Understanding the Linear Blend Skinning technique

Once we have a good representation of the 3D human body, we want to model how it looks in different poses. This is particularly important for character animation. The idea is that skinning involves enveloping an underlying skeleton with a skin (a surface) that conveys the appearance of the object being animated. This is a term used in the animation industry. Typically, this representation takes the form of vertices, which are then used to define connected polygons to form the surface.

The Linear Blend Skinning model is used to take a skin in the resting pose and transform it into a skin in any arbitrary pose using a simple linear model. This is so efficient to render that many game engines support this technique, and it is also used to render game characters in real time.

Figure 8.2 – Initial blend shape (left) and deformed mesh generated with blend skinning (right)

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