needless setWorldTransform() calls (in btMotionState)

[dphil]

I have some code that updates various data when a rigid body's motion state's setWorldTransform() is called by the engine. Basically, when the body moves, I want to know about it and do something. But I found that setWorldTransform is being called at every simulation tick that the body is awake, regardless of whether it has moved or not. This isn't a big deal... I can simply do my own checks to see if the transform passed in is actually different than the previous one (and if so, trigger my response code), but I was just curious if there is some setting to silence calls from the physics engine when no actual change to the body's transform has occurred.