Game Development Reference
In-Depth Information
The Process
The process of getting a lifelike character into a game goes like this:
1.
Clean up completed textured models.
2.
Create a
rig
. A rig is a collection of
joints
that can deform the polygons of
a model. This rig can vary greatly in its complexity and flexibility and will
depend on how much animation is actually needed for a given character.
3.
Skin
the rig to the model. Skinning is the process of attaching the rig of
joints to the polygons they will affect. Maya 2011 has some new skinning
tools that help make this process faster.
4.
Animate the rig. Animating the rig means rotating (mostly) and moving
the joints and setting keyframes to record that motion over time. As the
joints rotate or move, the polygons attached to them will move and viola!
the character looks alive.
5.
Bake the animation. Baking an animation is the process of simplifying
animation of joints down to the simplest translation or rotation keyframes.
This means that more-complex (but powerful) tools like IK (inverse
kinematics) are baked out of the animated output; thus the baked
version isn't particularly editable, but the results in Unity are much more
predictable.
6.
Export the baked animated character (as an .fbx).
7.
Import the .fbx into Unity.
8.
Divide the animations.
9.
Call them up either via Play Automatically or via script.
I know. That looks like a lot at first blush; but it's actually very manageable in
these sorts of short discreet steps. In this chapter we will be going through
a simplified version of this entire process. The rig will be fairly simple but will
allow us to create some animation quickly.
Since the game is a first-person shooter, we won't see the character very
much. This would be very different for a third-person situation. However,
knowing how to work with characters is an important part of Unity's game-
creation capabilities, so we will make a small mini-level that shows what “you”
(Aegis Chung) look like before he, er . . . you, undertake your mission.
Tutorial 10.1: Rigging
Cleanup
In the process of creating and texturing the character, there undoubtedly was
quite a bit of Maya construction history that was built up. Each projection and
every tweak generated a new node, which can be very helpful to be able to
access while working, but at the end of the process represent a huge amount
of extra data that we no longer need. Of further concern with these nodes is
that the .fbx export doesn't always do well with the nodes and some strange
output files can be the result.
