User`s guide

5 Build Virtual Reality Worlds
5-50
• CylinderSleeve1
• PistonAssembly1
• CrankshaftAssembly1
The export does not preserve the CATProduct and CATPart names. You can identify
these objects in the VRML file in the tree view and in the text mode. In the figure, the
contents of the part transforms are collapsed so that only the top-level objects are visible
for clarity. After four transforms representing CATParts, the export adds an empty
Group node at the place where CATIA Constraints are defined. You can delete such
empty nodes from the VRML model.
The contents of the CATProduct are scaled down by a factor of 1000 (conversion of units
from millimeters to meters).
When you have VRML files created with the CATIA software, take into account the
following known features for further use with the Simulink 3D Animation software:
• Object - Exporting to VRML does not preserve CATProduct and CATPart names.
The CATIA environment only creates synthetic VRML DEF names for sub-parts,
materials, and object coordinate fields. These synthetic names change between two or
more consecutive export operations.
To work with the Simulink 3D Animation software, provide meaningful DEF names
for the objects that you want to control from the MATLAB /Simulink environment.
• The CATIA software saves all vertex coordinates for a part in one VRML coordinate
field, which resides in the first exported IndexedFaceSet for the part. This field is
referenced from several sub-parts throughout the file with the USE directive.
Preserve this reference. Do not delete or rename the original Coordinate field DEF
name.
• The VRML file stores only one material per part. If the part consists of several sub-
parts in VRML, their material also uses the USE reference to the material of the first
sub-part.
• Textures are supported
• LOD (exporting parts in several levels of detail for more efficient visualization) is not
supported
• The CATIA software exports models in millimeters, VRML units are meters.
Scale resulting objects to visualize them effectively.
• The VRML file does not save user-defined CATIA viewpoints.