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#include "foundation/PxMemory.h"
#include "DyConstraintPrep.h"
#include "PxsRigidBody.h"
#include "DySolverConstraint1D.h"
#include "DySolverConstraint1D4.h"
#include "foundation/PxSort.h"
#include "PxcConstraintBlockStream.h"
#include "DyArticulationContactPrep.h"
#include "DyAllocator.h"

namespace physx
{

using namespace aos;

namespace Dy
{

SolverConstraintPrepState::Enum setupSolverConstraint4
		(PxSolverConstraintPrepDesc* PX_RESTRICT constraintDescs,
		const PxReal dt, const PxReal recipdt, PxU32& totalRows,
		PxConstraintAllocator& allocator, PxU32 maxRows, bool residualReportingEnabled);

SolverConstraintPrepState::Enum setupSolverConstraint4
(SolverConstraintShaderPrepDesc* PX_RESTRICT constraintShaderDescs,
PxSolverConstraintPrepDesc* PX_RESTRICT constraintDescs,
const PxReal dt, const PxReal recipdt, PxU32& totalRows,
PxConstraintAllocator& allocator, bool residualReportingEnabled)

{
	//KS - we will never get here with constraints involving articulations so we don't need to stress about those in here

	totalRows = 0;

	Px1DConstraint allRows[MAX_CONSTRAINT_ROWS * 4];
	Px1DConstraint* rows = allRows;
	Px1DConstraint* rows2 = allRows;
	
	PxU32 maxRows = 0;
	PxU32 nbToPrep = MAX_CONSTRAINT_ROWS;

	for (PxU32 a = 0; a < 4; ++a)
	{
		SolverConstraintShaderPrepDesc& shaderDesc = constraintShaderDescs[a];
		PxSolverConstraintPrepDesc& desc = constraintDescs[a];

		if (!shaderDesc.solverPrep)
			return SolverConstraintPrepState::eUNBATCHABLE;

		PX_ASSERT(rows2 + nbToPrep <= allRows + MAX_CONSTRAINT_ROWS*4);
		setupConstraintRows(rows2, nbToPrep);
		rows2 += nbToPrep;

		desc.invMassScales.linear0 = desc.invMassScales.linear1 = desc.invMassScales.angular0 = desc.invMassScales.angular1 = 1.0f;
		desc.body0WorldOffset = PxVec3(0.0f);

		PxVec3p unused_ra, unused_rb;

		//TAG:solverprepcall
		const PxU32 constraintCount = desc.disableConstraint ? 0 : (*shaderDesc.solverPrep)(rows,
			desc.body0WorldOffset,
			MAX_CONSTRAINT_ROWS,
			desc.invMassScales,
			shaderDesc.constantBlock,
			desc.bodyFrame0, desc.bodyFrame1, desc.extendedLimits, unused_ra, unused_rb);

		nbToPrep = constraintCount;
		maxRows = PxMax(constraintCount, maxRows);

		if (constraintCount == 0)
			return SolverConstraintPrepState::eUNBATCHABLE;

		desc.rows = rows;
		desc.numRows = constraintCount;
		rows += constraintCount;
	}

	return setupSolverConstraint4(constraintDescs, dt, recipdt, totalRows, allocator, maxRows, residualReportingEnabled);
}

SolverConstraintPrepState::Enum setupSolverConstraint4
(PxSolverConstraintPrepDesc* PX_RESTRICT constraintDescs,
const PxReal simDt, const PxReal recipSimDt, PxU32& totalRows,
PxConstraintAllocator& allocator, PxU32 maxRows, bool residualReportingEnabled)
{
	const Vec4V zero = V4Zero();
	Px1DConstraint* allSorted[MAX_CONSTRAINT_ROWS * 4];
	PxU32 startIndex[4];
	PX_ALIGN(16, PxVec4) angSqrtInvInertia0[MAX_CONSTRAINT_ROWS * 4];
	PX_ALIGN(16, PxVec4) angSqrtInvInertia1[MAX_CONSTRAINT_ROWS * 4];

	PxU32 numRows = 0;

	for (PxU32 a = 0; a < 4; ++a)
	{
		startIndex[a] = numRows;
		PxSolverConstraintPrepDesc& desc = constraintDescs[a];
		Px1DConstraint** sorted = allSorted + numRows;

		preprocessRows(sorted, desc.rows, angSqrtInvInertia0 + numRows, angSqrtInvInertia1 + numRows, desc.numRows, 
			desc.data0->sqrtInvInertia, desc.data1->sqrtInvInertia, desc.data0->invMass, desc.data1->invMass, 
			desc.invMassScales, desc.disablePreprocessing, desc.improvedSlerp);

		numRows += desc.numRows;
	}

	const PxU32 stride = residualReportingEnabled ? sizeof(SolverConstraint1DDynamic4WithResidual) : sizeof(SolverConstraint1DDynamic4);

	const PxU32 constraintLength = sizeof(SolverConstraint1DHeader4) + stride * maxRows;

	//KS - +16 is for the constraint progress counter, which needs to be the last element in the constraint (so that we
	//know SPU DMAs have completed)
	PxU8* ptr = allocator.reserveConstraintData(constraintLength + 16u);
	if(!checkConstraintDataPtr<true>(ptr))
	{
		for(PxU32 a = 0; a < 4; ++a)
		{
			PxSolverConstraintPrepDesc& desc = constraintDescs[a];
			desc.desc->constraint = NULL;
			setConstraintLength(*desc.desc, 0);
			desc.desc->writeBack = desc.writeback;
		}

		return SolverConstraintPrepState::eOUT_OF_MEMORY;
	}

	//desc.constraint = ptr;

	totalRows = numRows;

	for(PxU32 a = 0; a < 4; ++a)
	{
		PxSolverConstraintPrepDesc& desc = constraintDescs[a];
		desc.desc->constraint = ptr;
		setConstraintLength(*desc.desc, constraintLength);
		desc.desc->writeBack = desc.writeback;
	}

	const PxReal erp[4] = { 1.0f, 1.0f, 1.0f, 1.0f};
	//OK, now we build all 4 constraints into a single set of rows

	{
		PxU8* currPtr = ptr;
		SolverConstraint1DHeader4* header = reinterpret_cast<SolverConstraint1DHeader4*>(currPtr);
		currPtr += sizeof(SolverConstraint1DHeader4);

		const PxSolverBodyData& bd00 = *constraintDescs[0].data0;
		const PxSolverBodyData& bd01 = *constraintDescs[1].data0;
		const PxSolverBodyData& bd02 = *constraintDescs[2].data0;
		const PxSolverBodyData& bd03 = *constraintDescs[3].data0;

		const PxSolverBodyData& bd10 = *constraintDescs[0].data1;
		const PxSolverBodyData& bd11 = *constraintDescs[1].data1;
		const PxSolverBodyData& bd12 = *constraintDescs[2].data1;
		const PxSolverBodyData& bd13 = *constraintDescs[3].data1;

		//Load up masses, invInertia, velocity etc.

		const Vec4V invMassScale0 = V4LoadXYZW(constraintDescs[0].invMassScales.linear0, constraintDescs[1].invMassScales.linear0, 
			constraintDescs[2].invMassScales.linear0, constraintDescs[3].invMassScales.linear0);
		const Vec4V invMassScale1 = V4LoadXYZW(constraintDescs[0].invMassScales.linear1, constraintDescs[1].invMassScales.linear1, 
			constraintDescs[2].invMassScales.linear1, constraintDescs[3].invMassScales.linear1);

		const Vec4V iMass0 = V4LoadXYZW(bd00.invMass, bd01.invMass, bd02.invMass, bd03.invMass);

		const Vec4V iMass1 = V4LoadXYZW(bd10.invMass, bd11.invMass, bd12.invMass, bd13.invMass);

		const Vec4V invMass0 = V4Mul(iMass0, invMassScale0);
		const Vec4V invMass1 = V4Mul(iMass1, invMassScale1);

		const Vec4V invInertiaScale0 = V4LoadXYZW(constraintDescs[0].invMassScales.angular0, constraintDescs[1].invMassScales.angular0, 
			constraintDescs[2].invMassScales.angular0, constraintDescs[3].invMassScales.angular0);
		const Vec4V invInertiaScale1 = V4LoadXYZW(constraintDescs[0].invMassScales.angular1, constraintDescs[1].invMassScales.angular1, 
			constraintDescs[2].invMassScales.angular1, constraintDescs[3].invMassScales.angular1);

		//Velocities
		Vec4V linVel00 = V4LoadA(&bd00.linearVelocity.x);
		Vec4V linVel01 = V4LoadA(&bd10.linearVelocity.x);
		Vec4V angVel00 = V4LoadA(&bd00.angularVelocity.x);
		Vec4V angVel01 = V4LoadA(&bd10.angularVelocity.x);

		Vec4V linVel10 = V4LoadA(&bd01.linearVelocity.x);
		Vec4V linVel11 = V4LoadA(&bd11.linearVelocity.x);
		Vec4V angVel10 = V4LoadA(&bd01.angularVelocity.x);
		Vec4V angVel11 = V4LoadA(&bd11.angularVelocity.x);

		Vec4V linVel20 = V4LoadA(&bd02.linearVelocity.x);
		Vec4V linVel21 = V4LoadA(&bd12.linearVelocity.x);
		Vec4V angVel20 = V4LoadA(&bd02.angularVelocity.x);
		Vec4V angVel21 = V4LoadA(&bd12.angularVelocity.x);

		Vec4V linVel30 = V4LoadA(&bd03.linearVelocity.x);
		Vec4V linVel31 = V4LoadA(&bd13.linearVelocity.x);
		Vec4V angVel30 = V4LoadA(&bd03.angularVelocity.x);
		Vec4V angVel31 = V4LoadA(&bd13.angularVelocity.x);

		Vec4V linVel0T0, linVel0T1, linVel0T2;
		Vec4V linVel1T0, linVel1T1, linVel1T2;
		Vec4V angVel0T0, angVel0T1, angVel0T2;
		Vec4V angVel1T0, angVel1T1, angVel1T2;

		PX_TRANSPOSE_44_34(linVel00, linVel10, linVel20, linVel30, linVel0T0, linVel0T1, linVel0T2);
		PX_TRANSPOSE_44_34(linVel01, linVel11, linVel21, linVel31, linVel1T0, linVel1T1, linVel1T2);
		PX_TRANSPOSE_44_34(angVel00, angVel10, angVel20, angVel30, angVel0T0, angVel0T1, angVel0T2);
		PX_TRANSPOSE_44_34(angVel01, angVel11, angVel21, angVel31, angVel1T0, angVel1T1, angVel1T2);

		//body world offsets
		Vec4V workOffset0 = V4LoadU(&constraintDescs[0].body0WorldOffset.x);
		Vec4V workOffset1 = V4LoadU(&constraintDescs[1].body0WorldOffset.x);
		Vec4V workOffset2 = V4LoadU(&constraintDescs[2].body0WorldOffset.x);
		Vec4V workOffset3 = V4LoadU(&constraintDescs[3].body0WorldOffset.x);

		Vec4V workOffsetX, workOffsetY, workOffsetZ;

		PX_TRANSPOSE_44_34(workOffset0, workOffset1, workOffset2, workOffset3, workOffsetX, workOffsetY, workOffsetZ);

		const FloatV dtV = FLoad(simDt);
		const Vec4V linBreakForce = V4LoadXYZW(	constraintDescs[0].linBreakForce, constraintDescs[1].linBreakForce,
												constraintDescs[2].linBreakForce, constraintDescs[3].linBreakForce);
		const Vec4V angBreakForce = V4LoadXYZW(	constraintDescs[0].angBreakForce, constraintDescs[1].angBreakForce,
												constraintDescs[2].angBreakForce, constraintDescs[3].angBreakForce);

		header->break0 = PxU8((constraintDescs[0].linBreakForce != PX_MAX_F32) || (constraintDescs[0].angBreakForce != PX_MAX_F32));
		header->break1 = PxU8((constraintDescs[1].linBreakForce != PX_MAX_F32) || (constraintDescs[1].angBreakForce != PX_MAX_F32));
		header->break2 = PxU8((constraintDescs[2].linBreakForce != PX_MAX_F32) || (constraintDescs[2].angBreakForce != PX_MAX_F32));
		header->break3 = PxU8((constraintDescs[3].linBreakForce != PX_MAX_F32) || (constraintDescs[3].angBreakForce != PX_MAX_F32));

		//OK, I think that's everything loaded in

		header->invMass0D0 = invMass0;
		header->invMass1D1 = invMass1;
		header->angD0 = invInertiaScale0;
		header->angD1 = invInertiaScale1;
		header->body0WorkOffsetX = workOffsetX;
		header->body0WorkOffsetY = workOffsetY;
		header->body0WorkOffsetZ = workOffsetZ;

		header->count = maxRows;
		header->type = DY_SC_TYPE_BLOCK_1D;
		header->linBreakImpulse = V4Scale(linBreakForce, dtV);
		header->angBreakImpulse = V4Scale(angBreakForce, dtV);
		header->count0 = PxTo8(constraintDescs[0].numRows);
		header->count1 = PxTo8(constraintDescs[1].numRows);
		header->count2 = PxTo8(constraintDescs[2].numRows);
		header->count3 = PxTo8(constraintDescs[3].numRows);

		//Now we loop over the constraints and build the results...

		PxU32 index0 = 0;
		PxU32 endIndex0 = constraintDescs[0].numRows - 1;
		PxU32 index1 = startIndex[1];
		PxU32 endIndex1 = index1 + constraintDescs[1].numRows - 1;
		PxU32 index2 = startIndex[2];
		PxU32 endIndex2 = index2 + constraintDescs[2].numRows - 1;
		PxU32 index3 = startIndex[3];
		PxU32 endIndex3 = index3 + constraintDescs[3].numRows - 1;

		for(PxU32 a = 0; a < maxRows; ++a)
		{	
			SolverConstraint1DDynamic4* c = reinterpret_cast<SolverConstraint1DDynamic4*>(currPtr);
			currPtr += stride;

			Px1DConstraint* con0 = allSorted[index0];
			Px1DConstraint* con1 = allSorted[index1];
			Px1DConstraint* con2 = allSorted[index2];
			Px1DConstraint* con3 = allSorted[index3];

			Vec4V cangDelta00 = V4LoadA(&angSqrtInvInertia0[index0].x);
			Vec4V cangDelta01 = V4LoadA(&angSqrtInvInertia0[index1].x);
			Vec4V cangDelta02 = V4LoadA(&angSqrtInvInertia0[index2].x);
			Vec4V cangDelta03 = V4LoadA(&angSqrtInvInertia0[index3].x);

			Vec4V cangDelta10 = V4LoadA(&angSqrtInvInertia1[index0].x);
			Vec4V cangDelta11 = V4LoadA(&angSqrtInvInertia1[index1].x);
			Vec4V cangDelta12 = V4LoadA(&angSqrtInvInertia1[index2].x);
			Vec4V cangDelta13 = V4LoadA(&angSqrtInvInertia1[index3].x);

			index0 = index0 == endIndex0 ? index0 : index0 + 1;
			index1 = index1 == endIndex1 ? index1 : index1 + 1;
			index2 = index2 == endIndex2 ? index2 : index2 + 1;
			index3 = index3 == endIndex3 ? index3 : index3 + 1;

			PxReal minImpulse0, minImpulse1, minImpulse2, minImpulse3;
			PxReal maxImpulse0, maxImpulse1, maxImpulse2, maxImpulse3;
			Dy::computeMinMaxImpulseOrForceAsImpulse(
				con0->minImpulse, con0->maxImpulse,		
				con0->flags & Px1DConstraintFlag::eHAS_DRIVE_LIMIT, constraintDescs[0].driveLimitsAreForces, simDt,
				minImpulse0, maxImpulse0);
			Dy::computeMinMaxImpulseOrForceAsImpulse(
				con1->minImpulse, con1->maxImpulse,		
				con1->flags & Px1DConstraintFlag::eHAS_DRIVE_LIMIT, constraintDescs[1].driveLimitsAreForces, simDt,
				minImpulse1, maxImpulse1);
			Dy::computeMinMaxImpulseOrForceAsImpulse(
				con2->minImpulse, con2->maxImpulse,		
				con2->flags & Px1DConstraintFlag::eHAS_DRIVE_LIMIT, constraintDescs[2].driveLimitsAreForces, simDt,
				minImpulse2, maxImpulse2);
			Dy::computeMinMaxImpulseOrForceAsImpulse(
				con3->minImpulse, con3->maxImpulse,		
				con3->flags & Px1DConstraintFlag::eHAS_DRIVE_LIMIT, constraintDescs[3].driveLimitsAreForces, simDt,
				minImpulse3, maxImpulse3);
			const Vec4V minImpulse = V4LoadXYZW(minImpulse0, minImpulse1, minImpulse2, minImpulse3);
			const Vec4V maxImpulse = V4LoadXYZW(maxImpulse0, maxImpulse1, maxImpulse2, maxImpulse3);
			
			Vec4V clin00 = V4LoadA(&con0->linear0.x);
			Vec4V clin01 = V4LoadA(&con1->linear0.x);
			Vec4V clin02 = V4LoadA(&con2->linear0.x);
			Vec4V clin03 = V4LoadA(&con3->linear0.x);

			Vec4V cang00 = V4LoadA(&con0->angular0.x);
			Vec4V cang01 = V4LoadA(&con1->angular0.x);
			Vec4V cang02 = V4LoadA(&con2->angular0.x);
			Vec4V cang03 = V4LoadA(&con3->angular0.x);

			Vec4V clin0X, clin0Y, clin0Z;
			Vec4V cang0X, cang0Y, cang0Z;
			
			PX_TRANSPOSE_44_34(clin00, clin01, clin02, clin03, clin0X, clin0Y, clin0Z);
			PX_TRANSPOSE_44_34(cang00, cang01, cang02, cang03, cang0X, cang0Y, cang0Z);
			
			Vec4V angDelta0X, angDelta0Y, angDelta0Z;

			PX_TRANSPOSE_44_34(cangDelta00, cangDelta01, cangDelta02, cangDelta03, angDelta0X, angDelta0Y, angDelta0Z);

			c->flags[0] = 0;
			c->flags[1] = 0;
			c->flags[2] = 0;
			c->flags[3] = 0;

			c->lin0X = clin0X;
			c->lin0Y = clin0Y;
			c->lin0Z = clin0Z;
			c->ang0X = angDelta0X;
			c->ang0Y = angDelta0Y;
			c->ang0Z = angDelta0Z;
			c->ang0WritebackX = cang0X;
			c->ang0WritebackY = cang0Y;
			c->ang0WritebackZ = cang0Z;

			c->minImpulse = minImpulse;
			c->maxImpulse = maxImpulse;
			c->appliedForce = zero;
			if (residualReportingEnabled) 
			{
				SolverConstraint1DDynamic4WithResidual* cc = static_cast<SolverConstraint1DDynamic4WithResidual*>(c);
				cc->residualPosIter = zero;
				cc->residualVelIter = zero;
			}

			const Vec4V lin0MagSq = V4MulAdd(clin0Z, clin0Z, V4MulAdd(clin0Y, clin0Y, V4Mul(clin0X, clin0X)));
			const Vec4V cang0DotAngDelta = V4MulAdd(angDelta0Z, angDelta0Z, V4MulAdd(angDelta0Y, angDelta0Y, V4Mul(angDelta0X, angDelta0X)));
			c->flags[0] = 0;
			c->flags[1] = 0;
			c->flags[2] = 0;
			c->flags[3] = 0;

			Vec4V unitResponse = V4MulAdd(lin0MagSq, invMass0, V4Mul(cang0DotAngDelta, invInertiaScale0));

			Vec4V clin10 = V4LoadA(&con0->linear1.x);
			Vec4V clin11 = V4LoadA(&con1->linear1.x);
			Vec4V clin12 = V4LoadA(&con2->linear1.x);
			Vec4V clin13 = V4LoadA(&con3->linear1.x);

			Vec4V cang10 = V4LoadA(&con0->angular1.x);
			Vec4V cang11 = V4LoadA(&con1->angular1.x);
			Vec4V cang12 = V4LoadA(&con2->angular1.x);
			Vec4V cang13 = V4LoadA(&con3->angular1.x);

			Vec4V clin1X, clin1Y, clin1Z;
			Vec4V cang1X, cang1Y, cang1Z;
			PX_TRANSPOSE_44_34(clin10, clin11, clin12, clin13, clin1X, clin1Y, clin1Z);
			PX_TRANSPOSE_44_34(cang10, cang11, cang12, cang13, cang1X, cang1Y, cang1Z);

			Vec4V angDelta1X, angDelta1Y, angDelta1Z;

			PX_TRANSPOSE_44_34(cangDelta10, cangDelta11, cangDelta12, cangDelta13, angDelta1X, angDelta1Y, angDelta1Z);

			const Vec4V lin1MagSq = V4MulAdd(clin1Z, clin1Z, V4MulAdd(clin1Y, clin1Y, V4Mul(clin1X, clin1X)));
			const Vec4V cang1DotAngDelta = V4MulAdd(angDelta1Z, angDelta1Z, V4MulAdd(angDelta1Y, angDelta1Y, V4Mul(angDelta1X, angDelta1X)));

			c->lin1X = clin1X;
			c->lin1Y = clin1Y;
			c->lin1Z = clin1Z;

			c->ang1X = angDelta1X;
			c->ang1Y = angDelta1Y;
			c->ang1Z = angDelta1Z;

			unitResponse = V4Add(unitResponse, V4MulAdd(lin1MagSq, invMass1, V4Mul(cang1DotAngDelta, invInertiaScale1)));

			Vec4V linProj0(V4Mul(clin0X, linVel0T0));
			Vec4V linProj1(V4Mul(clin1X, linVel1T0));
			Vec4V angProj0(V4Mul(cang0X, angVel0T0));
			Vec4V angProj1(V4Mul(cang1X, angVel1T0));

			linProj0 = V4MulAdd(clin0Y, linVel0T1, linProj0);
			linProj1 = V4MulAdd(clin1Y, linVel1T1, linProj1);
			angProj0 = V4MulAdd(cang0Y, angVel0T1, angProj0);
			angProj1 = V4MulAdd(cang1Y, angVel1T1, angProj1);
			
			linProj0 = V4MulAdd(clin0Z, linVel0T2, linProj0);
			linProj1 = V4MulAdd(clin1Z, linVel1T2, linProj1);
			angProj0 = V4MulAdd(cang0Z, angVel0T2, angProj0);
			angProj1 = V4MulAdd(cang1Z, angVel1T2, angProj1);

			const Vec4V projectVel0 = V4Add(linProj0, angProj0);
			const Vec4V projectVel1 = V4Add(linProj1, angProj1);
			
			const Vec4V normalVel = V4Sub(projectVel0, projectVel1);

			{
				//const inputs.
				const Px1DConstraint* constraints[4] ={con0, con1, con2, con3};
				const PxReal* unitResponses4 = reinterpret_cast<const PxReal*>(&unitResponse);
				const PxReal* initJointSpeeds4 = reinterpret_cast<const PxReal*>(&normalVel);

				//outputs
				PxReal* biasedConstants4 = reinterpret_cast<PxReal*>(&c->constant);
				PxReal* unbiasedConstants4 = reinterpret_cast<PxReal*>(&c->unbiasedConstant);
				PxReal* velMultipliers4 = reinterpret_cast<PxReal*>(&c->velMultiplier);
				PxReal* impulseMultipliers4 = reinterpret_cast<PxReal*>(&c->impulseMultiplier);

				for(PxU32 i = 0; i < 4; i++)
				{
					if(a < constraintDescs[i].numRows)
					{
						const PxReal minRowResponseI = constraintDescs[i].minResponseThreshold;
						const PxU16 constraintFlagsI = constraints[i]->flags;
						const PxReal stiffnessI = constraints[i]->mods.spring.stiffness;
						const PxReal dampingI = constraints[i]->mods.spring.damping;
						const PxReal restitutionI = constraints[i]->mods.bounce.restitution;
						const PxReal bounceVelocityThresholdI = constraints[i]->mods.bounce.velocityThreshold;
						const PxReal geometricErrorI = constraints[i]->geometricError;
						const PxReal velocityTargetI = constraints[i]->velocityTarget;
						const PxReal jointSpeedForRestitutionBounceI = initJointSpeeds4[i];
						const PxReal initJointSpeedI = initJointSpeeds4[i];
						const PxReal unitResponseI = unitResponses4[i];
						const PxReal erpI = erp[i];
	
						const PxReal recipResponseI = computeRecipUnitResponse(unitResponseI, minRowResponseI);

						const Constraint1dSolverConstantsPGS solverConstants = 
							 Dy::compute1dConstraintSolverConstantsPGS(
								constraintFlagsI, 
								stiffnessI, dampingI, 
								restitutionI, bounceVelocityThresholdI,
								geometricErrorI, velocityTargetI,
								jointSpeedForRestitutionBounceI, initJointSpeedI,
								unitResponseI, recipResponseI, 
								erpI, 
								simDt, recipSimDt);					

						biasedConstants4[i] = solverConstants.constant;
						unbiasedConstants4[i] = solverConstants.unbiasedConstant;
						velMultipliers4[i] = solverConstants.velMultiplier;
						impulseMultipliers4[i] = solverConstants.impulseMultiplier;
					}
					else
					{
						biasedConstants4[i] = 0;
						unbiasedConstants4[i] = 0;
						velMultipliers4[i] = 0;
						impulseMultipliers4[i] = 0;
					}
				}
			}

			if(con0->flags & Px1DConstraintFlag::eOUTPUT_FORCE)
				c->flags[0] |= DY_SC_FLAG_OUTPUT_FORCE;
			if(con1->flags & Px1DConstraintFlag::eOUTPUT_FORCE)
				c->flags[1] |= DY_SC_FLAG_OUTPUT_FORCE;
			if(con2->flags & Px1DConstraintFlag::eOUTPUT_FORCE)
				c->flags[2] |= DY_SC_FLAG_OUTPUT_FORCE;
			if(con3->flags & Px1DConstraintFlag::eOUTPUT_FORCE)
				c->flags[3] |= DY_SC_FLAG_OUTPUT_FORCE;
		}
		*(reinterpret_cast<PxU32*>(currPtr)) = 0;
		*(reinterpret_cast<PxU32*>(currPtr + 4)) = 0;
	}
	
	//OK, we're ready to allocate and solve prep these constraints now :-)
	return SolverConstraintPrepState::eSUCCESS;
}

}

}