Files
bullet3/Extras/quickstep/OdeTypedJoint.cpp
ejcoumans 811c105c24 align btQuadWord on 16byte boundary
slightly improved friction model
2007-09-25 06:58:53 +00:00

452 lines
13 KiB
C++

/*
Bullet Continuous Collision Detection and Physics Library
Copyright (c) 2003-2006 Erwin Coumans http://continuousphysics.com/Bullet/
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 "OdeTypedJoint.h"
#include "OdeSolverBody.h"
#include "OdeMacros.h"
#include <stdio.h>
void OdeTypedJoint::GetInfo1(Info1 *info)
{
int joint_type = m_constraint->getConstraintType();
switch (joint_type)
{
case POINT2POINT_CONSTRAINT_TYPE:
{
OdeP2PJoint p2pjoint(m_constraint,m_index,m_swapBodies,m_body0,m_body1);
p2pjoint.GetInfo1(info);
}
break;
case D6_CONSTRAINT_TYPE:
{
OdeD6Joint d6joint(m_constraint,m_index,m_swapBodies,m_body0,m_body1);
d6joint.GetInfo1(info);
}
break;
};
}
void OdeTypedJoint::GetInfo2(Info2 *info)
{
int joint_type = m_constraint->getConstraintType();
switch (joint_type)
{
case POINT2POINT_CONSTRAINT_TYPE:
{
OdeP2PJoint p2pjoint(m_constraint,m_index,m_swapBodies,m_body0,m_body1);
p2pjoint.GetInfo2(info);
}
break;
case D6_CONSTRAINT_TYPE:
{
OdeD6Joint d6joint(m_constraint,m_index,m_swapBodies,m_body0,m_body1);
d6joint.GetInfo2(info);
}
break;
};
}
OdeP2PJoint::OdeP2PJoint(
btTypedConstraint * constraint,
int index,bool swap,OdeSolverBody* body0,OdeSolverBody* body1):
OdeTypedJoint(constraint,index,swap,body0,body1)
{
}
void OdeP2PJoint::GetInfo1(Info1 *info)
{
info->m = 3;
info->nub = 3;
}
void OdeP2PJoint::GetInfo2(Info2 *info)
{
btPoint2PointConstraint * p2pconstraint = this->getP2PConstraint();
//retrieve matrices
btTransform body0_trans;
if (m_body0)
{
body0_trans = m_body0->m_originalBody->getCenterOfMassTransform();
}
// btScalar body0_mat[12];
// body0_mat[0] = body0_trans.getBasis()[0][0];
// body0_mat[1] = body0_trans.getBasis()[0][1];
// body0_mat[2] = body0_trans.getBasis()[0][2];
// body0_mat[4] = body0_trans.getBasis()[1][0];
// body0_mat[5] = body0_trans.getBasis()[1][1];
// body0_mat[6] = body0_trans.getBasis()[1][2];
// body0_mat[8] = body0_trans.getBasis()[2][0];
// body0_mat[9] = body0_trans.getBasis()[2][1];
// body0_mat[10] = body0_trans.getBasis()[2][2];
btTransform body1_trans;
if (m_body1)
{
body1_trans = m_body1->m_originalBody->getCenterOfMassTransform();
}
// btScalar body1_mat[12];
// body1_mat[0] = body1_trans.getBasis()[0][0];
// body1_mat[1] = body1_trans.getBasis()[0][1];
// body1_mat[2] = body1_trans.getBasis()[0][2];
// body1_mat[4] = body1_trans.getBasis()[1][0];
// body1_mat[5] = body1_trans.getBasis()[1][1];
// body1_mat[6] = body1_trans.getBasis()[1][2];
// body1_mat[8] = body1_trans.getBasis()[2][0];
// body1_mat[9] = body1_trans.getBasis()[2][1];
// body1_mat[10] = body1_trans.getBasis()[2][2];
// anchor points in global coordinates with respect to body PORs.
int s = info->rowskip;
// set jacobian
info->J1l[0] = 1;
info->J1l[s+1] = 1;
info->J1l[2*s+2] = 1;
btVector3 a1,a2;
a1 = body0_trans.getBasis()*p2pconstraint->getPivotInA();
//dMULTIPLY0_331 (a1, body0_mat,m_constraint->m_pivotInA);
dCROSSMAT (info->J1a,a1,s,-,+);
if (m_body1)
{
info->J2l[0] = -1;
info->J2l[s+1] = -1;
info->J2l[2*s+2] = -1;
a2 = body1_trans.getBasis()*p2pconstraint->getPivotInB();
//dMULTIPLY0_331 (a2,body1_mat,m_constraint->m_pivotInB);
dCROSSMAT (info->J2a,a2,s,+,-);
}
// set right hand side
btScalar k = info->fps * info->erp;
if (m_body1)
{
for (int j=0; j<3; j++)
{
info->c[j] = k * (a2[j] + body1_trans.getOrigin()[j] -
a1[j] - body0_trans.getOrigin()[j]);
}
}
else
{
for (int j=0; j<3; j++)
{
info->c[j] = k * (p2pconstraint->getPivotInB()[j] - a1[j] -
body0_trans.getOrigin()[j]);
}
}
}
///////////////////limit motor support
/*! \pre testLimitValue must be called on limot*/
int bt_get_limit_motor_info2(
btRotationalLimitMotor * limot,
btRigidBody * body0, btRigidBody * body1,
BU_Joint::Info2 *info, int row, btVector3& ax1, int rotational)
{
int srow = row * info->rowskip;
// if the joint is powered, or has joint limits, add in the extra row
int powered = limot->m_enableMotor;
int limit = limot->m_currentLimit;
if (powered || limit)
{
btScalar *J1 = rotational ? info->J1a : info->J1l;
btScalar *J2 = rotational ? info->J2a : info->J2l;
J1[srow+0] = ax1[0];
J1[srow+1] = ax1[1];
J1[srow+2] = ax1[2];
if (body1)
{
J2[srow+0] = -ax1[0];
J2[srow+1] = -ax1[1];
J2[srow+2] = -ax1[2];
}
// linear limot torque decoupling step:
//
// if this is a linear limot (e.g. from a slider), we have to be careful
// that the linear constraint forces (+/- ax1) applied to the two bodies
// do not create a torque couple. in other words, the points that the
// constraint force is applied at must lie along the same ax1 axis.
// a torque couple will result in powered or limited slider-jointed free
// bodies from gaining angular momentum.
// the solution used here is to apply the constraint forces at the point
// halfway between the body centers. there is no penalty (other than an
// extra tiny bit of computation) in doing this adjustment. note that we
// only need to do this if the constraint connects two bodies.
btVector3 ltd; // Linear Torque Decoupling vector (a torque)
if (!rotational && body1)
{
btVector3 c;
c[0]=btScalar(0.5)*(body1->getCenterOfMassPosition()[0]
-body0->getCenterOfMassPosition()[0]);
c[1]=btScalar(0.5)*(body1->getCenterOfMassPosition()[1]
-body0->getCenterOfMassPosition()[1]);
c[2]=btScalar(0.5)*(body1->getCenterOfMassPosition()[2]
-body0->getCenterOfMassPosition()[2]);
ltd = c.cross(ax1);
info->J1a[srow+0] = ltd[0];
info->J1a[srow+1] = ltd[1];
info->J1a[srow+2] = ltd[2];
info->J2a[srow+0] = ltd[0];
info->J2a[srow+1] = ltd[1];
info->J2a[srow+2] = ltd[2];
}
// if we're limited low and high simultaneously, the joint motor is
// ineffective
if (limit && (limot->m_loLimit == limot->m_hiLimit)) powered = 0;
if (powered)
{
info->cfm[row] = 0.0f;//limot->m_normalCFM;
if (! limit)
{
info->c[row] = limot->m_targetVelocity;
info->lo[row] = -limot->m_maxMotorForce;
info->hi[row] = limot->m_maxMotorForce;
}
}
if (limit)
{
btScalar k = info->fps * limot->m_ERP;
info->c[row] = -k * limot->m_currentLimitError;
info->cfm[row] = 0.0f;//limot->m_stopCFM;
if (limot->m_loLimit == limot->m_hiLimit)
{
// limited low and high simultaneously
info->lo[row] = -dInfinity;
info->hi[row] = dInfinity;
}
else
{
if (limit == 1)
{
// low limit
info->lo[row] = 0;
info->hi[row] = SIMD_INFINITY;
}
else
{
// high limit
info->lo[row] = -SIMD_INFINITY;
info->hi[row] = 0;
}
// deal with bounce
if (limot->m_bounce > 0)
{
// calculate joint velocity
btScalar vel;
if (rotational)
{
vel = body0->getAngularVelocity().dot(ax1);
if (body1)
vel -= body1->getAngularVelocity().dot(ax1);
}
else
{
vel = body0->getLinearVelocity().dot(ax1);
if (body1)
vel -= body1->getLinearVelocity().dot(ax1);
}
// only apply bounce if the velocity is incoming, and if the
// resulting c[] exceeds what we already have.
if (limit == 1)
{
// low limit
if (vel < 0)
{
btScalar newc = -limot->m_bounce* vel;
if (newc > info->c[row]) info->c[row] = newc;
}
}
else
{
// high limit - all those computations are reversed
if (vel > 0)
{
btScalar newc = -limot->m_bounce * vel;
if (newc < info->c[row]) info->c[row] = newc;
}
}
}
}
}
return 1;
}
else return 0;
}
///////////////////OdeD6Joint
OdeD6Joint::OdeD6Joint(
btTypedConstraint * constraint,
int index,bool swap,OdeSolverBody* body0,OdeSolverBody* body1):
OdeTypedJoint(constraint,index,swap,body0,body1)
{
}
void OdeD6Joint::GetInfo1(Info1 *info)
{
btGeneric6DofConstraint * d6constraint = this->getD6Constraint();
//prepare constraint
d6constraint->calculateTransforms();
info->m = 3;
info->nub = 3;
//test angular limits
for (int i=0;i<3 ;i++ )
{
//if(i==2) continue;
if(d6constraint->testAngularLimitMotor(i))
{
info->m++;
}
}
}
int OdeD6Joint::setLinearLimits(Info2 *info)
{
btGeneric6DofConstraint * d6constraint = this->getD6Constraint();
//retrieve matrices
btTransform body0_trans;
if (m_body0)
{
body0_trans = m_body0->m_originalBody->getCenterOfMassTransform();
}
btTransform body1_trans;
if (m_body1)
{
body1_trans = m_body1->m_originalBody->getCenterOfMassTransform();
}
// anchor points in global coordinates with respect to body PORs.
int s = info->rowskip;
// set jacobian
info->J1l[0] = 1;
info->J1l[s+1] = 1;
info->J1l[2*s+2] = 1;
btVector3 a1,a2;
a1 = body0_trans.getBasis()*d6constraint->getFrameOffsetA().getOrigin();
//dMULTIPLY0_331 (a1, body0_mat,m_constraint->m_pivotInA);
dCROSSMAT (info->J1a,a1,s,-,+);
if (m_body1)
{
info->J2l[0] = -1;
info->J2l[s+1] = -1;
info->J2l[2*s+2] = -1;
a2 = body1_trans.getBasis()*d6constraint->getFrameOffsetB().getOrigin();
//dMULTIPLY0_331 (a2,body1_mat,m_constraint->m_pivotInB);
dCROSSMAT (info->J2a,a2,s,+,-);
}
// set right hand side
btScalar k = info->fps * info->erp;
if (m_body1)
{
for (int j=0; j<3; j++)
{
info->c[j] = k * (a2[j] + body1_trans.getOrigin()[j] -
a1[j] - body0_trans.getOrigin()[j]);
}
}
else
{
for (int j=0; j<3; j++)
{
info->c[j] = k * (d6constraint->getCalculatedTransformB().getOrigin()[j] - a1[j] -
body0_trans.getOrigin()[j]);
}
}
return 3;
}
int OdeD6Joint::setAngularLimits(Info2 *info, int row_offset)
{
btGeneric6DofConstraint * d6constraint = this->getD6Constraint();
int row = row_offset;
//solve angular limits
for (int i=0;i<3 ;i++ )
{
//if(i==2) continue;
if(d6constraint->getRotationalLimitMotor(i)->needApplyTorques())
{
btVector3 axis = d6constraint->getAxis(i);
row += bt_get_limit_motor_info2(
d6constraint->getRotationalLimitMotor(i),
m_body0->m_originalBody,m_body1->m_originalBody,info,row,axis,1);
}
}
return row;
}
void OdeD6Joint::GetInfo2(Info2 *info)
{
int row = setLinearLimits(info);
setAngularLimits(info, row);
}