User`s guide

5 Build Virtual Reality Worlds
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You can achieve best results by using the proportional method of tessellation (arcs
are substituted by line segments based on their relative, not absolute, accuracy). This
method works for models regardless their dimensions. For maximum accuracy of the
exported VRML model, set the slider at the rightmost position. If the resulting file is
too complex to be handled effectively with VRML rendering tools, experiment with this
accuracy setting. You want to find the setting that gives you the smallest possible VRML
model, but it must still be visually acceptable.
VRML Export Filter Settings
The CATIA software enables you to tune some VRML export options. These are available
in the Tools > Options > General > Compatibility > VRML:
• Select VRML97 as the export format
The Simulink 3D Animation software uses VRML97 standard format.
• Select the Save normals check box
This option affects whether or not to export explicit face normals definitions.
• Clear the Save edges check box
Clear this check box for optimum performance. Selecting this check box directs the
CATIA software to also export object edges (in the form of IndexedLineSets).
• Select the appropriate Save textures check boxes to the desired settings
In particular, if you want to save textures, select the Save textures in external
files option. This option generates external JPG files for object textures.
• Select the VRML model background color
This option applies only to exporting products.
Structure of VRML Models Exported from the CATIA Environment
The CATIA software exports CATProducts and their CATParts as VRML transforms.
The structure of these transforms corresponds to the CATIA model hierarchy. In addition
to transforms that represent physical elements, the CATIA software creates several
transforms and groups in the VRML file to represent relationships between objects and
other model properties defined in the CATIA environment.
Some of these additional nodes can be empty. Many CATIA model properties do not have
equivalents in the VRML language. Each part transform contains a hierarchy of nested
transforms, groups and shapes that correspond to the part internal structure. Some of