Code:

 collisionConfiguration = new btDefaultCollisionConfiguration();         ///use the default collision dispatcher. For parallel processing you can use a diffent dispatcher (see Extras/BulletMultiThreaded)         dispatcher = new btCollisionDispatcher(collisionConfiguration);         ///btDbvtBroadphase is a good general purpose broadphase. You can also try out btAxis3Sweep.         overlappingPairCache = new btDbvtBroadphase();         ///the default constraint solver. For parallel processing you can use a different solver (see Extras/BulletMultiThreaded)         solver = new btSequentialImpulseConstraintSolver;         dynamicsWorld = new btDiscreteDynamicsWorld(dispatcher,overlappingPairCache,solver,collisionConfiguration);       dynamicsWorld->setGravity(Gravity);   debugDrawer = new DebugDrawer;         dynamicsWorld->setDebugDrawer(debugDrawer);     dynamicsWorld->getDebugDrawer()->setDebugMode(btIDebugDraw::DBG_DrawWireframe); //dynamicsWorld->setDebugDrawer(&debugDrawer);       dynamicsWorld->debugDrawWorld();