulting in a gap that cannot be filled reasonable well by the automatic procedures, you can first refine the model and only then separate the offending triangles. The Refine tool can be found in the TOOLS menu.
DeskArtes Rapid Tools STL reduce and refinement functions are meant for manipulation of large or otherwise bad triangulation for simulation purposes. The specific systems under consideration at the time of writing are MAGMASoft and MOLDFLOW simulation packages.
For MAGMA users, gaps and too large a number of triangles is the major problem with STL-files. The number of triangles can be reduced according to user given tolerances.
For MOLDFLOW users, the shape of the triangles is also a major problem with STL files. With combination of triangle refinement and reduce operations the user can generate a triangle mesh with triangles having a better aspect ratio.
MAGMASoft usage
For such users, it is usually enough to reduce the number of triangle in the original model with two parameters on, Tolerance and Maximum angle. These parameters how much the result differs from the original shape.
The number of triangles is reduced by deleting vertices and generating a new triangulation for the gap that results from this operation. Each time a vertex is deleted, the number of triangles is reduced by 1. If the resulting triangulation is too far from the original model, the vertex is not removed. The distance criteria is controlled by the tolerance parameter.
The minimum angle prevents changes in regions like sharp corners. In other words, vertices defining sharp corners are not candidates for removal.
Thin triangles should not be a problem with MAGMA software.
The operation is started with
TOOLSÞ Faceted: Reduce.
MOLDFLOW usage
For MOLDFLOW users, a set of operations including both refinement and reduce is required. The operation is started through
TOOLSÞ Faceted: Refine menu.Refinemet alone can already improve the aspect ratio of the triangles while at the time it will add triangles to the mesh which can be used later by the reduction tool. Improving the aspect ratio by refinement is not practical due to large number of triangles that would result. Therefore, a combination of refinement and controlled reduction is more effective.
The following guidelines are provided to obtain a better triangulation:
1. Reduce the model with
2. Refine the model using as grid value the average edge length.
3. Reduce the model using
Use Tolerance, Use Angle, Use Edge, Use Grid and Multiple pass.4. Repeat the previous step with same parameter values as long as you are not satisfied or no more changes can be seen.
5. Reduce the model with
Use Only Short.6. Improve the aspect ratios with
Use Height.Step 1 above removes very thin triangles from the original model, reducing the number of generated triangles later. This step can be omitted.
Step 2 creates the refined model. The refinement value depends on the model size, detail size in the model and available main memory. If the suggested value does not generate a sufficient amount of triangles, then the model can be refined again using the average.
Steps 3 and 4 reduce the number of triangles while preserving the shape of the model. The triangle vertices at the grid points are utilized to generate the new triangulation.
Step 5 finally reduces some thin triangles which still might exist in the model. This step can be omitted.
Step 6 produce some improvements in the triangle shapes. This step can be omitted.
Representation of Sliced Models
When a sliced model is loaded into Rapid Tools, or generated by Rapid Tools, then entire collection of slices is stored in one element. Each slice will be stored in one 3D curve object, and each slice may contain one or more polygons representing the contours of the slice.
By default, slices are assigned colours depending on their type and properties:
• Closed outter contours are
• Closed inner contours are
BLUE.• Open contours are
RED.• Support structure contours are
YELLOW.Since contours representing part geometry must be closed,
RED contours indicate errors in the model.
Rapid Tools has several ways to display a large amount of slices effectively.
When the element containing the sliced model is displayed using the Viewing commands, only a pre-defined number of slices is displayed. This number is specified using the command SLICES
Þ Preferences.The command SLICES
Þ Scan Slices allows you to browse thru the slices quickly, whereas the LEFT and RIGHT arrow keys allow you to browse each slice at a time once you have picked the first one.To browse only the ones which have gaps, use the command SLICES
Þ Find Gap.
Sliced models can be repaired immediately when they are loaded from the File Window, or you may use the command SLICES
Þ Close Gaps.If the automatic procedures do not produce acceptable results, you can use the curve editting tools. These are explained in detail in Part II Design. At this time, you must remember that the curves you design must be polygons or polylines (open polygons).
Another usefull set of tools for repairing problems other than gaps can be found in the
TOOLS menu. When curves overlap, they can be split and recombined to form the desired shape very easily.The purpose of this Chapter is to show you features that allow you to:
• Give a thickness to an STL model
• Split an STL model in any way you wish
• Add pins and holes to STL models so they can be combine properly after being built.
Offsetting: Giving A Thickness To An STL Model
Giving a thickness to an STL model can serve the following purposes:
• If the STL model is not a closed volume, giving it a thickness will result in a solid which can then be used for manufacturing.
• If the STL model is already a solid, giving it a thickness creates a solid with a thin shell and, consequently, less volume. Depending on the process you are using, the end result is less costs because less material is used, or the part is built faster or even more accurately.
This operation is refered to in Rapid Tools as offsetting. Before you can offset an STL model you must make sure that either it is a valid solid, or it does not have any unintentional gaps. Once you have selected the STL model as your target object, the command
TOOLS: Offset will pop-up a dialog box in which you supply the parameters.The resulting offset will be placed in an element following the target object. The offset is not guaranteed to be smooth and the result is strongly affected by the offset distance in relation to the size of details present in the original model. I.e., if the offset distance is large compared to the size of the features in the original model, the offset not may appear smooth.
Lesson 6: Creating a Solid from an Open Model
We will use the corrected model of
tc.vda which is stored in geom_tc as our first example of offsetting. The corrected surface model will be triangulated, and the resulting STL model will be offsetted, and a solid created.The example is located in the directory
CXBASE/RT_training in the user account where the system was installed.
Load geom_tc
Select the element corrected
From the FACETOR menu, use the command Surface: Triangulate
Use a triangulation tolerance equal to 0.1 instead of 0.05
Click on the OK buttonOnce the triangulation completes, the
corrected element will be replaced by the triangulation and called corrected.stl. A new element called corrected.gaps will be created.Since the model is not a solid but a single sheet, the gap element contains one single curve that follows the boundaries. Before this model can be manufactured, a solid must be created.
From the
Accept the default parameters, and simply click the
OK button.Once the tasks completes, the offset will be placed in a new element called
corrected.off. At this point, you many choose to keep it or, if it is not acceptable, it can be deleted and a new offset with different values can be generated.If you decide to keep it, it must be merged or combined with the original STL model in order to obtain a valid solid. Let us do that now.
Select the element
From the OBJECT menu, select the command MERGE. Alternatively, you can use the pop-up menu from the Object Window by pressing the MIDDLE mouse button which is easier because you do not need to move the mouse after selecting the element. Now we must orient the normals. From the
EDITOR menu, select the command Faceted: Repair. Before you click the
OK button, you may wish to set the gap tolerance to zero since there are no gaps and only the normals need to be oriented.
Exercises
Use a triangulation tolerance equal to 0.01. Use a triangulation tolerance equal to
0.01 again, but set the maximum triangle edge length to 3.0.
Lesson 7: Creating a Solid with a Thin Shell
We will use the STL model of
cubic.stl. The model must be loaded, the shape of the triangles modified, an offset created and finaly combined with the original to form a closed volume representing now a hollow object.The example is located in the directory
CXBASE/RT_training in the user account where the system was installed.
Load cubic.stl; simply double-click on the name.The objective of this lesson will be give it a wall thickness of
0.2mm (about 0.01in). If you take the dimensions of some of the features of this model, you will notice that some walls are as thin as about 2.54mm, or 0.1in.Before the offset can be created, we must change the shape of the triangles so that relatively long ones are not close to small ones.
Select the element
From the TOOLS menu, select the command Faceted: Refine. A dialog box will now appear. The grid size parameter is already highlighted and it is the one you should change to
5. Click on the
OK button.Once it completes, a new element called
cubic.ref will be created. This is the one which will now be offsetted. Unlike the previous lesson, you will change one more parameter in addition to the offset value. In this lesson, you will set the round corners option to YES. Select the element
From the TOOLS menu, select the command Faceted: Offset. A dialog box will now appear. The offset distance parameter to
0.2, and the round corners to YES. Click on the
OK button.Once it completes, a new element caleld
cubic.off will be created. You must now combine it with the original model in cubic.stl. There are different ways to accomplish this. Select the offset graphically using the command
Use the command
CUT from either the OBJECT menu or from the pop-up menu in the Object List. Select the original triangulation either graphicaly if it is displayed on your screen, or by clicking on its name,
cubic.stl, in the Object List. Use the command
PASTE from either the OBJECT menu or from the pop-up menu in the Object List.The element cubic.stl has now two
Faceted objects. You should now use the Faceted: Repair command from the EDITOR menu to ensure the normals are correctly oriented. Select the element
From the
EDITOR menu, choose the command Faceted: Repair. Before you click the
OK button, you may wish to set the gap tolerance to zero since there are no gaps and only the normals need to be oriented.
Tips and Guidelines
The offset is sensitive to the shape of the triangulation. Very long triangles near small ones can create havoc with the offset. There are ways in Rapid Tools, though, to overcome such problems.
If you have the surface model, then it is usually best to limit the size of triangles already when the triangulation is created. This is done by setting a positive value for the parameter maximum triangle edge length.
If you do not have the original surface model, then you can use the Refine module to split the triangles into smaller sizes.
The best way to check the quality of the result is to slice it.
Generating offsets is often time consuming. You may prefer to use a background process instead of blocking the user interface. To use a background process, simply write the STL model you wish to offset onto an STL file, and then use the appropriate option from the
RAPID PROCESS command in the File List pop-up menu in the File Window.
You may wish to split a model in two or more pieces when:
• The part cannot be built in one piece in your machine.
• A mold is needed instead of the part, and the geometry of the mold can be derived from a user-defined parting surface.
The easiest and quickest way to split a model is to chop it. Chopping in Rapid Tools consists of cutting the model with an infinite plane. Whenever possible, use it instead of the alternatives described in this Section. Chooping is invoked using the command
Faceted: Chop from the TOOLS menu.This section of the Manual explains how to create elaborate parting surfaces which you can then use to split your models. It is structured as follows.
Except when creating simple primitive surfaces, you must first design a curve before you can construct a surface. Therefore, this section first describes the different curves you can create in Rapid Tools. Next, the methods used to create surfaces are described. Finaly, a lesson on how to split a model is given.
Curve Modeling
You need to create one or more curves before you can create certain surface types in Rapid Tools. Besides, you may need to repair trimming curves and contours on slices and the information here is useful for those purposes too.
When you are creating a curve, however, you must choose a suitable representation. The representation is chosen by choosing the appropriate input mode with the
SettingsÞ REPS buttons. The possible input types are B-spline, BŽzier, and Linear.Whether to use B-spline or BŽzier curves is largely a matter of application and taste. B-splines have less points and allow for easier and faster sketching, while BŽzier curves give more freedom and control for detailed work.
However, when building a surface, the projection curves must be B-splines. Thus, it is possible to do all your designs with B-splines, while BŽzier modeling is not as generally applicable. When starting to learn DeskArtes, it may be best not to change the input type at all, and work just with B-splines. BŽzier curves may be added to the repertoire later on.
Curves are entered interactively with the commands
DESIGNÞ Curve: Input and edited with DESIGNÞ Curve: Edit.Other commands that create standard curves are
DESIGNÞ Curve: Polygon, Circle, Arc, and Offset. These commands do not need user interaction other than parameters, such as the desired number of points, circle radius, offset distance, etc.
Surface Modeling
The result of a surface modeling operation in Rapid Tools always results in a faceted model. Internally, a true surface model is created and then triangulated using a user-defined tolerance.
The tolerance can be changed using the
DESIGNÞ Tolerance command. Beware that this is the same tolerance used for triangulating surfaces. Changing this tolerance will modify the corresponding parameter in the FACETORÞ Triangulate dialog box.
Primitive Surfaces
The simplest means of creating a surface is calling for a primitive surface. The different surface primitive types available are plane, box, sphere, cylinder, cone and torus. They are all obtained with the command
DESIGNÞ Surface Primitive, which asks for the primitive type, size, etc., as parameters.
Extruded and Rotational Surfaces
The commands
DESIGNÞ Surface: Extrude and Rotate produce different kinds of sweep surfaces. The Extrude command sweeps a projection curve a given distance in one of the coordinate directions.Command
Surface Rotate revolves the projection curve around an axis.Both commands require at least one projection curve defined in the target element. Command
Surface Extrude may also be given several curves in the same projection element, in which case several surfaces will be created at the same time.
Building a Surface
The command
DESIGNÞ Surface Build is the most flexible way to create surfaces. You may use it in several different ways, to obtain different results. Therefore, it deserves a more thorough explanation than the other surface creation commands.Building a surface requires that you first design a section curve and one or two projection curves. These curves must be all under the same object, and the last curve is always assumed to be the section curve.
As the surface is built, the section curve is transformed into three-dimensional space to meet the path of the projection curve(s). The section curve is rotated so that it is perpendicular to the projection plane. The resulting surface will exactly pass through the section curve in 3D, while obeying the given side views, as well.
How the section curves are transformed is shown below. The section curve center point is matched at the projection curve knot points.
Rules about Building
There are certain rules which must be obeyed when building surfaces:
• For certain mathematical reasons, the projection curves must always be B-splines. (Section curves may be either B-splines or BŽziers.)
• When two projection curves are used, both projection curves must have an equal number of control points. Adding a control point to one projection curve means that a similar point must be added to the other projection curves.
Lesson 8: Splitting with a parting surface
In this lesson, we have selected a model which you should be familiar with if you have executed the automatic demo to completion. It is the dinossaur.
Load geom_dino; simply double-click on the name. Select the x-direction for the eye point by pressing the
X button in the Settings Window. Enter Curve Edit mode by either selecting the command
Curve: Input from the DESIGNER menu, or using the shortcut [i].A new element is automatically created, and you are given the chance to assign a name if the default does not suit you. Since the name is no so important here, we will use the default, i.e.
part2. Click on the
In Curve Input mode, you use the
LEFT mouse button to show the location of the control points. With the default settings, a B-Spline curve will be created. Now you can create any curve you wish as follows: Always with the
To show the location of the subsequent points, click once to get a rubber band line, and then a second time to show its final location.
If you move the mouse before you release the button, you already get a rubber band line which follows the mouse. In this case, when you release the button, the position of the point is already assigned.
When you do not want to add any more points, click on the "Smile" icon, or hit the
w-key.Once you complete the curve, the final shape is displayed. If you are not satisfied, you can edit the curve. Control points can be moved around, new ones added, and old ones deleted.
To edit the curve, simply choose the command
Curve: Edit from the DESIGNER menu, or use the shortcut [o]. Alternatively, you can just delete the curve, and try designing a new one.Assuming you are happy with the curve you designed, we will now build a surface and use it to split the dinossaur. You cannot continue this lesson if the curve does not cut the model.
Select the command
Accept the default parameters and press the
OK button.By default, Rapid Tools choses parameters for the extruded surface such that it cuts through all the objects displayed. If you with to see the surface, you must change the eye point to, say,
3D. Next, you can split the dinossaur. Select the 3D eye point from the Settings Window, and use the shortcut
From the
TOOLS menu, select the command Faceted: Boolean. The first dialog box will ask for the name of the second element. Since the dinossaur is the only other element displayed, it is the default value, and you can press the
OK button. The second dialog box is used to tell the system what to do with these two elements. Choose split into four parts.
Press the
OK button.If the two elements intersect properly, there is one or more intersection curve which splits them in two or more pieces. The result of this command will be four new elements. Two of these elements are the pieces resulting from the first element, and the other two new elements are the pieces from the second element.
In order to obtain two solid parts, the element
part2.inner must be copied and merged with dino.outer and dino.inner. The element part2.outer is of no use to us in this example, and can be deleted. Make a copy of the element
Use the
CUT and PASTE commands to merge one with dino.outer and the other one with dino.inner. Use the command
Faceted: Repair from the EDITOR menu to orient the normals of dino.outer and dino.inner.
Tips and Guidelines
Boolean operations will only work properly if the models intersect. If they do not intersect, the correct procedure is to simply merge or combine them, and then use the
EDITOR to orient the normals.If you wish to make a mold and the geometry is such that you can design the parting surface, then you can first surround the part with, say, a box. After you have combined the box with the part, you can use the parting surface to split the result and obtain the two halves of the mold.
Splitting can also be useful for core extraction. For example, suppose you have a tube. You can design two surfaces that cut through the ends, and both can be used at the same time to obtain the core.
DeskArtes Rapid Tools support generation is meant for generating supports for fluid-based Layer Manufacturing Technologies (LMT). These processes cannot handle overhangs without supports. Supports fix the details of the models to the vat bottom or to the surroundings so that they do not float away until they connected properly to the other parts of the model. Additionally, the model must be attached to the vat bottom so it can be removed without breaking.
DeskArtes Rapid Tools support generation creates supports for STL-models. The models should be solids or closed volumes, otherwise the result may not be correct. To verify if the model is a solid, use the
Verify or Repair functions in the EDITOR menu.Once you have positioned the part in its location in the workspace of the machine, the supports can be generated. A sufficient space must be left for the supports between the part bottom and the vat bottom.
The support generation is launched using the
SUPPORTSÞ Supports: Generate menu bringing up a File Selection window for selecting the parameter file. Canceling is possible with CANCEL button. Pressing OK brings up a Edit support parameters -dialoque box for support parameter editing. Pressing OK starts the support generation if the Edit support parameters is set to NO.If you want to check and edit the paramters before starting the support generation, push YES and OK buttons. This brings up the Support parameter dialog box for easy editing of support parameters. See also the Chapter Editing support parameters for further information.
Pressing
GENERATE button in Support parameter dialog box activates the support generator. A percentage box appears in the middle of the screen and it is updated until the support generation is ready. When ready, the supports are read into the workspace and displayed in yellow color.After the support generation is finished, the supports can be viewed and edited with the
EDITOR menu commands . When the supports are acceptable they can be written on a disk file. Further, the supports and the model can be sliced and written in a suitable format, like CLI or SLC for manufacturing.
If the model is a solid, the normals of each triangle is directed towards the outside. The normal can be used to classify the triangles in three groups:
Down-facing |
The normal vector is pointing downwards, and has a negative z-component. |
|
Up-facing |
The normal vector is pointing upwards, and has a positive z-component. |
|
Vertical walls |
The normal vector is parallel to the xy-plane. |
The areas that need supports are formed by down-facing triangles. Not all down-facing areas need to be supported, but only those in which the angle between the normal and the unit negative z-vector is small. This angle is a user-supplied parameter to the support generator, and it depends mainly on the process and resin used to construct the part.
Areas that need supports are called support or overhang areas. Once the areas that need supports have been identified, the borders or edges of these areas are classified as self-supported or non-supported.
A self-supported edge is adjacent to a portion of the part which is extending downwards, such as a vertical wall. In other words, it is attached to a portion of the part which has already been built. On the other hand, a non-supported edge is adjacent to a portion of the part which is extending upwards.
A steep surface area is a surface area where the angle between the surface normal and z-axis is large.
Good support generation requires different types of supports with different features in the model. There should not be too many supports nor too few. Too many are tedious and difficult to remove, and too few may not properly support the part, causing incorrect manufacturing of the part.
Currently, the support generator can create five different support types:
Web support |
This is the most typical type of support, and it is used in all large down-facing areas. |
|
Profile support |
Profile support is used to envelope Web supports. |
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Chain support |
This support is used in sharp or thin down-facing areas in the model. If a Chain support cannot be created, a Web support is used. |
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Point support |
This support is used with down-facing, pointed vertices. |
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Gusset support |
Gusset support is used to support a overhang area from the nearby vertical walls. |
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Web and Chain supports can have teeth, structures that minimize the contact area between the supports and the part. They allow the supports to be removed more easily and with less damage to the surface of the part. The geometry of the teeth is controlled by the following parameters:
The tip of the teeth is the contact area with the part. Because supports may touch both down and up-facing areas, the user may wish to create teeth on both ends of the supports whenever this happens. For consistency, the teeth are classified in up-teeth and down-teeth.
Normally the teeth are projected directly upwards or downwards from the support triangles. This may cause very dense or even overlapping teeth near very steep surface areas. In these areas the teeth can be created parallel to the part surface normal direction.
By means of the General Parameters, the user has rough control over the type of support that is chosen for a given area. The General Parameters are explained in detail in the next Section.
For a simple down-facing point, a Point support is always chosen.
For an area of size greater than the Minimum area, the support generator considers first Gussets, then Chains, and finally Web supports, in that order. Under special circumstances, no supports are generated. The decision tree is illustrated below.
The user can disable the generation of some support types. Those supports are replaced with the support types below the disabled type in the decision tree. If the user sets the Selected supports only selection on, no replacement is done and the areas are left without supports.
Used... |
When... |
No supports |
The area can be supported with Gussets but it is a "portal". All the points in the area are close enough to a supported edge, including the perimeter of the non-supported edges. The largest distances are specified by self-supported and overhang support distances. |
Gussets |
The distance between non-supported edges and supported edges is larger than the overhang support distance. In other words, non-supported edges are too far from the part that has already been built in previous layers. In addition, it must be possible to create Gussets that satisfy the constraints on their Gusset geometry. These constraints are given in the portion of the dialog box reserved for the Gussets. |
Chain |
If all facing non-supported edges around the overhang area are closer to each other than given Max area width value for Chain supports. Also, if a Gusset generation has failed, supported edges are also used for distance evaluation. If the constraints are kept, an Chain support is generated. Sharp, down facing edges are only supported with Chains. |
Web |
If none of the alternatives above has been chosen, on succeeded, then a Web support is created. |
The user has access to all the parameters controlling the support generation. This enables the user to use his/hers knowledge and optimally choose the best support geometry for his application.
The support parameters can be divided into two classes. The first class of parameters are general, affecting all different support types. The other set of parameters only affect a specific support type.
The general parameters are found in the first three lines of the Support parameters dialog box. The support type specific parameters are divided into separate fields: Web, Chain, Point and Gusset in the middle of the dialog box.
Angle |
Angle parameter specifies the maximum angle to be supported. The angle is evaluated between the triangle normal and negative z-co-ordinate axis. The angle A must satisfy 0² A < 90. |
Min area |
Minimum area specifies the minimum size of the area to be supported. If the area is smaller and there is enough support from the surrounding area, no supports are generated for the area. Currently, "enough surrounding support" means that 2/3 of the perimeter is composed of self-support edges. |
Steep surface angle |
Use modified teeth if the angle between the surface normal and z-axis is larger than given Steep surface angle value. |
Edge offset |
Edge offset specifies a distance between the supports and supported area edges. This prevents the supports from colliding with the part. This is usually larger than the Overhang edge offset-value. The value given should be a value suitable both for supported edges and non-supported edges. |
Non-supp. edge offset |
Non-supported edge offset specifies the distance between the supports and the non-supported edges of the support area. The value given should be the smallest acceptable value. This value is used only if the normal offsetting of overhang areas with edge offset -value fails. |
Vertical offset |
Vertical offset value gives the amount of offset from vertical walls in the model. This prevents the supports from colliding with the original model. The value given should be the smallest acceptable value. |
Tooth overlap |
Tooth overlap gives the value of tooth and support triangles overlap, when using tooth shaped triangles between the real support and the part. This affects the removal of the supports after manufacturing. |
Portal distance |
Portal distance gives the maximum overhang distance without supports for H-like structures, where the overhang area is supported from more than one side. These geometries are called portals. |
Cliff distance |
Cliff distance gives the maximum overhang distance without supports for turned L-like structures, where the overhang area is supported only from one side. These geometries are called cliffs. |
Generate-selection : |
Generate selection allows the user to prevent the building of selected support types. |
Selected supports only |
Selected supports only selection allows the user to disable the replacement of those support types which are not generated. |
Area output-selection : |
When area output selection allows the user to direct the supports from each different overhang area into separate Facet-object in the result element. |
Note: Currently Self support distance and Overhang support distance are not handled separately. Instead, the smaller of values is used.
Web support parameters control the web support generation.
X spacing: X spacing parameter gives the distance between adjacent web hatches parallel to x-axis.
Y spacing: Y spacing parameter gives the distance between adjacent web hatches parallel to y-axis.
Rotate: Rotate parameter gives the amount of rotation around the z-axis applied to the web hatches. This value should be from 0-45 degrees.
Up overlap: Up overlap gives the amount of overlap between the part above the supports and the supports.
Down overlap: Down overlap gives the amount of overlap between the part below the supports and the support.
Create profile: Web profile selection sets on and off the profile support triangle generation for a web support. Profile support follows the overhang area edge, in the distance given with parameters Supported edge offset and Overhang edge offset.
Tooth parameters define the shape and distance of teeth between the model and the real support triangles. Teeth can be used to make the connection between the part and supports weaker, allowing easier breakaway of supports. Also, holes in the support structure allow the trapped liquid to drain from the part. Note, that the model has to be positioned high enough from the vat bottom when using the teeth. The limit is two times the maximum height of the teeth.
Up tooth: Up tooth selection allows the user to set support up edge tooth generation on/off.
Down tooth: Down tooth selection allows the user to set support down edge tooth generation on/off.
The meaning of distance:, base length , tip length and height parameters for both Up tooth and Down tooth selection are explained in the Section Support types.
Chain support parameters control the edge support generation.
Spacing: Chain spacing-parameter gives the distance between adjacent hatches along the Chain support middle line
Cross length: Chain cross length parameter gives the length of the perpendicular hatches with the support.
Root length: Root length parameter gives the length of the triangles of the pedestal build between the chain supports and the building platform.
Root height: Root height parameter gives the height of the triangles of the pedestal between the chain supports and the building platform.
Max area width: Max area width parameter gives the maximum width of Chain support area. Chain supports are trimmed against the overhang area edge.
Up overlap: Up overlap gives the amount of overlap between the part above the supports and the supports.
Down overlap: Down overlap gives the amount of overlap between the part below the supports and the support.
Tooth parameters define the shape and distance of teeth between the model and the real support triangles. Teeth can be used to make the connection between the part and supports weaker, allowing easier breakaway of supports. Also, holes in the support structure allow the trapped liquid to drain from the part. Note, that the model has to be positioned high enough from the vat bottom when using the teeth. The limit is two times the maximum height of the teeth.
Up tooth: Up tooth selection allows the user to set support up edge tooth generation on/off.
Down tooth: Down tooth selection allows the user to set support down edge tooth generation on/off.
The meaning of distance:, base length , tip length and height parameters for both Up tooth and Down tooth selection are explained in the Section Support types.
Point support parameters control the point support generation.
Point supports are generated when a downward pointing vertex is not supported by any other support type.
Plates: Point plates gives the number of plates in the point support.
Max area : Max area gives the maximum area to be considered as a point area. This parameter is no yet implemented.
Plate length: Plate length gives the length of individual plates with a point support.
Root length: Root length parameter gives the length of the triangles of the pedestal build between the point supports and the building platform.
Root height: Root height parameter gives the height of the triangles of the pedestal build between the point supports and the building platform.
Up overlap: Up overlap gives the amount of overlap between the part above the supports and the supports.
Down overlap: Down overlap gives the amount of overlap between the part below the supports and the support.
Gusset support parameters control the generation of gusset supports. Gusset supports are used, when a thin stripe of overhang triangles are attached to supporting wall.
Max length.: Maximum length gives the maximum width of a gusset support area.
Max angle.: Maximum angle gives the maximum angle between the gusset triangle outer edge and the negative z-axis. Outer edge is the edge which is not attached to the supported part.
Min angle.: Minimum angle gives the minimum angle between the gusset triangle outer edge and the negative z-axis. This value is used if gusset generation with Maximum angle fails.
Spacing: Spacing gives the spacing between consecutive gusset triangles.
Up overlap: Up overlap gives the amount of overlap between the part above the gusset support and the gusset.
Side overlap: Side overlap gives the amount of overlap between the part besides the gusset support and the gusset.
Border offset: Border offset gives the distance of a gusset triangle upper edge end point from the overhang area edge.
Wall offset: Wall offset gives the distance of a gusset tooth from the supporting wall.
Top offset: Top offset gives the distance of a gusset triangle up edge from the supported area, i.e. the gusset tooth height.
Following figure explains the affect of the last four parameters above:
Up angle : |
Up angle gives the maximum angle between the overhang triangle surface and xy-plane still allowed to be supported by gussets. |
Down angle :![]() |
Down angle gives the minimum angle between the supporting wall triangle surfaces and xy-plane still capable to hold gusset supports.
|
By default the support parameter files are stored in
System directory under the home directory of DeskArtes Rapid Tools. You can use the support parameter File selection window to locate and store support parameter files into suitable directories.When you start the support parameter editing with
SUPPORTSÞ Supports:Parameters command, the support parameter File Selection window is displayed. This window enables you to browse through the directory tree either by typing the directory path in the up most Filter area or simply by double clicking on directory names in the left hand side Directories area.The default post fix for DeskArtes support parameter files is '
*.par'. This is also the default filter used with the Filter area. Only the file names with matching the given filter are displayed in the Files area. Allowed wild cards are '?' and '*' for one character and any number of characters, respectively.After you have located the wanted parameter file, you can select it by double clicking on the name or writing the name in the lowermost Selection area. Also pressing OK instead of double clicking can be used. The editing operation can be canceled with
CANCEL button.APPLY
button applies the modified Filter to the Files area and displays the files according to the Filter.INFO
button gives the user some information on the selected parameter file.If you press
OK the Support parameter dialog box appears for easy editing and storing of support parameter values. After all parameters are properly set they can be save into a file by pressing SAVE TO FILE button. This brings up a File Selection window for the parameter file name.You can quit the editing operation with
CANCEL button in the lower right corner of the Support parameter dialog box.Pressing
GENERATE button launces the generation of supports with given parameter values. The parameter values are not stored into a file. If you want to store them into a file, plase push SAVE TO FILE button first.
The DeskArtes Rapid Slice can be used to slice both the part and supports. From the part a set of contours is outputted in various formats, like SLC or CLI. The generation of hatches inside the part contours is left to RP-machine control software.
The slices generated from the supports can be used to control the machine directly if a suitable conversion software is available.
Note: With the GL version of DeskArtes Rapid Tools the REFRESH-mode should be set to NO when viewing slices.
Through the File Window, you may read and write information into DeskArtes, display pictures on the screen, and perform various tasks related to file maintenance.
The File Window appears with the command
SYSTEMÞ Show Files or by clicking the middle mouse button within the graphics window. Hide it the same way, or click the OK-button in the lower left hand corner of the File Window.The File Window commands are in three pop-up menus. By pressing and holding the middle mouse button in the leftmost window (directory field) you'll get the directory pop-up menu, Pressing the middle mouse button in the middle window (file field) shows the file pop-up menu. Pressing the same button in the rightmost field pops up the help directory pop-up menu.
All of the File Window commands apply to the selected files or directories (displayed in black). You may select a file or a directory by clicking at its name with the left mouse button.
All file names have an identifier, either a prefix in the beginning of the file name, and/or a suffix at the end. The identifier determines the contents of the file. Every time a file is written from DeskArtes, the system automatically adds an identifier.
Typically, prefixes are used for files which are internal to DeskArtes, and not recognized by other systems. Suffices are used with general file formats, which are used as standards for communicating between different systems.
The following identifiers are in use:
geom
model file (the whole model from root down)safe
backup copy (the latest modeling situation)cobj
object file (target object only)log
command series filepic
any picture filepvpic
PreView picture file
igs
IGES data transfer filevda
VDA-FS data transfer filedxf
DXF data transfer filestl
Stereolithography data transfer filehpg
HPGL plotter filecli
CLI format slice filesli
SLI format slice fileslc
SLC format slice fileeps
Encapsulated PostScript fileaps
Adobe Illustrator PostScript filetif
TIFF format fileA capital letter Z after the file name means that the file is compressed. Compressed files take much less disk space than uncompressed ones. Most DeskArtes commands are able to treat compressed files just as uncompressed ones.
Note: The identifiers of file names are typically not be typed in when the system asks for file names as parameters. For example, if you wish to store an STL file called "part.stl" you should only answer "part" when asked for the output file name. DeskArtes adds the rest automatically.
SHOW TYPES/ACCESSES
This command displays the read/write authorizations of all the directories and files in the File Window. If given again, the files are displayed plain again.
The authorizations are displayed as a three-letter combination for "everyone-group-me", where "-" means no authorizations, "r" means read authorization, and "w" allows both writing and reading. For example, "rww" would mean that both you and your group may read and write to the directory, but others may only read it's contents.
See command
DIRECTORY: PROTECT for further explanations.
CHANGE DIR commands
These commands allow for selecting the model directory anywhere in the UNIX file hierarchy. The available commands are:
UP
Moves one level up in the directory tree. You may also perform the equal operation if you select the ".." item in the directory field.DOWN
Moves down to the currently selected directory. You may also perform the equal operation if you double-click at any directory name.PATH
Asks for the UNIX path of the desired directory.CXBASE
Moves to the DeskArtes primitives/demo database.HOME
Moves to the user's home directory.
DIRECTORY: INFO
This command displays the directory information, i.e., size, read and write authorizations, owners, and the last modification and access dates. The information in a shown in a separate file info window.
DIRECTORY: CREATE NEW
Asks for the name of the new directory, then creates it. By default, directory names have two parts, typically the user name attached to the model name as
username_modelname. You may also leave either part empty if you wish.
DIRECTORY: REMOVE
Deletes a directory and all the files within it. This cannot be undone. DeskArtes asks for confirmation before deleting.
DIRECTORY: RENAME
Gives a new name to an existing directory.
DIRECTORY: CLEAN
Deletes the "unnecessary" files within a directory. These are the object (
cobj), teach (log) and size (.sz) files. This cannot be undone. DeskArtes asks for confirmation before deleting.
DIRECTORY: COMPRESS
This command compresses all of the files within the selected directory. This saves disk space. To decompress the files, use the command
FILE: (UN)COMPRESS.
DIRECTORY: PROTECT
This command sets the read and write authorizations of a directory.
The command asks, who are to be given the read and write authorization. Possibilities are
all, group, and me. The authorizations of a directory may only be changed by the user who created the directory in question.The
all option gives everybody the right to use the directory. Group typically means all of the people working on a project. The group may be given rights to examine your model directories (read authorization) while keeping the right to change them to yourself (me).
DIRECTORY: TO TAPE
Writes the contents of the selected directory on magnetic tape, diskette, or some other data storage device.
DIRECTORY: ALL TO TAPE
Makes a tape backup of the DeskArtes database.
FILE: INFO
Displays the file information, such as name, type, read and write authorizations, owner, size and time last changed in the file info window.
FILE: READ
Reads a file into DeskArtes or displays the selected file on the screen. Alternatively to selecting this command from the menu, you may double click at the file name to read a file.
Note: If you try reading a file that has been created by another UNIX user, the read might fail due to a protection violation. See the
INFO and PROTECT commands.
Model file (identifier
geom)Reads a DeskArtes model for further work within DeskArtes. If needed, the system asks if the current model should be replaced, or if the file model will be appended to the current one.
Object file (identifier
cobj)Reads a DeskArtes object after the current target object, or as its sub-object.
DXF file (identifier
dxf)The command reads a DXF file created with some other modeling system for use within DeskArtes. Version 11.0 of the DXF standard is supported.
IGES file (identifier
igs)Reads an IGES file (created with some other modeling system) for handling with DeskArtes. Version 5.3 of the IGES standard is supported.
Reading IGES files is fairly well discussed in Part I , Loading Surface Models in Chapter Files. You should read that Section first before you continue.
Only geometrical elements or entities are taken from IGES files. Non-geometrical entities like annotations and views are totally ignored.
Practically all geometrical entities can be read, including NURBS or spline curves and surfaces, rotational and ruled surfaces, and so on. A list of entities found and processed in the IGES file is printed to the command window where DeskArtes was launched.
The command asks for an approximation tolerance as a parameter. It is used for all data conversions, including degree reduction, conversion of Offset entities, re-computing trimming curves, etc.
As another parameter, the tolerance for optimizing trim curves is asked for. If set to a positive value, it automatically performs the command
FACETOR Þ Surface: Reduce Trims to the model. This is useful to prevent having "too" accurate trim curves.The third option, recompute all trim curves, makes the program to trim all surfaces with the 3D trim curves in the IGES file, instead of the 2D parameter space trim curves. The 2D trim curves are generally preferred by DeskArtes, and they are faster to read, too. However, if there are any problems with reading the file then you may try to improve the situation by re-computing the trim curves from 3D.
If there are no 2D trim curves defined in the IGES file, then the re-computation is done automatically. It might take a long time to read complex models from IGES files, especially if the 2D trim curves are not defined. In such a case, just leave the computer to compute in peace.
Since IGES files are first converted to VDAFS before they are read, you may prefer to perform this step in the background using the
CONVERT command from the File pop-up menu.
VDAFS file (identifier
vda)Reads a VDAFS file (created with some other modeling system) for handling with DeskArtes. Version 2.0 of the VDAFS standard is supported.
Reading VDAFS files is fairly well discussed in Part I , Loading Surface Models in Chapter Files. You should read that Section first before you continue.
The two first parameters are the same as when reading IGES files. As a third parameter DeskArtes asks, whether the surfaces should be stored in just one element, or separate elements for each surface.
It might take quite a long time to read complex models from VDA files. In such a case, just leave the computer to compute in peace.
Stereolithography file (identifier
stl)Reads the contents of an STL file (Stereolithography standard) as a faceted model. Both the binary and ASCII formats are supported.
Slice file (suffix
cli, sli or slc)Reads the contents of a slice format file. As parameters, it asks if possible errors in the file should be automatically corrected.
If the file contains slices of both the actual model, as well as its support structures, they will automatically be separated in two different elements in DeskArtes.
Sun Raster file (suffix
pic or rgb)Displays a Sun Raster file format picture on the screen. The picture may have been created with DeskArtes, or any other CAD system.
The picture may be erased from the screen by pointing at it with the mouse and hitting
q on the keyboard.
TIFF file (suffix
tif)Shows a TIFF picture file on the screen. The picture may be removed from screen with the
q key.
Text file
If the file to be read is not any of the formats mentioned above, it is assumed to be an (ASCII) text file, and it is loaded for text editing in a separate window.
You may choose one of the UNIX text editors "more", "vi" or "emacs" for viewing the file. The "more" editor is easiest for users who don’t know UNIX, while the two latter also allow for text editing, i.e., changing the contents of the file.
FILE: WRITE
This command writes geometry, pictures, or other data into a file, from which it may later be read.
Note: writing a file may fail if you don't have the authorizations to write in the chosen model directory. Another possible reason can be that the file system is full. The authorizations may be checked with command DIRECTORY: INFO. The available disk space is seen with the UNIX command "
df", issued in a command window.As a parameter, the command asks for the type of file to be written. The possibilities are explained in the following.
Model (identifier
geom)Writes all of the model geometry (under
root) into a model file. This is the best way to save your models permanently.
Object (identifier
cobj)Writes only the target object, e.g., an element of surfaces, into an object file.
Picture (identifier
xwpic)Stores the contents of any window on the screen or a selected part of the graphics window into an image file. Which window or window part to store is selected as parameter, and/or shown with the mouse.
Data transfer
Various data transfer formats are available to move geometry to other CAD/CAM and Desktop Publishing systems. The available data transfer formats are:
·
IGES (identifier igs)Writes the contents of the target object (curve, curve set, surface, element, or root) into an IGES file. This is used to transfer data into other modeling systems, e.g. for CNC machining. Version 5.0 of the IGES standard is supported.
The command writes everything under the target object to the file. To write only surfaces, for instance, you may first gather them into one element with command
SELECTÞ Collect Actives.As parameters, the command asks for the file name, output format separately for the surfaces and trim curves, and a choice of optional flags.
NURBS is more widely recognized than Splines. If the receiving system is a solid modelling system, it is better to send Spline trimming curves instead of polylines.
Which selection of parameter to choose depends on the flavors of the receiving system, and if not from the handbooks they may best be found by experimenting.
You can also read about
vda2igs in the Batch Tools User Manuals. If the requirements of the receiving CAD system are listed there, then you can first output a VDAFS file, and then use that program stand-alone to obtain the IGES files.·
VDA-FS (identifier vda)Writes the contents of the target object (curve, curve set, surface, element, or root) into a VDAFS file. Version 2.0 of the VDAFS standard is supported.
Other details with using the command are similar to IGES output.
·
DXF (identifier dxf)Writes the contents of the target object into a DXF file, with several flavors for the output format. Version 11.0 of the standard is supported.
The DXF standard is mainly used to transfer data into 2D drafting systems. The standard holds also the faceted surfaces and even parameteric surface descriptions, but not surface intersections.
The command asks for the following parameters:
• Include DXF header or not? Some systems, like AutoCAD, prefer the header to be included, other do no not require it.
• Separate arcs/lines? This helps the receiving system interpret geometric features in the curves.
• How to store the faceted model? The alternatives are 3D faces, and polyface mesh. The latter takes less space to store, but the 3D faces seem to be more generally recognized by the receiving systems.
• How to separate the DXF layers? This determines what the receiving system stores in its different layers, to make the manipulation of the objects easier. The alternatives are to separate the objects (faceted models) as they are stored in DeskArtes inside different elements, or according to their material definitions.
• Store all to ENTITIES section? YES or NO, depending on what the receiving system likes better.
·
SGI Inventor (identifier iv)This outputs the selected faceted model in the SGI Inventor format. The shading colors assigned to the models will be transported, too. The option is available only with Silicon Graphics operating systems IRIX 5.x (or higher).
·
PostScript (identifier eps or aps)Writes a 2D object (curve, polyline, set of curves, text etc.) into a Postscript file.
Two slightly different PostScript flavors are available, and can be chosen as a parameter: Encapsulated PostScript (
eps) and Adobe Illustrator PostScript (aps)
Rapid Prototyping
·
STL (identifier stl)Writes a faceted model or an element of those into the
.stl file format. DeskArtes asks, whether the data should be stored in ASCII or binary format.The actual model should always be written into a separate file from its supports/hatches, or otherwise the receiving RP system may get confused with their meanings.
The actual model should form a solid, and have its normals oriented correctly to be manufactured. It is always recommendable to check these things with the command
EDITORÞ Faceted Repair prior to writing the final STL file.·
Slice (identifier cli, sli or slc)Writes a set (element) of planar 3D polylines into a
.cli, .sli or .slc file format, specific to different rapid prototyping systems.The target element should contain either slices of the actual model, or supports/hatches only, but not both at the same time. Supports and hatches must be written into a separate file from the actual model, or otherwise the receiving RP system may get confused.
FILE: DELETE
Deletes
the selected file.Note: The file is deleted permanently, the command cannot be undone.
FILE: RENAME
Changes the name of the file. The new name is asked as a parameter.
Note: This command requires you type in the file identifiers (prefix or suffix), too. It is good to keep the identifier of the file—if there is no special reason for not doing so—DeskArtes needs them for recognizing the file types.
FILE: CONVERT
This command has two different uses:
1. It converts an image file into the desired file format. The user is asked, into which format he wishes to convert.
For the time being, standard Sun Raster files, Rgb files, TIFF files and XWD files may be converted into the Sun raster, Rgb or TIFF formats. Other conversion options may be requested from your DeskArtes dealer.
2. The command also works as the interface for some of the DeskArtes Rapid Tools batch tools which perform file conversions.
The file conversions that can be made are STL to IGES, IGES to VDAFS, VDAFS to IGES, binary STL to ASCII STL, and vice-versa. Sliced models can be converted to and from CLI, SLI, SSL, and SLC.
The files will be converted in the background and usually a note will be displayed when the process completes. Output file names are assigned automatically by the system, and a log file associated to the name of the input file is usually created.
FILE: RAPID PROCESS
This command gives you the possibility to use many of the menu commands in the background. In this way, tasks like triangulating a surface model or offsetting an STL model are done by separate processes and you can continue using the user interface. When the process completes, a note is displayed on your screen, and you must press the
OK button before using the result.The result of using this command will be one or more files, including one log file. The names of these files are created automatically and they will replace any file with the same name, if there happens to be one.
You are free to continue using the user interface while the process executes the command you chose, including changing directories, or even starting another background process.
The file you have selected must be either an STL or a VDAFS file. If you select an STL file, you can apply to it functions found in the
EDITOR, TOOLS, or SLICES menus. If you select a VDAFS file, you can use the Verify or Triangulate functions found in the FACETOR menu.There are differences between the corresponding functions. The major differences are explained below.
Triangulating Surface Models in the Background
The dialog box looks the same as the
FACETORÞ Surface: Triangulate, but it includes an additional parameter, separate components. When set to YES, it will automatically separate in different STL files the various components or shells it finds.If the selected file is named, say,
file.vda, and it contains two shells, then the result of the triangulation will then be two STL files named file1.stl and file2.stl.You must be carefull when using this feature on the same file with different parameters. Increasing the gap tolerance can reduce the number of shells, and you must then read the log file to know how many files to collect. Files generated by previous uses of this feature remain if you did not delete them.
If you chose component separation, you cannot orient the normals of the various STL files automatically. You will have to apply the corresponding
EDITOR function on each file separately.
Slicing STL Models in the Background
The corresponding MENU function,
SLICESÞ Slices: Generate, is more flexible. It allows you to repair gaps and it distinguishes between part and support geometries, features which are absent when using this function from the File Window.The background processes can generate IGES and HPGL files directly, but it cannot generate SLC nor SLI files; you would need to load the resulting slices in the user interface and re-write the slices in order to obtain those file formats.
FILE: (UN)COMPRESS
Compresses
or decompresses a file. Compressing makes the file much smaller, saving a lot of disk space.
FILE: TO TAPE
Writes the selected file on magnetic tape, or some other data storage device.
PRINT PIC
This command prints the selected image file onto the default (color or gray scale) printer. The printer is defined with the environment variable $DA_PRINTER.
The Help Directory Pop-Up Menu
HELP DIR: SELECT
Selects a help directory to be shown in the rightmost column of the file manager. Help directories are required when you wish to move, copy or link files from one directory to another.
Unlike the other File Window commands, you first click the command button, and then the directory to be chosen.
HELP DIR: PATH
This command allows you to select the help directory anywhere in the UNIX directories.
You select the directory by typing in its complete UNIX path name in a special help path window. The previously used help directories are listed there, too, and you may select them by pointing.
HELP DIR: CLOSE
This command does nothing else than just empties the help directory field, if you don't want to have it shown.
HELP FILE: INFO
Shows the information on the help directory, similar to command
DIRECTORY INFO.
HELP FILE: READ
Reads a file from the help directory, just as command
FILE READ for ordinary directories.
LINK FILE: FROM HELP DIR
Creates a so-called symbolic link. This makes a file chosen from a help directory seen from your model directory, as well.
Linking files is usually better than copying files, as linked files only take up disk space for the original file. Note, however, that if you change the linked file, you will in fact affect the original one.
LINK FILE: TO HELP DIR
Works as the previous command, but the other way around.
COPY FILE: FROM HELP DIR
Makes a copy of a file from the help directory into the model directory. The resulting copy has the same name as the original. If a file with this name exists, the user will be asked to confirm that the old file can be replaced.
COPY FILE: TO HELP DIR
Works as the previous command, but the other way around.
MOVE FILE: FROM HELP DIR
Moves the selected file from the help directory into the model directory.
MOVE FILE: TO HELP DIR
Works as the previous command, but the other way around.
The Object Window, which is situated at the left side of the DeskArtes user interface, contains a pop-up menu with general commands that deal with objects.
The target object is chosen by pointing the cursor at the desired object name and clicking the left mouse button.
The possible contents of the target object are visible in the lower window fields. For example, if an element has been chosen for target object, the lower fields display the objects that make up the element.
If the element or object contains more than a hundred (100) sub-objects, they will not be automatically displayed. To show them, click at the title bar of the window field in question.
If there are more objects than fit in the window field, you may scan the list of objects with the mouse. Slide the right hand scroll bar of the window field with the middle mouse button.
If the display mode is set to
DRAW: Auto (see Settings Window), DeskArtes automatically displays the target object when you select it. If the new target object is of different type than the previous one, e.g., surface vs. projection curve, the old screen contents are erased.Selecting the target object again ("double selection") will fit it in nicely the middle of the screen.
As an exception (to avoid undesired erasing), nothing changes on the screen if an element is selected. However, selecting the target element again will draw all the surfaces under it. Selecting the same element a third time will fit its surfaces in the middle of the screen.
Sometimes you may wish to avoid automatic displaying, for instance to view 2D curves simultaneously with 3D surfaces. The display mode
SettingsÞ DRAW: Menu disables automatic displaying. How the objects are displayed and erased is then controlled entirely with the VIEW menu commands.A third alternative is to set displaying entirely off, with
SettingsÞ DRAW: None. This is useful when displaying has no significance and would only slow down the system.
The Object Window pop-up menu commands are equal to those in the
OBJECT menu. They are included in the Object Window for the greatest ease of use, to be found near the object lists.The Settings Window contains commands which are related to the way objects are input and displayed, and whose current state is useful to have visible on the screen while working. The Settings Window is a pop-up window, that can be displayed and hidden by clicking the right mouse button within the graphics window.
Note that some Settings Window changes, such as changing the grid step, turning trim curve display off, etc., affect only when the next display command is executed.
After each command that affects the geometry of the model (not, for example, display or file commands), DeskArtes makes a so-called backup file (called
safe_system) which contains the modeling situation preceding the command. This is used for undoing commands with the UNDO command.By clicking at
BACKUP, you may prevent DeskArtes from making backups. You might want to do this with very large models, as it might take too long to write the backup file after each command. To allow making backups, click at BACKUP again.However, there's an alternative to make the backups faster. Normally the backup files are stored in the current model directory. If the model directory is located somewhere else in the network than the workstation from which DeskArtes is used, it will be much faster to store the files on the mahine's local disk. This behavior can be controlled with command
SYSTEMÞ Backup Control.
This command cancels the last commands which has changed the geometry of the model.
If
BACKUP has been disabled, UNDO reverts to the last backup file available.If the command is executed immediately after launching DeskArtes and selecting the directory,
UNDO reads in the latest modeling situation (backup file) within the directory. This means that model geometry will not be lost in case of a program crash or electric failure.See command
SYSTEMÞ Backup Control on how to optimize the speed of UNDOing.Note: File Window or visualization commands may not be canceled with
UNDO.
If the same modeling commands need to be performed several times over, it is useful to make a command series of the commands, i.e., teach a lesson to the system.
The command
TEACH writes all the following commands and editing functions into the specified command file, until the TEACH button is clicked again. The lesson may then be automatically repeated with the EXEC button (see below).Note: During the time the command series is being recorded, you may not use the Object Window or the File Window commands. Target object selection must therefore be performed with the
SELECT menu commands.
This command executes a command series, created with
TEACH, a given number of times.Before execution starts, you are asked whether new command parameters will be asked for at every step of the execution, or whether the already given ones will be used.
You can also tell whether the commands should be executed automatically, or if you want to confirm each step before executing.
Finally, there’s an option to have a brief delay between the commands, to make the execution look nicer. If you want to run the command series as fast as possible, just use zero delay.
Note: As you give
EXEC, the commands are executed just as they were taught, with no intelligence added. In particular, be sure you have the right target object selected before you start, the program won't be able to decide it for you. Note also that graphic picking may be dangerous under TEACH: it could pick wrong objects if the viewing window or the objects change with EXEC.
The buttons
B-spline, BŽzier and Linear next to the text REPS determine the input representation of curves produced with the DESIGNÞ CURVE menu commands.For example, if the type is set to
B-spline, the command DESIGNÞ Curve: Input assumes that the points entered are control points for a B-spline curve.The default value for the input type is
B-spline, which generally applies well to any kind of modeling work.Only one of the
REPS buttons may be selected at a time—hence, they are called radio buttons.
Polygons
Polygons
are closed linear curves consisting of straight line segments. Polygons may be used, among other things, to create extruded faceted models, and to represent the trim curves of surfaces.Polygons are created with the CURVE menu commands when the input type has been set to Linear.
.
B-Spline Curves
B-spline curves
follow the form of a control polygon, the vertices of which are known as control points.To interactively create a B-spline curve, set the input mode to B-spline, and use the command DESIGNÞ Curve Input to enter the control polygon.
To move, add, or delete control points, enter the command DESIGNÞ Curve Edit. You could also produce sharp angles, straight line segments, circular arcs and fillets, etc. In other words, practically any curve shape may be defined using the available curve editing functions.
It is good to know the following facts about the B-spline curve properties:
• The curve follows the form of the control polygon smoothly, but it does not usually pass through the control points, i.e., it approximates them.
• Each control point has a corresponding knot point which does lie on the curve. Knot points are important especially in building surfaces.
• Moving a single control point only affects locally the part of the curve that is close to the point. The rest of the curve remains unchanged.
• A double control point (two control points at the same location) produce a smooth corner. A triple point produces a sharp corner at the tripled control point.
• The end points of an open curve are triple. The last three control points of a closed curve are the same as the first three. These facts are usually hidden from the user, but good to know.
• The tangent direction from a triple point of the curve (such as an end point) is towards the next control point.
• Generally, a curve looks smooth if it does not have too many control points, and if the points are distributed in an even manner relative to each other. If two or more control points are on the same side of a curve, there will be no undesired fluctuations in their part of the curve.
BŽzier Curves
The BŽzier curve is another way of representing smooth curves. As with B-splines, BŽzier curves are input with the command
DESIGNÞ Curve Input, but first the INPUT type has to be set to BŽzier.When inputting a BŽzier curve, you will place its knot points directly. The curve will pass through (i.e., interpolate) them.
Each knot point has two handle points. It is possible to use them to manipulate tangent vectors while preserving the knot point locations.
With the command
DESIGNÞ Curve Edit you may locally move the BŽzier knot points and handles, add new knots without changing the shape of the curve, define arcs and fillets, and further manipulate the curve shape.
The
SHARP and SMOOTH buttons control the input curve shape. Depending on which button is pressed down, a curve adopts a sharp or a smooth shape with command DESIGNÞ Curve: Input.If
Linear has been chosen for representation (c.f., REPS), the SHARP/SMOOTH buttons have no significance—polygons are always "sharp".
The buttons next to the
AREA text allow you to change the display area which DeskArtes uses to view the objects.
Whole
Selecting AREA: Whole makes the entire graphics window the display area.
Part
Clicking at the AREA: Part button allows you to select a smaller viewport of the graphics window for use. The desired part of the display area is shown by drawing a rectangle with the mouse. Point first at the lower left corner, then at the upper right.
Four
The AREA: Four button divides the graphics window into four quarters. All 3D objects are then displayed simultaneously in the x, y, z and 3D view quarters of the display,.
Each quarter can be separately zoomed and panned with the corresponding VIEW menu commands, or used for graphical picking of objects.
Change the display mode with the three buttons. The possible settings are:
Auto, Menu, and None. The default setting is Auto.The meanings of the display modes are:
Auto
Objects are displayed automatically as they are selected, or created.
Menu
Objects are not drawn when selected, but only when new objects are created, or when a display command is issued from the VIEW menu.
None
Objects are not drawn only when a display command is issued from the VIEW menu. Use this option when displaying takes too long and is not needed, e.g. when deleting several objects in a row, or when executing long command series.
The buttons in the Settings Window,
REFR: Single / Double / None control how things are refreshed with the GL version when the menus/windows change within the Graphics Window.Generally all objects on the screen are redrawn when a menu or some other window disappears from the screen. With large models this feature may be too time consuming and it may be disabled by setting the refresh mode to
None.Double
buffering refreshes the models more nicely than single buffering, and its use always is recommended on 24-bit machines. Single buffering gives better color resolution with shaded models on 8-bit.
Double
Double
buffering refreshes the models more nicely than single buffering, and its use always is recommended on 24-bit machines.
Single
Single
buffering gives better color resolution with shaded models on 8-bit.
None
Generally all objects on the screen are redrawn when a menu or some other window disappears from the screen. With large models this feature may be too time consuming and it may be disabled by setting the refresh mode to
None.
With the GL version, you may switch between 3D wire frame drawing to shaded images any time. The mode is chosen with the
Wirefr / Shaded buttons. Note: When the object is displayed / shaded the first time it will take some time, but after that the objects are kept in the GL display lists and will be rendered fast.The X version, on the other hand, provides a switch to display the objects accurately as wire frame models, or faster just by their bounding boxes. This may beee useful if accurate model detail is required for the application at hand.
Wirefr
Switches to wire frame mode.
Shaded
Switches to shaded mode.
Boxes
Switches to the bounding box display mode.
Wire frame models are drawn adaptively, so that smaller objects have less accuracy than large ones. With the drawing parameters you may further control the display accuracy so that large objects, too, will be drawn faster.
Trim
This button determines whether trim curves are displayed on the surfaces or not. It often takes longer to draw the trim curves in 3D than the actual surfaces. In such a case it is better not to draw the trim curves at all.
Txtr
This button determines whether texture areas are displayed on the surfaces or not.
This
ON/OFF toggle button may be used to temporarily disable clipping of objects.The clipping planes are actually defined with command
VIEWÞ Define Clips. Their positions are not affected by this CLIP command - it just tells whether to apply them or not.
The grid makes it possible to snap points to exact coordinate values, and helps visualize the dimensions of an object.
The grid affects the points automatically only with the
DESIGNÞ Curve Input command. In curve editing, the grid is used only when requested with the editing function g.The command
TRANSFÞ Object Move applies the grid, if the right mouse button is pressed during the command. All other commands use the grid purely as a visual aid.
Grid
The
Grid button switches the grid on and off, when clicked.For three-dimensional objects, the grid is shown as a "floor" on the xy plane.
Show
The density of the grid shown is displayed next to the
Show text. Change the density by clicking at it and typing in the density.
Snap
The "magnet effect" of the grid is controlled with the
Snap value. Points will be snapped at the integer multiple values of the Snap value, when the grid is applied.
The eye direction buttons allow you to quickly set the eye point to one of the coordinate axes, and back to three-dimensional space. The buttons are labeled
(±) X, Y, Z, and 3D. Each button sets the eye point to the corresponding view direction.Whether the view direction is set to one of the axis, or to 3D, has a big impact on how 3D transformations work. See the
TRANSF commands for further details.
The eight vector color buttons in the bottom of the Settings Window change the display and shading color of the target object.
What the colors actually are may be chosen interactively with the command
SYSTEMÞ Set Colors.The
SYSTEM menu contains commands that deal with the workings of the DeskArtes system itself.
This command shows the File Window, and hides it again. If the File Window is visible, a black square appears next to the menu item.
Another way to show the File Window is by clicking the middle mouse button in the graphics window.
This button hides and shows the Object Window. The alternative is to click the right button in the graphics window.
This button shows and hides the Settings Window. Another way to show and hide it is by clicking the right mouse button in the graphics window.
You may customize the layout of DeskArtes by moving and re-sizing any of the DeskArtes windows. The command
Save Layout saves the current sizes and positions of the windows for later use. The saved layout will be used when you launch DeskArtes the next time.To move a window, point at the title bar of the window, press and hold the left mouse button, and drag the window to its new location. To re-size of a window, point at the lower right corner of the window, and drag with the mouse as with moving windows. Edit mode icons may be moved similarly; however, they may not be re-sized.
When the command is executed, the user interface color window pops up. You may change all the user interface colors used by DeskArtes with it.
In the user interface color window, the colors are divided into three groups:
• vector colors, defining the colors in which the objects are displayed;
• user interface, defining the colors of buttons, windows and their background;
• grid colors, defining the three colors used for drawing the grid.
All the colors are changed in the same way. Select the color you want to change by clicking at the small button to its left. Slide the red, green and blue rulers to change the color. When happy with the color, click at the small button again.
You may thus change each color one at a time. It is also possible to change several colors at the same time by having several small buttons down.
Once ready with the color changes, you may take the colors into temporary use, for the current modeling session, by clicking the
APPLY button, or cancel all the changes by clicking at CANCEL. To store the selected colors permanently, to be used when you next time launch DeskArtes, click at SAVE.You may cancel all changes without exiting from the color selection window by pressing the button
DEFAULT (for the currently selected colors) or ALL DEFAULT (for all colors).When changing the colors, it is useful to have some objects shown in the graphics area in different colors. Thus you are able to see how the colors look, and whether they can be easily distinguished from each other and the background color. It’s a good idea to set the grid on while editing vector colors, too.
This command allows you to assign different meanings to the mouse buttons. Thus you may change the way the windows pop up and disappear with the mouse buttons.
Normally the left mouse button pops up the object window. With the
Preferences dialogue box, it can alternatively be made to pick objects, like command SELECTÞ Object Pick.The middle and right mouse buttons can be assigned to pop up the file and settings windows one at a time, or make the right button pop up both the object and settings windows. (The latter is useful especially if you have assigned picking to the left button.)
This command allows you to decide if the backup files (
safe_system) are stored in the current model directory, , or into the machine's local /tmp directory.This selection has a significant impact on the file storage speed, if the model directory resides somewhere else in the local area network than the workstation own disk. Storing the backup files on the machine's local disk is much faster than writing files over the network.
The choice of the backup directory will be memorized between sessions, if you store the choice with the
SAVE button in the command's dialogue box.Note: If the local /tmp directory is used for backup, it is on the user's or system administrator's responsibility to clean up the /tmp directory once in a while. Otherwise the directory may run out of disk space.
This command resets the viewport, display window, eye point and grid size to their respective default values. In addition, the PreView picture memory will be emptied (as with the command
RENDERÞ Done).
This command exits DeskArtes. The system asks if you really want to quit. Choose
No to change your mind.The
OBJECT menu contains commands that generally affect objects, independent of their type.
The
New command creates an empty element.. The name of the element is asked as a parameter.
The command
Copy creates a duplicate of the target object.
The command
Delete deletes the target object from the object hierarchy.
The commands
Cut and Paste can be used to change the order of objects within the object hierarchy.Command
Cut deletes the target object and places it into an internal object buffer.Next you must choose a new target object. Then execute
Paste, and the buffered object is inserted ("pasted") after the new target object.It is also possible to apply several
Paste commands in succession, so as to create several instances of the model in the object buffer.
This command splits an element into two. All objects before the selected object go (remain) in one element, while the target object and those after it go into the second. The name of the second element is asked as parameter.
The command
Merge joins the target object to the next object, e.g. adding the contents of the next element to the selected element.The objects to be joined must be of the same type: for example, you may not join a surface to a faceted model.
The command
Rename gives a new name to an element.
The command
Change Type changes the object type of a set of curves, for example from x-projections into z-projections.
The command
Active/Passive makes the target object passive (if it is active) and back.Objects that are not of immediate interest should be made passive. For example, the commands
VIEWÞ All and the command SELECTÞ Collect Actives only apply to active objects. Passive objects would not be dealt with.For example, you might like to make two elements active and all the rest passive. You could do this by making
root the target object, selecting Active/Passive to make all elements passive, and then making the two elements active the same way.The
SELECT menu contains alternative ways of executing object selections. It also gives easy access to a writing of files.The menus are useful especially in that they provide quick shortcuts for commands, which would otherwise have to be found with the mouse.
In particular, you must use menu commands when creating command series with the command
SettingsÞ TEACH, as it does not allow you to choose objects from the Object Window.
This command allows you to choose the target object just by pointing at an object in the graphics window and clicking the left mouse button. You may pick anything which is shown on the screen. This is a handy way of moving among different elements, instead of selecting from the object window.
As an exception, if the target object is a section curve, trim curve or a texture area, picking is allowed from the same curve set only (which is what the user would expect).
It is possible to pick trim curves directly from the 3D view. If your target object is a trim curve or a set of them and you point outside the trim curve viewport, the program picks the trim curve which is closest in 3D.
Sometimes it may be difficult to point exactly on the desired object, and a wrong object gets picked. To reselect, click at any key on the keyboard (not a mouse button ) at the next pick attempt. The previous, unintentionally selected target object is erased, and the next nearest object is chosen as target.
These commands select the next or the previous object among objects at the same level of the object hierarchy. This is a very handy way of moving between several curves in the same curve set, for instance.
Makes the (next) surface the target object.
Finds a surface by its name. This may be used, in particular, with surfaces which have been read in from IGES and VDA files. The names are then the same as they were in the corresponding data transfer files.
Show
Next and Show Prev erases the current target object and displays the next and previous one, respectively. The associated shortcuts are the right and left arrow keys, respectively.These commands are handy when scanning slices.
This command copies all active objects into one element.
The name of the new element will be
ALL. Any existing element named ALL will be deleted. If you wish to avoid this, rename the old element before executing the Collect command.The
ALL element will automatically be made passive. This is to avoid drawing the same surfaces twice with commands DISPLAYÞ All: ...
This command copies all the objects currently shown on the display, and places them into their own element. It works like
SELECTÞ Collect Actives, but it is based on what is shown on display, not on the object's type.You are asked the name for the new element. If you accept the default name "ALL", the previous "ALL" element is replaced by the new one.
You may use the command, for instance, to copy a set of curves and a drawing of it into their own element, for plotting or data transfer.
This command either copies or separates chosen objects into their own element.
You are first asked the name for the new element.
Another paremeter specifies if you wish to select object which are totally inside the rectangle you will draw, or all objects that are close to it. The first choice is usually more convenient for accurate selection.
A third parameter specifies whether the chosen objects should also be kept in their original elements, or deleted.
After giving the above parameters, draw a rectangle at the objects you wish to select, and they are stored in the new element.
Works the same way as the File Window command of the same name.
This menu contains commands to display objects, and adjust the viewing window and direction. The display commands are very frequently used, so their keyboard shortcuts should be learned as early as possible when starting using DeskArtes.
Any of the display commands may be interrupted by pressing
ESC or Ctrl-C in the graphics window.
With
Pan [x] and Zoom [z], if you press the MIDDLE mouse button, the view will change continuously. With left mouse button, and always in four views, these commands work as before.View
[v] with the GL version rotates the object directly, not the bounding box. The rotation center point depends on which mouse button you press:• left button selects the closest point on the model as the rotation center
• middle button places the rotation center to the middle of the object
• right button continues the rotation around the last defined center point.
The same mouse button functionality has also been implemented for the X version, but there the bounding box is displayed during the rotation.
Draws the target object in the currently chosen viewing window.
Fits the target object in the middle of the display area. Other objects which were shown before giving the command are erased.
Blinks the target object, i.e., erases and redraws it. This is a handy way of checking which is the target object.
Displays all active objects which are of the target object type.
For example, if the target object is a surface, all the other surfaces in active elements are displayed. This way you don’t have to go to the other elements to display the surfaces individually.
Fits all active objects nicely in the middle of the display area.
Erases the whole display area.
Moves the viewing window
. Press a mouse button down at any point on the screen, move the cursor to where you wish to have its new location, and release the button. The size of the object on the screen will not be changed, but only moved to a new location.With the GL version, if you press the MIDDLE mouse button , the view will change continuously. However, in four views and edit modes, panning works always with the rubber-band as above.
Sets a new viewing window
. The size of the window can be set either graphically, or by stepwise scaling.• To zoom in freely, press the left mouse button down, with the cursor at the center of where you want to zoom.
Move the mouse: a rectangle showing the new window is displayed. The window is fixed by releasing the mouse button.
• By clicking the middle mouse button, the size of the window becomes narrowed by half, in other words, the objects show bigger.
With the GL version, if you press the MIDDLE mouse button, the view will change continuously. However, in four views and edit modes, zooming works always with the rubber-band as above.
• By clicking the right button, the window becomes twice as big—the objects are shown smaller.
• If you click at any key other key than a mouse button, you will be able to pan instead of zooming.
The last mentioned feature is useful especially in the various edit modes, where only the zoom function is available—you may use it to pan, as well.
This command defines the direction of the eye point for the different viewing commands.
When the command
View Eye Point is executed, horizontal and vertical movements of the mouse rotate the view sideways and up, accordingly. The object rotates continusly as you move the mouse, and you may change the direction any time while rotating. Click again at the mouse button when ready.With the GL version, you may view the object in close-op zooms. The rotation center point depends on which mouse button you click to start with:
• left button selects the closest point on the model as the rotation center
• middle button places the rotation center to the middle of the object
• right button continues the rotation around the last defined center point.
As a fourth alternative, you ay click on any key on the keyboard. This will pop up a parameter box where you can set the viewing direction as numeric values.
The command
VIEWÞ View: Move Light allows you to continuously move the light point around the object.The light point moves with similar interaction as
View: Eye Point, around the center point of the object. The light point is displayed as a 3D crosshair during the operation.
The command
VIEWÞ View: Rotate View allows you to infinitely rotate the eye point around an axis.The rotation axis is chosen by clicking one of the mouse buttons: left for X, middle for Y and right for Z.
The rotation continues until some mouse button is clicked again. The rotation speed can be made slower by moving the cursor UP on the screen, and faster by moving the cursor DOWN.
Command
VIEWÞ View: Clipping allows you to define one or several clipping planes. These restrict the display of 3D objects so that only parts on one side of the clipping plane are displayed.After launching the command, you may choose the clipping plane direction by left mouse button for X, middle for Y and right for Z axis direction. To move the clipping plane, move the cursor UP and DOWN.
The clipping plane will cut things out from the side you are viewing the model; if you wish to clip from the other side you need first to change the view point to that side.
You may define up to six clipping planes at a time, two for each axis direction. The clipping planes will stay in their place even if you change the eye point, and they affect equally in shaded and wire frame modes.
To disable and enable the clipping planes , or to set their values numerically, click any KEY on the keyboard after launching the command.
The command
VIEWÞ Preferences controls various modes of display and shading.The curve accuracy parameter determines how much accuracy (number of points) is used to draw curves. It also affects the display accuracy of wire fame models by their surface curves, i.e., the patch boundaries. Each increase in the parameter's value doubles the number of points used.
The next parameter gives the maximum number of surface curves to be drawn on a surface in both of its (cross- and lengthwise) directions. To draw all the surface's patch boundaries, use a large value. Using a small value makes displaying faster, and saves system memory.
The shading accuracy option specifies how accurately surface models are faceted for shading, in the same way as
RENDERÞ Preferences. The alternatives are coarse, medium and fine.The double sided shading option specifies whether to shade triangles as two-sided regardless of their normal directions, or single-sided so that facets not facing the viewer are displayed darker.
The box move mode option is useful for working with very large objects or slow machines. When this option is set on, only the bounding box of the model is displayed under
VIEWÞ View: Eye Point.The PreView program creates fast shaded images and hidden line images of surfaces. The shading commands render all the surfaces that are shown on the screen at the moment.
Shading is available in software implementation (command
RENDERÞ PreView: Shaded View), as well as on hardware (command RENDERÞ GL Window: Shaded View).The accuracy of the shading is controlled with the
RENDERÞ Preferences options. You may choose an accuracy level between coarse and fine, or specify an explicit tolerance for triangulating the model. Another alternative with software shading is to use the so-called accurate shading, which operates on the actual surface representation, not triangulations.
This command renders the model as a shaded image in a separate GL window, where the surfaces and light points may be rotated in real time, among many other graphical functions.
Detail explanations on the GL window operation and its menu commands are given in the GL Window Operation Chapter below.
Works as
GL Window Shaded View, but renders the object as a wire-frame model, not shaded.
GL Window Operation and Commands
Window position and size
After you have given the appropriate
RENDERÞ GL Window command, the GL window pops up. Place the window to the desired location with the mouse, and fix the position with the left mouse button. Wait a while and the model gets rendered.If you want to change the window's size or shape, grab it with the mouse from its lower right corner. To get the window in full screen size, click at the large rectangle at the top right corner of the window.
GL pop-up menu
A pop-up menu appears in the GL window, if you press and hold the right mouse button down. (This is the convention used for all GL windows, while DeskArtes windows normally use the middle mouse button to access pop-up menus).
The GL window menus are generally two-level. Some commands are executed directly from the first level. For other commands, there is an arrow shown at the right end of the menu item. In this case, the actual commands are found in the second level. To get to the second level menus, move the cursor to the right end of the menu item.
Mouse functions
Most commands follow the mouse movement regardless of whether a mouse button is pressed down or not. There are some exceptions, however, which are explained below as necessary.
The execution of a command is finished by clicking the right mouse button again.
If you need to change the cursor location during some command, press the
Ctrl-button when moving the mouse: this way the mouse movement won't affect the image.
GL menu commands
The various GL functions are explained below.
• Move Camera
The command moves the camera around the model, just as the command
Additionally, if you hold the middle mouse button down, up-down mouse movement moves the eye point closer and farther away from the object.
End the function with the right mouse button.
Note: If your model is very large, or the machine is slow, you should set the
Move Mode (below) to the Box option. This gives much better interaction than waiting for the shaded image to be continuously updated.• Move Light
Moves a light point around the object, with similar interaction as with the previous command (Move Camera).
• Move Mode
This command controls how the shaded object is updated with camera and light movements. It has two options. The active option is displayed in gray, while the other option (which can be selected) is black.
Þ Model
Model is the default, updating the shaded image continuously as you move the mouse.
Þ Box
This option shows a box around the object as you move mouse, and reshades only after the moving is ended. The Box option is recommended with large models and/or slow machines.
• Pan
Move the focusing centerpoint with the mouse, like command VIEWÞ View Pan. However, you must press the mouse button down when drawing the panning line.
• Zoom
Zoom in or out, just as with command VIEWÞ View Zoom. Press the mouse button down when drawing the zooming window.
• Twist
Changes the tilt angle of the camera.
• Rotation
Þ X, Y, Z
Automatic 360 degree rotation around an axis. It may be interrupted at any time with the right mouse button.
Þ Infinite
This command rotates the shaded model infinitely on the screen. Depending on the cursor location, the model is spun slower or faster, and in different directions. The command is ended by clicking the right mouse button.
• Clipping
Normally invisible to the user, there are two clipping planes which determine how close and distant parts of the scene are rendered. These may be used effectively to cut out the front or rear parts(s) of the model, using the following options:
Þ Move near
Þ Move far
Change the clipping planes farther or nearer the view point with the up-down mouse movement.
Þ Double
Þ Half
To double or halve the mutual distance between the clipping planes.
• Turn two-sided shading on/off.
Normally all the facets are shaded as two-sided, regardless of their orientation. However, it is often necessary to check with faceted models that all the facets are consistently oriented. When two-sided shading is turned off, the incorrectly oriented facets will appear darker than the others.
• Save view
• Textures
These two commands do not have any significance for DeskArtes Rapid Tools.
• Hide axes
Disables the drawing of the coordinate axes.
• Save image
Stores the current image into a file.
• Lost in space!
To redraw the objects in the center of the window if you get lost.
• Done
This command aborts the GL window.
This command renders a shaded image of the model using software algorithms only.
The model is rendered from the eye point view, the same as used for wire frame displaying, using one light source.
If required, you may interrupt the shading at any time with
ESC or Ctrl-C.
Renders the surfaces shown on display with hidden lines eliminated.
Shows the image last rendered with software PreView, if it has meanwhile been erased from the screen.
Saves or recomputes the current software PreView image into a picture file, in the desired size and anti-aliasing accuracy. The image is rendered in full 24-bit colors (images computed on screen use 8-bit colors only).
The stored picture may later be shown with the command
FilesÞ FILE READ, by pointing at the pvpic file in question.The command asks for the following parameters:
• Picture name
Gives a name to the picture.
• As seen
With this option you may store the PreView image into a file just as currently seen on screen, with no additional computation. The image will then be stored as an 8-bit image without anti-aliasing, otherwise full 24-bit colors and the below options will be used.
• Picture width and height
If the image is not stored "as seen", you may tell a new size for it.
• Anti-aliasing level
The image accuracy may be controlled with the anti-aliasing level parameter. It tells how many samples are computed per a pixel in the final image, to smooth out the jaggies between neighboring pixels.
• Show image after save
With this option, the image automatically appears on the screen when its computation is ready.
Empties the software PreView memory: all surfaces will vanish from PreView, and the image buffer used by PreView is freed for other use.
The
Preferences parameters control the PreView image quality. They define the accuracy of the surface rendering. They apply equally to software and hardware PreView shading, as well as for computing hidden-line images.• Shading accuracy: coarse / medium / fine
Using these options, the surfaces will be converted to faceted models with certain tolerance and the shading is accomplished for faceted representation.
The triangulation tolerance value used depends on the size of the mode, and on the accuracy level you choose. For a particular object, each increase in the accuracy level, e.g., form coarse to medium, makes the tolerance four times smaller.
• Shading accuracy: accurate
An alternative to triangulation is to shade the surface exactly by scanning its geometric representation. This option is available for software PreView only.
Exact shading is usually (but not always) slower than faceted shading.
• Shading accuracy: explicit
This command results to triangulating the surfaces just as with the first three accuracy options, but you may define a numerical value for the tolerance. This value is asked as a separate parameter. It shows the actual explicit tolerance value which was last used to render a surface, and it may be changed into any desired value.
Do not use very small tolerances, like 0.001. The conversion to faceted form could then take very long times.
This menu contains commands that transform objects. Such commands involve moving, scaling, and rotating objects. The transformations take place around the object's fix point, which also can be set with the below commands.
The operation mode of the various transformation commands is controlled with the mouse buttons, as explained next.
General Functionality and Mouse Buttons
The transformation commands may be used equally on both 2D objects, and 3D objects. If an element or the root is selected for target, only the 3D objects within it are transformed.
All the transformation commands have different modes of operation, which depend on which mouse button or key is pressed with the command. The operations also depend on the object's dimensionality, and the viewing direction.
The following rules apply both to all 2D objects, as well as 3D objects when viewed from any axis direction:
• Left mouse button moves and rotates freely. Scaling is done uniformly in all axis directions.
• Middle button moves and scales in one axis direction only. The direction is determined by the first movement of the mouse. Rotation is not affected, but done freely.
• Right button transforms in some restricted manner. Moving is restricted to the grid snap values. Scaling is done in fixed scaling values of 0.8, 0.9, 1.0, 1.1, etc. Rotation is done in integer valued degrees.
For optimal speed with 3D transformations, only the object's bounding box is displayed. The transformation amount is displayed in the message lines while the transformation takes place.
Transformations with 3D objects in 3D view (not an axis direction), behave differently:
• Left mouse moves in the x direction, or rotates around the x axis.
• Middle and right buttons move and rotate relative to the y and z axes, respectively.
• Scaling is always done uniformly in the 3D view.
Finally, as an alternative to all the above cases:
• if you click at any key on the keyboard, instead of a mouse button, you will be able to enter the transformation values numerically.
Scaling and rotation is done around the object's fix point. If you move the object, the fix point moves with it. The above discussion, concerning the mouse buttons, applies with some exceptions to setting the fix point, as well.
This command moves the target object. See Chapter General Functionality and Mouse Buttons for details.
This command scales the target object. See aboveGeneral Functionality and Mouse Buttons for details.
This command rotates the target object.
If you apply numerical rotation with 2D objects, a positive angle rotates the object counterclockwise around the fix point. A negative value for the angle rotates the object clockwise.
The direction of numerical 3D rotations can be predicted by "gripping" the rotation axis with the right hand, so that the thumb points in the axis direction. The other fingers then point in the positive rotation direction.
See Chapter General Functionality and Mouse Buttons for further details.
This command mirrors the object to the other side of a line or plane that goes through the fix point.
You are asked as a parameter in which axis direction the mirroring should be done.
This command repeats the previously executed transformation. This way you could, for instance, rotate an object stepwise to the desired angle, by first rotating one degree and repeating this until the desired angle is reached.
This command moves the model to the positive octant of the model space, as it is typically required by the RP machines.
As parameters the command asks for a margin value in each of the coordinate directions, to move the object slightly away from the coordinate planes.
This command moves the center point of the model in the X and Y directions to the point selected by the user, and lifts the bottom level to the given Z value. The obvious application of this is to position the model to the center of the RP machine's workspace.
This command rotates the model to lie in the Z=0 plane on the selected facet. This can be of significant help to position the model correctly in the RP machine workspace.
This command scales a model from inches to millimeters, or the other way around. Whether to apply the scaling to the target object or to the whole model is asked as a parameter option.
The scaling, rotation and mirroring commands are executed relative to the object's fix point. It is shown as a cross on the screen when a transformation command is given. If the object is moved, the fix point moves with it.
You can set the fix point by clicking one of the mouse buttons after choosing the command. The principles explained in Chapters General Functionality and Mouse Buttons apply, with the following exceptions:
• Left mouse button sets the fix point freely at the pointed location.
In a 3D view, the fix point is placed on the target surface, at the point shown with the cursor.
• Middle button, when used with 2D objects, places the fix point to the nearest handle point of the target object. The nine handle points are located at the corners, side mid points, and the center of the object's bounding box.
In 3D view, the middle button places the fix point to the object's center. With 3D objects in an axial view, the middle button applies the grid snap value.
• Right mouse button always returns the fix point back to origin.
• Clicking any key instead of a mouse button pops up a dialog box, to set the fix point numerically.
This menu contains various commands for asking object dimensions.
This command pops up a graphical pocket calculator on the screen. Use it for any mathematical calculations you may require, for computing square roots of the dimension values, etc.
This command enables you to type text into a drawing.
Show with the mouse where you wish to place the text, and then type it. Use
backspace to delete characters, and return for line breaks.
This command gives you the possibility to edit the selected text. It shows a dialogue box with the text in it.
Text objects be selected with
SELECTÞ Object Pick, and moved with TRANSFÞ Object Move, like any other 2D objects. Text scaling and rotation is not possible, though.
The command gives the dimensions of the bounding box of the object, i.e., the greatest and least values of the three coordinate components.
This command prints out the center point of the bounding box of an object, i.e., the mean of the object’s extreme values.
This command reports the extents, i.e., the difference of the maximum and minimum values of the object's bounding box.
Dimensions
The system enters a "dimension" mode. A set of icons is displayed, and the user may choose any one of them until quitting.
Initially, a dialog box queries the user for the number of decimal digits to use when displaying the measurements. By default, the dimension values are displayed up to the first decimal.
The points where the dimensions are required are typically selected by using the mouse to draw a line that intersects the curve. If the line does not intersect any curve, the nearest curve end point will be selected.
After the dimension is computed and its text shown, the functions allow for placing the dimension text at a chosen location. You'll see the cursor change into a question mark: click at the LEFT mouse button if you wish to place the text, or any other button if you don't. If required, the dimension lines are automatically extended according to the placement of the text.
The available dimensioning functions are:
b
ounding boxComputes the horizontal and vertical dimensions of the curves. It does not ask for you to draw the intersection lines, just position the dimension lines where you want, then place the texts.
p
oint valueComputes the value of a curve point. Draw a line intersecting the curve, and place the dimension text.
d
istanceGives the distance between two points.
The points are selected one at a time by drawing a line with the mouse. Position the measuring line where desired, then place the text.
t
hicknessWorks like
d, but the intersection points are selected with just one intersection line, and the measuring line is drawn through the intersection points.The function is designed to find the dimensions in "crowded" parts of the model, when measuring lines produced with the
d function would not be expressive enough.h
orizontal distancev
ertical distanceThese functions work the same way as
d, but they give the horizontal and vertical distances between the indicated points.a
ngleComputes the angle between two straight lines, shown with intersection lines. The dimension lines and text may be placed either inside or outside to the dimensioned lines.
f
illet angler
adius of filletThese two functions do not have any significance with polygonal slices.
u
ndoErases the dimension lines and values last displayed.
ready (
write), store drawingExits the dimensioning mode and stores the dimension lines and texts into the DeskArtes workspace.
ready (
quit), don't store drawingExits the dimensioning mode without storing the drawing.
This command calculates the area of a faceted model or an element with several faceted models.
Calculates the volume of a closed faceted model or an element of them.
If the faceted model is not closed, the result of the volume computation generally gives the volume between the surfaces and the xy-plane.
This command allows for the display of dimensions in faceted models. Information about points, distances between points, and the radius defined by 3 points can be obtained.
The system remains in a "dimension" mode until a key is hit. During this time, each one of the mouse buttons can be used to perform one out of the three measurements described below.
The message window guides the user on how to use the mouse buttons:
• The LEFT mouse button returns information about a given point.
• The MIDDLE mouse button returns information about the distance between two points.
• The RIGHT mouse button returns information about the radius of a circle defined by three points.
• Hitting the keyboard exits from the dimension mode.
The dimension values are displayed on the screen at another location, chosen with the mouse.
This command gives the xyz-coordinates of any point on a surface, or a triangle vertex on a faceted model.
The required point is selected from the surface by pointing with the mouse. The values are displayed on the screen at another location, chosen with the mouse.
The
DESIGN menu commands produce or manipulate polygons, B-spline curves, and BŽzier curves, and produce various different kinds of surfaces.
This command allows you to input a 2D curve, by interactively placing the curve (control) points.
General Operation
To start the command, you must first place the eye point to one of the X, Y or Z coordinate axes. Use the X, Y Z buttons in the Setting Window for this.
If you have a curve set selected, the input curve will be placed in it. Otherwise the system asks a name for a new element, and creates a projection curve set to hold the 2D curve.
The representation of the input curve is determined with the
SettingsÞ REPS mode. If the object created is linear (a polygon), the points entered are to be the vertices of the polygon.If the object created is a B-spline, the points are taken as its control points.
• With
• With
SettingsÞ SHARP selected, all the B-spline control points are automatically made triple. This makes the curve appear sharp, just like a polygon.If the created object is a BŽzier curve, the input points are taken directly as the knot points for the curve. In other words, the BŽzier curve always interpolates the given points. Further,
• With
• With
SettingsÞ SHARP, the curve is tangent discontinuous at the knot points.
Input Functions
Once the command has been successfully launched, you'll enter into an input mode. You'll then define the curve points using various iconized functions. Note that none of the menu commands are not available in editing mode.
The functions are selected by clicking at their icons with the left mouse button. If you click with the middle button instead, a brief explanation of the function is displayed in the message lines.
Most functions have a shortcut, or a function key, assigned to them. A function key executes the function just as if the corresponding icon had been selected, only that they are faster to use once learned.
The following input functions are available:
new point (
middle)This function adds a point to the polygon. The point is positioned by clicking with the middle (or left) mouse button. The point may be moved until the middle mouse button is clicked again.
cancel point (
right)Removes the last point of the polygon.
n
umerical coordinatesAdds a point by giving its coordinates.
a
dd to coordinatesAdd a point by entering numerical increments to the coordinates of the previous one.
ready (
write): save the curve.This function finishes entering the polygon. If the last point in the polygon is near the first point, the curve will be closed (the last point will be exactly connected to the first one). Otherwise, the polygon will be open.
ready (
quit): don’t save the curve.Exits the curve input mode, but doesn’t save the curve.
With this command you may locally edit the target object curve. The command is operated with icon functions, similarly to the curve input command.
The same functions are used to edit polygons, B-splines, and BŽzier curves, with slightly different significance for each representation.
open/close curve (
B/C)These functions close an open curve and vice versa.
next/previous point (
+/-)Makes the point following or preceding the active point active.
select point (
left)Activates the point closest to the cursor.
right
pointWith this function it is possible to select multiple points for moving them simultaneously.
The function selects a point, called the "right point". All points between the active point and the right point are affected by certain move functions.
The right point is recognized by the functions
left (graphical move), x (axial move), n (numerical move), and p (projecting points). They affect all the points between the active and the right point.The right point is shown inside a double-box marker. Removing the right selection happens by selecting any point with left again.
move point (
middle)When a point has been made active, it may be gripped by clicking the middle mouse button. The point follows the cursor, and the curve changes shape according to the position of the point. When the middle mouse button is clicked again, the function is ended and the curve remains in its new form.
The function may also be used for moving multiple points, applying the "right" point selection.
c
opy pointThe function behaves slightly differently with B-spline and BŽzier curves.
With B-splines, it copies (duplicates) a point. The B-spline curve will form a rounded corner near the double point. If a double point is copied again, a triple point will result. The curve will then go through the point, where it will have a sharp corner.
With BŽzier curves, the function is creates a sharp corner on a curve, removing tangent continuity at the nearest knot point. After pressing a mouse button, the active point follows the cursor and all other points remain where they are. Stop moving the point by clicking the mouse button again.
i
nsert pointThis function adds a new point next to the active point, at a location shown with the mouse. The point is moved continuously until a button is clicked again.
The point is added to the side where the distance to the next point is smaller. If appropriate, the point is added to the end of a curve.
d
elete pointDeletes the active point from the (control) polygon.
n
umerical valueChanges the coordinates of the active point with numeric parameters.
The function may also be used for moving multiple points, applying the "right" point selection. In this case the function asks how much the points should be moved, not the absolute coordinate values.
g
rid moveThis function moves the active point continuously, keeping it at the grid snap points (c.f.,
SettingsÞ Grid: Snap).m
irror pointThe active point is mirrored with another point relative to an axis through the object's fix point. The mirroring direction (horizontal or vertical) is chosen by the system, as it considers most appropriate.
The reference point (which should be matched with mirroring) is selected with the mouse after choosing the function.
As a useful special case: if you select the active point itself as the reference point, it moves directly on an axis through the fix point.
l
evel pointThis function aligns a point with another point, parallel to one of the axes. The reference point is chosen the same way as with the mirroring (
m) function. The alignment direction is figured out automatically by the system.A useful special application: if you align a point twice with another point, it is aligned in both directions, i.e., set equal to the other point.
u
ndo previous actionAny edit mode change may be canceled by clicking this icon (if available). Give it immediately after the erroneous action. Actions preceding the previous one cannot be canceled (except by exiting edit mode with
q, which cancels all changes).re
fresh screenErases the screen and redraws the contents. This may be needed when irrelevant information has been displayed on the screen.
ready (
write): save changesExits edit mode and saves changes. The original curve is replaced with the edited curve.
ready (
quit): reject changesExits edit mode without saving changes. The original curve is left unchanged.
This command creates a polygonal curve, with the number of edges center point and outer radius defined by the user. The curve type is defined with
SettingsÞ REPS.
This command creates an open arc of a circle. The curve type depends on
SettingsÞ REPS.The required parameters are the start and end angles of the arc, its center point, and the number of knot points to be used for the arc.
This command creates a circular curve. You will be asked the radius of the circle, its center point, and the number of knot points.
The accuracy of the circle depends on the number of points. Given the same number of knot points, BŽzier circles are more accurate than B-splines.
This command produces an offset to the target curve. The offset curve follows the shape of the target curve, at the specified distance.
To which side the of the original curve the offset is produced depends on the sign (positive or negative) of the distance.
The accuracy of the offset curve depends on offset distance, as well as the number of control points used for the original curve.
This command creates primitive surfaces in faceted form.
To create a primitive in its own element, separate from the others, you may give command
OBJECTÞ New before creating the primitive(s). Alternatively, you may tell the command to place the primitive in a new element as one of the parameters when creating the primitive.The available primitive types are:
• Plane
• Box
• Sphere
• Cylinder
• Cone
• Torus
As parameters, the primitives are given dimensions (e.g. a cylinder’s center, radius, and height), and the axis direction (x, y, or z) into which the primitive is created.
In particular, a plane will be created with the same choice of parameters as a box, when the maximum and minimum values for one side of the box are given equal values.
This command extrudes the projection curve(s) into surface(s), in the selected projection direction.
The start and end coordinate values of the extrusion will be asked as parameters. The default values are such that the created surface will be slightly (1.2 times) broader than the other objects in the system's workspace altogether. In this way, it is easy to define tool surfaces, to cut out the shape of the projection curve from any other model within the system.
As another parameter it is asked, whether the extruded surface(s) should have caps at the ends, in effect, closing the surfaces into solids. The alternative is to leave the surface ends open.
As a side effect of extruding, the previous surfaces and faceted models within the element will be assumed to be redundant and they will be deleted. This feature also applies to the commands
Surface Rotate and Build. To preserve the old surfaces, make a copy of the element with the command OBJECTÞ Copy before extruding.
This command rotates the projection curve around the horizontal or vertical axis of the selected projection direction. It is also possible to rotate a curve around an axis going through the projection curve's fix point, not always at origin. These options are asked as parameters for the command.
This command builds a surface using one or two projection curves and one section curve, according to the rules of the DeskArtes Industrial Design System. The projection curves must be B-spline curves: it is not possible to build a surface with BŽzier curves.
There may be either two or three curves defined in the projection set. The last curve there is always assumed to be the section curve.
If there is just one projection curve defined before the section curve, the resulting surface is in effect a sweep of the section curve along the projection curve.
With two projection curves before the section, the result is a scaled sweep between the two (first) projection curves.
The choice of target object and the side effects of the command are similar to those of the previous ones. In particular, the old surfaces and faceted models within the element will be deleted when the command is performed.
This command defines the triangulation accuracy to be used with the commands
Extrude, Rotate and Build.
This command checks for self-intersections within trim curves, and cuts the loops away if there are any.
The command can be performed either on a trim curve set, a surface, or an element. The problematic trim curves are separated in a new element, and colored differently. Messages of where the errors were found are printed in the command window from which DeskArtes was launched.
This command looks for trim curves which intersect each other, and separates and reports them (c.f. command
Check: Looping Trims).
This command removes duplicate trim curves from the surfaces, and separates and reports them (c.f. command
Check: Looping Trims).The user may choose if one of the multiples is automatically deleted. It is recommended that the first time this function is applied to a model that the multiple trimming curves not be deleted.
The command
Check: Multiple Surfaces goes through an element of surfaces, and looks if there are same surfaces defined more than once. If so, the program separates the equal surface(s) to a new element.The equality test is based on comparing the bounding boxes of the surfaces, within a user-definable tolerance.
This command automatically executes all the previous four checking commands in one call.
This command works just like the following one (
Surface Triangulate), except that it does not triangulate the model, it just reports the gaps which would remain in the model with given parameters. Thus, it is faster to use if you first wish to experiment with the gap elimination parameters before triangulating.The parameters are (see command
Surface Triangulate below for the parameter details):• Trim curve accuracy
Tells how accurately the trim curves are presented.
• Size of gaps to fill
Tells the size of the gaps the program should look for.
Once you've found a suitable parameter combination which eliminates all (or most) of the gaps, proceed to the next command to actually triangulate the model with the same choice of parameters.
This command calls the vda2tr program, and triangulates the surface model with given parameters:
• Triangulation accuracy
Tells how accurate the triangulation should be, i.e., the maximum deviation between the triangles and the actual surfaces.
• Maximum triangle edge length
This parameter forces all facets in the resulting triangulation to have a maximum edge size below the given value, thus producing a more uniform triangulation than just applying the deviation tolerance.
The particular use of this feature is found when the triangulated model is later to be offsetted (c.f., command
• Trim curve accuracy
Tells how accurately the trim curves are approximated when computing the triangulation. With small values, extra points are added to the trim curves. This helps with gap elimination, but produces more triangles. As a rule of thumb, a value of about 1/10 of the triangulation accuracy is generally a good choice.
See also the following command
Reduce Trims for how to reduce the number of points on the trim curves.• Size of gaps to fill
Tells the size (width) of the gaps the program should look for. The value should be reasonably close to the actual gap sizes. If the given value is too small, large gaps will not be detected.
• Orient normals
If you choose not to orient the normals it saves some time in triangulation, but then you must later remember to pass the model through command EDITOR
Þ Faceted Repair before any further processing.
This command reduces the number of trim curve points of a surface or within a complete element, according to a user-given 3D tolerance.
When reading surfaces from other systems the trim curves may be presented too accurately to be practical. Normally, each point on a trim curve will result to a triangle in the faceted model. Reducing the number of trim points leads to more efficient triangulations.
This command inverts the surface, i.e., it trims away the originally untrimmed parts (faces) of the surface, and makes the originally trimmed parts visible.
This command calls the
tr2stl program, and shows all possible errors in the model. The command only asks for one parameter, that is, Check triangle intersections (see below).
This command passes the triangulated model to the
tr2stl program, which corrects the possible errors in it. The command asks for the following parameters:• Size of gaps to fill
Specifies the size, i.e., the maximum extent of the gaps the program should look for. This works a bit differently from the
Holes larger than the given gap size won't be filled. With too large values, on the other hand, the program may attempt to connect wrong triangles to each other.
• Gap fill method
The options aremove vertices and fill between. Move vertices does not add new triangles, but it moves the vertices of existing triangles around a gap to match the ones close to them.
With this option, the gap size parameter specifies the height of the gap, not the diameter. The command is also capable of closing, letter "O" shaped gaps, which previously had to be done interactively.
In summary, this new option works very similarly to the command
FACETORÞ Surface Triangulate, but for faceted models instead of surface models.The option fill between fills with new triangles each gap whose largest diameter is smaller than the given gap size.
• Check triangle intersections
With this option chosen the program reports all triangles which intersect with each other. As this may be quite time consuming, it is provided as a separate option.
• Separate all offending triangles
With this option you may tell the system to separate all triangles which seem to cause problems. If offending triangles are found, they are placed in a separate
Faceted object.The recommendable way to use the
Repair command now is to first use the move vertices option to close all thin gaps in the model. Only after the actual gaps have been closed this way,. the fill between option may be used to close actual holes in the model.
This command combines the target element with the next element in the object list, e.g., to merge a model to its offset.
This command takes a faceted model as target, and finds all separate parts in it. It uses the tr2stl program. The parts are stored in separate elements. You could use this, for instance, to separate floating triangles from the model, or to separate the offset from the original model.
This command takes a faceted model as target and splits the model along the parting line. Produces the upper and lower part of the mould and the parting line.
The parameters for this command are:
• Split into subparts
If this selecion is set to YES, mould upper and lower parts are generated.
• Create parting line
If this selection is set to YES, parting line is generated.
This command shows the normal directions of a triangulated model, and asks if the direction should be changed.
It's generally a good idea to use this command before storing the STL file for manufacturing. For a correct STL file, the normals should always point outwards from the solid.
This command will deletes all triangles with vertices outside a given cube centered at the origin. The parameter is the edge length of the cube.
Consult the section Corrupt STL Models in Processing STL Models for more information.
This command finds an individual triangle, as you point at its three corners with the left mouse button.
The command can also be used to select several triangles at once. For this, point at the desired triangle vertex. The selection method depends on which mouse button you press:
• with the middle mouse button, all triangles which touch the box will be selected.
• with the right mouse button, only those triangles which are completely inside the box will be selected.
After this, a box appears around the selected point. Press the mouse button again, and change the size of the box to define the selection area.
Finally, choose from the parameters what you wish to do with the selection: delete the triangles, separate them into a different model, or just color them differently from the rest.
This command adds a new triangle to a faceted model. Point at any already existing three corners of the other triangles with the mouse, and a new triangle is generated to fit there.
This command deletes the chosen triangle from the model. The removed triangle is colored as yellow (not erased).
You may use these last three commands to get rid of such small errors in the model, which postprocessing is unable to fix. For example, if you have intersecting triangles in the model, first select and delete them, then use command Faceted: Postprocess to fill in the gaps.
This command provides a method for removing and separating multiple triangles within a selected area on the screen.
The command asks you to draw a polygon. Use the left mouse button to place the polygon vertices, and middle button to cancel a point. You may close the polygon either by clicking at the right mouse button, or placing a point very close to the polygon's first point.
Finally, choose from the parameters what you wish to do with the selection: delete the triangles, separate them into a different model. All triangles which are located completely inside the polygon will be affected.
This command automatically fills a closed 3D polygon, e.g., a gap curve with triangles.
The resulting triangulation is stored in the next object after the selected curve set. You may move it from there into the complete faceted model using the commands
OBJECTÞ Cut/Paste and Merge.
This command calls the stlcut program. In effect, it cuts the triangulated model into smaller pieces, for the purpose of the parts to be manufactured separately.
The command first asks for the following parameters:
• Cut direction
The model may be cut with a plane (or planes) orthogonal to one of the x, y, or z axes. The plane coordinate values are given with separate dialog boxes, as explained below.
Note: you may also set the cutting plane graphically by defining a clipping plane with command
• Create solid
Specifies if the result parts should be solid, or left open where cut.
After these are given, the following parameters are asked for each cut plane separately:
• Cut value
The cut values in the chosen axis direction are given one by one, in increasing order. The first default value tells the minimum extents of the model.
• Ready
Select this option when all the cut values have been given.
The normals of the cut parts are automatically oriented correctly, so you don't need to postprocess the result separately. The same also applies to Offsets, Primitives, and Boolean combinations.
Using the trbool batch program, this command creates a Boolean set operation between two faceted models, i.e., cuts one with the other and joins the results.
Select one of the faceted models as target before giving the Boolean command. The system then asks you for the other model's element name, as shown in the object list. (To avoid typing the name yourself, if you only have two elements displayed on the screen, the system will propose the other element's name as default.)
Next you'll choose how the resulting model is composed, the options being:
• union of this and other
• subtract this from other
• subtract other from this
• intersection of this and other
• split in four parts
The first four options apply generally for solid models, and should be easy enough to understand. The last option is intended especially for non-solid (open) models, producing all four components resulting from the intersection between the two models.
Note that with the first four options, the component models' normals must be oriented correctly (postprocessed) for the Boolean command to work correctly.
This command reduces the number of triangles in a faceted model, according to the user given parameters.
The command first asks which Reduction Method should be applied. The choices are:
The Edge Length method only modifies those triangles whose shortest edge length is below the given value. It asks for the following parameters:
• Short edge length
Those triangles whose shortest edge length is below this value will be removed (see next parameter, though).
• Min height ratio:
No resulting triangle will be allowed to have a ratio between the shortest and longest edge below this parameter value. This parameter must be enabled with a separate option in the dialog box.
• Multiple pass
When enabled, this option does a more efficient job in reducing the number of triangles but it takes more time than the default "single pass" mode.
The parameter value specifies that the reduction process should be repeated until the reduction percentage gets below the given value.
The Tolerance method is more sophisticated. Additional to the above parameters, it asks for the following:
• Tolerance
Specifies the maximum allowed deviation of the reduced model from the original one.
• Maximum angle
As the program combines neighboring triangles together, this parameter tells that triangles whose normal angle is greater than the given maximum value must not be combined. This way sharp details will not be disturbed.
• Max edge length
No reduction will be applied to such triangles that have a triangle edge longer than this parameter value.
• Grid
This parameter only has significance if the command is used in combination with the
The number of parameter options is quite large. However, for typical applications it is sufficient to modify just the couple of first mentioned parameters with each method, and leave the rest to their default values.
Refine
This command refines the faceted model into smaller facets. It will split all the triangles that have edges larger than the specified value. If the splitting creates triangles with edges longer than the desired length, they are split as well. Therefore, the number of triangles may grow considerably depending on the tolerance given.
The dialog box that is displayed gives an indication on how much the result grows. If you see that the result is far too large for practical use, you may cancel the operation and try again with a larger edge length value.
The resulting triangulation will contain triangles with a better aspect ratio than the original model.
As one application, the refinement of an STL model can improve the results of the
Offset command. If the original model has very large triangles attached to areas with very high curvature, refining the model will improve the offset model.Invoking the command pops up a dialog box for refinement parameters:
• use average edge length
In this case, you do not need to specify any numerical value for the maximum edge length. The program will compute the average, multiply it by Ã2 and use the result as the maximum edge length. The factor Ã2 is a round-off value.
• maximum edge length
If you choose this option, you must then specify a positive numerical value for the maximum edge length.
This command creates an offset to the triangulated model, i.e., another triangulation which is a constant distance apart from the original one. Internally, it uses the troffs program. The command takes the following parameters:
• Offset distance
Specifies the desired wall thickness.
• Offset direction
This tells whether the offset should be created to the inside or the outside of the model. The "normal" direction is indicated with small arrows as the command is started. The default offsetting direction in "opposite", or "inside", which is more suitable for solid models.
• Round corners
If this option is set to YES, the program will produce rounded corners at outward sharp corners of the original model. Otherwise sharp corners are created to the offset, too.
• Remove offset self-intersections
This option automatically removes all possible self-intersections within the offset.
• Auto clean-up
This option attempts to automatically clean the offset of all other kinds of possible problems, such as problematic corner areas, inverted triangles, etc.
Note: Creating the offset is a difficult computational task, taking lots of computer time. Also, the results should be carefully checked before manufacturing. In particular, offsetting may find difficulties if the model contains sharp corners with large angles, and/or if too large offset distances are used. When necessary, use triangle picking and deleting to get rid of erroneous parts, and postprocess the model again to correct it.
This and the following three commands are available to trim combine different curves with each other, for instance to remove extra parts of slice curves or to join open slice pieces together.
Command
Cut Two cuts two curves with each other. The curves to be cut must belong to the same curve set. They are picked from the graphics window, after the command has been given.The command is only able to cut BŽzier curves and polylines. B-spline curves are automatically converted to BŽzier form for cutting.
This command joins two curves into one. The curves to be joined are picked from the graphics window.
If it is not obvious from the geometry of the curves, the command asks if the result should be closed, or left as an open curve.
The command cuts all the curves in a curve set with each other. As the result, the curves are split into several curve pieces, which end at the intersection points of the curves.
As with command
Cut Two, B-spline curves will be converted to BŽzier when cut.
The command joins all the curves in a curve set with each other, trying to form closed curves out of the separate open ones.
Those curve pieces which could not be joined into close curves will be colored with the last vector color (yellow), for the user to distinguish them better.
This command generates a sliced representation of the triangulated model, using the tr2slice program. The slices can then be fed to control the Rapid Prototyping machine directly, once converted to the appropriate slice format. Command
FILE WRITE/data transfer allows for storing the slices in the SLC, CLI, SLI, DXF, IGES and VDA formats.The model must be sliced separately from its possible support structures. In other words, the corresponding slices must be placed in two different elements, which must then also be written into two separate files.
The parameters for slicing are:
• Slice distance
Specifies the distance between the slices. The slices are computed in the z direction, from bottom to top.
• Gap tolerance
If the original model contains gaps, this option allows for closing them in the slicing stage. All gaps smaller than the gap tolerance will be closed.
• Data reduction tolerance
Specifies the tolerance used to reduce the number of points in the slices. All polygon vertices which lay between two vertices and nearer than given tolerance value to the connecting segment of the two vertices are removed.
Don't use too large gap tolerance values, as they may result in closing the gaps in a wrong way. Instead, you may close the gaps later on with the command
SLICESÞ Close Gaps, using progressively larger values. See also the other slice editing commands below.When the slicing is done, the slices are loaded into the DeskArtes workspace. Outer contours are displayed as white, and inner ones as blue. Red color denotes open slices, i.e., erroneous parts which can then be further processed with the commands below.
This command slices the selected part element and given support element and stores the slices in disk files either in CLI or SLI format.
The parameters for slicing are:
• Part
Specifies the name of the part element.
• Support
Specifies the name of the support element.
• Slice distance
Specifies the distance between the slices. The slices are computed in the z direction, from bottom to top.
• Data reduction tolerance
Specifies the tolerance used to reduce the number of points in the slices. All polygon vertices which lay between two vertices and nearer than given tolerance value to the connecting segment of the two vertices are removed.
• Output format
The sliced can be stored either in CLI or SLI format.
Pressing OK button starts the command. Each element given in the dialogue box is sliced and the result is stored in disk files. The files are named according to the selected format. The post fix for CLI format is '
.cli' and for SLI format '.sli'. The '.stl' or '.sup' post fixes of the elements are replaced with these strings when constructing the slice file names of the part and the supports.
This command closes all gaps in the slice(s) which are smaller than the given tolerance.
This command changes the direction of a slice, from outer (white) to inner (blue) or vice versa.
This command allows you to edit a slice in 2D. Its use is similar to command
DESIGNÞ Curve Edit. See the corresponding part of this Manual for the function references.
This command enables you to scan the slices on the display, displaying the separate slice layers one by one as you move the mouse up and down.
How the slices are shown depends on the mouse button you press when you move the mouse. The left mouse button erases all other slices except the active one. Pressing the middle mouse button keeps all the slices on the screen, coloring them gray as you move from slice to slice.
A fast movement of the mouse allows you to get the cursor from top of the screen to the bottom, or vice versa so that you'll have more space to move the mouse again.
This command finds any open gaps in the sliced model. Such slices would most typically produce errors in the RP process, and they should either be closed (using command
Slices: Close Gaps), combined with other polygons (using commands TOOLSÞ Curves: Cut and Join), or removed altogether (with command OBJECTÞ Delete).The command always finds the next open slice within the element after the target object. Once all open slices have been removed, the command just reports this to be the case.
This command allows you to specify the maximum number of slices that are displayed at a given time. You can still examine and scan each slice, but it is not generally usefull to display all the slices at once on the screen.
This command computes the support structures to the selected faceted model with DeskArtes Support Generator. Its use and functionality is described in the Section Support Generation of this manual.
This command enables the user to edit Support Generation parameter files. Its use and functionality is described in the Section Support Generation of this manual.
This command provides an interface to some third parties' support generation software. Further information is provided on request.
Overview
In the multi-user installation no additional account is created for the program. The installation tape can be loaded in any directory of the system and then the environment of existing user accounts is modified so that they can run the program. In the multi user installation it is also possible to create local model databases for the selected user accounts, but this is normally not needed for Rapid Tools.
If you don't want to use old user accounts as DeskArtes Rapid Tools users, create the needed new user accounts first and then continue with the installation.
If you are going to define several user accounts to use the same central model database and wish that they can access each others' models, put the accounts and also the program owner account to the same group. See User accounts and groups under the heading Troubleshooting.
Example installation
The user accounts defined here as DeskArtes Rapid Tools users are assumed to use
csh, tcsh or compatible as their login shell.In this example the installation directory (dahome) is chosen as
/usr/people/dahome, the program owner account is da and the user accounts configured to use DeskArtes Rapid Tools are user1, user2, user3 and user4. A local database is created for accounts user1 and user3. Login as
Find a file system with enough space for the installation with command
df
Select a directory from that file system and make it the current directory.
cd
/usr/people
Create a new directory for the installation.mkdir
dahome Read the DeskArtes installation tape into the da directory
cd dahome
tar xv
Start the DeskArtes installation program with the command ./dainstall.Dainstall first asks the name of the customer (your company). This is a text string, which will be shown in the title bar of the DeskArtes Rapid Tools main window. So key in your company name, e.g.:
Donald & Co. Design Office Ltd.
You can change the name later by editing the file
dahome/System/.customerThe second question is about the installation type which is
2
for multi user installation.
Then the name for the program owner account is asked. Any existing account, e.g.,
da if such user exists, will do here.Note however that if you are going to use one central model database for the DeskArtes user accounts, give an account that belongs to the same group as them.
Dainstall then asks the accounts which are going to use DeskArtes. Give the account names separated with spaces. The accounts given here must already exist.
user1 user2 user3 user4
The next step is to define the accounts to have local model databases. Give account names separated with spaces, or if you want to have one central model database for all user accounts just press Return (the default is none).
user1 user3
Then dainstall asks the accounts whose X window manager resource definitions are updated for DeskArtes use. Normally these are the same accounts defined as DeskArtes users earlier. If you don't want to change the X window manager settings of a user account, just leave out that user from the list.
user1 user2 user3 user4
Logout.To start using DeskArtes Rapid Tools, log in with any of the user accounts you defined in installation.
Launch the DeskArtes Rapid Tools with command
rt, rapids or rapidsgl
from any command window.
In case of any problems see the following chapter: Installation troubleshooting.
Reading the tape
When the tape device is connected directly to the machine which you are installing on, there should be no problems in reading the tape with command
tar xv.However if the tape device you are using is not defined as the default device, you have to add the device name to the tar command. The command would then be
tar xvf devname, where devname is the device name of the tape device.The default device the tar program tries to use when no device is given in the command line varies on different platforms. Usually it is either device
/dev/tape or the value of the environment variable TAPE.The device names for the tape devices also differ on different platforms. For example, on SGI machines, the device names are something like
/dev/rmt/tps0d5, where the last number is the SCSI id number of the device. On Sun«s, the device names for the tape devices are typically like /dev/rst0 and on HP /dev/rmt/0m. Also in these names the last number varies. If you can't find out the valid device name from the documentation of your machine, consult your hardware vendor.If you are reading an SGI version tape (QIC) with another vendor's tape device (Sun, HP, etc.) you will most probably have problems with tar saying something like: "directory checksum error "or "this appears to be byte swapped device". The reason to this is that traditionally SGI QIC tape devices swap all bytes when writing the tape. In such cases, try the following command, assuming that
/dev/tape is the valid device name of your tape device:dd
if=/dev/tape conv=swab | tar xvf -The command above works also when you are reading a Sun or an HP version tape with an SGI tape device. However, in that case you can also use the non-byte swapping tape devices on SGI. Those devices are recognized as having suffix "
ns" in their device names. The actual commands are thentar
xvf /dev/tapensif the default tape device
/dev/tape is defined ortar
xvf /dev/rmt/tps0d5nsif the normal device name of the tape device is
/dev/rmt/tps0d5.
Reading the tape over network
When installing over network connection, which here means that the tape device is connected to another machine at the network, there are some additional things to consider.
Let's take an example situation where you are installing to
machine1 and the tape device is connected to machine2. Then if machine2 has an account for username guest properly configured, you can read the tape from machine1 with command:tar
xvf guest@machine2:/dev/tapeIf the guest account doesn't exist at
machine2 or the previous doesn't work for other reasons try the following. First add the line:machine1
rootto the file
/.rhosts at machine2 using some text editor (vi, Emacs, etc.). If the file doesn't exist create it.Check the permission bits of the
/.rhosts file with the command:ls
-l /.rhostsThe first column in the output of the command should be exactly the following:
-rw-r--r--
If the permissions are set otherwise you can change them with the command:
chmod
644 /.rhostsThen read the tape from
machine1 with the command:tar
xvf machine2:/dev/tapeThis should work if the tar command at
machine1 accepts device names which contain machine names. Otherwise, try the command:rsh
machine2 dd if=/dev/tape bs=20b | tar xBfb - 20If either of the machines is SGI and the other is not, and you are reading a QIC tape, there might also be the byte swapping problem. In that case, you must add the
conv=swab option to the previous command. Then the command would be:rsh
machine2 dd if=/dev/tape bs=20b conv=swab | tar xBfb - 20
User accounts and groups
In the single account mode,
dainstall tries to create a new user account to the system. In some situations, for example when Network Information Service (NIS¨) is in use, this can't be done. Then you can create the user account manually and run dainstall again.You can create the user account either by editing the
/etc/passwd file or with some graphical system administrator tool (UserManager, smit etc.), but remember to set the installation directory (dahome) as its home directory and /bin/csh as its login shell. When you then run dainstall and it asks the program user account, give the user name of the account you created. Because the given account now exists, dainstall uses it instead of trying to create a new one.In the single account mode,
dainstall suggests a pathname for the install directory when creating a new user account. In many cases this path is correct but if you are using Network File System (NFS¨) in networked environment and the install directory resides on a disk mounted by other machines, there is usually a global path with which the other machines access that directory. In this case, you should give this global path to dainstall instead of the suggestion.If you have defined several user accounts to use the same central model database (the multi-user installation) and they have to be able to handle common models, you have to create a new group for them. Those user accounts and also the program owner account must be then defined to be members of this group. Finally the groupid for those accounts has to be set to the groupid of the created group.
To create a new group edit file
/etc/group
with any text editor (vi, emacs, jot etc.). Note that you have to login as
root to be able to edit that file. Add then for example the following line to that file:deskartes::53:da,user1,user2,user3,user4
Here the first field is the name of the group and the third field is the group id number. These can be selected freely but they must not be the same as in another group definition in the file. After the groupid the last field is a comma separated list of all user accounts belonging to that group.
To set the groupid for user accounts edit file
/etc/passwd with any text editor. Note that you have to login as root to be able to edit that file. In the file each line defines a user account.da::1114:53:DeskArtes:/usr/people/da:/bin/csh
The fourth field in the line is the groupid of the account. Change that field to the groupid of the group created above, for all the user accounts listed in the group definition.
When the group is created and the group id numbers of the accounts updated, give the command:
chgrp
-R deskartes /usr/people/dahomewhere
deskartes is the group id or name of the newly created group and /usr/people/dahome is the installation directory (dahome).
Running the X Window System
In some environments and/or configurations, the X Window System is not started automatically when you log in the system. In such cases, you have to first start the X Window System with the proper command before launching DeskArtes. The most common commands to do that are
openwin on Sun environment and xinit on IBM machines.In some versions of Sun environments the default is to turn on the Xauthority mechanism when starting X. If you have problems in opening new windows and there appear error messages complaining about authority restrictions on the console, try to start the X Window System with command:
openwin
-noauth
Rapid Tools doesn't start up
The most probable reason to start up failure is that the execution environment hasn't been set up correctly. This setup is done from file
.cshrc in the users' home directory. Note: It is assumed that the user accounts use csh or compatible when running DeskArtes Rapid Tools. The file .cshrc should contain a line:source dahome/System/DA.cshrc
Here dahome is the path to the DeskArtes installation directory. Note: If the single account installation was used the dahome above can also be only tilde "
~" which correctly refers to the home directory of the user account.If that line exists in
.cshrc and is correct but the program still fails to start up, you should check the environment variables. All the environment variables from the current shell and their values can be printed with command env. The most important variables regarding to DeskArtes startup are the following:
DAROOT |
Should be the path to the install directory dahome. |
DA_SYSTEM |
Should be the path to dahome/System. |
DA_RESOURCE_DIR |
Should be the path to dahome/machine/displaytype, where displaytype is one of the subdirectories of machine: indigo, iris4d, hp, sun, rs6000 etc. depending on the X display. |
PATH |
should contain among other paths: dahome/bin/bin.$HOSTTYPE, dahome/bin/bin.Script and dahome/bin/aux.$HOSTTYPE, where $HOSTTYPE is one of the following: irix5, sun4, solaris2, hp or PowerPC depending on the platform. |
If the error message in startup failure says :
Cannot open display, you probably don't have the X Window System running, see Running the X Window System above. If you are in a networked environment another possible reason to this is that you are logged in remotely over network and not allowed to use that display you are trying to. In such case check the value of the VIEW environment variable with env command and give command xhost + from the machine whose display the current value is.If you are in a networked environment and nothing appears to the screen even if DeskArtes doesn't complain anything at the startup, your VIEW variable may be set to use the display of another machines. Terminate DeskArtes with the "kill" character, normally
Ctrl- C or Del, and check your VIEW variable. You can see the value of your VIEW environment variable with env command again. Its value is typically :0.0 or hostname:0.0, where hostname is the name of your machine in the network.
Rapid Tools starts up as demo version
If DeskArtes Rapid Tools can't read a valid license file while starting, it starts up as demo version. With the demo version of the DeskArtes Rapid Tools you can only run the summary demo, not do anything useful.
If you have purchased a license, or have an evaluation license for certain time period, and the program still starts as demo version, check the following.
There is a license file in the directory dahome/
System, with name dalic.sysid. Here sysid is the system identification number which you can get with the following commands on different platforms:Silicon Graphics :
sysinfo -sSun SPARC : hostid
Hewlett Packard : uname -i
IBM RS6000 : uname -m
If the name of the license is wrong you can try to rename it with command
mv oldname newname and then start DeskArtes RApid Tools again. If this doesn't help or if the license file is missing, ask your distributor for a new license.For the Silicon Graphics and HP platforms there is a alternative license system (FLEXlm) available.
The FLEXlm license file is also in the directory dahome/
System. The license file has name flex.sysid. Here sysid is the system identification number which you can get with the following commands on these platforms:Silicon Graphics :
echo `sysinfo -s` 16o p | dcHewlett Packard : echo `uname -i` 16o p | dc
The system automatically checks for both types of licenses in the startup. However you can force the system to only check one type of license with commands
setenv DA_LICTYPE flexlm
setenv DA_LICTYPE dalic
To return back to the automatic license check mode, give command
unsetenv DA_LICTYPE
Keysym errors at startup
If you are running DeskArtes Rapid Tools on Sun platform and the command window shows lots of error messages like
"translation table syntax error : Unknown keysym name : osfHelp ... found when parsing ' <Key> osfHelp: Help()' "
do the following. You have to be logged in as root to do this.
Check if there is a directory /usr/lib/X11 in your system and if not create it with command
mkdir
/usr/lib/X11Copy the file dahome/System/XKeysymDB to that directory with command
cp
dahome/System/XKeysymDB /usr/lib/X11Here dahome is the DeskArtes Rapid Tools installation directory.
When you start DeskArtes Rapid Tools again those error messages should not appear any more.
Installation tips for system administrators
Using Korn-shell (ksh)
Everywhere else in this manual it is always suggested that the user accounts running DeskArtes Rapid Tools are using C-shell or compatible as their login shell.
However the system distribution contains all the needed startup files also for the Korn-shell, so it is possible to setup a ksh user account to be able to run DeskArtes Rapid Tools.
The dainstall however always creates user accounts with csh as login shell, so you have to create the ksh user account for Rapid Tools manually before running dainstall. Also the dainstall must be run with -k option to make it to update the ksh startup files also. When dainstall asks the user account, give the ksh account you created and it will then use it instead creating a new one. Otherwise the installation goes like with csh.
A ksh-account for DeskArtes Rapid Tools use can also be set up with the manual installation, see the Installation without running dainstall.
Installation without running dainstall
The dainstall program does many things automatically but there is nothing special in that program. So if you have enough knowlege about UNIX-like operating systems and want to have better control of what is happening during the installation you can as well do the same things manually.
To make the single account installation manually do the following:
Create separate user account for the system
Edit /etc/passwd and add line.
da::1114:5401:DART:/usr/people/da:/bin/csh
If you want to use Korn-shell replace /bin/csh with /bin/ksh.
Create separate group for the system
Edit /etc/group and add line.
deskartes::5401:da
Create home directory for da user accountmkdir
/usr/people/da
Read the DeskArtes Rapid Tools installation tape into the da home directorycd /usr/people/da
tar xv
Edit the file System/.customer to contain the customer name you want to be shown in the program title bar. Update the DAROOT directory path definition in the beginning of the file
System/DA.cshrc to point to the home directory of dasetenv DAROOT /usr/people/da
For the ksh the corresponding file is
System/DA.env and the lineexport DAROOT=/usr/people/da
Change the owner and the group owner of the whole da home directory to da and deskarteschown -R da /usr/people/da
chown -R deskartes /usr/people/da
To start using DeskArtes Rapid Tools, log in with the da user accoust you just created and then launch the Rapid Tools with command
rt, rapids or rapidsgl
To enable other user accounts to run DeskArtes Rapid Tools, like in multi-user installation, you need to do the following two steps for each account.
Add the following line into the C-shell startup file
source /usr/people/da/System/DA.cshrc
For the ksh the corresponding file is
.env and the line. /usr/people/da/System/DA.env
NOTE: To get
.env executed when starting ksh there has to be the following line in the .profile file of the userENV=$HOME/.env
Change the X window manager settings suitable for DeskArtes Rapid Tools use, if possible. The Rapid Tools GUI was designed to work with the window manager mode where the keyboard focus follows the mouse, so this is the most important setting. The other recommended settings for the SGI and Motif window managers are found in file.Xresources
For the HP VUE environment the recommended settings are found as lines beginning with
vuewm in file.vue/sessions/current/vue.resources
For the Common Desktop Environment (CDE) the recommended settings are found as lines beginning with
dtwm in file.dt/sessions/current/dt.resources
However some window manager settings, like the keyboard focus policy, can be set in VUE and CDE environments from the Style Manager program during a session.
StyleManager->Window->FocusFollowsMouse