Пример #1
0
void MultiBodyVehicleSetup::initPhysics(GraphicsPhysicsBridge& gfxBridge)
{
    int upAxis = 1;

    btVector4 colors[4] =
    {
        btVector4(1,0,0,1),
        btVector4(0,1,0,1),
        btVector4(0,1,1,1),
        btVector4(1,1,0,1),
    };
    int curColor = 0;



    gfxBridge.setUpAxis(upAxis);

	this->createEmptyDynamicsWorld();
    gfxBridge.createPhysicsDebugDrawer(m_dynamicsWorld);
    m_dynamicsWorld->getDebugDrawer()->setDebugMode(
        //btIDebugDraw::DBG_DrawConstraints
        +btIDebugDraw::DBG_DrawWireframe
        +btIDebugDraw::DBG_DrawContactPoints
        +btIDebugDraw::DBG_DrawAabb
        );//+btIDebugDraw::DBG_DrawConstraintLimits);

    
    createMultiBodyVehicle();
    
    if (1)
    {
        btVector3 groundHalfExtents(20,20,20);
        groundHalfExtents[upAxis]=1.f;
        btBoxShape* box = new btBoxShape(groundHalfExtents);
        box->initializePolyhedralFeatures();
        
        gfxBridge.createCollisionShapeGraphicsObject(box);
        btTransform start; start.setIdentity();
        btVector3 groundOrigin(0,0,0);
        groundOrigin[upAxis]=-1.5;
        start.setOrigin(groundOrigin);
        btRigidBody* body =  createRigidBody(0,start,box);
        btVector4 color = colors[curColor];
        curColor++;
        curColor&=3;
        gfxBridge.createRigidBodyGraphicsObject(body,color);
    }

}
Пример #2
0
void ImportUrdfSetup::initPhysics()
{

	
	m_guiHelper->setUpAxis(m_upAxis);
	
	this->createEmptyDynamicsWorld();
	//m_dynamicsWorld->getSolverInfo().m_numIterations = 100;
    m_guiHelper->createPhysicsDebugDrawer(m_dynamicsWorld);
    m_dynamicsWorld->getDebugDrawer()->setDebugMode(
    btIDebugDraw::DBG_DrawConstraints
    +btIDebugDraw::DBG_DrawContactPoints
    +btIDebugDraw::DBG_DrawAabb
        );//+btIDebugDraw::DBG_DrawConstraintLimits);


	if (m_guiHelper->getParameterInterface())
	{
		SliderParams slider("Gravity", &m_grav);
		slider.m_minVal = -10;
		slider.m_maxVal = 10;
		m_guiHelper->getParameterInterface()->registerSliderFloatParameter(slider);
	}
	

	BulletURDFImporter u2b(m_guiHelper, 0);
	
	
	bool loadOk = u2b.loadURDF(m_fileName);

#ifdef TEST_MULTIBODY_SERIALIZATION	
	//test to serialize a multibody to disk or shared memory, with base, link and joint names
	btSerializer* s = new btDefaultSerializer;
#endif //TEST_MULTIBODY_SERIALIZATION

	if (loadOk)
	{
		//printTree(u2b,u2b.getRootLinkIndex());

		//u2b.printTree();

		btTransform identityTrans;
		identityTrans.setIdentity();


		{




			//todo: move these internal API called inside the 'ConvertURDF2Bullet' call, hidden from the user
			//int rootLinkIndex = u2b.getRootLinkIndex();
			//b3Printf("urdf root link index = %d\n",rootLinkIndex);
			MyMultiBodyCreator creation(m_guiHelper);

			ConvertURDF2Bullet(u2b,creation, identityTrans,m_dynamicsWorld,m_useMultiBody,u2b.getPathPrefix());
			m_data->m_rb = creation.getRigidBody();
			m_data->m_mb = creation.getBulletMultiBody();
			btMultiBody* mb = m_data->m_mb;
			for (int i = 0; i < u2b.getNumAllocatedCollisionShapes(); i++)
			{
				m_collisionShapes.push_back(u2b.getAllocatedCollisionShape(i));
			}

			if (m_useMultiBody && mb )
			{
				std::string*   name = new std::string(u2b.getLinkName(u2b.getRootLinkIndex()));
				m_nameMemory.push_back(name);
#ifdef TEST_MULTIBODY_SERIALIZATION
				s->registerNameForPointer(name->c_str(),name->c_str());
#endif//TEST_MULTIBODY_SERIALIZATION
				mb->setBaseName(name->c_str());
				//create motors for each btMultiBody joint
				int numLinks = mb->getNumLinks();
				for (int i=0;i<numLinks;i++)
				{
					int mbLinkIndex = i;
					int urdfLinkIndex = creation.m_mb2urdfLink[mbLinkIndex];

					std::string* jointName = new std::string(u2b.getJointName(urdfLinkIndex));
					std::string* linkName = new std::string(u2b.getLinkName(urdfLinkIndex).c_str());
#ifdef TEST_MULTIBODY_SERIALIZATION					
					s->registerNameForPointer(jointName->c_str(),jointName->c_str());
					s->registerNameForPointer(linkName->c_str(),linkName->c_str());
#endif//TEST_MULTIBODY_SERIALIZATION
					m_nameMemory.push_back(jointName);
					m_nameMemory.push_back(linkName);

					mb->getLink(i).m_linkName = linkName->c_str();
					mb->getLink(i).m_jointName = jointName->c_str();
							
					if (mb->getLink(mbLinkIndex).m_jointType==btMultibodyLink::eRevolute
					    ||mb->getLink(mbLinkIndex).m_jointType==btMultibodyLink::ePrismatic
					)
					{
						if (m_data->m_numMotors<MAX_NUM_MOTORS)
						{
							
							char motorName[1024];
							sprintf(motorName,"%s q'", jointName->c_str());
							btScalar* motorVel = &m_data->m_motorTargetVelocities[m_data->m_numMotors];
							*motorVel = 0.f;
							SliderParams slider(motorName,motorVel);
							slider.m_minVal=-4;
							slider.m_maxVal=4;
							m_guiHelper->getParameterInterface()->registerSliderFloatParameter(slider);
							float maxMotorImpulse = 10.1f;
							btMultiBodyJointMotor* motor = new btMultiBodyJointMotor(mb,mbLinkIndex,0,0,maxMotorImpulse);
							//motor->setMaxAppliedImpulse(0);
							m_data->m_jointMotors[m_data->m_numMotors]=motor;
							m_dynamicsWorld->addMultiBodyConstraint(motor);
							m_data->m_numMotors++;
						}
					}

				}
			} else
			{
				if (1)
				{
					//create motors for each generic joint
					int num6Dof = creation.getNum6DofConstraints();
					for (int i=0;i<num6Dof;i++)
					{
						btGeneric6DofSpring2Constraint* c = creation.get6DofConstraint(i);
						if (c->getUserConstraintPtr())
						{
							GenericConstraintUserInfo* jointInfo = (GenericConstraintUserInfo*)c->getUserConstraintPtr();
							if ((jointInfo->m_urdfJointType ==URDFRevoluteJoint) || 
								(jointInfo->m_urdfJointType ==URDFPrismaticJoint) ||
								(jointInfo->m_urdfJointType ==URDFContinuousJoint))
							{
								int urdfLinkIndex = jointInfo->m_urdfIndex;
								std::string jointName = u2b.getJointName(urdfLinkIndex);
								char motorName[1024];
								sprintf(motorName,"%s q'", jointName.c_str());
								btScalar* motorVel = &m_data->m_motorTargetVelocities[m_data->m_numMotors];

								*motorVel = 0.f;
								SliderParams slider(motorName,motorVel);
								slider.m_minVal=-4;
								slider.m_maxVal=4;
								m_guiHelper->getParameterInterface()->registerSliderFloatParameter(slider);
								m_data->m_generic6DofJointMotors[m_data->m_numMotors]=c;
								bool motorOn = true;
								c->enableMotor(jointInfo->m_jointAxisIndex,motorOn);
								c->setMaxMotorForce(jointInfo->m_jointAxisIndex,10000);
								c->setTargetVelocity(jointInfo->m_jointAxisIndex,0);
								
								m_data->m_numMotors++;
							}
						}
					}
				}
				
			}
		}

		//the btMultiBody support is work-in-progress :-)

        for (int i=0;i<m_dynamicsWorld->getNumMultiBodyConstraints();i++)
        {
            m_dynamicsWorld->getMultiBodyConstraint(i)->finalizeMultiDof();
        }



		bool createGround=true;
		if (createGround)
		{
			btVector3 groundHalfExtents(20,20,20);
			groundHalfExtents[m_upAxis]=1.f;
			btBoxShape* box = new btBoxShape(groundHalfExtents);
			m_collisionShapes.push_back(box);
			box->initializePolyhedralFeatures();

			m_guiHelper->createCollisionShapeGraphicsObject(box);
			btTransform start; start.setIdentity();
			btVector3 groundOrigin(0,0,0);
			groundOrigin[m_upAxis]=-2.5;
			start.setOrigin(groundOrigin);
			btRigidBody* body =  createRigidBody(0,start,box);
			//m_dynamicsWorld->removeRigidBody(body);
		   // m_dynamicsWorld->addRigidBody(body,2,1);
			btVector3 color(0.5,0.5,0.5);
			m_guiHelper->createRigidBodyGraphicsObject(body,color);
		}

		
	}


#ifdef TEST_MULTIBODY_SERIALIZATION
	m_dynamicsWorld->serialize(s);
	b3ResourcePath p;
	char resourcePath[1024];
	if (p.findResourcePath("r2d2_multibody.bullet",resourcePath,1024))
	{
		FILE* f = fopen(resourcePath,"wb");
		fwrite(s->getBufferPointer(),s->getCurrentBufferSize(),1,f);
		fclose(f);
	}
#endif//TEST_MULTIBODY_SERIALIZATION

}
Пример #3
0
void TestJointTorqueSetup::initPhysics()
{
    int upAxis = 1;
	gJointFeedbackInWorldSpace = true;
	gJointFeedbackInJointFrame = true;

	m_guiHelper->setUpAxis(upAxis);

    btVector4 colors[4] =
    {
        btVector4(1,0,0,1),
        btVector4(0,1,0,1),
        btVector4(0,1,1,1),
        btVector4(1,1,0,1),
    };
    int curColor = 0;



    

	this->createEmptyDynamicsWorld();
    m_guiHelper->createPhysicsDebugDrawer(m_dynamicsWorld);
    m_dynamicsWorld->getDebugDrawer()->setDebugMode(
        //btIDebugDraw::DBG_DrawConstraints
        +btIDebugDraw::DBG_DrawWireframe
        +btIDebugDraw::DBG_DrawContactPoints
        +btIDebugDraw::DBG_DrawAabb
        );//+btIDebugDraw::DBG_DrawConstraintLimits);

	

    //create a static ground object
    if (1)
        {
            btVector3 groundHalfExtents(1,1,0.2);
            groundHalfExtents[upAxis]=1.f;
            btBoxShape* box = new btBoxShape(groundHalfExtents);
            box->initializePolyhedralFeatures();

            m_guiHelper->createCollisionShapeGraphicsObject(box);
            btTransform start; start.setIdentity();
            btVector3 groundOrigin(-0.4f, 3.f, 0.f);
            groundOrigin[upAxis] -=.5;
			groundOrigin[2]-=0.6;
            start.setOrigin(groundOrigin);
			btQuaternion groundOrn(btVector3(0,1,0),0.25*SIMD_PI);
		
		//	start.setRotation(groundOrn);
            btRigidBody* body =  createRigidBody(0,start,box);
			body->setFriction(0);
            btVector4 color = colors[curColor];
			curColor++;
			curColor&=3;
            m_guiHelper->createRigidBodyGraphicsObject(body,color);
        }

    {
        bool floating = false;
        bool damping = false;
        bool gyro = false;
        int numLinks = 2;
        bool spherical = false;					//set it ot false -to use 1DoF hinges instead of 3DoF sphericals
        bool canSleep = false;
        bool selfCollide = false;
          btVector3 linkHalfExtents(0.05, 0.37, 0.1);
        btVector3 baseHalfExtents(0.05, 0.37, 0.1);

        btVector3 basePosition = btVector3(-0.4f, 3.f, 0.f);
        //mbC->forceMultiDof();							//if !spherical, you can comment this line to check the 1DoF algorithm
        //init the base
        btVector3 baseInertiaDiag(0.f, 0.f, 0.f);
        float baseMass = 1.f;

        if(baseMass)
        {
            //btCollisionShape *shape = new btSphereShape(baseHalfExtents[0]);// btBoxShape(btVector3(baseHalfExtents[0], baseHalfExtents[1], baseHalfExtents[2]));
			btCollisionShape *shape = new btBoxShape(btVector3(baseHalfExtents[0], baseHalfExtents[1], baseHalfExtents[2]));
            shape->calculateLocalInertia(baseMass, baseInertiaDiag);
            delete shape;
        }

        bool isMultiDof = true;
        btMultiBody *pMultiBody = new btMultiBody(numLinks, baseMass, baseInertiaDiag, !floating, canSleep, isMultiDof);
		
        m_multiBody = pMultiBody;
        btQuaternion baseOriQuat(0.f, 0.f, 0.f, 1.f);
	//	baseOriQuat.setEulerZYX(-.25*SIMD_PI,0,-1.75*SIMD_PI);
        pMultiBody->setBasePos(basePosition);
        pMultiBody->setWorldToBaseRot(baseOriQuat);
        btVector3 vel(0, 0, 0);
    //	pMultiBody->setBaseVel(vel);

        //init the links
        btVector3 hingeJointAxis(1, 0, 0);
        
        //y-axis assumed up
        btVector3 parentComToCurrentCom(0, -linkHalfExtents[1] * 2.f, 0);						//par body's COM to cur body's COM offset
        btVector3 currentPivotToCurrentCom(0, -linkHalfExtents[1], 0);							//cur body's COM to cur body's PIV offset
        btVector3 parentComToCurrentPivot = parentComToCurrentCom - currentPivotToCurrentCom;	//par body's COM to cur body's PIV offset

        //////
        btScalar q0 = 0.f * SIMD_PI/ 180.f;
        btQuaternion quat0(btVector3(0, 1, 0).normalized(), q0);
        quat0.normalize();
        /////

        for(int i = 0; i < numLinks; ++i)
        {
			float linkMass = 1.f;
			//if (i==3 || i==2)
			//	linkMass= 1000;
			btVector3 linkInertiaDiag(0.f, 0.f, 0.f);

			btCollisionShape* shape = 0;
			if (i==0)
			{
				shape = new btBoxShape(btVector3(linkHalfExtents[0], linkHalfExtents[1], linkHalfExtents[2]));//
			} else
			{
				shape = new btSphereShape(radius);
			}
			shape->calculateLocalInertia(linkMass, linkInertiaDiag);
			delete shape;


            if(!spherical)
			{
                //pMultiBody->setupRevolute(i, linkMass, linkInertiaDiag, i - 1, btQuaternion(0.f, 0.f, 0.f, 1.f), hingeJointAxis, parentComToCurrentPivot, currentPivotToCurrentCom, false);
		
				if (i==0)
				{
				pMultiBody->setupRevolute(i, linkMass, linkInertiaDiag, i - 1, 
					btQuaternion(0.f, 0.f, 0.f, 1.f), 
					hingeJointAxis, 
					parentComToCurrentPivot, 
					currentPivotToCurrentCom, false);
				} else
				{
					btVector3 parentComToCurrentCom(0, -radius * 2.f, 0);						//par body's COM to cur body's COM offset
					btVector3 currentPivotToCurrentCom(0, -radius, 0);							//cur body's COM to cur body's PIV offset
					btVector3 parentComToCurrentPivot = parentComToCurrentCom - currentPivotToCurrentCom;	//par body's COM to cur body's PIV offset


					pMultiBody->setupFixed(i, linkMass, linkInertiaDiag, i - 1, 
					btQuaternion(0.f, 0.f, 0.f, 1.f), 
					parentComToCurrentPivot, 
					currentPivotToCurrentCom, false);
				}
					
				//pMultiBody->setupFixed(i,linkMass,linkInertiaDiag,i-1,btQuaternion(0,0,0,1),parentComToCurrentPivot,currentPivotToCurrentCom,false);
		
			}
            else
			{
                //pMultiBody->setupPlanar(i, linkMass, linkInertiaDiag, i - 1, btQuaternion(0.f, 0.f, 0.f, 1.f)/*quat0*/, btVector3(1, 0, 0), parentComToCurrentPivot*2, false);
                pMultiBody->setupSpherical(i, linkMass, linkInertiaDiag, i - 1, btQuaternion(0.f, 0.f, 0.f, 1.f), parentComToCurrentPivot, currentPivotToCurrentCom, false);
			}
        }

        pMultiBody->finalizeMultiDof();

		//for (int i=pMultiBody->getNumLinks()-1;i>=0;i--)//
			for (int i=0;i<pMultiBody->getNumLinks();i++)
		{
			btMultiBodyJointFeedback* fb = new btMultiBodyJointFeedback();
			pMultiBody->getLink(i).m_jointFeedback = fb;
			m_jointFeedbacks.push_back(fb);
			//break;
		}
        btMultiBodyDynamicsWorld* world = m_dynamicsWorld;

        ///
        world->addMultiBody(pMultiBody);
        btMultiBody* mbC = pMultiBody;
        mbC->setCanSleep(canSleep);
        mbC->setHasSelfCollision(selfCollide);
        mbC->setUseGyroTerm(gyro);
        //
        if(!damping)
        {
            mbC->setLinearDamping(0.f);
            mbC->setAngularDamping(0.f);
        }else
        {	mbC->setLinearDamping(0.1f);
            mbC->setAngularDamping(0.9f);
        }
        //
    	m_dynamicsWorld->setGravity(btVector3(0,0,-10));

        //////////////////////////////////////////////
        if(0)//numLinks > 0)
        {
            btScalar q0 = 45.f * SIMD_PI/ 180.f;
            if(!spherical)
                if(mbC->isMultiDof())
                    mbC->setJointPosMultiDof(0, &q0);
                else
                    mbC->setJointPos(0, q0);
            else
            {
                btQuaternion quat0(btVector3(1, 1, 0).normalized(), q0);
                quat0.normalize();
                mbC->setJointPosMultiDof(0, quat0);
            }
        }
        ///

        btAlignedObjectArray<btQuaternion> world_to_local;
        world_to_local.resize(pMultiBody->getNumLinks() + 1);

        btAlignedObjectArray<btVector3> local_origin;
        local_origin.resize(pMultiBody->getNumLinks() + 1);
        world_to_local[0] = pMultiBody->getWorldToBaseRot();
        local_origin[0] = pMultiBody->getBasePos();
      //  double friction = 1;
        {

        //	float pos[4]={local_origin[0].x(),local_origin[0].y(),local_origin[0].z(),1};
//            btScalar quat[4]={-world_to_local[0].x(),-world_to_local[0].y(),-world_to_local[0].z(),world_to_local[0].w()};


            if (1)
            {
                btCollisionShape* shape = new btBoxShape(btVector3(baseHalfExtents[0],baseHalfExtents[1],baseHalfExtents[2]));//new btSphereShape(baseHalfExtents[0]);
                m_guiHelper->createCollisionShapeGraphicsObject(shape);

                btMultiBodyLinkCollider* col= new btMultiBodyLinkCollider(pMultiBody, -1);
                col->setCollisionShape(shape);

                btTransform tr;
                tr.setIdentity();
//if we don't set the initial pose of the btCollisionObject, the simulator will do this 
				//when syncing the btMultiBody link transforms to the btMultiBodyLinkCollider
               
                tr.setOrigin(local_origin[0]);
				btQuaternion orn(btVector3(0,0,1),0.25*3.1415926538);
				
                tr.setRotation(orn);
                col->setWorldTransform(tr);

				bool isDynamic = (baseMass > 0 && floating);
				short collisionFilterGroup = isDynamic? short(btBroadphaseProxy::DefaultFilter) : short(btBroadphaseProxy::StaticFilter);
				short collisionFilterMask = isDynamic? 	short(btBroadphaseProxy::AllFilter) : 	short(btBroadphaseProxy::AllFilter ^ btBroadphaseProxy::StaticFilter);


                world->addCollisionObject(col,collisionFilterGroup,collisionFilterMask);//, 2,1+2);

                btVector3 color(0.0,0.0,0.5);
                m_guiHelper->createCollisionObjectGraphicsObject(col,color);

//                col->setFriction(friction);
                pMultiBody->setBaseCollider(col);

            }
        }


        for (int i=0; i < pMultiBody->getNumLinks(); ++i)
        {
            const int parent = pMultiBody->getParent(i);
            world_to_local[i+1] = pMultiBody->getParentToLocalRot(i) * world_to_local[parent+1];
            local_origin[i+1] = local_origin[parent+1] + (quatRotate(world_to_local[i+1].inverse() , pMultiBody->getRVector(i)));
        }


        for (int i=0; i < pMultiBody->getNumLinks(); ++i)
        {

            btVector3 posr = local_origin[i+1];
        //	float pos[4]={posr.x(),posr.y(),posr.z(),1};

            btScalar quat[4]={-world_to_local[i+1].x(),-world_to_local[i+1].y(),-world_to_local[i+1].z(),world_to_local[i+1].w()};
			btCollisionShape* shape =0;

			if (i==0)
			{
				shape = new btBoxShape(btVector3(linkHalfExtents[0],linkHalfExtents[1],linkHalfExtents[2]));//btSphereShape(linkHalfExtents[0]);
			} else
			{
				
				shape = new btSphereShape(radius);
			}

            m_guiHelper->createCollisionShapeGraphicsObject(shape);
            btMultiBodyLinkCollider* col = new btMultiBodyLinkCollider(pMultiBody, i);

            col->setCollisionShape(shape);
            btTransform tr;
            tr.setIdentity();
            tr.setOrigin(posr);
            tr.setRotation(btQuaternion(quat[0],quat[1],quat[2],quat[3]));
            col->setWorldTransform(tr);
     //       col->setFriction(friction);
			bool isDynamic = 1;//(linkMass > 0);
			short collisionFilterGroup = isDynamic? short(btBroadphaseProxy::DefaultFilter) : short(btBroadphaseProxy::StaticFilter);
			short collisionFilterMask = isDynamic? 	short(btBroadphaseProxy::AllFilter) : 	short(btBroadphaseProxy::AllFilter ^ btBroadphaseProxy::StaticFilter);

			//if (i==0||i>numLinks-2)
			{
				world->addCollisionObject(col,collisionFilterGroup,collisionFilterMask);//,2,1+2);
				   btVector4 color = colors[curColor];
			curColor++;
			curColor&=3;
            m_guiHelper->createCollisionObjectGraphicsObject(col,color);


            pMultiBody->getLink(i).m_collider=col;
			}
         
        }
    }

	btSerializer* s = new btDefaultSerializer;
	m_dynamicsWorld->serialize(s);
	b3ResourcePath p;
	char resourcePath[1024];
	if (p.findResourcePath("multibody.bullet",resourcePath,1024))
	{
		FILE* f = fopen(resourcePath,"wb");
		fwrite(s->getBufferPointer(),s->getCurrentBufferSize(),1,f);
		fclose(f);
	}
}
Пример #4
0
void ImportSDFSetup::initPhysics()
{

	int upAxis = 2;
	m_guiHelper->setUpAxis(upAxis);

	this->createEmptyDynamicsWorld();
	//m_dynamicsWorld->getSolverInfo().m_numIterations = 100;
    m_guiHelper->createPhysicsDebugDrawer(m_dynamicsWorld);
    m_dynamicsWorld->getDebugDrawer()->setDebugMode(
    btIDebugDraw::DBG_DrawConstraints
    +btIDebugDraw::DBG_DrawContactPoints
    +btIDebugDraw::DBG_DrawAabb
        );//+btIDebugDraw::DBG_DrawConstraintLimits);


	btVector3 gravity(0,0,0);
	gravity[upAxis]=-9.8;

	m_dynamicsWorld->setGravity(gravity);

    BulletURDFImporter u2b(m_guiHelper);
    
    bool loadOk =  u2b.loadSDF(m_fileName);


	if (loadOk)
	{
		//printTree(u2b,u2b.getRootLinkIndex());

		//u2b.printTree();

		btTransform identityTrans;
		identityTrans.setIdentity();


        
        for (int m =0; m<u2b.getNumModels();m++)
		{

            u2b.activateModel(m);
            
			btMultiBody* mb = 0;


			//todo: move these internal API called inside the 'ConvertURDF2Bullet' call, hidden from the user
			int rootLinkIndex = u2b.getRootLinkIndex();
			b3Printf("urdf root link index = %d\n",rootLinkIndex);
			MyMultiBodyCreator creation(m_guiHelper);

			ConvertURDF2Bullet(u2b,creation, identityTrans,m_dynamicsWorld,m_useMultiBody,u2b.getPathPrefix());
			mb = creation.getBulletMultiBody();
			
		}

	
        for (int i=0;i<m_dynamicsWorld->getNumMultiBodyConstraints();i++)
        {
            m_dynamicsWorld->getMultiBodyConstraint(i)->finalizeMultiDof();
        }



		bool createGround=true;
		if (createGround)
		{
			btVector3 groundHalfExtents(20,20,20);
			groundHalfExtents[upAxis]=1.f;
			btBoxShape* box = new btBoxShape(groundHalfExtents);
			box->initializePolyhedralFeatures();

			m_guiHelper->createCollisionShapeGraphicsObject(box);
			btTransform start; start.setIdentity();
			btVector3 groundOrigin(0,0,0);
			groundOrigin[upAxis]=-2.5;
			start.setOrigin(groundOrigin);
			btRigidBody* body =  createRigidBody(0,start,box);
			//m_dynamicsWorld->removeRigidBody(body);
		   // m_dynamicsWorld->addRigidBody(body,2,1);
			btVector3 color(0.5,0.5,0.5);
			m_guiHelper->createRigidBodyGraphicsObject(body,color);
		}

		///this extra stepSimulation call makes sure that all the btMultibody transforms are properly propagates.
		m_dynamicsWorld->stepSimulation(1. / 240., 0);// 1., 10, 1. / 240.);
	}


}
Пример #5
0
void ImportSDFSetup::initPhysics()
{
	int upAxis = 2;
	m_guiHelper->setUpAxis(upAxis);

	this->createEmptyDynamicsWorld();
	//m_dynamicsWorld->getSolverInfo().m_numIterations = 100;
	m_guiHelper->createPhysicsDebugDrawer(m_dynamicsWorld);
	m_dynamicsWorld->getDebugDrawer()->setDebugMode(
		btIDebugDraw::DBG_DrawConstraints + btIDebugDraw::DBG_DrawContactPoints + btIDebugDraw::DBG_DrawAabb);  //+btIDebugDraw::DBG_DrawConstraintLimits);

	btVector3 gravity(0, 0, 0);
	gravity[upAxis] = -9.8;

	m_dynamicsWorld->setGravity(gravity);

	BulletURDFImporter u2b(m_guiHelper, 0, 0, 1, 0);

	bool loadOk = u2b.loadSDF(m_fileName);

	if (loadOk)
	{
		//printTree(u2b,u2b.getRootLinkIndex());

		//u2b.printTree();

		btTransform rootTrans;
		rootTrans.setIdentity();

		for (int m = 0; m < u2b.getNumModels(); m++)
		{
			u2b.activateModel(m);

			btMultiBody* mb = 0;

			//todo: move these internal API called inside the 'ConvertURDF2Bullet' call, hidden from the user
			//int rootLinkIndex = u2b.getRootLinkIndex();
			//b3Printf("urdf root link index = %d\n",rootLinkIndex);
			MyMultiBodyCreator creation(m_guiHelper);

			u2b.getRootTransformInWorld(rootTrans);
			ConvertURDF2Bullet(u2b, creation, rootTrans, m_dynamicsWorld, m_useMultiBody, u2b.getPathPrefix(), CUF_USE_SDF);
			mb = creation.getBulletMultiBody();

			if (m_useMultiBody && mb)
			{
				std::string* name = new std::string(u2b.getLinkName(u2b.getRootLinkIndex()));
				m_nameMemory.push_back(name);
#ifdef TEST_MULTIBODY_SERIALIZATION
				s->registerNameForPointer(name->c_str(), name->c_str());
#endif  //TEST_MULTIBODY_SERIALIZATION
				mb->setBaseName(name->c_str());
				//create motors for each btMultiBody joint
				int numLinks = mb->getNumLinks();
				for (int i = 0; i < numLinks; i++)
				{
					int mbLinkIndex = i;
					int urdfLinkIndex = creation.m_mb2urdfLink[mbLinkIndex];

					std::string* jointName = new std::string(u2b.getJointName(urdfLinkIndex));
					std::string* linkName = new std::string(u2b.getLinkName(urdfLinkIndex).c_str());
#ifdef TEST_MULTIBODY_SERIALIZATION
					s->registerNameForPointer(jointName->c_str(), jointName->c_str());
					s->registerNameForPointer(linkName->c_str(), linkName->c_str());
#endif  //TEST_MULTIBODY_SERIALIZATION
					m_nameMemory.push_back(jointName);
					m_nameMemory.push_back(linkName);

					mb->getLink(i).m_linkName = linkName->c_str();
					mb->getLink(i).m_jointName = jointName->c_str();

					if (mb->getLink(mbLinkIndex).m_jointType == btMultibodyLink::eRevolute || mb->getLink(mbLinkIndex).m_jointType == btMultibodyLink::ePrismatic)
					{
						if (m_data->m_numMotors < MAX_NUM_MOTORS)
						{
							char motorName[1024];
							sprintf(motorName, "%s q'", jointName->c_str());
							btScalar* motorVel = &m_data->m_motorTargetVelocities[m_data->m_numMotors];
							*motorVel = 0.f;
							SliderParams slider(motorName, motorVel);
							slider.m_minVal = -4;
							slider.m_maxVal = 4;
							m_guiHelper->getParameterInterface()->registerSliderFloatParameter(slider);
							float maxMotorImpulse = 10.1f;
							btMultiBodyJointMotor* motor = new btMultiBodyJointMotor(mb, mbLinkIndex, 0, 0, maxMotorImpulse);
							//motor->setMaxAppliedImpulse(0);
							m_data->m_jointMotors[m_data->m_numMotors] = motor;
							m_dynamicsWorld->addMultiBodyConstraint(motor);
							m_data->m_numMotors++;
						}
					}
				}
			}
		}

		for (int i = 0; i < m_dynamicsWorld->getNumMultiBodyConstraints(); i++)
		{
			m_dynamicsWorld->getMultiBodyConstraint(i)->finalizeMultiDof();
		}

		bool createGround = true;
		if (createGround)
		{
			btVector3 groundHalfExtents(20, 20, 20);
			groundHalfExtents[upAxis] = 1.f;
			btBoxShape* box = new btBoxShape(groundHalfExtents);
			box->initializePolyhedralFeatures();

			m_guiHelper->createCollisionShapeGraphicsObject(box);
			btTransform start;
			start.setIdentity();
			btVector3 groundOrigin(0, 0, 0);
			groundOrigin[upAxis] = -2.5;
			start.setOrigin(groundOrigin);
			btRigidBody* body = createRigidBody(0, start, box);
			//m_dynamicsWorld->removeRigidBody(body);
			// m_dynamicsWorld->addRigidBody(body,2,1);
			btVector3 color(0.5, 0.5, 0.5);
			m_guiHelper->createRigidBodyGraphicsObject(body, color);
		}

		///this extra stepSimulation call makes sure that all the btMultibody transforms are properly propagates.
		m_dynamicsWorld->stepSimulation(1. / 240., 0);  // 1., 10, 1. / 240.);
	}
}
void MultiBodySoftContact::initPhysics()
{
	  
    int upAxis = 2;

	m_guiHelper->setUpAxis(upAxis);

    btVector4 colors[4] =
    {
        btVector4(1,0,0,1),
        btVector4(0,1,0,1),
        btVector4(0,1,1,1),
        btVector4(1,1,0,1),
    };
    int curColor = 0;


    

	this->createEmptyDynamicsWorld();
		m_dynamicsWorld->setGravity(btVector3(0,0,-10));

	m_guiHelper->createPhysicsDebugDrawer(m_dynamicsWorld);
    m_dynamicsWorld->getDebugDrawer()->setDebugMode(
        //btIDebugDraw::DBG_DrawConstraints
        +btIDebugDraw::DBG_DrawWireframe
        +btIDebugDraw::DBG_DrawContactPoints
        +btIDebugDraw::DBG_DrawAabb
        );//+btIDebugDraw::DBG_DrawConstraintLimits);

	

    //create a static ground object
    if (1)
        {
            btVector3 groundHalfExtents(50,50,50);
            btBoxShape* box = new btBoxShape(groundHalfExtents);
            box->initializePolyhedralFeatures();

            m_guiHelper->createCollisionShapeGraphicsObject(box);
            btTransform start; start.setIdentity();
            btVector3 groundOrigin(0,0,-50.5);
			start.setOrigin(groundOrigin);
		//	start.setRotation(groundOrn);
            btRigidBody* body =  createRigidBody(0,start,box);
            
            //setContactStiffnessAndDamping will enable compliant rigid body contact
            body->setContactStiffnessAndDamping(300,10);
            btVector4 color = colors[curColor];
			curColor++;
			curColor&=3;
            m_guiHelper->createRigidBodyGraphicsObject(body,color);

        }

	{
		btCollisionShape* childShape = new btSphereShape(btScalar(0.5));
		m_guiHelper->createCollisionShapeGraphicsObject(childShape);

		btScalar mass = 1;
		btVector3 baseInertiaDiag;
		bool isFixed = (mass == 0);
		childShape->calculateLocalInertia(mass,baseInertiaDiag);
	  btMultiBody *pMultiBody = new btMultiBody(0, 1, baseInertiaDiag, false, false);
	  btTransform startTrans;
	  startTrans.setIdentity();
	  startTrans.setOrigin(btVector3(0,0,3));

	  pMultiBody->setBaseWorldTransform(startTrans);

	   btMultiBodyLinkCollider* col= new btMultiBodyLinkCollider(pMultiBody, -1);
		col->setCollisionShape(childShape);
		pMultiBody->setBaseCollider(col);
			bool isDynamic = (mass > 0 && !isFixed);
		int collisionFilterGroup = isDynamic? int(btBroadphaseProxy::DefaultFilter) : int(btBroadphaseProxy::StaticFilter);
		int collisionFilterMask = isDynamic? 	int(btBroadphaseProxy::AllFilter) : 	int(btBroadphaseProxy::AllFilter ^ btBroadphaseProxy::StaticFilter);

        m_dynamicsWorld->addCollisionObject(col,collisionFilterGroup,collisionFilterMask);//, 2,1+2);


		pMultiBody->finalizeMultiDof();
	
		m_dynamicsWorld->addMultiBody(pMultiBody);
	
		btAlignedObjectArray<btQuaternion> scratch_q;
		btAlignedObjectArray<btVector3> scratch_m;
		pMultiBody->forwardKinematics(scratch_q,scratch_m);
		btAlignedObjectArray<btQuaternion> world_to_local;
		btAlignedObjectArray<btVector3> local_origin;
		pMultiBody->updateCollisionObjectWorldTransforms(world_to_local,local_origin);
	}
	m_guiHelper->autogenerateGraphicsObjects(m_dynamicsWorld);


}
void TestJointTorqueSetup::initPhysics()
{
    int upAxis = 2;
	m_guiHelper->setUpAxis(upAxis);

    btVector4 colors[4] =
    {
        btVector4(1,0,0,1),
        btVector4(0,1,0,1),
        btVector4(0,1,1,1),
        btVector4(1,1,0,1),
    };
    int curColor = 0;



    

	this->createEmptyDynamicsWorld();
    m_guiHelper->createPhysicsDebugDrawer(m_dynamicsWorld);
    m_dynamicsWorld->getDebugDrawer()->setDebugMode(
        //btIDebugDraw::DBG_DrawConstraints
        +btIDebugDraw::DBG_DrawWireframe
        +btIDebugDraw::DBG_DrawContactPoints
        +btIDebugDraw::DBG_DrawAabb
        );//+btIDebugDraw::DBG_DrawConstraintLimits);

    //create a static ground object
    if (0)
        {
            btVector3 groundHalfExtents(20,20,20);
            groundHalfExtents[upAxis]=1.f;
            btBoxShape* box = new btBoxShape(groundHalfExtents);
            box->initializePolyhedralFeatures();

            m_guiHelper->createCollisionShapeGraphicsObject(box);
            btTransform start; start.setIdentity();
            btVector3 groundOrigin(0,0,0);
            groundOrigin[upAxis]=-1.5;
            start.setOrigin(groundOrigin);
            btRigidBody* body =  createRigidBody(0,start,box);
            btVector4 color = colors[curColor];
			curColor++;
			curColor&=3;
            m_guiHelper->createRigidBodyGraphicsObject(body,color);
        }

    {
        bool floating = false;
        bool damping = true;
        bool gyro = true;
        int numLinks = 5;
        bool spherical = false;					//set it ot false -to use 1DoF hinges instead of 3DoF sphericals
        bool canSleep = false;
        bool selfCollide = false;
        btVector3 linkHalfExtents(0.05, 0.37, 0.1);
        btVector3 baseHalfExtents(0.05, 0.37, 0.1);

        btVector3 basePosition = btVector3(-0.4f, 3.f, 0.f);
        //mbC->forceMultiDof();							//if !spherical, you can comment this line to check the 1DoF algorithm
        //init the base
        btVector3 baseInertiaDiag(0.f, 0.f, 0.f);
        float baseMass = 1.f;

        if(baseMass)
        {
            btCollisionShape *pTempBox = new btBoxShape(btVector3(baseHalfExtents[0], baseHalfExtents[1], baseHalfExtents[2]));
            pTempBox->calculateLocalInertia(baseMass, baseInertiaDiag);
            delete pTempBox;
        }

        bool isMultiDof = false;
        btMultiBody *pMultiBody = new btMultiBody(numLinks, baseMass, baseInertiaDiag, !floating, canSleep, isMultiDof);
        m_multiBody = pMultiBody;
        btQuaternion baseOriQuat(0.f, 0.f, 0.f, 1.f);
        pMultiBody->setBasePos(basePosition);
        pMultiBody->setWorldToBaseRot(baseOriQuat);
        btVector3 vel(0, 0, 0);
    //	pMultiBody->setBaseVel(vel);

        //init the links
        btVector3 hingeJointAxis(1, 0, 0);
        float linkMass = 1.f;
        btVector3 linkInertiaDiag(0.f, 0.f, 0.f);

        btCollisionShape *pTempBox = new btBoxShape(btVector3(linkHalfExtents[0], linkHalfExtents[1], linkHalfExtents[2]));
        pTempBox->calculateLocalInertia(linkMass, linkInertiaDiag);
        delete pTempBox;

        //y-axis assumed up
        btVector3 parentComToCurrentCom(0, -linkHalfExtents[1] * 2.f, 0);						//par body's COM to cur body's COM offset
        btVector3 currentPivotToCurrentCom(0, -linkHalfExtents[1], 0);							//cur body's COM to cur body's PIV offset
        btVector3 parentComToCurrentPivot = parentComToCurrentCom - currentPivotToCurrentCom;	//par body's COM to cur body's PIV offset

        //////
        btScalar q0 = 0.f * SIMD_PI/ 180.f;
        btQuaternion quat0(btVector3(0, 1, 0).normalized(), q0);
        quat0.normalize();
        /////

        for(int i = 0; i < numLinks; ++i)
        {
            if(!spherical)
                pMultiBody->setupRevolute(i, linkMass, linkInertiaDiag, i - 1, btQuaternion(0.f, 0.f, 0.f, 1.f), hingeJointAxis, parentComToCurrentPivot, currentPivotToCurrentCom, false);
            else
                //pMultiBody->setupPlanar(i, linkMass, linkInertiaDiag, i - 1, btQuaternion(0.f, 0.f, 0.f, 1.f)/*quat0*/, btVector3(1, 0, 0), parentComToCurrentPivot*2, false);
                pMultiBody->setupSpherical(i, linkMass, linkInertiaDiag, i - 1, btQuaternion(0.f, 0.f, 0.f, 1.f), parentComToCurrentPivot, currentPivotToCurrentCom, false);
        }

        //pMultiBody->finalizeMultiDof();

        btMultiBodyDynamicsWorld* world = m_dynamicsWorld;

        ///
        world->addMultiBody(pMultiBody);
        btMultiBody* mbC = pMultiBody;
        mbC->setCanSleep(canSleep);
        mbC->setHasSelfCollision(selfCollide);
        mbC->setUseGyroTerm(gyro);
        //
        if(!damping)
        {
            mbC->setLinearDamping(0.f);
            mbC->setAngularDamping(0.f);
        }else
        {	mbC->setLinearDamping(0.1f);
            mbC->setAngularDamping(0.9f);
        }
        //
        btVector3 gravity(0,0,0);
        //gravity[upAxis] = -9.81;
        m_dynamicsWorld->setGravity(gravity);
        //////////////////////////////////////////////
        if(numLinks > 0)
        {
            btScalar q0 = 45.f * SIMD_PI/ 180.f;
            if(!spherical)
                if(mbC->isMultiDof())
                    mbC->setJointPosMultiDof(0, &q0);
                else
                    mbC->setJointPos(0, q0);
            else
            {
                btQuaternion quat0(btVector3(1, 1, 0).normalized(), q0);
                quat0.normalize();
                mbC->setJointPosMultiDof(0, quat0);
            }
        }
        ///

        btAlignedObjectArray<btQuaternion> world_to_local;
        world_to_local.resize(pMultiBody->getNumLinks() + 1);

        btAlignedObjectArray<btVector3> local_origin;
        local_origin.resize(pMultiBody->getNumLinks() + 1);
        world_to_local[0] = pMultiBody->getWorldToBaseRot();
        local_origin[0] = pMultiBody->getBasePos();
        double friction = 1;
        {

        //	float pos[4]={local_origin[0].x(),local_origin[0].y(),local_origin[0].z(),1};
            float quat[4]={-world_to_local[0].x(),-world_to_local[0].y(),-world_to_local[0].z(),world_to_local[0].w()};


            if (1)
            {
                btCollisionShape* box = new btBoxShape(baseHalfExtents);
                m_guiHelper->createCollisionShapeGraphicsObject(box);

                btMultiBodyLinkCollider* col= new btMultiBodyLinkCollider(pMultiBody, -1);
                col->setCollisionShape(box);

                btTransform tr;
                tr.setIdentity();
//if we don't set the initial pose of the btCollisionObject, the simulator will do this 
				//when syncing the btMultiBody link transforms to the btMultiBodyLinkCollider
               
                tr.setOrigin(local_origin[0]);
                tr.setRotation(btQuaternion(quat[0],quat[1],quat[2],quat[3]));
                col->setWorldTransform(tr);

                world->addCollisionObject(col, 2,1+2);

                btVector3 color(0.0,0.0,0.5);
                m_guiHelper->createCollisionObjectGraphicsObject(col,color);

                col->setFriction(friction);
                pMultiBody->setBaseCollider(col);

            }
        }


        for (int i=0; i < pMultiBody->getNumLinks(); ++i)
        {
            const int parent = pMultiBody->getParent(i);
            world_to_local[i+1] = pMultiBody->getParentToLocalRot(i) * world_to_local[parent+1];
            local_origin[i+1] = local_origin[parent+1] + (quatRotate(world_to_local[i+1].inverse() , pMultiBody->getRVector(i)));
        }


        for (int i=0; i < pMultiBody->getNumLinks(); ++i)
        {

            btVector3 posr = local_origin[i+1];
        //	float pos[4]={posr.x(),posr.y(),posr.z(),1};

            float quat[4]={-world_to_local[i+1].x(),-world_to_local[i+1].y(),-world_to_local[i+1].z(),world_to_local[i+1].w()};

            btCollisionShape* box = new btBoxShape(linkHalfExtents);
            m_guiHelper->createCollisionShapeGraphicsObject(box);
            btMultiBodyLinkCollider* col = new btMultiBodyLinkCollider(pMultiBody, i);

            col->setCollisionShape(box);
            btTransform tr;
            tr.setIdentity();
            tr.setOrigin(posr);
            tr.setRotation(btQuaternion(quat[0],quat[1],quat[2],quat[3]));
            col->setWorldTransform(tr);
            col->setFriction(friction);
            world->addCollisionObject(col,2,1+2);
            btVector4 color = colors[curColor];
			curColor++;
			curColor&=3;
            m_guiHelper->createCollisionObjectGraphicsObject(col,color);


            pMultiBody->getLink(i).m_collider=col;
        }
    }

}
Пример #8
0
void TestHingeTorque::initPhysics()
{
	int upAxis = 1;
	m_guiHelper->setUpAxis(upAxis);

	createEmptyDynamicsWorld();
	m_dynamicsWorld->getSolverInfo().m_splitImpulse = false;
	
    m_dynamicsWorld->setGravity(btVector3(0,0,-10));
    
	m_guiHelper->createPhysicsDebugDrawer(m_dynamicsWorld);
	int mode = 	btIDebugDraw::DBG_DrawWireframe
				+btIDebugDraw::DBG_DrawConstraints
				+btIDebugDraw::DBG_DrawConstraintLimits;
	m_dynamicsWorld->getDebugDrawer()->setDebugMode(mode);


	{ // create a door using hinge constraint attached to the world
        
        int numLinks = 2;
        bool spherical = false;					//set it ot false -to use 1DoF hinges instead of 3DoF sphericals
        bool canSleep = false;
        bool selfCollide = false;
        btVector3 linkHalfExtents(0.05, 0.37, 0.1);
        btVector3 baseHalfExtents(0.05, 0.37, 0.1);

        btBoxShape* baseBox = new btBoxShape(baseHalfExtents);
        btVector3 basePosition = btVector3(-0.4f, 3.f, 0.f);
        btTransform baseWorldTrans;
        baseWorldTrans.setIdentity();
        baseWorldTrans.setOrigin(basePosition);
        
        //mbC->forceMultiDof();							//if !spherical, you can comment this line to check the 1DoF algorithm
        //init the base
        btVector3 baseInertiaDiag(0.f, 0.f, 0.f);
        float baseMass = 0.f;
        float linkMass = 1.f;
        
        btRigidBody* base = createRigidBody(baseMass,baseWorldTrans,baseBox);
        m_dynamicsWorld->removeRigidBody(base);
        base->setDamping(0,0);
        m_dynamicsWorld->addRigidBody(base,collisionFilterGroup,collisionFilterMask);
        btBoxShape* linkBox1 = new btBoxShape(linkHalfExtents);
		btSphereShape* linkSphere = new btSphereShape(radius);
		
        btRigidBody* prevBody = base;
        
        for (int i=0;i<numLinks;i++)
        {
            btTransform linkTrans;
            linkTrans = baseWorldTrans;
            
            linkTrans.setOrigin(basePosition-btVector3(0,linkHalfExtents[1]*2.f*(i+1),0));
            
			btCollisionShape* colOb = 0;
			
			if (i==0)
			{
				colOb = linkBox1;
			} else 
			{
				colOb = linkSphere;
			}
            btRigidBody* linkBody = createRigidBody(linkMass,linkTrans,colOb);
            m_dynamicsWorld->removeRigidBody(linkBody);
            m_dynamicsWorld->addRigidBody(linkBody,collisionFilterGroup,collisionFilterMask);
            linkBody->setDamping(0,0);
			btTypedConstraint* con = 0;
			
			if (i==0)
			{
				//create a hinge constraint
				btVector3 pivotInA(0,-linkHalfExtents[1],0);
				btVector3 pivotInB(0,linkHalfExtents[1],0);
				btVector3 axisInA(1,0,0);
				btVector3 axisInB(1,0,0);
				bool useReferenceA = true;
				btHingeConstraint* hinge = new btHingeConstraint(*prevBody,*linkBody,
																 pivotInA,pivotInB,
																 axisInA,axisInB,useReferenceA);
				con = hinge;
			} else
			{
				
				btTransform pivotInA(btQuaternion::getIdentity(),btVector3(0, -radius, 0));						//par body's COM to cur body's COM offset
				btTransform pivotInB(btQuaternion::getIdentity(),btVector3(0, radius, 0));							//cur body's COM to cur body's PIV offset
				btGeneric6DofSpring2Constraint* fixed = new btGeneric6DofSpring2Constraint(*prevBody, *linkBody,
																						   pivotInA,pivotInB);
				fixed->setLinearLowerLimit(btVector3(0,0,0));
				fixed->setLinearUpperLimit(btVector3(0,0,0));
				fixed->setAngularLowerLimit(btVector3(0,0,0));
				fixed->setAngularUpperLimit(btVector3(0,0,0));
				
				con = fixed;

			}
			btAssert(con);
			if (con)
			{
				btJointFeedback* fb = new btJointFeedback();
				m_jointFeedback.push_back(fb);
				con->setJointFeedback(fb);

				m_dynamicsWorld->addConstraint(con,true);
			}
			prevBody = linkBody;
            
        }
       
	}
	
	if (1)
	{
		btVector3 groundHalfExtents(1,1,0.2);
		groundHalfExtents[upAxis]=1.f;
		btBoxShape* box = new btBoxShape(groundHalfExtents);
		box->initializePolyhedralFeatures();
		
		btTransform start; start.setIdentity();
		btVector3 groundOrigin(-0.4f, 3.f, 0.f);
		btVector3 basePosition = btVector3(-0.4f, 3.f, 0.f);
		btQuaternion groundOrn(btVector3(0,1,0),0.25*SIMD_PI);
		
		groundOrigin[upAxis] -=.5;
		groundOrigin[2]-=0.6;
		start.setOrigin(groundOrigin);
	//	start.setRotation(groundOrn);
		btRigidBody* body =  createRigidBody(0,start,box);
		body->setFriction(0);
		
	}
	m_guiHelper->autogenerateGraphicsObjects(m_dynamicsWorld);
}