void
dxJointLMotor::getInfo2( dReal worldFPS, dReal worldERP, const Info2Descr *info )
{
int row = 0;
dVector3 ax[3];
computeGlobalAxes( ax );
for ( int i = 0;i < num;i++ )
{
row += limot[i].addLimot( this, worldFPS, info, row, ax[i], 0 );
}
}
void
dxJointAMotor::getInfo2( dxJoint::Info2 *info )
{
int i;
// compute the axes (if not global)
dVector3 ax[3];
computeGlobalAxes( ax );
// in euler angle mode we do not actually constrain the angular velocity
// along the axes axis[0] and axis[2] (although we do use axis[1]) :
//
// to get constrain w2-w1 along ...not
// ------ --------------------- ------
// d(angle[0])/dt = 0 ax[1] x ax[2] ax[0]
// d(angle[1])/dt = 0 ax[1]
// d(angle[2])/dt = 0 ax[0] x ax[1] ax[2]
//
// constraining w2-w1 along an axis 'a' means that a'*(w2-w1)=0.
// to prove the result for angle[0], write the expression for angle[0] from
// GetInfo1 then take the derivative. to prove this for angle[2] it is
// easier to take the euler rate expression for d(angle[2])/dt with respect
// to the components of w and set that to 0.
dVector3 *axptr[3];
axptr[0] = &ax[0];
axptr[1] = &ax[1];
axptr[2] = &ax[2];
dVector3 ax0_cross_ax1;
dVector3 ax1_cross_ax2;
if ( mode == dAMotorEuler )
{
dCalcVectorCross3( ax0_cross_ax1, ax[0], ax[1] );
axptr[2] = &ax0_cross_ax1;
dCalcVectorCross3( ax1_cross_ax2, ax[1], ax[2] );
axptr[0] = &ax1_cross_ax2;
}
int row = 0;
for ( i = 0; i < num; i++ )
{
row += limot[i].addLimot( this, info, row, *( axptr[i] ), 1 );
}
}
void
dxJointAMotor::getInfo1( dxJoint::Info1 *info )
{
info->m = 0;
info->nub = 0;
// compute the axes and angles, if in Euler mode
if ( mode == dAMotorEuler )
{
dVector3 ax[3];
computeGlobalAxes( ax );
computeEulerAngles( ax );
}
// see if we're powered or at a joint limit for each axis
for ( int i = 0; i < num; i++ )
{
if ( limot[i].testRotationalLimit( angle[i] ) ||
limot[i].fmax > 0 )
{
info->m++;
}
}
}
