Get/Set the custom Object that implements the PhysicsCallbacks.ITransformWriteCallback to which PhysicsEvents.TransformWriteEvent and PhysicsEvents.TransformTweenWriteEvent will be sent. The callback will only occur if _transformWriteMode is set to PhysicsWorld.TransformWriteMode.Custom and there are _bodyUpdateEvents available. The object assigned here will be kept alive, not allowing the GC to dispose of it. To remove the object assigned here, set the callback target to NULL.

public object transformWriteCallbackTarget { get; set; }