Dynamic skinning: adding real-time dynamic effects to an existing character animation

ABSTRACT

This paper proposes a simple and efficient technique to enhance classical animations of characters by adding a dynamic response of the skin to the movement of the underlying skeleton. The dynamic effects are locally added to the shape obtained through the standard skinning by specifying flesh elements. Our solution relies on a new second skinning operation that blends the current flesh volume computed through smooth skinning with its position in a dynamic frame attached to the skeleton through a visco-elastic element which, combined with a set of weights, controls the local behavior of tissues. We show how the weights can be automatically computed, taking into account the morphology of the limb. The resulting real-time technique is well suited to video games or any application where we need to add dynamic effects, at almost no cost, to an existing animation sequence.

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INDEX TERMS

Primary Classification:
  I. Computing Methodologies
  I.3 COMPUTER GRAPHICS
      I.3.7 Three-Dimensional Graphics and Realism
          Subjects: Animation

Keywords:
dynamics, real-time, skinning