added synchronizeSingleMotionState, thanks Chunky.

src/BulletDynamics/Dynamics/btDiscreteDynamicsWorld.cpp

@@ -250,18 +250,11 @@ void	btDiscreteDynamicsWorld::applyGravity()
 }
 
 
+void	btDiscreteDynamicsWorld::synchronizeSingleMotionState(btRigidBody* body)
+{
+	btAssert(body);
 
-void	btDiscreteDynamicsWorld::synchronizeMotionStates()
-{
-	BT_PROFILE("synchronizeMotionStates");
-	{
-		//todo: iterate over awake simulation islands!
-		for ( int i=0;i<m_activeObjects.size();i++)
-		{
-			btCollisionObject* colObj = m_activeObjects[i];
-			
-			btRigidBody* body = btRigidBody::upcast(colObj);
-			if (body && body->getMotionState() && !body->isStaticOrKinematicObject())
+	if (body->getMotionState() && !body->isStaticOrKinematicObject())
 	{
 		//we need to call the update at least once, even for sleeping objects
 		//otherwise the 'graphics' transform never updates properly
@@ -275,6 +268,21 @@ void	btDiscreteDynamicsWorld::synchronizeMotionStates()
 		}
 	}
 }
+
+
+void	btDiscreteDynamicsWorld::synchronizeMotionStates()
+{
+	BT_PROFILE("synchronizeMotionStates");
+	{
+		//todo: iterate over awake simulation islands!
+		for ( int i=0;i<m_activeObjects.size();i++)
+		{
+			btCollisionObject* colObj = m_activeObjects[i];
+			
+			btRigidBody* body = btRigidBody::upcast(colObj);
+			if (body)
+				synchronizeSingleMotionState(body);
+		}
 	}
 
 	if (getDebugDrawer() && getDebugDrawer()->getDebugMode() & btIDebugDraw::DBG_DrawWireframe)

src/BulletDynamics/Dynamics/btDiscreteDynamicsWorld.h

@@ -92,6 +92,9 @@ public:
 
 	virtual void	synchronizeMotionStates();
 
+	///this can be useful to synchronize a single rigid body -> graphics object
+	void	synchronizeSingleMotionState(btRigidBody* body);
+
 	void	addConstraint(btTypedConstraint* constraint, bool disableCollisionsBetweenLinkedBodies=false);
 
 	void	removeConstraint(btTypedConstraint* constraint);