Game Development Reference
Figure 7.2 Using point blending.
camera this technique definitely lacks the finesse that customers expect.
Therefore, our system wants the ability for vertices to be influenced by
more than one bone, without suffering a significant performance
Figure 7.2 illustrates how point blending can eliminate the unwanted
nipping when deforming a single mesh character. If you look closely you
will see that vertex B from the leg mesh is created from a combination of
the vertex location of vertex A from the thigh control and vertex C from the
calf control. This very focused control over vertex locations using controls,
where more than one control can affect a single vertex, is the aim of our
deformation system. Then it becomes the job of the artist to minimize the
number of vertices that are deformed by more than one control.
One possible solution to bone deformation systems
One way to achieve this level of control is to dynamically create a set of
vertices from a list of point indices that relate to your target mesh. An
example may help (see Figure 7.3).
Here we have a very simple mesh, with just 12 vertices. We want a
bone deformation system that allows Bone01 to deform vertices 1-8 and
Bone02 to deform vertices 5-12. In this system both bones deform
vertices 5-8, Bone01 alone deforms vertices 1-4 and Bone02 alone