Not only can you animate transform groups, cameras, lights and materials, you can also animate the geometry of a shape itself, causing it to deform. Again, you simply use interpolators, routing new values to a shape's geometry fields. Many 3D modelling packages enable you to create advanced geometry deformations, and (in the case of Lightwave, Inspire 3D, and 3D Studio Max) also export the animation to VRML. You can also hand-animate simple deformation (e.g. a ball hitting the ground) using a simple interpolator to modify a transform group's scale value.