/* Copyright (c) <2003-2011> <Julio Jerez, Newton Game Dynamics>
* 
* This software is provided 'as-is', without any express or implied
* warranty. In no event will the authors be held liable for any damages
* arising from the use of this software.
* 
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
* 
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software. If you use this software
* in a product, an acknowledgment in the product documentation would be
* appreciated but is not required.
* 
* 2. Altered source versions must be plainly marked as such, and must not be
* misrepresented as being the original software.
* 
* 3. This notice may not be removed or altered from any source distribution.
*/

#include "dgPhysicsStdafx.h"
#include "dgBody.h"
#include "dgWorld.h"
#include "dgCorkscrewConstraint.h"



//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

dgCorkscrewConstraint::dgCorkscrewConstraint ()
	:dgBilateralConstraint() 
{

	_ASSERTE ((((dgUnsigned64) &m_localMatrix0) & 15) == 0);

	m_maxDOF = 6;
	m_constId = dgCorkscrewConstraintId;
	m_posit = dgFloat32 (0.0f);
	m_angle = dgFloat32 (0.0f);
	m_jointAccelFnt = NULL;
}

dgCorkscrewConstraint::~dgCorkscrewConstraint ()
{
}

/*
dgCorkscrewConstraint* dgCorkscrewConstraint::Create(dgWorld* world)
{
	dgCorkscrewConstraint*	constraint;

//	constraint = dgCorkscrewConstraintArray::GetPool().GetElement();
	dgCorkscrewConstraintArray& array = * world;
	constraint = array.GetElement();

	_ASSERTE ((((dgUnsigned64) &constraint->m_localMatrix0) & 15) == 0);
	constraint->Init ();
	constraint->m_maxDOF = 6;
	constraint->m_constId = dgCorkscrewConstraintId;

	constraint->m_posit = dgFloat32 (0.0f);
	constraint->m_angle = dgFloat32 (0.0f);
	constraint->m_jointAccelFnt = NULL;
	return constraint;
}

void dgCorkscrewConstraint::Remove(dgWorld* world)
{
	dgCorkscrewConstraintArray& array = * world;

	dgBilateralConstraint::Remove (world);
//	dgCorkscrewConstraintArray::GetPool().RemoveElement (this);
	array.RemoveElement (this);
}
*/

void dgCorkscrewConstraint::SetJointParameterCallBack (dgCorkscrewJointAcceleration callback)
{
	m_jointAccelFnt = callback;
}

dgFloat32 dgCorkscrewConstraint::GetJointAngle () const
{
	return m_angle;
}

dgFloat32 dgCorkscrewConstraint::GetJointPosit () const
{
	return m_posit;
}


dgFloat32 dgCorkscrewConstraint::GetJointOmega () const
{
	_ASSERTE (m_body0);
	_ASSERTE (m_body1);
	dgVector dir (m_body0->GetMatrix().RotateVector (m_localMatrix0[0]));
	const dgVector& omega0 = m_body0->GetOmega();
	const dgVector& omega1 = m_body1->GetOmega();

//	dgVector omega1 (dgFloat32 (0.0f), dgFloat32 (0.0f), dgFloat32 (0.0f), dgFloat32 (0.0f));
//	if (m_body1) {
//		omega1 = m_body1->GetOmega();
//	}
	return (omega0 - omega1) % dir;
}

dgFloat32 dgCorkscrewConstraint::GetJointVeloc () const
{
	_ASSERTE (m_body0);
	_ASSERTE (m_body1);
	dgVector dir (m_body0->GetMatrix().RotateVector (m_localMatrix0[0]));
	const dgVector& veloc0 = m_body0->GetVelocity();
	const dgVector& veloc1 = m_body1->GetVelocity();

//	dgVector veloc1 (dgFloat32 (0.0f), dgFloat32 (0.0f), dgFloat32 (0.0f), dgFloat32 (0.0f));
//	if (m_body1) {
//		veloc1 = m_body1->GetVelocity();
//	}
	return (veloc0 - veloc1) % dir;
}


dgFloat32 dgCorkscrewConstraint::CalculateStopAlpha (dgFloat32 angle, const dgJointCallBackParam* param) const
{
	dgFloat32 alpha;
	dgFloat32 omega;
	dgFloat32 penetrationErr;

	alpha = dgFloat32 (0.0f);
	if (m_angle > angle) {
		omega = GetJointOmega ();
		if (omega < dgFloat32 (0.0f)) {
			omega = dgFloat32 (0.0f);
		}
		penetrationErr = angle - m_angle; 
		alpha = dgFloat32 (100.0f) * penetrationErr - omega * dgFloat32 (1.01f) / param->m_timestep;

	} else if (m_angle < angle) {
		omega = GetJointOmega ();
		if (omega > dgFloat32 (0.0f)) {
			omega = dgFloat32 (0.0f);
		}

		penetrationErr = angle - m_angle; 
		alpha = dgFloat32 (100.0f) * penetrationErr - omega * dgFloat32 (1.01f) / param->m_timestep;
	} 
	return alpha;
}

dgFloat32 dgCorkscrewConstraint::CalculateStopAccel (dgFloat32 distance, const dgJointCallBackParam* param) const
{
	dgFloat32 accel;
	dgFloat32 speed;
	dgFloat32 penetrationErr;

	accel = dgFloat32 (0.0f);
	if (m_posit > distance) {
		speed = GetJointVeloc ();
		if (speed < dgFloat32 (0.0f)) {
			speed = dgFloat32 (0.0f);
		}
		penetrationErr = (distance - m_posit); 
		accel = dgFloat32 (100.0f) * penetrationErr - speed * dgFloat32 (1.01f) / param->m_timestep;

	} else if (m_posit < distance) {
		speed = GetJointVeloc ();
		if (speed > dgFloat32 (0.0f)) {
			speed = dgFloat32 (0.0f);
		}
		penetrationErr = distance - m_posit; 
		_ASSERTE (penetrationErr >= dgFloat32 (0.0f));
		accel = dgFloat32 (100.0f) * penetrationErr - speed * dgFloat32 (1.01f) / param->m_timestep;
	} 
	return accel;
}


dgVector dgCorkscrewConstraint::GetJointForce () const
{
	dgMatrix matrix0;
	dgMatrix matrix1;

	CalculateGlobalMatrixAndAngle (matrix0, matrix1);

	return dgVector (matrix0.m_up.Scale (m_jointForce[0]) + 
		             matrix0.m_right.Scale (m_jointForce[1]) + 
					 matrix0.m_up.Scale (m_jointForce[2]) +
					 matrix0.m_right.Scale (m_jointForce[3]));

}

dgUnsigned32 dgCorkscrewConstraint::JacobianDerivative (dgContraintDescritor& params)
{
	dgMatrix matrix0;
	dgMatrix matrix1;

	dgVector angle (CalculateGlobalMatrixAndAngle (matrix0, matrix1));

	m_angle = -angle.m_x;
	m_posit = (matrix0.m_posit - matrix1.m_posit) % matrix0.m_front;
	matrix1.m_posit += matrix1.m_front.Scale (m_posit);

	_ASSERTE (dgAbsf (dgFloat32 (1.0f) - (matrix0.m_front % matrix0.m_front)) < dgFloat32 (1.0e-5f)); 
	_ASSERTE (dgAbsf (dgFloat32 (1.0f) - (matrix0.m_up % matrix0.m_up)) < dgFloat32 (1.0e-5f)); 
	_ASSERTE (dgAbsf (dgFloat32 (1.0f) - (matrix0.m_right % matrix0.m_right)) < dgFloat32 (1.0e-5f)); 

	const dgVector& dir1 = matrix0.m_up;
	const dgVector& dir2 = matrix0.m_right;

//	const dgVector& p0 = matrix0.m_posit;
//	const dgVector& p1 = matrix1.m_posit;
	dgVector p0 (matrix0.m_posit);
	dgVector p1 (matrix1.m_posit + matrix1.m_front.Scale ((p0 - matrix1.m_posit) % matrix1.m_front));

	dgVector q0 (p0 + matrix0.m_front.Scale(MIN_JOINT_PIN_LENGTH));
	dgVector q1 (p1 + matrix1.m_front.Scale(MIN_JOINT_PIN_LENGTH));

	dgPointParam pointDataP;
	dgPointParam pointDataQ;
	InitPointParam (pointDataP, m_stiffness, p0, p1);
	InitPointParam (pointDataQ, m_stiffness, q0, q1);

	CalculatePointDerivative (0, params, dir1, pointDataP, &m_jointForce[0]); 
	CalculatePointDerivative (1, params, dir2, pointDataP, &m_jointForce[1]); 
	CalculatePointDerivative (2, params, dir1, pointDataQ, &m_jointForce[2]); 
	CalculatePointDerivative (3, params, dir2, pointDataQ, &m_jointForce[3]); 

	dgInt32 ret = 4;
	if (m_jointAccelFnt) {
		dgUnsigned32 code;
		dgJointCallBackParam axisParam[2];

		// linear acceleration
		axisParam[0].m_accel = dgFloat32 (0.0f);
		axisParam[0].m_timestep = params.m_timestep;
		axisParam[0].m_minFriction = DG_MIN_BOUND;
		axisParam[0].m_maxFriction = DG_MAX_BOUND;

		// angular acceleration
		axisParam[1].m_accel = dgFloat32 (0.0f);
		axisParam[1].m_timestep = params.m_timestep;
		axisParam[1].m_minFriction = DG_MIN_BOUND;
		axisParam[1].m_maxFriction = DG_MAX_BOUND;

		code = m_jointAccelFnt (*this, axisParam);
		if (code & 1) {
			if ((axisParam[0].m_minFriction > DG_MIN_BOUND) || (axisParam[0].m_maxFriction < DG_MAX_BOUND)) {
				params.m_forceBounds[ret].m_low = axisParam[0].m_minFriction;
				params.m_forceBounds[ret].m_upper = axisParam[0].m_maxFriction;
				params.m_forceBounds[ret].m_normalIndex = DG_BILATERAL_FRICTION_CONSTRAINT;
			}

			CalculatePointDerivative (ret, params, matrix0.m_front, pointDataP, &m_jointForce[ret]); 
			//params.m_jointAccel[ret] = axisParam[0].m_accel;
			SetMotorAcceleration (ret, axisParam[0].m_accel, params);
			ret ++;
		}


		if (code & 2) {
			if ((axisParam[1].m_minFriction > DG_MIN_BOUND) || (axisParam[1].m_maxFriction < DG_MAX_BOUND)) {
				params.m_forceBounds[ret].m_low = axisParam[1].m_minFriction;
				params.m_forceBounds[ret].m_upper = axisParam[1].m_maxFriction;
				params.m_forceBounds[ret].m_normalIndex = DG_BILATERAL_FRICTION_CONSTRAINT;
			}

//			dgVector p (p0 +  dir1);
//			dgPointParam pointData;
//			InitPointParam (pointData, m_stiffness, p, p);
//			CalculatePointDerivative (ret, params, dir2, pointData, &m_jointForce[ret]); 
			CalculateAngularDerivative (ret, params, matrix0.m_front, m_stiffness, dgFloat32 (0.0f), &m_jointForce[ret]);
			//params.m_jointAccel[ret] = axisParam[1].m_accel;
			SetMotorAcceleration (ret, axisParam[1].m_accel, params);
			ret ++;
		}
	}

	return dgUnsigned32 (ret);
}