Soft Body Dynamics - Learning Game Physics with Bullet Physics and OpenGL - page 129

Note
Note that we cannot pick up and move this object with the left-mouse button be-
cause it is not a rigid body, and our picking code exits only if it detects so (other-
wise it would crash!).
Soft bodies are very complex objects with a lot of mathematics behind them. Con-
sequently, they are processor intensive, and there are many values that can be
tweaked to generate the desired effect. This data can be accessed through the fol-
lowing two member variables of the soft body object: m_cfg and m_materials .
To see more interesting scenarios involving soft bodies, check out the
App_SoftBody demo in Bullet's demo applications.