Enable continuous collision detection.

PHY SET CONTINUOUS CD value#

value

Float
controls whether continous collision detection is enabled or disabled

Continuous collision detection is useful for fast moving objects. With traditional collision detection fast moving objects can pass through other objectsduring a single time step. This effect is known as tunneling. Imagine a bullet traveling towards a thin metal plate, in the first time step it would be on one side and in the next it would be on the other. The physics engine would never detect a collision and hence not constrain the motion of the bullet.

To deal with this problem a technique known as continuous collision detection ( CCD ) is necessary, instead of testing for collisionat discrete points it tests an extruded volume which represents the objects motion during the whole time step. If a collision is detected, the time of impact can be computed and the objects motion constrained appropriately. Currently CCD is only supported between dynamic mesh objects and the static environment.

Because CCD is slow in comparison to discrete collision detection methods, there are a couple of optimizations. Firstly CCD is only applied to fast moving objects, if an object is simply resting on a surface, then discrete collision detection is sufficient. Secondly CCD is performed with a skeleton ( mesh ) embedded within the object, this can be simpler than the geometry used for discrete collision detection. Hence the skeleton stops the object flying through other objects and a higher frequency discrete collision object can provide morerealistic behavior when the object is resting or rolling on another. A CCD Skeleton is a kind of mesh. It has a special name because its stored in a special format, and there are less restrictions on it than on other kinds of meshes. In addition a single CCD skeleton can be associated with multiple shapes to reduce the memory overhead. Use a value of 1.0 to enable CCD and a value of 0.0 to disable CCD.

No example code is provided for this command