First and second resilient deformable spheres each have a pattern such as dots or a grid of lines projected or printed/deposited onto their inner surfaces, a camera positioned to image the pattern. When the spheres are deformed, the patterns are distorted. Distortions in the patterns are mapped to input signals to a computer simulation or other computer program. The spheres may each be attached to respective ends of a hollow tube also bearing the pattern such that not only can the spheres be squeezed, but the assembly also can be twisted to deform the pattern in the tube for further correlation to input signals.