773 lines
		
	
	
		
			21 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			773 lines
		
	
	
		
			21 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| /*
 | |
|  * Copyright (c) 2005 Erwin Coumans http://continuousphysics.com/Bullet/
 | |
|  *
 | |
|  * Permission to use, copy, modify, distribute and sell this software
 | |
|  * and its documentation for any purpose is hereby granted without fee,
 | |
|  * provided that the above copyright notice appear in all copies.
 | |
|  * Erwin Coumans makes no representations about the suitability 
 | |
|  * of this software for any purpose.  
 | |
|  * It is provided "as is" without express or implied warranty.
 | |
| */
 | |
| 
 | |
| #include "LinearMath/btVector3.h"
 | |
| #include "btRaycastVehicle.h"
 | |
| 
 | |
| #include "BulletDynamics/ConstraintSolver/btSolve2LinearConstraint.h"
 | |
| #include "BulletDynamics/ConstraintSolver/btJacobianEntry.h"
 | |
| #include "LinearMath/btQuaternion.h"
 | |
| #include "BulletDynamics/Dynamics/btDynamicsWorld.h"
 | |
| #include "btVehicleRaycaster.h"
 | |
| #include "btWheelInfo.h"
 | |
| #include "LinearMath/btMinMax.h"
 | |
| #include "LinearMath/btIDebugDraw.h"
 | |
| #include "BulletDynamics/ConstraintSolver/btContactConstraint.h"
 | |
| 
 | |
| #define ROLLING_INFLUENCE_FIX
 | |
| 
 | |
| 
 | |
| btRigidBody& btActionInterface::getFixedBody()
 | |
| {
 | |
| 	static btRigidBody s_fixed(0, 0,0);
 | |
| 	s_fixed.setMassProps(btScalar(0.),btVector3(btScalar(0.),btScalar(0.),btScalar(0.)));
 | |
| 	return s_fixed;
 | |
| }
 | |
| 
 | |
| btRaycastVehicle::btRaycastVehicle(const btVehicleTuning& tuning,btRigidBody* chassis,	btVehicleRaycaster* raycaster )
 | |
| :m_vehicleRaycaster(raycaster),
 | |
| m_pitchControl(btScalar(0.))
 | |
| {
 | |
| 	m_chassisBody = chassis;
 | |
| 	m_indexRightAxis = 0;
 | |
| 	m_indexUpAxis = 2;
 | |
| 	m_indexForwardAxis = 1;
 | |
| 	defaultInit(tuning);
 | |
| }
 | |
| 
 | |
| 
 | |
| void btRaycastVehicle::defaultInit(const btVehicleTuning& tuning)
 | |
| {
 | |
| 	(void)tuning;
 | |
| 	m_currentVehicleSpeedKmHour = btScalar(0.);
 | |
| 	m_steeringValue = btScalar(0.);
 | |
| 	
 | |
| }
 | |
| 
 | |
| 	
 | |
| 
 | |
| btRaycastVehicle::~btRaycastVehicle()
 | |
| {
 | |
| }
 | |
| 
 | |
| 
 | |
| //
 | |
| // basically most of the code is general for 2 or 4 wheel vehicles, but some of it needs to be reviewed
 | |
| //
 | |
| btWheelInfo&	btRaycastVehicle::addWheel( const btVector3& connectionPointCS, const btVector3& wheelDirectionCS0,const btVector3& wheelAxleCS, btScalar suspensionRestLength, btScalar wheelRadius,const btVehicleTuning& tuning, bool isFrontWheel)
 | |
| {
 | |
| 
 | |
| 	btWheelInfoConstructionInfo ci;
 | |
| 
 | |
| 	ci.m_chassisConnectionCS = connectionPointCS;
 | |
| 	ci.m_wheelDirectionCS = wheelDirectionCS0;
 | |
| 	ci.m_wheelAxleCS = wheelAxleCS;
 | |
| 	ci.m_suspensionRestLength = suspensionRestLength;
 | |
| 	ci.m_wheelRadius = wheelRadius;
 | |
| 	ci.m_suspensionStiffness = tuning.m_suspensionStiffness;
 | |
| 	ci.m_wheelsDampingCompression = tuning.m_suspensionCompression;
 | |
| 	ci.m_wheelsDampingRelaxation = tuning.m_suspensionDamping;
 | |
| 	ci.m_frictionSlip = tuning.m_frictionSlip;
 | |
| 	ci.m_bIsFrontWheel = isFrontWheel;
 | |
| 	ci.m_maxSuspensionTravelCm = tuning.m_maxSuspensionTravelCm;
 | |
| 	ci.m_maxSuspensionForce = tuning.m_maxSuspensionForce;
 | |
| 
 | |
| 	m_wheelInfo.push_back( btWheelInfo(ci));
 | |
| 	
 | |
| 	btWheelInfo& wheel = m_wheelInfo[getNumWheels()-1];
 | |
| 	
 | |
| 	updateWheelTransformsWS( wheel , false );
 | |
| 	updateWheelTransform(getNumWheels()-1,false);
 | |
| 	return wheel;
 | |
| }
 | |
| 
 | |
| 
 | |
| 
 | |
| 
 | |
| const btTransform&	btRaycastVehicle::getWheelTransformWS( int wheelIndex ) const
 | |
| {
 | |
| 	btAssert(wheelIndex < getNumWheels());
 | |
| 	const btWheelInfo& wheel = m_wheelInfo[wheelIndex];
 | |
| 	return wheel.m_worldTransform;
 | |
| 
 | |
| }
 | |
| 
 | |
| void	btRaycastVehicle::updateWheelTransform( int wheelIndex , bool interpolatedTransform)
 | |
| {
 | |
| 	
 | |
| 	btWheelInfo& wheel = m_wheelInfo[ wheelIndex ];
 | |
| 	updateWheelTransformsWS(wheel,interpolatedTransform);
 | |
| 	btVector3 up = -wheel.m_raycastInfo.m_wheelDirectionWS;
 | |
| 	const btVector3& right = wheel.m_raycastInfo.m_wheelAxleWS;
 | |
| 	btVector3 fwd = up.cross(right);
 | |
| 	fwd = fwd.normalize();
 | |
| //	up = right.cross(fwd);
 | |
| //	up.normalize();
 | |
| 
 | |
| 	//rotate around steering over de wheelAxleWS
 | |
| 	btScalar steering = wheel.m_steering;
 | |
| 	
 | |
| 	btQuaternion steeringOrn(up,steering);//wheel.m_steering);
 | |
| 	btMatrix3x3 steeringMat(steeringOrn);
 | |
| 
 | |
| 	btQuaternion rotatingOrn(right,-wheel.m_rotation);
 | |
| 	btMatrix3x3 rotatingMat(rotatingOrn);
 | |
| 
 | |
| 	btMatrix3x3 basis2(
 | |
| 		right[0],fwd[0],up[0],
 | |
| 		right[1],fwd[1],up[1],
 | |
| 		right[2],fwd[2],up[2]
 | |
| 	);
 | |
| 	
 | |
| 	wheel.m_worldTransform.setBasis(steeringMat * rotatingMat * basis2);
 | |
| 	wheel.m_worldTransform.setOrigin(
 | |
| 		wheel.m_raycastInfo.m_hardPointWS + wheel.m_raycastInfo.m_wheelDirectionWS * wheel.m_raycastInfo.m_suspensionLength
 | |
| 	);
 | |
| }
 | |
| 
 | |
| void btRaycastVehicle::resetSuspension()
 | |
| {
 | |
| 
 | |
| 	int i;
 | |
| 	for (i=0;i<m_wheelInfo.size();	i++)
 | |
| 	{
 | |
| 			btWheelInfo& wheel = m_wheelInfo[i];
 | |
| 			wheel.m_raycastInfo.m_suspensionLength = wheel.getSuspensionRestLength();
 | |
| 			wheel.m_suspensionRelativeVelocity = btScalar(0.0);
 | |
| 			
 | |
| 			wheel.m_raycastInfo.m_contactNormalWS = - wheel.m_raycastInfo.m_wheelDirectionWS;
 | |
| 			//wheel_info.setContactFriction(btScalar(0.0));
 | |
| 			wheel.m_clippedInvContactDotSuspension = btScalar(1.0);
 | |
| 	}
 | |
| }
 | |
| 
 | |
| void	btRaycastVehicle::updateWheelTransformsWS(btWheelInfo& wheel , bool interpolatedTransform)
 | |
| {
 | |
| 	wheel.m_raycastInfo.m_isInContact = false;
 | |
| 
 | |
| 	btTransform chassisTrans = getChassisWorldTransform();
 | |
| 	if (interpolatedTransform && (getRigidBody()->getMotionState()))
 | |
| 	{
 | |
| 		getRigidBody()->getMotionState()->getWorldTransform(chassisTrans);
 | |
| 	}
 | |
| 
 | |
| 	wheel.m_raycastInfo.m_hardPointWS = chassisTrans( wheel.m_chassisConnectionPointCS );
 | |
| 	wheel.m_raycastInfo.m_wheelDirectionWS = chassisTrans.getBasis() *  wheel.m_wheelDirectionCS ;
 | |
| 	wheel.m_raycastInfo.m_wheelAxleWS = chassisTrans.getBasis() * wheel.m_wheelAxleCS;
 | |
| }
 | |
| 
 | |
| btScalar btRaycastVehicle::rayCast(btWheelInfo& wheel)
 | |
| {
 | |
| 	updateWheelTransformsWS( wheel,false);
 | |
| 
 | |
| 	
 | |
| 	btScalar depth = -1;
 | |
| 	
 | |
| 	btScalar raylen = wheel.getSuspensionRestLength()+wheel.m_wheelsRadius;
 | |
| 
 | |
| 	btVector3 rayvector = wheel.m_raycastInfo.m_wheelDirectionWS * (raylen);
 | |
| 	const btVector3& source = wheel.m_raycastInfo.m_hardPointWS;
 | |
| 	wheel.m_raycastInfo.m_contactPointWS = source + rayvector;
 | |
| 	const btVector3& target = wheel.m_raycastInfo.m_contactPointWS;
 | |
| 
 | |
| 	btScalar param = btScalar(0.);
 | |
| 	
 | |
| 	btVehicleRaycaster::btVehicleRaycasterResult	rayResults;
 | |
| 
 | |
| 	btAssert(m_vehicleRaycaster);
 | |
| 
 | |
| 	void* object = m_vehicleRaycaster->castRay(source,target,rayResults);
 | |
| 
 | |
| 	wheel.m_raycastInfo.m_groundObject = 0;
 | |
| 
 | |
| 	if (object)
 | |
| 	{
 | |
| 		param = rayResults.m_distFraction;
 | |
| 		depth = raylen * rayResults.m_distFraction;
 | |
| 		wheel.m_raycastInfo.m_contactNormalWS  = rayResults.m_hitNormalInWorld;
 | |
| 		wheel.m_raycastInfo.m_isInContact = true;
 | |
| 		
 | |
| 		wheel.m_raycastInfo.m_groundObject = &getFixedBody();///@todo for driving on dynamic/movable objects!;
 | |
| 		//wheel.m_raycastInfo.m_groundObject = object;
 | |
| 
 | |
| 
 | |
| 		btScalar hitDistance = param*raylen;
 | |
| 		wheel.m_raycastInfo.m_suspensionLength = hitDistance - wheel.m_wheelsRadius;
 | |
| 		//clamp on max suspension travel
 | |
| 
 | |
| 		btScalar  minSuspensionLength = wheel.getSuspensionRestLength() - wheel.m_maxSuspensionTravelCm*btScalar(0.01);
 | |
| 		btScalar maxSuspensionLength = wheel.getSuspensionRestLength()+ wheel.m_maxSuspensionTravelCm*btScalar(0.01);
 | |
| 		if (wheel.m_raycastInfo.m_suspensionLength < minSuspensionLength)
 | |
| 		{
 | |
| 			wheel.m_raycastInfo.m_suspensionLength = minSuspensionLength;
 | |
| 		}
 | |
| 		if (wheel.m_raycastInfo.m_suspensionLength > maxSuspensionLength)
 | |
| 		{
 | |
| 			wheel.m_raycastInfo.m_suspensionLength = maxSuspensionLength;
 | |
| 		}
 | |
| 
 | |
| 		wheel.m_raycastInfo.m_contactPointWS = rayResults.m_hitPointInWorld;
 | |
| 
 | |
| 		btScalar denominator= wheel.m_raycastInfo.m_contactNormalWS.dot( wheel.m_raycastInfo.m_wheelDirectionWS );
 | |
| 
 | |
| 		btVector3 chassis_velocity_at_contactPoint;
 | |
| 		btVector3 relpos = wheel.m_raycastInfo.m_contactPointWS-getRigidBody()->getCenterOfMassPosition();
 | |
| 
 | |
| 		chassis_velocity_at_contactPoint = getRigidBody()->getVelocityInLocalPoint(relpos);
 | |
| 
 | |
| 		btScalar projVel = wheel.m_raycastInfo.m_contactNormalWS.dot( chassis_velocity_at_contactPoint );
 | |
| 
 | |
| 		if ( denominator >= btScalar(-0.1))
 | |
| 		{
 | |
| 			wheel.m_suspensionRelativeVelocity = btScalar(0.0);
 | |
| 			wheel.m_clippedInvContactDotSuspension = btScalar(1.0) / btScalar(0.1);
 | |
| 		}
 | |
| 		else
 | |
| 		{
 | |
| 			btScalar inv = btScalar(-1.) / denominator;
 | |
| 			wheel.m_suspensionRelativeVelocity = projVel * inv;
 | |
| 			wheel.m_clippedInvContactDotSuspension = inv;
 | |
| 		}
 | |
| 			
 | |
| 	} else
 | |
| 	{
 | |
| 		//put wheel info as in rest position
 | |
| 		wheel.m_raycastInfo.m_suspensionLength = wheel.getSuspensionRestLength();
 | |
| 		wheel.m_suspensionRelativeVelocity = btScalar(0.0);
 | |
| 		wheel.m_raycastInfo.m_contactNormalWS = - wheel.m_raycastInfo.m_wheelDirectionWS;
 | |
| 		wheel.m_clippedInvContactDotSuspension = btScalar(1.0);
 | |
| 	}
 | |
| 
 | |
| 	return depth;
 | |
| }
 | |
| 
 | |
| 
 | |
| const btTransform& btRaycastVehicle::getChassisWorldTransform() const
 | |
| {
 | |
| 	/*if (getRigidBody()->getMotionState())
 | |
| 	{
 | |
| 		btTransform chassisWorldTrans;
 | |
| 		getRigidBody()->getMotionState()->getWorldTransform(chassisWorldTrans);
 | |
| 		return chassisWorldTrans;
 | |
| 	}
 | |
| 	*/
 | |
| 
 | |
| 	
 | |
| 	return getRigidBody()->getCenterOfMassTransform();
 | |
| }
 | |
| 
 | |
| 
 | |
| void btRaycastVehicle::updateVehicle( btScalar step )
 | |
| {
 | |
| 	{
 | |
| 		for (int i=0;i<getNumWheels();i++)
 | |
| 		{
 | |
| 			updateWheelTransform(i,false);
 | |
| 		}
 | |
| 	}
 | |
| 
 | |
| 
 | |
| 	m_currentVehicleSpeedKmHour = btScalar(3.6) * getRigidBody()->getLinearVelocity().length();
 | |
| 	
 | |
| 	const btTransform& chassisTrans = getChassisWorldTransform();
 | |
| 
 | |
| 	btVector3 forwardW (
 | |
| 		chassisTrans.getBasis()[0][m_indexForwardAxis],
 | |
| 		chassisTrans.getBasis()[1][m_indexForwardAxis],
 | |
| 		chassisTrans.getBasis()[2][m_indexForwardAxis]);
 | |
| 
 | |
| 	if (forwardW.dot(getRigidBody()->getLinearVelocity()) < btScalar(0.))
 | |
| 	{
 | |
| 		m_currentVehicleSpeedKmHour *= btScalar(-1.);
 | |
| 	}
 | |
| 
 | |
| 	//
 | |
| 	// simulate suspension
 | |
| 	//
 | |
| 	
 | |
| 	int i=0;
 | |
| 	for (i=0;i<m_wheelInfo.size();i++)
 | |
| 	{
 | |
| 		//btScalar depth; 
 | |
| 		//depth = 
 | |
| 		rayCast( m_wheelInfo[i]);
 | |
| 	}
 | |
| 
 | |
| 	updateSuspension(step);
 | |
| 
 | |
| 	
 | |
| 	for (i=0;i<m_wheelInfo.size();i++)
 | |
| 	{
 | |
| 		//apply suspension force
 | |
| 		btWheelInfo& wheel = m_wheelInfo[i];
 | |
| 		
 | |
| 		btScalar suspensionForce = wheel.m_wheelsSuspensionForce;
 | |
| 		
 | |
| 		if (suspensionForce > wheel.m_maxSuspensionForce)
 | |
| 		{
 | |
| 			suspensionForce = wheel.m_maxSuspensionForce;
 | |
| 		}
 | |
| 		btVector3 impulse = wheel.m_raycastInfo.m_contactNormalWS * suspensionForce * step;
 | |
| 		btVector3 relpos = wheel.m_raycastInfo.m_contactPointWS - getRigidBody()->getCenterOfMassPosition();
 | |
| 		
 | |
| 		getRigidBody()->applyImpulse(impulse, relpos);
 | |
| 	
 | |
| 	}
 | |
| 	
 | |
| 
 | |
| 	
 | |
| 	updateFriction( step);
 | |
| 
 | |
| 	
 | |
| 	for (i=0;i<m_wheelInfo.size();i++)
 | |
| 	{
 | |
| 		btWheelInfo& wheel = m_wheelInfo[i];
 | |
| 		btVector3 relpos = wheel.m_raycastInfo.m_hardPointWS - getRigidBody()->getCenterOfMassPosition();
 | |
| 		btVector3 vel = getRigidBody()->getVelocityInLocalPoint( relpos );
 | |
| 
 | |
| 		if (wheel.m_raycastInfo.m_isInContact)
 | |
| 		{
 | |
| 			const btTransform&	chassisWorldTransform = getChassisWorldTransform();
 | |
| 
 | |
| 			btVector3 fwd (
 | |
| 				chassisWorldTransform.getBasis()[0][m_indexForwardAxis],
 | |
| 				chassisWorldTransform.getBasis()[1][m_indexForwardAxis],
 | |
| 				chassisWorldTransform.getBasis()[2][m_indexForwardAxis]);
 | |
| 
 | |
| 			btScalar proj = fwd.dot(wheel.m_raycastInfo.m_contactNormalWS);
 | |
| 			fwd -= wheel.m_raycastInfo.m_contactNormalWS * proj;
 | |
| 
 | |
| 			btScalar proj2 = fwd.dot(vel);
 | |
| 			
 | |
| 			wheel.m_deltaRotation = (proj2 * step) / (wheel.m_wheelsRadius);
 | |
| 			wheel.m_rotation += wheel.m_deltaRotation;
 | |
| 
 | |
| 		} else
 | |
| 		{
 | |
| 			wheel.m_rotation += wheel.m_deltaRotation;
 | |
| 		}
 | |
| 		
 | |
| 		wheel.m_deltaRotation *= btScalar(0.99);//damping of rotation when not in contact
 | |
| 
 | |
| 	}
 | |
| 
 | |
| 
 | |
| 
 | |
| }
 | |
| 
 | |
| 
 | |
| void	btRaycastVehicle::setSteeringValue(btScalar steering,int wheel)
 | |
| {
 | |
| 	btAssert(wheel>=0 && wheel < getNumWheels());
 | |
| 
 | |
| 	btWheelInfo& wheelInfo = getWheelInfo(wheel);
 | |
| 	wheelInfo.m_steering = steering;
 | |
| }
 | |
| 
 | |
| 
 | |
| 
 | |
| btScalar	btRaycastVehicle::getSteeringValue(int wheel) const
 | |
| {
 | |
| 	return getWheelInfo(wheel).m_steering;
 | |
| }
 | |
| 
 | |
| 
 | |
| void	btRaycastVehicle::applyEngineForce(btScalar force, int wheel)
 | |
| {
 | |
| 	btAssert(wheel>=0 && wheel < getNumWheels());
 | |
| 	btWheelInfo& wheelInfo = getWheelInfo(wheel);
 | |
| 	wheelInfo.m_engineForce = force;
 | |
| }
 | |
| 
 | |
| 
 | |
| const btWheelInfo&	btRaycastVehicle::getWheelInfo(int index) const
 | |
| {
 | |
| 	btAssert((index >= 0) && (index < 	getNumWheels()));
 | |
| 	
 | |
| 	return m_wheelInfo[index];
 | |
| }
 | |
| 
 | |
| btWheelInfo&	btRaycastVehicle::getWheelInfo(int index) 
 | |
| {
 | |
| 	btAssert((index >= 0) && (index < 	getNumWheels()));
 | |
| 	
 | |
| 	return m_wheelInfo[index];
 | |
| }
 | |
| 
 | |
| void btRaycastVehicle::setBrake(btScalar brake,int wheelIndex)
 | |
| {
 | |
| 	btAssert((wheelIndex >= 0) && (wheelIndex < 	getNumWheels()));
 | |
| 	getWheelInfo(wheelIndex).m_brake = brake;
 | |
| }
 | |
| 
 | |
| 
 | |
| void	btRaycastVehicle::updateSuspension(btScalar deltaTime)
 | |
| {
 | |
| 	(void)deltaTime;
 | |
| 
 | |
| 	btScalar chassisMass = btScalar(1.) / m_chassisBody->getInvMass();
 | |
| 	
 | |
| 	for (int w_it=0; w_it<getNumWheels(); w_it++)
 | |
| 	{
 | |
| 		btWheelInfo &wheel_info = m_wheelInfo[w_it];
 | |
| 		
 | |
| 		if ( wheel_info.m_raycastInfo.m_isInContact )
 | |
| 		{
 | |
| 			btScalar force;
 | |
| 			//	Spring
 | |
| 			{
 | |
| 				btScalar	susp_length			= wheel_info.getSuspensionRestLength();
 | |
| 				btScalar	current_length = wheel_info.m_raycastInfo.m_suspensionLength;
 | |
| 
 | |
| 				btScalar length_diff = (susp_length - current_length);
 | |
| 
 | |
| 				force = wheel_info.m_suspensionStiffness
 | |
| 					* length_diff * wheel_info.m_clippedInvContactDotSuspension;
 | |
| 			}
 | |
| 		
 | |
| 			// Damper
 | |
| 			{
 | |
| 				btScalar projected_rel_vel = wheel_info.m_suspensionRelativeVelocity;
 | |
| 				{
 | |
| 					btScalar	susp_damping;
 | |
| 					if ( projected_rel_vel < btScalar(0.0) )
 | |
| 					{
 | |
| 						susp_damping = wheel_info.m_wheelsDampingCompression;
 | |
| 					}
 | |
| 					else
 | |
| 					{
 | |
| 						susp_damping = wheel_info.m_wheelsDampingRelaxation;
 | |
| 					}
 | |
| 					force -= susp_damping * projected_rel_vel;
 | |
| 				}
 | |
| 			}
 | |
| 
 | |
| 			// RESULT
 | |
| 			wheel_info.m_wheelsSuspensionForce = force * chassisMass;
 | |
| 			if (wheel_info.m_wheelsSuspensionForce < btScalar(0.))
 | |
| 			{
 | |
| 				wheel_info.m_wheelsSuspensionForce = btScalar(0.);
 | |
| 			}
 | |
| 		}
 | |
| 		else
 | |
| 		{
 | |
| 			wheel_info.m_wheelsSuspensionForce = btScalar(0.0);
 | |
| 		}
 | |
| 	}
 | |
| 
 | |
| }
 | |
| 
 | |
| 
 | |
| struct btWheelContactPoint
 | |
| {
 | |
| 	btRigidBody* m_body0;
 | |
| 	btRigidBody* m_body1;
 | |
| 	btVector3	m_frictionPositionWorld;
 | |
| 	btVector3	m_frictionDirectionWorld;
 | |
| 	btScalar	m_jacDiagABInv;
 | |
| 	btScalar	m_maxImpulse;
 | |
| 
 | |
| 
 | |
| 	btWheelContactPoint(btRigidBody* body0,btRigidBody* body1,const btVector3& frictionPosWorld,const btVector3& frictionDirectionWorld, btScalar maxImpulse)
 | |
| 		:m_body0(body0),
 | |
| 		m_body1(body1),
 | |
| 		m_frictionPositionWorld(frictionPosWorld),
 | |
| 		m_frictionDirectionWorld(frictionDirectionWorld),
 | |
| 		m_maxImpulse(maxImpulse)
 | |
| 	{
 | |
| 		btScalar denom0 = body0->computeImpulseDenominator(frictionPosWorld,frictionDirectionWorld);
 | |
| 		btScalar denom1 = body1->computeImpulseDenominator(frictionPosWorld,frictionDirectionWorld);
 | |
| 		btScalar	relaxation = 1.f;
 | |
| 		m_jacDiagABInv = relaxation/(denom0+denom1);
 | |
| 	}
 | |
| 
 | |
| 
 | |
| 
 | |
| };
 | |
| 
 | |
| btScalar calcRollingFriction(btWheelContactPoint& contactPoint);
 | |
| btScalar calcRollingFriction(btWheelContactPoint& contactPoint)
 | |
| {
 | |
| 
 | |
| 	btScalar j1=0.f;
 | |
| 
 | |
| 	const btVector3& contactPosWorld = contactPoint.m_frictionPositionWorld;
 | |
| 
 | |
| 	btVector3 rel_pos1 = contactPosWorld - contactPoint.m_body0->getCenterOfMassPosition(); 
 | |
| 	btVector3 rel_pos2 = contactPosWorld - contactPoint.m_body1->getCenterOfMassPosition();
 | |
| 	
 | |
| 	btScalar maxImpulse  = contactPoint.m_maxImpulse;
 | |
| 	
 | |
| 	btVector3 vel1 = contactPoint.m_body0->getVelocityInLocalPoint(rel_pos1);
 | |
| 	btVector3 vel2 = contactPoint.m_body1->getVelocityInLocalPoint(rel_pos2);
 | |
| 	btVector3 vel = vel1 - vel2;
 | |
| 
 | |
| 	btScalar vrel = contactPoint.m_frictionDirectionWorld.dot(vel);
 | |
| 
 | |
| 	// calculate j that moves us to zero relative velocity
 | |
| 	j1 = -vrel * contactPoint.m_jacDiagABInv;
 | |
| 	btSetMin(j1, maxImpulse);
 | |
| 	btSetMax(j1, -maxImpulse);
 | |
| 
 | |
| 	return j1;
 | |
| }
 | |
| 
 | |
| 
 | |
| 
 | |
| 
 | |
| btScalar sideFrictionStiffness2 = btScalar(1.0);
 | |
| void	btRaycastVehicle::updateFriction(btScalar	timeStep)
 | |
| {
 | |
| 
 | |
| 		//calculate the impulse, so that the wheels don't move sidewards
 | |
| 		int numWheel = getNumWheels();
 | |
| 		if (!numWheel)
 | |
| 			return;
 | |
| 
 | |
| 		m_forwardWS.resize(numWheel);
 | |
| 		m_axle.resize(numWheel);
 | |
| 		m_forwardImpulse.resize(numWheel);
 | |
| 		m_sideImpulse.resize(numWheel);
 | |
| 		
 | |
| 		int numWheelsOnGround = 0;
 | |
| 	
 | |
| 
 | |
| 		//collapse all those loops into one!
 | |
| 		for (int i=0;i<getNumWheels();i++)
 | |
| 		{
 | |
| 			btWheelInfo& wheelInfo = m_wheelInfo[i];
 | |
| 			class btRigidBody* groundObject = (class btRigidBody*) wheelInfo.m_raycastInfo.m_groundObject;
 | |
| 			if (groundObject)
 | |
| 				numWheelsOnGround++;
 | |
| 			m_sideImpulse[i] = btScalar(0.);
 | |
| 			m_forwardImpulse[i] = btScalar(0.);
 | |
| 
 | |
| 		}
 | |
| 	
 | |
| 		{
 | |
| 	
 | |
| 			for (int i=0;i<getNumWheels();i++)
 | |
| 			{
 | |
| 
 | |
| 				btWheelInfo& wheelInfo = m_wheelInfo[i];
 | |
| 					
 | |
| 				class btRigidBody* groundObject = (class btRigidBody*) wheelInfo.m_raycastInfo.m_groundObject;
 | |
| 
 | |
| 				if (groundObject)
 | |
| 				{
 | |
| 
 | |
| 					const btTransform& wheelTrans = getWheelTransformWS( i );
 | |
| 
 | |
| 					btMatrix3x3 wheelBasis0 = wheelTrans.getBasis();
 | |
| 					m_axle[i] = btVector3(	
 | |
| 						wheelBasis0[0][m_indexRightAxis],
 | |
| 						wheelBasis0[1][m_indexRightAxis],
 | |
| 						wheelBasis0[2][m_indexRightAxis]);
 | |
| 					
 | |
| 					const btVector3& surfNormalWS = wheelInfo.m_raycastInfo.m_contactNormalWS;
 | |
| 					btScalar proj = m_axle[i].dot(surfNormalWS);
 | |
| 					m_axle[i] -= surfNormalWS * proj;
 | |
| 					m_axle[i] = m_axle[i].normalize();
 | |
| 					
 | |
| 					m_forwardWS[i] = surfNormalWS.cross(m_axle[i]);
 | |
| 					m_forwardWS[i].normalize();
 | |
| 
 | |
| 				
 | |
| 					resolveSingleBilateral(*m_chassisBody, wheelInfo.m_raycastInfo.m_contactPointWS,
 | |
| 							  *groundObject, wheelInfo.m_raycastInfo.m_contactPointWS,
 | |
| 							  btScalar(0.), m_axle[i],m_sideImpulse[i],timeStep);
 | |
| 
 | |
| 					m_sideImpulse[i] *= sideFrictionStiffness2;
 | |
| 						
 | |
| 				}
 | |
| 				
 | |
| 
 | |
| 			}
 | |
| 		}
 | |
| 
 | |
| 	btScalar sideFactor = btScalar(1.);
 | |
| 	btScalar fwdFactor = 0.5;
 | |
| 
 | |
| 	bool sliding = false;
 | |
| 	{
 | |
| 		for (int wheel =0;wheel <getNumWheels();wheel++)
 | |
| 		{
 | |
| 			btWheelInfo& wheelInfo = m_wheelInfo[wheel];
 | |
| 			class btRigidBody* groundObject = (class btRigidBody*) wheelInfo.m_raycastInfo.m_groundObject;
 | |
| 
 | |
| 			btScalar	rollingFriction = 0.f;
 | |
| 
 | |
| 			if (groundObject)
 | |
| 			{
 | |
| 				if (wheelInfo.m_engineForce != 0.f)
 | |
| 				{
 | |
| 					rollingFriction = wheelInfo.m_engineForce* timeStep;
 | |
| 				} else
 | |
| 				{
 | |
| 					btScalar defaultRollingFrictionImpulse = 0.f;
 | |
| 					btScalar maxImpulse = wheelInfo.m_brake ? wheelInfo.m_brake : defaultRollingFrictionImpulse;
 | |
| 					btWheelContactPoint contactPt(m_chassisBody,groundObject,wheelInfo.m_raycastInfo.m_contactPointWS,m_forwardWS[wheel],maxImpulse);
 | |
| 					rollingFriction = calcRollingFriction(contactPt);
 | |
| 				}
 | |
| 			}
 | |
| 
 | |
| 			//switch between active rolling (throttle), braking and non-active rolling friction (no throttle/break)
 | |
| 			
 | |
| 
 | |
| 
 | |
| 
 | |
| 			m_forwardImpulse[wheel] = btScalar(0.);
 | |
| 			m_wheelInfo[wheel].m_skidInfo= btScalar(1.);
 | |
| 
 | |
| 			if (groundObject)
 | |
| 			{
 | |
| 				m_wheelInfo[wheel].m_skidInfo= btScalar(1.);
 | |
| 				
 | |
| 				btScalar maximp = wheelInfo.m_wheelsSuspensionForce * timeStep * wheelInfo.m_frictionSlip;
 | |
| 				btScalar maximpSide = maximp;
 | |
| 
 | |
| 				btScalar maximpSquared = maximp * maximpSide;
 | |
| 			
 | |
| 
 | |
| 				m_forwardImpulse[wheel] = rollingFriction;//wheelInfo.m_engineForce* timeStep;
 | |
| 
 | |
| 				btScalar x = (m_forwardImpulse[wheel] ) * fwdFactor;
 | |
| 				btScalar y = (m_sideImpulse[wheel] ) * sideFactor;
 | |
| 				
 | |
| 				btScalar impulseSquared = (x*x + y*y);
 | |
| 
 | |
| 				if (impulseSquared > maximpSquared)
 | |
| 				{
 | |
| 					sliding = true;
 | |
| 					
 | |
| 					btScalar factor = maximp / btSqrt(impulseSquared);
 | |
| 					
 | |
| 					m_wheelInfo[wheel].m_skidInfo *= factor;
 | |
| 				}
 | |
| 			} 
 | |
| 
 | |
| 		}
 | |
| 	}
 | |
| 
 | |
| 	
 | |
| 
 | |
| 
 | |
| 		if (sliding)
 | |
| 		{
 | |
| 			for (int wheel = 0;wheel < getNumWheels(); wheel++)
 | |
| 			{
 | |
| 				if (m_sideImpulse[wheel] != btScalar(0.))
 | |
| 				{
 | |
| 					if (m_wheelInfo[wheel].m_skidInfo< btScalar(1.))
 | |
| 					{
 | |
| 						m_forwardImpulse[wheel] *=	m_wheelInfo[wheel].m_skidInfo;
 | |
| 						m_sideImpulse[wheel] *= m_wheelInfo[wheel].m_skidInfo;
 | |
| 					}
 | |
| 				}
 | |
| 			}
 | |
| 		}
 | |
| 
 | |
| 		// apply the impulses
 | |
| 		{
 | |
| 			for (int wheel = 0;wheel<getNumWheels() ; wheel++)
 | |
| 			{
 | |
| 				btWheelInfo& wheelInfo = m_wheelInfo[wheel];
 | |
| 
 | |
| 				btVector3 rel_pos = wheelInfo.m_raycastInfo.m_contactPointWS - 
 | |
| 						m_chassisBody->getCenterOfMassPosition();
 | |
| 
 | |
| 				if (m_forwardImpulse[wheel] != btScalar(0.))
 | |
| 				{
 | |
| 					m_chassisBody->applyImpulse(m_forwardWS[wheel]*(m_forwardImpulse[wheel]),rel_pos);
 | |
| 				}
 | |
| 				if (m_sideImpulse[wheel] != btScalar(0.))
 | |
| 				{
 | |
| 					class btRigidBody* groundObject = (class btRigidBody*) m_wheelInfo[wheel].m_raycastInfo.m_groundObject;
 | |
| 
 | |
| 					btVector3 rel_pos2 = wheelInfo.m_raycastInfo.m_contactPointWS - 
 | |
| 						groundObject->getCenterOfMassPosition();
 | |
| 
 | |
| 					
 | |
| 					btVector3 sideImp = m_axle[wheel] * m_sideImpulse[wheel];
 | |
| 
 | |
| #if defined ROLLING_INFLUENCE_FIX // fix. It only worked if car's up was along Y - VT.
 | |
| 					btVector3 vChassisWorldUp = getRigidBody()->getCenterOfMassTransform().getBasis().getColumn(m_indexUpAxis);
 | |
| 					rel_pos -= vChassisWorldUp * (vChassisWorldUp.dot(rel_pos) * (1.f-wheelInfo.m_rollInfluence));
 | |
| #else
 | |
| 					rel_pos[m_indexUpAxis] *= wheelInfo.m_rollInfluence;
 | |
| #endif
 | |
| 					m_chassisBody->applyImpulse(sideImp,rel_pos);
 | |
| 
 | |
| 					//apply friction impulse on the ground
 | |
| 					groundObject->applyImpulse(-sideImp,rel_pos2);
 | |
| 				}
 | |
| 			}
 | |
| 		}
 | |
| 
 | |
| 	
 | |
| }
 | |
| 
 | |
| 
 | |
| 
 | |
| void	btRaycastVehicle::debugDraw(btIDebugDraw* debugDrawer)
 | |
| {
 | |
| 
 | |
| 	for (int v=0;v<this->getNumWheels();v++)
 | |
| 	{
 | |
| 		btVector3 wheelColor(0,1,1);
 | |
| 		if (getWheelInfo(v).m_raycastInfo.m_isInContact)
 | |
| 		{
 | |
| 			wheelColor.setValue(0,0,1);
 | |
| 		} else
 | |
| 		{
 | |
| 			wheelColor.setValue(1,0,1);
 | |
| 		}
 | |
| 
 | |
| 		btVector3 wheelPosWS = getWheelInfo(v).m_worldTransform.getOrigin();
 | |
| 
 | |
| 		btVector3 axle = btVector3(	
 | |
| 			getWheelInfo(v).m_worldTransform.getBasis()[0][getRightAxis()],
 | |
| 			getWheelInfo(v).m_worldTransform.getBasis()[1][getRightAxis()],
 | |
| 			getWheelInfo(v).m_worldTransform.getBasis()[2][getRightAxis()]);
 | |
| 
 | |
| 		//debug wheels (cylinders)
 | |
| 		debugDrawer->drawLine(wheelPosWS,wheelPosWS+axle,wheelColor);
 | |
| 		debugDrawer->drawLine(wheelPosWS,getWheelInfo(v).m_raycastInfo.m_contactPointWS,wheelColor);
 | |
| 
 | |
| 	}
 | |
| }
 | |
| 
 | |
| 
 | |
| void* btDefaultVehicleRaycaster::castRay(const btVector3& from,const btVector3& to, btVehicleRaycasterResult& result)
 | |
| {
 | |
| //	RayResultCallback& resultCallback;
 | |
| 
 | |
| 	btCollisionWorld::ClosestRayResultCallback rayCallback(from,to);
 | |
| 
 | |
| 	m_dynamicsWorld->rayTest(from, to, rayCallback);
 | |
| 
 | |
| 	if (rayCallback.hasHit())
 | |
| 	{
 | |
| 		
 | |
| 		const btRigidBody* body = btRigidBody::upcast(rayCallback.m_collisionObject);
 | |
|         if (body && body->hasContactResponse())
 | |
| 		{
 | |
| 			result.m_hitPointInWorld = rayCallback.m_hitPointWorld;
 | |
| 			result.m_hitNormalInWorld = rayCallback.m_hitNormalWorld;
 | |
| 			result.m_hitNormalInWorld.normalize();
 | |
| 			result.m_distFraction = rayCallback.m_closestHitFraction;
 | |
| 			return (void*)body;
 | |
| 		}
 | |
| 	}
 | |
| 	return 0;
 | |
| }
 | |
| 
 |