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1. Utility Programs

There are three programs that you need to learn about in order to use Open Inventor to create your own 3D scenes and animations. It is assumed that you are already familiar with using some editor program like emacs for editing simple text files.

1.1 ivview

The ivview program is something you use to view the Open Inventor files that you will create. It is easy enough to use. Give it a try by typing the command (from the Athena prompt):

    ivview /usr/share/data/models/chair.iv &

Use the mouse to move the chair around so that you can see it from different angles. Play around with the various controls on ivview to see what they do.

1.2 ivquicken

You won't often need to use ivquicken, but you should understand what it is. It is a utility for taking a complex scene description and performing transformations that optimize the scene graph so that programs like ivview can render the scene more efficiently. You can also use ivquicken for converting particular scene description files between ASCII and binary formats.

Important Note

By default, ivview will always run ivquicken on a file before it displays it. If you are writing animations, you may run into a bug where ivquicken makes incorrect transformations to the file. Whenever you are working on animations you should use ivview with the -q option so that it won't use ivquicken. For example:

    ivview -q /usr/share/data/models/chair.iv &

You may want to get into the habit of only using ivview in this way, at least until your scene files get complex enough for you to even care about optimizing them.

1.3 showcase

The showcase program is a reasonably full-featured graphical editor for letting you build complex objects interactively. It takes a bit of fiddling and experimenting to learn how to use it. The best way to start is to go into the Gizmo menu and use it to open up the 3D Gizmo. A window will appear entitled "Showcase 3D Gizmo". Click on Create, and wait 20 or 30 seconds while it creates a 3-dimensional grid for you to work in. When a flickering outline appears, click to position it on the work surface that showcase provides. Experiment and have fun. Don't be surprised if it seems a bit difficult and unintuitive to use at first. If you are trying to create very simple objects, you'll be better of writing an Open Inventor file by hand. Using showcase is a more worthwhile effort when creating complex objects.

If you have a result you want to keep, you can save it to a file. By default, showcase has its own particular format for storing an object to a file, but you can use the File menu's Save As... option to convert the output into an Open Inventor binary file. Just choose the "...As 3D (Inventor)" option from there, and you'll be all set.

More Information

For more information about any of these utilities consult the man pages for them by typing any of the following commands at the Athena prompt:

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