Final Character Deformation - Game Character Development with Maya - page 879

Note
It's important to realize that you will not get every joint to deform realist-
ically. We are limited to the geometry and the skeleton that we use to de-
form it, so all we can do is work toward the best possible result. With joint
and polygon restrictions, you won't get the character to deform perfectly
in all situations.
Wrist
We've arrived at the wrist. Like the shoulder, it needs all degrees of freedom weighted cor-
rectly, but here the weight painting is pretty straightforward.
Again we have to think about priority when working on the wrist. We can achieve a good
bend when the wrist rotates around the Y axis or Z axis, but this is at the sacrifice of the
X rotation, which makes the wrist twist. Think about what actions your character is most
likelytodomore—iftheyareholdingweapons,theYandZrotationswillmorelikelytake
priority; but if the character's actions cause the wrist to twist a lot, then the X rotation will
have to offer better deformation.
First, rotate the wrist around the Y and X axes to see how it deforms. You will no doubt
notice that the geometry moves with the action in a way that makes the wrist appear to
bend unnaturally. This is because the weights are evenly distributed between the forearm
and wrist joints. We now need to lock some of these weights down.
1. Select the mesh and open the Paint Skin Weights window. Set Opacity to 1 and
Value to 0 , and select L_Wrist in the Influence pane.
2. Paint the vertices just above the wrist, removing the wrist joint's influence ( Figure
14.13 , middle). Then make sure the vertices immediately below the wrist are fully
weighted to it ( Figure 14.13 , right).