4.4 The Update Pass 277
child calls to prevent them from propagating the world bounding volumes to the root
node.
The controller updates might or might not affect the transformation system. For
example, the point, particles, and morph controllers all modify the model-space ver-
tices (and possibly the model-space normals). Each of these call
UpdateMS to guaran-
tee the model bounding volume is current. Fortunately, this step occurs before our
UpdateGS gets to the stage of updating world bounding volumes. Keyframe and in-
verse kinematics controllers modify local transformations, but they do not set the
WorldIsCurrent flag to true because the world transformations must still be updated.
The skin controllers modify the world transformations directly and ...