Real time physics

Physically based simulation is a significant and active research field in computer graphics. It has emerged in the late eighties out of the need to make animations more physically plausible and to free the animator from explicitly specifying the motion of complex passively moving objects. In the early days, quite simple approaches were used to model physical behavior such as mass-spring networks or particle systems. Later, more and more sophisticated models borrowed from computational sciences were adopted. The computational sciences appeared decades before computer graphics with the goal of replacing real world experiments with simulations on computers. In contrast, the aim of using physical simulations in graphics was, and still is, the reproduction of the visual properties of physical processes for special effects in commercials and movies. Computer generated special effects have replaced earlier methods such as stop-motion frame-by-frame animation and offer almost unlimited possibilities.