Combining active and passive simulations for secondary motion

Describes how to generate secondary motion by coupling physically based simulations of passive objects to actively controlled characters. Our approach of using coupled simulations is general, can be applied to a wide range of phenomena and can add visual richness to an animated scene. While we simulated the secondary motion of many of the objects in the scene, a number of objects remain motionless. In some cases, modeling a few of the moving and flexible objects appears to emphasize the lack of motion in the others. Like the progression in models from wireframe to polygonal to subdivision surfaces, this increase in fidelity may also increase the viewer´s expectations