Game Development Reference
In-Depth Information
KINEMATICS
Kinematics, for those of you without a background in character animation, is the means of posing the character at key
positions to create the animation. With inverse kinematics, a child object in the hierarchy controls the position and
rotation of the parent objects in the hierarchy. In FK (forward kinematics), the parents control the children's location and
orientation. An example would be an arm hierarchy. To position the your hand at a particular place using FK, you would
individually rotate your upper arm, lower arm and wrist into position. With an IK linkage, if you use your other hand to
position your wrist, your forearm and upper arm will automatically be adjusted into place according to the the rotational
constraints on their joints.
Generic Rigs
While the full power of Mecanim is realized only with humanoid characters, you will still be able to
benefit from many of Mecanim's features by using Generic rigs. To use the Humanoid Animation
Type, a character must have at least 11 bones and be roughly humanoid. Anything else will have to
use the Generic Animation Type option. This is useful for minimal characters, animals, and anything
else that has at least an idle animation.
For your introduction to Mecanim, you will set up a ZombieBunny from the Animation Imports folder.
These brainless eating machines have one goal: to eat all the plants in your garden! They have a
very simple animation: they chew and they move forward as they chew. The ZombieBunny asset
is a good size for a real bunny, but a zombie bunny should be larger and more of a threat (and an
easier target). If you can't bring yourself to destroy even zombie bunnies, feel free to substitute the
AlienHerbavore for the ZombieBunny for the topic's project.
1.
Select the ZombieBunny from the Character Imports folder.
2.
In the Model section, increase its Scale Factor to
.015
.
3.
In the Rig section, set the Root Node to Bunny Motion Root (Figure
6-8
).
