A joint's map includes weight for every VERTEX.

When you select a joint's map, you can display the area affected by it. These are shades of gray to white. Every other area of the mesh is black. The black areas are not affected by the selected joint's rotations, but now that you've confronted me on this, I suppose they are mapped, to 0. * *

I don't know how efficent this is for programmers.

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