scummvm-cursorfix/engines/hpl1/engine/libraries/newton/physics/dgHingeConstraint.cpp

/* 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 "dgHingeConstraint.h"
#include "dgBody.h"
#include "dgWorld.h"
#include "hpl1/engine/libraries/newton/core/dg.h"


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

dgHingeConstraint::dgHingeConstraint() : dgBilateralConstraint() {
	NEWTON_ASSERT((((dgUnsigned64)&m_localMatrix0) & 15) == 0);
	//  constraint->Init ();

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

dgHingeConstraint::~dgHingeConstraint() {
}

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

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

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

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

 void dgHingeConstraint::Remove(dgWorld* world)
 {
 dgHingeConstraintArray& array = *world;
 dgBilateralConstraint::Remove (world);
 //dgHingeConstraintArray::GetPool().RemoveElement (this);
 array.RemoveElement (this);
 }
 */

void dgHingeConstraint::SetJointParameterCallBack(
    dgHingeJointAcceleration callback) {
	m_jointAccelFnt = callback;
}

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

dgFloat32 dgHingeConstraint::GetJointOmega() const {
	NEWTON_ASSERT(m_body0);
	NEWTON_ASSERT(m_body1);
	dgVector dir(m_body0->GetMatrix().RotateVector(m_localMatrix0[0]));
	const dgVector &omega0 = m_body0->GetOmega();
	const dgVector &omega1 = m_body1->GetOmega();
	return (omega0 - omega1) % dir;
}

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

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

	CalculateGlobalMatrixAndAngle(matrix0, matrix1);
	return dgVector(
	           matrix0.m_front.Scale(m_jointForce[0]) + matrix0.m_up.Scale(m_jointForce[1]) + matrix0.m_right.Scale(m_jointForce[2]) + matrix0.m_up.Scale(m_jointForce[3]) + matrix0.m_right.Scale(m_jointForce[4]));
}

dgUnsigned32 dgHingeConstraint::JacobianDerivative(dgContraintDescritor &params) {
	dgMatrix matrix0;
	dgMatrix matrix1;
	dgVector angle(CalculateGlobalMatrixAndAngle(matrix0, matrix1));

	m_angle = -angle.m_x;

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

	const dgVector &dir0 = matrix0.m_front;
	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 q0(p0 + matrix0.m_front.Scale(MIN_JOINT_PIN_LENGTH));
	dgVector q1(p1 + matrix1.m_front.Scale(MIN_JOINT_PIN_LENGTH));

	//  NEWTON_ASSERT (((p1 - p0) % (p1 - p0)) < 1.0e-2f);

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

	CalculatePointDerivative(0, params, dir0, pointDataP, &m_jointForce[0]);
	CalculatePointDerivative(1, params, dir1, pointDataP, &m_jointForce[1]);
	CalculatePointDerivative(2, params, dir2, pointDataP, &m_jointForce[2]);
	CalculatePointDerivative(3, params, dir1, pointDataQ, &m_jointForce[3]);
	CalculatePointDerivative(4, params, dir2, pointDataQ, &m_jointForce[4]);

	dgInt32 ret = 5;
	if (m_jointAccelFnt) {
		dgJointCallBackParam axisParam;
		axisParam.m_accel = dgFloat32(0.0f);
		axisParam.m_timestep = params.m_timestep;
		axisParam.m_minFriction = DG_MIN_BOUND;
		axisParam.m_maxFriction = DG_MAX_BOUND;

		if (m_jointAccelFnt(reinterpret_cast<NewtonJoint *>(this), reinterpret_cast<NewtonHingeSliderUpdateDesc *>(&axisParam))) {
			if ((axisParam.m_minFriction > DG_MIN_BOUND) || (axisParam.m_maxFriction < DG_MAX_BOUND)) {
				params.m_forceBounds[5].m_low = axisParam.m_minFriction;
				params.m_forceBounds[5].m_upper = axisParam.m_maxFriction;
				params.m_forceBounds[5].m_normalIndex = DG_BILATERAL_FRICTION_CONSTRAINT;
			}

			CalculateAngularDerivative(5, params, dir0, m_stiffness, dgFloat32(0.0f),
			                           &m_jointForce[5]);
			//          params.m_jointAccel[5] = axisParam.m_accel;
			SetMotorAcceleration(5, axisParam.m_accel, params);
			ret = 6;
		}
	}

	return dgUnsigned32(ret);
}