Simulating Cartoon Style Animation

This paper concentrates on producing cartoon style deformations automatically. Basing their method on squash and stretch. Where the stretch anticipates the collision and the squash exaggerates its effects.

Underlying their system is a simulator that generates ballistic motion for the centre of mass of each object and includes a collision detection mechanism for affinely deformed bodies.

Brings up some interesting stylistic decisions e.g. Deform the object in the direction of travel.

At this stage squash and stretch is achieved by keyframing, but there are 3 approaches proposed for simulating squash and stretch:
- Physically based models,
- Implicit surface deformations,
- Time warp methods.

Notes: -Their system uses only non-uniform, affine scaling deformations.
-Collision detection is achieved using a modified version of Vclip

Overall, this system is for real-time simulation of squash and stretch, but they do comment at the end that the broader question of global motion (e.g. Anticipation & follow through), which require changes to trajections and timing, are the most important areas for future work.

Origins Marey Muybridge Fleischer Rob Bredow Q & A Debate Siggraph Panel CG Animation Pipeline Future Squash and Stretch Splines Experiment Summary Further Reading

(c) Shane Aherne 2005