This sub-topic gives you general information when performing a symmetry.
The symmetry keeps the curvature continuity of the subdivision
surface, therefore some details of the input mesh will be modified.
As the result of the symmetry is a subdivision surface, you can
perform a symmetry of a symmetry or copy-paste a symmetry or use
this feature to associate other subdivision surfaces.
If the face of the subdivision surface has only one vertex on the chosen side,
the result of the symmetry is a mirror surface.
The display of the
projection plane depends on the option selected for transparency in
Tools > Options > Display > Performance tab,
Transparency Quality area, that is either Low (Screen
Door) or High (Alpha Blending).
For more information on these options, refer to
CATIA
Infrastructure User's Guide: Customizing: Customizing settings:
Performance.
Shapes
This sub-topic explains how a symmetry is performed depending on the shape of the subdivision surface.
If the surface is U-shaped, you cannot select a side as it is
automatically chosen:
If the symmetry plane intersects a S-shaped surface, the symmetry
cannot be performed.
Below is an example using the green plane, the symmetry cannot be
performed:
Below is an example using the red plane: the symmetry can be
performed.