bullet3/examples/Tutorial/Tutorial.cpp

#include "Tutorial.h"
#include "../CommonInterfaces/CommonGraphicsAppInterface.h"
#include "../CommonInterfaces/CommonRenderInterface.h"

#include "../CommonInterfaces/CommonExampleInterface.h"
#include "LinearMath/btTransform.h"

#include "../CommonInterfaces/CommonGUIHelperInterface.h"
#include "../RenderingExamples/TimeSeriesCanvas.h"
#include "stb_image/stb_image.h"
#include "Bullet3Common/b3Quaternion.h"
#include "Bullet3Common/b3Matrix3x3.h"
#include "../CommonInterfaces/CommonParameterInterface.h"

#include "LinearMath/btAlignedObjectArray.h"
#define stdvector btAlignedObjectArray

#define SPHERE_RADIUS 1
static btScalar gRestitution = 0.f;
static btScalar gMassA = 1.f;
static btScalar gMassB = 0.f;

enum LWEnumCollisionTypes
{
	LW_PLANE_TYPE,
	LW_SPHERE_TYPE,
	LW_BOX_TYPE
};

struct LWPlane
{
	BT_DECLARE_ALIGNED_ALLOCATOR();

	b3Vector3 m_normal;
	btScalar m_planeConstant;
};

struct LWSphere
{
	btScalar m_radius;

	void computeLocalInertia(b3Scalar mass, b3Vector3& localInertia)
	{
		btScalar elem = b3Scalar(0.4) * mass * m_radius * m_radius;
		localInertia.setValue(elem, elem, elem);
	}
};

struct LWBox
{
	BT_DECLARE_ALIGNED_ALLOCATOR();
	b3Vector3 m_halfExtents;
};

struct LWCollisionShape
{
	LWEnumCollisionTypes m_type;
	union {
		LWPlane m_plane;
		LWSphere m_sphere;
		LWBox m_box;
	};
};

struct LWPose
{
	BT_DECLARE_ALIGNED_ALLOCATOR();

	b3Vector3 m_position;
	b3Quaternion m_orientation;
	LWPose()
		: m_position(b3MakeVector3(0, 0, 0)),
		  m_orientation(0, 0, 0, 1)
	{
	}

	b3Vector3 transformPoint(const b3Vector3& pointIn)
	{
		b3Vector3 rotPoint = b3QuatRotate(m_orientation, pointIn);
		return rotPoint + m_position;
	}
};
struct LWContactPoint
{
	b3Vector3 m_ptOnAWorld;
	b3Vector3 m_ptOnBWorld;
	b3Vector3 m_normalOnB;
	btScalar m_distance;
};

///returns true if we found a pair of closest points
void ComputeClosestPointsPlaneSphere(const LWPlane& planeWorld, const LWSphere& sphere, const LWPose& spherePose, LWContactPoint& pointOut)
{
	b3Vector3 spherePosWorld = spherePose.m_position;
	btScalar t = -(spherePosWorld.dot(-planeWorld.m_normal) + planeWorld.m_planeConstant);
	b3Vector3 intersectionPoint = spherePosWorld + t * -planeWorld.m_normal;
	b3Scalar distance = t - sphere.m_radius;
	pointOut.m_distance = distance;
	pointOut.m_ptOnBWorld = intersectionPoint;
	pointOut.m_ptOnAWorld = spherePosWorld + sphere.m_radius * -planeWorld.m_normal;
	pointOut.m_normalOnB = planeWorld.m_normal;
}

void ComputeClosestPointsSphereSphere(const LWSphere& sphereA, const LWPose& sphereAPose, const LWSphere& sphereB, const LWPose& sphereBPose, LWContactPoint& pointOut)
{
	b3Vector3 diff = sphereAPose.m_position - sphereBPose.m_position;
	btScalar len = diff.length();
	pointOut.m_distance = len - (sphereA.m_radius + sphereB.m_radius);
	pointOut.m_normalOnB = b3MakeVector3(1, 0, 0);
	if (len > B3_EPSILON)
	{
		pointOut.m_normalOnB = diff / len;
	}
	pointOut.m_ptOnAWorld = sphereAPose.m_position - sphereA.m_radius * pointOut.m_normalOnB;
	pointOut.m_ptOnBWorld = pointOut.m_ptOnAWorld - pointOut.m_normalOnB * pointOut.m_distance;
}

enum LWRIGIDBODY_FLAGS
{
	LWFLAG_USE_QUATERNION_DERIVATIVE = 1,

};
struct LWRigidBody
{
	BT_DECLARE_ALIGNED_ALLOCATOR();

	LWPose m_worldPose;
	b3Vector3 m_linearVelocity;
	b3Vector3 m_angularVelocity;
	b3Vector3 m_gravityAcceleration;
	b3Vector3 m_localInertia;
	b3Scalar m_invMass;

	b3Matrix3x3 m_invInertiaTensorWorld;

	void computeInvInertiaTensorWorld()
	{
		b3Vector3 invInertiaLocal;
		invInertiaLocal.setValue(m_localInertia.x != btScalar(0.0) ? btScalar(1.0) / m_localInertia.x : btScalar(0.0),
								 m_localInertia.y != btScalar(0.0) ? btScalar(1.0) / m_localInertia.y : btScalar(0.0),
								 m_localInertia.z != btScalar(0.0) ? btScalar(1.0) / m_localInertia.z : btScalar(0.0));
		b3Matrix3x3 m(m_worldPose.m_orientation);
		m_invInertiaTensorWorld = m.scaled(invInertiaLocal) * m.transpose();
	}

	int m_graphicsIndex;
	LWCollisionShape m_collisionShape;

	LWRIGIDBODY_FLAGS m_flags;

	LWRigidBody()
		: m_linearVelocity(b3MakeVector3(0, 0, 0)),
		  m_angularVelocity(b3MakeVector3(0, 0, 0)),
		  m_gravityAcceleration(b3MakeVector3(0, 0, 0)),  //-10,0)),
		  m_flags(LWFLAG_USE_QUATERNION_DERIVATIVE)
	{
	}

	const b3Vector3& getPosition() const
	{
		return m_worldPose.m_position;
	}

	b3Vector3 getVelocity(const b3Vector3& relPos) const
	{
		return m_linearVelocity + m_angularVelocity.cross(relPos);
	}

	void integrateAcceleration(double deltaTime)
	{
		m_linearVelocity += m_gravityAcceleration * deltaTime;
	}

	void applyImpulse(const b3Vector3& impulse, const b3Vector3& rel_pos)
	{
		m_linearVelocity += impulse * m_invMass;
		b3Vector3 torqueImpulse = rel_pos.cross(impulse);
		m_angularVelocity += m_invInertiaTensorWorld * torqueImpulse;
	}

	void integrateVelocity(double deltaTime)
	{
		LWPose newPose;

		newPose.m_position = m_worldPose.m_position + m_linearVelocity * deltaTime;

		if (m_flags & LWFLAG_USE_QUATERNION_DERIVATIVE)
		{
			newPose.m_orientation = m_worldPose.m_orientation;
			newPose.m_orientation += (m_angularVelocity * newPose.m_orientation) * (deltaTime * btScalar(0.5));
			newPose.m_orientation.normalize();
			m_worldPose = newPose;
		}
		else
		{
			//Exponential map
			//google for "Practical Parameterization of Rotations Using the Exponential Map", F. Sebastian Grassia

			//btQuaternion q_w = [ sin(|w|*dt/2) * w/|w| , cos(|w|*dt/2)]
			//btQuaternion q_new =  q_w * q_old;

			b3Vector3 axis;
			b3Scalar fAngle = m_angularVelocity.length();
			//limit the angular motion
			const btScalar angularMotionThreshold = btScalar(0.5) * SIMD_HALF_PI;

			if (fAngle * deltaTime > angularMotionThreshold)
			{
				fAngle = angularMotionThreshold / deltaTime;
			}

			if (fAngle < btScalar(0.001))
			{
				// use Taylor's expansions of sync function
				axis = m_angularVelocity * (btScalar(0.5) * deltaTime - (deltaTime * deltaTime * deltaTime) * (btScalar(0.020833333333)) * fAngle * fAngle);
			}
			else
			{
				// sync(fAngle) = sin(c*fAngle)/t
				axis = m_angularVelocity * (btSin(btScalar(0.5) * fAngle * deltaTime) / fAngle);
			}
			b3Quaternion dorn(axis.x, axis.y, axis.z, btCos(fAngle * deltaTime * b3Scalar(0.5)));
			b3Quaternion orn0 = m_worldPose.m_orientation;

			b3Quaternion predictedOrn = dorn * orn0;
			predictedOrn.normalize();
			m_worldPose.m_orientation = predictedOrn;
		}
	}

	void stepSimulation(double deltaTime)
	{
		integrateVelocity(deltaTime);
	}
};

b3Scalar resolveCollision(LWRigidBody& bodyA,
						  LWRigidBody& bodyB,
						  LWContactPoint& contactPoint)
{
	b3Assert(contactPoint.m_distance <= 0);

	btScalar appliedImpulse = 0.f;

	b3Vector3 rel_pos1 = contactPoint.m_ptOnAWorld - bodyA.m_worldPose.m_position;
	b3Vector3 rel_pos2 = contactPoint.m_ptOnBWorld - bodyB.getPosition();

	btScalar rel_vel = contactPoint.m_normalOnB.dot(bodyA.getVelocity(rel_pos1) - bodyB.getVelocity(rel_pos2));
	if (rel_vel < -B3_EPSILON)
	{
		b3Vector3 temp1 = bodyA.m_invInertiaTensorWorld * rel_pos1.cross(contactPoint.m_normalOnB);
		b3Vector3 temp2 = bodyB.m_invInertiaTensorWorld * rel_pos2.cross(contactPoint.m_normalOnB);

		btScalar impulse = -(1.0f + gRestitution) * rel_vel /
						   (bodyA.m_invMass + bodyB.m_invMass + contactPoint.m_normalOnB.dot(temp1.cross(rel_pos1) + temp2.cross(rel_pos2)));

		b3Vector3 impulse_vector = contactPoint.m_normalOnB * impulse;
		b3Printf("impulse = %f\n", impulse);
		appliedImpulse = impulse;
		bodyA.applyImpulse(impulse_vector, rel_pos1);
		bodyB.applyImpulse(-impulse_vector, rel_pos2);
	}
	return appliedImpulse;
}

class Tutorial : public CommonExampleInterface
{
	CommonGraphicsApp* m_app;
	GUIHelperInterface* m_guiHelper;
	int m_tutorialIndex;

	stdvector<LWRigidBody*> m_bodies;

	TimeSeriesCanvas* m_timeSeriesCanvas0;
	TimeSeriesCanvas* m_timeSeriesCanvas1;

	stdvector<LWContactPoint> m_contactPoints;

	int m_stage;
	int m_counter;

public:
	Tutorial(GUIHelperInterface* guiHelper, int tutorialIndex)
		: m_app(guiHelper->getAppInterface()),
		  m_guiHelper(guiHelper),
		  m_tutorialIndex(tutorialIndex),
		  m_timeSeriesCanvas0(0),
		  m_timeSeriesCanvas1(0),
		  m_stage(0),
		  m_counter(0)
	{
		int numBodies = 1;

		m_app->setUpAxis(1);

		switch (m_tutorialIndex)
		{
			case TUT_VELOCITY:
			{
				numBodies = 10;
				m_timeSeriesCanvas0 = new TimeSeriesCanvas(m_app->m_2dCanvasInterface, 512, 256, "Constant Velocity");

				m_timeSeriesCanvas0->setupTimeSeries(2, 60, 0);
				m_timeSeriesCanvas0->addDataSource("X position (m)", 255, 0, 0);
				m_timeSeriesCanvas0->addDataSource("X velocity (m/s)", 0, 0, 255);
				m_timeSeriesCanvas0->addDataSource("dX/dt (m/s)", 0, 0, 0);
				break;
			}
			case TUT_ACCELERATION:
			{
				numBodies = 10;
				m_timeSeriesCanvas1 = new TimeSeriesCanvas(m_app->m_2dCanvasInterface, 256, 512, "Constant Acceleration");

				m_timeSeriesCanvas1->setupTimeSeries(50, 60, 0);
				m_timeSeriesCanvas1->addDataSource("Y position (m)", 255, 0, 0);
				m_timeSeriesCanvas1->addDataSource("Y velocity (m/s)", 0, 0, 255);
				m_timeSeriesCanvas1->addDataSource("dY/dt (m/s)", 0, 0, 0);
				break;
			}
			case TUT_COLLISION:
			{
				numBodies = 2;
				m_timeSeriesCanvas1 = new TimeSeriesCanvas(m_app->m_2dCanvasInterface, 512, 200, "Distance");
				m_timeSeriesCanvas1->setupTimeSeries(1.5, 60, 0);
				m_timeSeriesCanvas1->addDataSource("distance", 255, 0, 0);
				break;
			}

			case TUT_SOLVE_CONTACT_CONSTRAINT:
			{
				numBodies = 2;
				m_timeSeriesCanvas1 = new TimeSeriesCanvas(m_app->m_2dCanvasInterface, 512, 200, "Collision Impulse");
				m_timeSeriesCanvas1->setupTimeSeries(1.5, 60, 0);
				m_timeSeriesCanvas1->addDataSource("Distance", 0, 0, 255);
				m_timeSeriesCanvas1->addDataSource("Impulse magnutide", 255, 0, 0);

				{
					SliderParams slider("Restitution", &gRestitution);
					slider.m_minVal = 0;
					slider.m_maxVal = 1;
					m_guiHelper->getParameterInterface()->registerSliderFloatParameter(slider);
				}
				{
					SliderParams slider("Mass A", &gMassA);
					slider.m_minVal = 0;
					slider.m_maxVal = 100;
					m_guiHelper->getParameterInterface()->registerSliderFloatParameter(slider);
				}

				{
					SliderParams slider("Mass B", &gMassB);
					slider.m_minVal = 0;
					slider.m_maxVal = 100;
					m_guiHelper->getParameterInterface()->registerSliderFloatParameter(slider);
				}

				break;
			}

			default:
			{
				m_timeSeriesCanvas0 = new TimeSeriesCanvas(m_app->m_2dCanvasInterface, 512, 256, "Unknown");
				m_timeSeriesCanvas0->setupTimeSeries(1, 60, 0);
			}
		};

		if (m_tutorialIndex == TUT_VELOCITY)
		{
			int boxId = m_app->registerCubeShape(100, 1, 100);
			b3Vector3 pos = b3MakeVector3(0, -3.5, 0);
			b3Quaternion orn(0, 0, 0, 1);
			b3Vector4 color = b3MakeVector4(1, 1, 1, 1);
			b3Vector3 scaling = b3MakeVector3(1, 1, 1);
			m_app->m_renderer->registerGraphicsInstance(boxId, pos, orn, color, scaling);
		}

		for (int i = 0; i < numBodies; i++)
		{
			m_bodies.push_back(new LWRigidBody());
		}
		for (int i = 0; i < m_bodies.size(); i++)
		{
			m_bodies[i]->m_worldPose.m_position.setValue((i / 4) * 5, 3, (i & 3) * 5);
		}
		{
			int textureIndex = -1;

			if (1)
			{
				int width, height, n;

				const char* filename = "data/checker_huge.gif";
				const unsigned char* image = 0;

				const char* prefix[] = {"./", "../", "../../", "../../../", "../../../../"};
				int numprefix = sizeof(prefix) / sizeof(const char*);

				for (int i = 0; !image && i < numprefix; i++)
				{
					char relativeFileName[1024];
					sprintf(relativeFileName, "%s%s", prefix[i], filename);
					image = stbi_load(relativeFileName, &width, &height, &n, 3);
				}

				b3Assert(image);
				if (image)
				{
					textureIndex = m_app->m_renderer->registerTexture(image, width, height);
				}
			}

			//            int boxId = m_app->registerCubeShape(1,1,1,textureIndex);
			int sphereTransparent = m_app->registerGraphicsUnitSphereShape(SPHERE_LOD_HIGH, textureIndex);
			int sphereOpaque = m_app->registerGraphicsUnitSphereShape(SPHERE_LOD_HIGH, textureIndex);

			b3Vector3 scaling = b3MakeVector3(SPHERE_RADIUS, SPHERE_RADIUS, SPHERE_RADIUS);
			for (int i = 0; i < m_bodies.size(); i++)
			{
				int gfxShape = sphereOpaque;
				b3Vector4 color = b3MakeVector4(.1, .1, 1, 1);
				if (i % 2)
				{
					color.setValue(1, .1, .1, 0.1);
					gfxShape = sphereTransparent;
				}
				m_bodies[i]->m_collisionShape.m_sphere.m_radius = SPHERE_RADIUS;
				m_bodies[i]->m_collisionShape.m_type = LW_SPHERE_TYPE;

				m_bodies[i]->m_graphicsIndex = m_app->m_renderer->registerGraphicsInstance(gfxShape, m_bodies[i]->m_worldPose.m_position, m_bodies[i]->m_worldPose.m_orientation, color, scaling);
				m_app->m_renderer->writeSingleInstanceTransformToCPU(m_bodies[i]->m_worldPose.m_position, m_bodies[i]->m_worldPose.m_orientation, m_bodies[i]->m_graphicsIndex);
			}
		}

		if (m_tutorialIndex == TUT_SOLVE_CONTACT_CONSTRAINT)
		{
			m_bodies[0]->m_invMass = gMassA ? 1. / gMassA : 0;
			m_bodies[0]->m_collisionShape.m_sphere.computeLocalInertia(gMassA, m_bodies[0]->m_localInertia);

			m_bodies[1]->m_invMass = gMassB ? 1. / gMassB : 0;
			m_bodies[1]->m_collisionShape.m_sphere.computeLocalInertia(gMassB, m_bodies[1]->m_localInertia);

			if (gMassA)
				m_bodies[0]->m_linearVelocity.setValue(0, 0, 1);
			if (gMassB)
				m_bodies[1]->m_linearVelocity.setValue(0, 0, -1);
		}

		m_app->m_renderer->writeTransforms();
	}
	virtual ~Tutorial()
	{
		delete m_timeSeriesCanvas0;
		delete m_timeSeriesCanvas1;

		m_timeSeriesCanvas0 = 0;
		m_timeSeriesCanvas1 = 0;
	}

	virtual void initPhysics()
	{
	}
	virtual void exitPhysics()
	{
	}

	void tutorial1Update(float deltaTime);
	void tutorial2Update(float deltaTime);
	void tutorialCollisionUpdate(float deltaTime, LWContactPoint& contact);
	void tutorialSolveContactConstraintUpdate(float deltaTime, LWContactPoint& contact);

	virtual void stepSimulation(float deltaTime)
	{
		switch (m_tutorialIndex)
		{
			case TUT_VELOCITY:
			{
				tutorial1Update(deltaTime);
				float xPos = m_bodies[0]->m_worldPose.m_position.x;
				float xVel = m_bodies[0]->m_linearVelocity.x;
				m_timeSeriesCanvas0->insertDataAtCurrentTime(xPos, 0, true);
				m_timeSeriesCanvas0->insertDataAtCurrentTime(xVel, 1, true);
				break;
			}
			case TUT_ACCELERATION:
			{
				tutorial2Update(deltaTime);
				float yPos = m_bodies[0]->m_worldPose.m_position.y;
				float yVel = m_bodies[0]->m_linearVelocity.y;
				m_timeSeriesCanvas1->insertDataAtCurrentTime(yPos, 0, true);
				m_timeSeriesCanvas1->insertDataAtCurrentTime(yVel, 1, true);

				break;
			}
			case TUT_COLLISION:
			{
				m_contactPoints.clear();
				LWContactPoint contactPoint;
				tutorialCollisionUpdate(deltaTime, contactPoint);
				m_contactPoints.push_back(contactPoint);
				m_timeSeriesCanvas1->insertDataAtCurrentTime(contactPoint.m_distance, 0, true);

				break;
			}
			case TUT_SOLVE_CONTACT_CONSTRAINT:
			{
				m_contactPoints.clear();
				LWContactPoint contactPoint;
				tutorialSolveContactConstraintUpdate(deltaTime, contactPoint);
				m_contactPoints.push_back(contactPoint);
				if (contactPoint.m_distance < 0)
				{
					m_bodies[0]->computeInvInertiaTensorWorld();
					m_bodies[1]->computeInvInertiaTensorWorld();

					b3Scalar appliedImpulse = resolveCollision(*m_bodies[0],
															   *m_bodies[1],
															   contactPoint);

					m_timeSeriesCanvas1->insertDataAtCurrentTime(appliedImpulse, 1, true);
				}
				else
				{
					m_timeSeriesCanvas1->insertDataAtCurrentTime(0., 1, true);
				}
				m_timeSeriesCanvas1->insertDataAtCurrentTime(contactPoint.m_distance, 0, true);

				break;
			}

			default:
			{
			}
		};

		if (m_timeSeriesCanvas0)
			m_timeSeriesCanvas0->nextTick();

		if (m_timeSeriesCanvas1)
			m_timeSeriesCanvas1->nextTick();

		for (int i = 0; i < m_bodies.size(); i++)
		{
			m_bodies[i]->integrateAcceleration(deltaTime);
			m_bodies[i]->integrateVelocity(deltaTime);

			m_app->m_renderer->writeSingleInstanceTransformToCPU(m_bodies[i]->m_worldPose.m_position, m_bodies[i]->m_worldPose.m_orientation, m_bodies[i]->m_graphicsIndex);
		}

		m_app->m_renderer->writeTransforms();
	}
	virtual void renderScene()
	{
		m_app->m_renderer->renderScene();
		m_app->drawText3D("X", 1, 0, 0, 1);
		m_app->drawText3D("Y", 0, 1, 0, 1);
		m_app->drawText3D("Z", 0, 0, 1, 1);

		for (int i = 0; i < m_contactPoints.size(); i++)
		{
			const LWContactPoint& contact = m_contactPoints[i];
			b3Vector3 color = b3MakeVector3(1, 1, 0);
			float lineWidth = 3;
			if (contact.m_distance < 0)
			{
				color.setValue(1, 0, 0);
			}
			m_app->m_renderer->drawLine(contact.m_ptOnAWorld, contact.m_ptOnBWorld, color, lineWidth);
		}
	}

	virtual void physicsDebugDraw(int debugDrawFlags)
	{
	}
	virtual bool mouseMoveCallback(float x, float y)
	{
		return false;
	}
	virtual bool mouseButtonCallback(int button, int state, float x, float y)
	{
		return false;
	}
	virtual bool keyboardCallback(int key, int state)
	{
		return false;
	}

	virtual void resetCamera()
	{
		float dist = 10.5;
		float pitch = -32;
		float yaw = 136;
		float targetPos[3] = {0, 0, 0};
		if (m_app->m_renderer && m_app->m_renderer->getActiveCamera())
		{
			m_app->m_renderer->getActiveCamera()->setCameraDistance(dist);
			m_app->m_renderer->getActiveCamera()->setCameraPitch(pitch);
			m_app->m_renderer->getActiveCamera()->setCameraYaw(yaw);
			m_app->m_renderer->getActiveCamera()->setCameraTargetPosition(targetPos[0], targetPos[1], targetPos[2]);
		}
	}
};

void Tutorial::tutorial2Update(float deltaTime)
{
	for (int i = 0; i < m_bodies.size(); i++)
	{
		m_bodies[i]->m_gravityAcceleration.setValue(0, -10, 0);
	}
}
void Tutorial::tutorial1Update(float deltaTime)
{
	for (int i = 0; i < m_bodies.size(); i++)
	{
		switch (m_stage)
		{
			case 0:
			{
				m_bodies[i]->m_angularVelocity = b3MakeVector3(0, 0, 0);
				m_bodies[i]->m_linearVelocity = b3MakeVector3(1, 0, 0);
				break;
			}
			case 1:
			{
				m_bodies[i]->m_linearVelocity = b3MakeVector3(-1, 0, 0);
				break;
			}
			case 2:
			{
				m_bodies[i]->m_linearVelocity = b3MakeVector3(0, 1, 0);
				break;
			}
			case 3:
			{
				m_bodies[i]->m_linearVelocity = b3MakeVector3(0, -1, 0);
				break;
			}
			case 4:
			{
				m_bodies[i]->m_linearVelocity = b3MakeVector3(0, 0, 1);
				break;
			}
			case 5:
			{
				m_bodies[i]->m_linearVelocity = b3MakeVector3(0, 0, -1);
				break;
			}
			case 6:
			{
				m_bodies[i]->m_linearVelocity = b3MakeVector3(0, 0, 0);
				m_bodies[i]->m_angularVelocity = b3MakeVector3(1, 0, 0);
				break;
			}
			case 7:
			{
				m_bodies[i]->m_angularVelocity = b3MakeVector3(-1, 0, 0);
				break;
			}
			case 8:
			{
				m_bodies[i]->m_angularVelocity = b3MakeVector3(0, 1, 0);
				break;
			}
			case 9:
			{
				m_bodies[i]->m_angularVelocity = b3MakeVector3(0, -1, 0);
				break;
			}
			case 10:
			{
				m_bodies[i]->m_angularVelocity = b3MakeVector3(0, 0, 1);
				break;
			}
			case 11:
			{
				m_bodies[i]->m_angularVelocity = b3MakeVector3(0, 0, -1);
				break;
			}
			default:
			{
				m_bodies[i]->m_angularVelocity = b3MakeVector3(0, 0, 0);
			}
		};
	}

	m_counter++;
	if (m_counter > 60)
	{
		m_counter = 0;
		m_stage++;
		if (m_stage > 11)
			m_stage = 0;
		b3Printf("Stage = %d\n", m_stage);
		b3Printf("linVel = %f,%f,%f\n", m_bodies[0]->m_linearVelocity.x, m_bodies[0]->m_linearVelocity.y, m_bodies[0]->m_linearVelocity.z);
		b3Printf("angVel = %f,%f,%f\n", m_bodies[0]->m_angularVelocity.x, m_bodies[0]->m_angularVelocity.y, m_bodies[0]->m_angularVelocity.z);
	}
}

void Tutorial::tutorialSolveContactConstraintUpdate(float deltaTime, LWContactPoint& contact)
{
	ComputeClosestPointsSphereSphere(m_bodies[0]->m_collisionShape.m_sphere,
									 m_bodies[0]->m_worldPose,
									 m_bodies[1]->m_collisionShape.m_sphere,
									 m_bodies[1]->m_worldPose,
									 contact);
}

void Tutorial::tutorialCollisionUpdate(float deltaTime, LWContactPoint& contact)
{
	m_bodies[1]->m_worldPose.m_position.z = 3;

	ComputeClosestPointsSphereSphere(m_bodies[0]->m_collisionShape.m_sphere,
									 m_bodies[0]->m_worldPose,
									 m_bodies[1]->m_collisionShape.m_sphere,
									 m_bodies[1]->m_worldPose,
									 contact);

	switch (m_stage)
	{
		case 0:
		{
			m_bodies[0]->m_angularVelocity = b3MakeVector3(0, 0, 0);
			m_bodies[0]->m_linearVelocity = b3MakeVector3(1, 0, 0);
			break;
		}
		case 1:
		{
			m_bodies[0]->m_linearVelocity = b3MakeVector3(-1, 0, 0);
			break;
		}
		case 2:
		{
			m_bodies[0]->m_linearVelocity = b3MakeVector3(0, 1, 0);
			break;
		}
		case 3:
		{
			m_bodies[0]->m_linearVelocity = b3MakeVector3(0, -1, 0);
			break;
		}
		case 4:
		{
			m_bodies[0]->m_linearVelocity = b3MakeVector3(0, 0, 1);
			break;
		}
		case 5:
		{
			m_bodies[0]->m_linearVelocity = b3MakeVector3(0, 0, -1);
			break;
		}
		default:
		{
		}
	};
	m_counter++;
	if (m_counter > 120)
	{
		m_counter = 0;
		m_stage++;
		if (m_stage > 5)
			m_stage = 0;
	}
}

class CommonExampleInterface* TutorialCreateFunc(struct CommonExampleOptions& options)
{
	return new Tutorial(options.m_guiHelper, options.m_option);
}