Physics-based characters can produce realistic reaction to external forces such as gravity, or collision contact. SmartBody now supports physics simulation to drive the character animations.
A physics character is basically a set of connected body links based on his skeleton topology. During setup, user needs to provide appropriate mass, collision geometries, and joint parameters for the character. At run-time, physical simulation will update the new body link position and orientation at each time step to achieve realistic motions. A basic example is the ragdoll, which simulate the character with only gravity and collisions. In addition to ragdolls, SmartBody also supports more advanced feature like pose tracking. It enables the character to follow an input kinematic motions under physical simulation.
In our current implementation, Open Dynamic Engine (ODE) is used as our simulation engine. In the future, we would like to support multiple physics engines such as PhysX or Bullets.