Practical Algorithms for 3D Computer Graphics, 2nd Edition

212 6. Computer animation

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v

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v

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v´

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Figure 6.17: A simple s keleton in two poses with local frames of reference given by

vectors u, v and w. All the w vecto r s are at right angles to both u and v and therefore

they point into the page and thus are not visible in the diagram.

section to develop a strategy for hierarchical interpolation which minimizes the

complexity.

The main difficulty with a moving frame of referen ce can be illustrated by

looking back to the example in figure 6.14, which is rep r oduced in figure 6.17

with additional vectors depicting the local frames of reference at the nodes on

the end of the bones.

Consider