added btInternalTickCallback, see btDynamicsWorld::setInternalTickCallback

Thanks chunky!

http://www.bulletphysics.com/Bullet/phpBB3/viewtopic.php?f=9&t=1991

src/BulletDynamics/Dynamics/btContinuousDynamicsWorld.cpp

@@ -77,7 +77,6 @@ void	btContinuousDynamicsWorld::internalSingleStepSimulation( btScalar timeStep)
 	solveConstraints(getSolverInfo());
 	
 	///CallbackTriggers();
-
 	calculateTimeOfImpacts(timeStep);
 
 	btScalar toi = dispatchInfo.m_timeOfImpact;
@@ -96,6 +95,9 @@ void	btContinuousDynamicsWorld::internalSingleStepSimulation( btScalar timeStep)
 
 	updateActivationState( timeStep );
 	
+	if(0 != m_internalTickCallback) {
+		(*m_internalTickCallback)(this, timeStep);
+	}
 }
 
 void	btContinuousDynamicsWorld::calculateTimeOfImpacts(btScalar timeStep)
@@ -188,3 +190,4 @@ void	btContinuousDynamicsWorld::updateTemporalAabbs(btScalar timeStep)
 }
 
 
+

src/BulletDynamics/Dynamics/btDiscreteDynamicsWorld.cpp

@@ -375,6 +375,9 @@ void	btDiscreteDynamicsWorld::internalSingleStepSimulation(btScalar timeStep)
 
 	updateActivationState( timeStep );
 
+	if(0 != m_internalTickCallback) {
+		(*m_internalTickCallback)(this, timeStep);
+	}	
 }
 
 void	btDiscreteDynamicsWorld::setGravity(const btVector3& gravity)

src/BulletDynamics/Dynamics/btDynamicsWorld.h

@@ -21,6 +21,9 @@ class btTypedConstraint;
 class btRaycastVehicle;
 class btConstraintSolver;
 
+class btDynamicsWorld;
+/// Type for the callback for each tick
+typedef void (*btInternalTickCallback)(const btDynamicsWorld *world, btScalar timeStep);
 
 enum btDynamicsWorldType
 {
@@ -36,7 +39,7 @@ class btDynamicsWorld : public btCollisionWorld
 		
 
 		btDynamicsWorld(btDispatcher* dispatcher,btBroadphaseInterface* broadphase,btCollisionConfiguration* collisionConfiguration)
-		:btCollisionWorld(dispatcher,broadphase,collisionConfiguration)
+		:btCollisionWorld(dispatcher,broadphase,collisionConfiguration), m_internalTickCallback(0)
 		{
 		}
 
@@ -81,8 +84,14 @@ class btDynamicsWorld : public btCollisionWorld
 
 		virtual void	clearForces() = 0;
 
+		/// Set the callback for when an internal tick (simulation substep) happens
+		void setInternalTickCallback(btInternalTickCallback cb) { m_internalTickCallback = cb; }
+		
+		btInternalTickCallback m_internalTickCallback;
+
 
 };
 
 #endif //BT_DYNAMICS_WORLD_H
 
+