A typical 3D character
can be made up of many surfaces and components. To ensure that the
character animates in the way that you want, it is important to
carefully plan the process of character setup.
Character
setup or rigging is the general term used
for the preparation of 3D models with their accompanying joints
and skeletons for animation.
Depending on the model
to be animated, character setup can involve the following techniques:
- Creating a skeleton with joints that
acts as a framework for the 3D character model. You set limits on
the joints so they rotate in a convincing manner. When you animate
the character, you position the character’s joints using either
forward or inverse kinematic techniques (FK or IK).
- Binding the 3D surfaces to the skeleton
so that they move together. The process of binding may also include
defining how the character’s joints bend or how the skin surfaces
bulge to simulate muscles.
- Defining and setting constraints for
particular animated attributes in order to restrict the range of
motion or to control an attribute based on the movement of another.
- Grouping surface components such as CVs
into sets called clusters so that parts of the
character can be animated at a more detailed level.
This chapter introduces
you to the most common character setup features:
