/*
 * 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.
 */



/*
	LinearConvexCastDemo implements an efficient continuous collision detection algorithm.
	Both linear and angular velocities are supported. Gjk or Simplex based methods.
	Motion using Exponential Map.
	Comparison with Screwing Motion. 
	Also comparision with Algebraic CCD and Interval Arithmetic methods (Stephane Redon)
*/


///Low level demo, doesn't include btBulletCollisionCommon.h
#include "LinearMath/SimdQuaternion.h"
#include "LinearMath/SimdTransform.h"
#include "BulletCollision/NarrowPhaseCollision/btVoronoiSimplexSolver.h"
#include "BulletCollision/CollisionShapes/btBoxShape.h"
#include "BulletCollision/CollisionShapes/btMinkowskiSumShape.h"

#include "BulletCollision/NarrowPhaseCollision/btGjkPairDetector.h"
#include "BulletCollision/NarrowPhaseCollision/btGjkConvexCast.h"
#include "BulletCollision/NarrowPhaseCollision/btContinuousConvexCollision.h"
#include "BulletCollision/NarrowPhaseCollision/btSubSimplexConvexCast.h"

#ifdef USE_ALGEBRAIC_CCD
#include "NarrowPhaseCollision/BU_CollisionPair.h"
#endif //USE_ALGEBRAIC_CCD

#include "BulletCollision/CollisionShapes/btSphereShape.h"
#include "BulletCollision/CollisionShapes/btTetrahedronShape.h"

#include "GL_ShapeDrawer.h"
#include "LinearConvexCastDemo.h"
#include "GlutStuff.h"


float yaw=0.f,pitch=0.f,roll=0.f;
const int maxNumObjects = 4;
const int numObjects = 2;


PolyhedralConvexShape*	shapePtr[maxNumObjects];

SimdTransform tr[numObjects];
int screenWidth = 640;
int screenHeight = 480;
void DrawRasterizerLine(float const* , float const*, int)
{

}

int main(int argc,char** argv)
{

	LinearConvexCastDemo* linearCastDemo = new LinearConvexCastDemo();

	linearCastDemo->initPhysics();


	return glutmain(argc, argv,screenWidth,screenHeight,"Linear Convex Cast Demo",linearCastDemo);
}

void LinearConvexCastDemo::initPhysics()
{
	setCameraDistance(30.f);
	tr[0].setOrigin(SimdVector3(0,0,0));
	tr[1].setOrigin(SimdVector3(0,10,0));

	SimdMatrix3x3 basisA;
	basisA.setValue(0.99999958f,0.00022980258f,0.00090992288f,
		-0.00029313788f,0.99753088f,0.070228584f,
		-0.00089153741f,-0.070228823f,0.99753052f);

	SimdMatrix3x3 basisB;
	basisB.setValue(1.0000000f,4.4865553e-018f,-4.4410586e-017f,
		4.4865495e-018f,0.97979438f,0.20000751f,
		4.4410586e-017f,-0.20000751f,0.97979438f);

	tr[0].setBasis(basisA);
	tr[1].setBasis(basisB);



	SimdVector3 boxHalfExtentsA(0.2,4,4);
	SimdVector3 boxHalfExtentsB(6,6,6);

	BoxShape*	boxA = new BoxShape(boxHalfExtentsA);
/*	BU_Simplex1to4	boxB;
	boxB.AddVertex(SimdPoint3(-5,0,-5));
	boxB.AddVertex(SimdPoint3(5,0,-5));
	boxB.AddVertex(SimdPoint3(0,0,5));
	boxB.AddVertex(SimdPoint3(0,5,0));
*/

	BoxShape*	boxB = new BoxShape(boxHalfExtentsB);
	shapePtr[0] = boxA;
	shapePtr[1] = boxB;

	shapePtr[0]->SetMargin(0.01f);
	shapePtr[1]->SetMargin(0.01f);

	SimdTransform tr;
	tr.setIdentity();
}

//to be implemented by the demo

void LinearConvexCastDemo::clientMoveAndDisplay()
{
	
	displayCallback();
}

#include "BulletCollision/NarrowPhaseCollision/btVoronoiSimplexSolver.h"
#include "BulletCollision/NarrowPhaseCollision/btConvexPenetrationDepthSolver.h"

static VoronoiSimplexSolver sVoronoiSimplexSolver;

SimplexSolverInterface& gGjkSimplexSolver = sVoronoiSimplexSolver;

bool drawLine= false;

void LinearConvexCastDemo::displayCallback(void) 
{
	updateCamera();

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); 
	glDisable(GL_LIGHTING);

	//GL_ShapeDrawer::DrawCoordSystem();

	float m[16];
	int i;

	for (i=0;i<numObjects;i++)
	{
		tr[i].getOpenGLMatrix( m );
		GL_ShapeDrawer::DrawOpenGL(m,shapePtr[i],SimdVector3(1,1,1),getDebugMode());
	}

	
	int shapeIndex = 1;

	SimdQuaternion orn;
	orn.setEuler(yaw,pitch,roll);
	tr[shapeIndex].setRotation(orn);
	

	if (m_stepping || m_singleStep)
	{
		m_singleStep = false;
		pitch += 0.005f;
		yaw += 0.01f;
	}

	SimdVector3 fromA(-25,11,0);
	SimdVector3 toA(15,11,0);

	SimdQuaternion ornFromA(0.f,0.f,0.f,1.f);
	SimdQuaternion ornToA(0.f,0.f,0.f,1.f);

	SimdTransform	rayFromWorld(ornFromA,fromA);
	SimdTransform	rayToWorld(ornToA,toA);

	tr[0] = rayFromWorld;

	if (drawLine)
	{
		glBegin(GL_LINES);
		glColor3f(0, 0, 1);
		glVertex3d(rayFromWorld.getOrigin().x(), rayFromWorld.getOrigin().y(),rayFromWorld.getOrigin().z());
		glVertex3d(rayToWorld.getOrigin().x(),rayToWorld.getOrigin().y(),rayToWorld.getOrigin().z());
		glEnd();
	}

	//now perform a raycast on the shapes, in local (shape) space
	
	//choose one of the following lines

	

	for (i=1;i<numObjects;i++)
	{
		ContinuousConvexCollision convexCaster0(shapePtr[0],shapePtr[i],&gGjkSimplexSolver,0);
		GjkConvexCast	convexCaster1(shapePtr[0],shapePtr[i],&gGjkSimplexSolver);
		
		//BU_CollisionPair (algebraic version) is currently broken, will look into this
		//BU_CollisionPair convexCaster2(shapePtr[0],shapePtr[i]);
		SubsimplexConvexCast convexCaster3(shapePtr[0],shapePtr[i],&gGjkSimplexSolver);
				
		gGjkSimplexSolver.reset();

		ConvexCast::CastResult rayResult;
		
	

		if (convexCaster3.calcTimeOfImpact(rayFromWorld,rayToWorld,tr[i],tr[i],rayResult))
		{

			glDisable(GL_DEPTH_TEST);
			SimdVector3 hitPoint;
			hitPoint.setInterpolate3(rayFromWorld.getOrigin(),rayToWorld.getOrigin(),rayResult.m_fraction);
			
			//draw the raycast result
			glBegin(GL_LINES);
			glColor3f(1, 1, 1);
			glVertex3d(rayFromWorld.getOrigin().x(), rayFromWorld.getOrigin().y(),rayFromWorld.getOrigin().z());
			glVertex3d(hitPoint.x(),hitPoint.y(),hitPoint.z());
			glEnd();
			glEnable(GL_DEPTH_TEST);

			SimdTransform	toTransWorld;
			toTransWorld = tr[0];
			toTransWorld.setOrigin(hitPoint);

			toTransWorld.getOpenGLMatrix( m );
			GL_ShapeDrawer::DrawOpenGL(m,shapePtr[0],SimdVector3(0,1,1),getDebugMode());


		}
	}

	glFlush();
    glutSwapBuffers();
}