public override bool solvePositionConstraints(SolverData data)
{
if (m_frequencyHz > 0.0d)
{
return(true);
}
Rot qA = pool.popRot();
Rot qB = pool.popRot();
Vec2 rA = pool.popVec2();
Vec2 rB = pool.popVec2();
Vec2 u = pool.popVec2();
Vec2 cA = data.positions[m_indexA].c;
double aA = data.positions[m_indexA].a;
Vec2 cB = data.positions[m_indexB].c;
double aB = data.positions[m_indexB].a;
qA.set(aA);
qB.set(aB);
Rot.mulToOutUnsafe(qA, u.set(m_localAnchorA).subLocal(m_localCenterA), rA);
Rot.mulToOutUnsafe(qB, u.set(m_localAnchorB).subLocal(m_localCenterB), rB);
u.set(cB).addLocal(rB).subLocal(cA).subLocal(rA);
double length = u.normalize();
double C = length - m_length;
C = MathUtils.clamp(C, -Settings.maxLinearCorrection, Settings.maxLinearCorrection);
double impulse = -m_mass * C;
double Px = impulse * u.x;
double Py = impulse * u.y;
cA.x -= m_invMassA * Px;
cA.y -= m_invMassA * Py;
aA -= m_invIA * (rA.x * Py - rA.y * Px);
cB.x += m_invMassB * Px;
cB.y += m_invMassB * Py;
aB += m_invIB * (rB.x * Py - rB.y * Px);
// data.positions[m_indexA].c.set(cA);
data.positions[m_indexA].a = aA;
// data.positions[m_indexB].c.set(cB);
data.positions[m_indexB].a = aB;
pool.pushVec2(3);
pool.pushRot(2);
return(MathUtils.abs(C) < Settings.linearSlop);
}
public override bool solvePositionConstraints(SolverData data)
{
Vec2 cA = data.positions[m_indexA].c;
double aA = data.positions[m_indexA].a;
Vec2 cB = data.positions[m_indexB].c;
double aB = data.positions[m_indexB].a;
Rot qA = pool.popRot();
Rot qB = pool.popRot();
Vec2 u = pool.popVec2();
Vec2 rA = pool.popVec2();
Vec2 rB = pool.popVec2();
Vec2 temp = pool.popVec2();
qA.set(aA);
qB.set(aB);
// Compute the effective masses.
Rot.mulToOutUnsafe(qA, temp.set(m_localAnchorA).subLocal(m_localCenterA), rA);
Rot.mulToOutUnsafe(qB, temp.set(m_localAnchorB).subLocal(m_localCenterB), rB);
u.set(cB).addLocal(rB).subLocal(cA).subLocal(rA);
double length = u.normalize();
double C = length - m_maxLength;
C = MathUtils.clamp(C, 0.0d, Settings.maxLinearCorrection);
double impulse = -m_mass * C;
double Px = impulse * u.x;
double Py = impulse * u.y;
cA.x -= m_invMassA * Px;
cA.y -= m_invMassA * Py;
aA -= m_invIA * (rA.x * Py - rA.y * Px);
cB.x += m_invMassB * Px;
cB.y += m_invMassB * Py;
aB += m_invIB * (rB.x * Py - rB.y * Px);
pool.pushRot(2);
pool.pushVec2(4);
// data.positions[m_indexA].c = cA;
data.positions[m_indexA].a = aA;
// data.positions[m_indexB].c = cB;
data.positions[m_indexB].a = aB;
return(length - m_maxLength < Settings.linearSlop);
}
/** Set this to equal another transform. */
public Transform set(Transform xf)
{
p.set(xf.p);
q.set(xf.q);
return(this);
}
/**
* @see org.jbox2d.dynamics.joints.Joint#initVelocityConstraints(org.jbox2d.dynamics.TimeStep)
*/
public override void initVelocityConstraints(SolverData data)
{
m_indexA = m_bodyA.m_islandIndex;
m_indexB = m_bodyB.m_islandIndex;
m_localCenterA.set(m_bodyA.m_sweep.localCenter);
m_localCenterB.set(m_bodyB.m_sweep.localCenter);
m_invMassA = m_bodyA.m_invMass;
m_invMassB = m_bodyB.m_invMass;
m_invIA = m_bodyA.m_invI;
m_invIB = m_bodyB.m_invI;
double aA = data.positions[m_indexA].a;
Vec2 vA = data.velocities[m_indexA].v;
double wA = data.velocities[m_indexA].w;
double aB = data.positions[m_indexB].a;
Vec2 vB = data.velocities[m_indexB].v;
double wB = data.velocities[m_indexB].w;
Vec2 temp = pool.popVec2();
Rot qA = pool.popRot();
Rot qB = pool.popRot();
qA.set(aA);
qB.set(aB);
// Compute the effective mass matrix.
Rot.mulToOutUnsafe(qA, temp.set(m_localAnchorA).subLocal(m_localCenterA), m_rA);
Rot.mulToOutUnsafe(qB, temp.set(m_localAnchorB).subLocal(m_localCenterB), m_rB);
// J = [-I -r1_skew I r2_skew]
// [ 0 -1 0 1]
// r_skew = [-ry; rx]
// Matlab
// K = [ mA+r1y^2*iA+mB+r2y^2*iB, -r1y*iA*r1x-r2y*iB*r2x, -r1y*iA-r2y*iB]
// [ -r1y*iA*r1x-r2y*iB*r2x, mA+r1x^2*iA+mB+r2x^2*iB, r1x*iA+r2x*iB]
// [ -r1y*iA-r2y*iB, r1x*iA+r2x*iB, iA+iB]
double mA = m_invMassA, mB = m_invMassB;
double iA = m_invIA, iB = m_invIB;
Mat22 K = pool.popMat22();
K.ex.x = mA + mB + iA * m_rA.y * m_rA.y + iB * m_rB.y * m_rB.y;
K.ex.y = -iA * m_rA.x * m_rA.y - iB * m_rB.x * m_rB.y;
K.ey.x = K.ex.y;
K.ey.y = mA + mB + iA * m_rA.x * m_rA.x + iB * m_rB.x * m_rB.x;
K.invertToOut(m_linearMass);
m_angularMass = iA + iB;
if (m_angularMass > 0.0d)
{
m_angularMass = 1.0d / m_angularMass;
}
if (data.step.warmStarting)
{
// Scale impulses to support a variable time step.
m_linearImpulse.mulLocal(data.step.dtRatio);
m_angularImpulse *= data.step.dtRatio;
Vec2 P = pool.popVec2();
P.set(m_linearImpulse);
temp.set(P).mulLocal(mA);
vA.subLocal(temp);
wA -= iA * (Vec2.cross(m_rA, P) + m_angularImpulse);
temp.set(P).mulLocal(mB);
vB.addLocal(temp);
wB += iB * (Vec2.cross(m_rB, P) + m_angularImpulse);
pool.pushVec2(1);
}
else
{
m_linearImpulse.setZero();
m_angularImpulse = 0.0d;
}
// data.velocities[m_indexA].v.set(vA);
if (data.velocities[m_indexA].w != wA)
{
}
data.velocities[m_indexA].w = wA;
// data.velocities[m_indexB].v.set(vB);
data.velocities[m_indexB].w = wB;
pool.pushRot(2);
pool.pushVec2(1);
pool.pushMat22(1);
}
public override bool solvePositionConstraints(SolverData data)
{
Rot qA = pool.popRot();
Rot qB = pool.popRot();
Vec2 cA = data.positions[m_indexA].c;
double aA = data.positions[m_indexA].a;
Vec2 cB = data.positions[m_indexB].c;
double aB = data.positions[m_indexB].a;
qA.set(aA);
qB.set(aB);
double angularError = 0.0d;
double positionError = 0.0d;
bool fixedRotation = (m_invIA + m_invIB == 0.0d);
// Solve angular limit constraint.
if (m_enableLimit && m_limitState != LimitState.INACTIVE && fixedRotation == false)
{
double angle = aB - aA - m_referenceAngle;
double limitImpulse = 0.0d;
if (m_limitState == LimitState.EQUAL)
{
// Prevent large angular corrections
double C =
MathUtils.clamp(angle - m_lowerAngle, -Settings.maxAngularCorrection,
Settings.maxAngularCorrection);
limitImpulse = -m_motorMass * C;
angularError = MathUtils.abs(C);
}
else if (m_limitState == LimitState.AT_LOWER)
{
double C = angle - m_lowerAngle;
angularError = -C;
// Prevent large angular corrections and allow some slop.
C = MathUtils.clamp(C + Settings.angularSlop, -Settings.maxAngularCorrection, 0.0d);
limitImpulse = -m_motorMass * C;
}
else if (m_limitState == LimitState.AT_UPPER)
{
double C = angle - m_upperAngle;
angularError = C;
// Prevent large angular corrections and allow some slop.
C = MathUtils.clamp(C - Settings.angularSlop, 0.0d, Settings.maxAngularCorrection);
limitImpulse = -m_motorMass * C;
}
aA -= m_invIA * limitImpulse;
aB += m_invIB * limitImpulse;
}
// Solve point-to-point constraint.
{
qA.set(aA);
qB.set(aB);
Vec2 rA = pool.popVec2();
Vec2 rB = pool.popVec2();
Vec2 C = pool.popVec2();
Vec2 impulse = pool.popVec2();
Rot.mulToOutUnsafe(qA, C.set(m_localAnchorA).subLocal(m_localCenterA), rA);
Rot.mulToOutUnsafe(qB, C.set(m_localAnchorB).subLocal(m_localCenterB), rB);
C.set(cB).addLocal(rB).subLocal(cA).subLocal(rA);
positionError = C.length();
double mA = m_invMassA, mB = m_invMassB;
double iA = m_invIA, iB = m_invIB;
Mat22 K = pool.popMat22();
K.ex.x = mA + mB + iA * rA.y * rA.y + iB * rB.y * rB.y;
K.ex.y = -iA * rA.x * rA.y - iB * rB.x * rB.y;
K.ey.x = K.ex.y;
K.ey.y = mA + mB + iA * rA.x * rA.x + iB * rB.x * rB.x;
K.solveToOut(C, impulse);
impulse.negateLocal();
cA.x -= mA * impulse.x;
cA.y -= mA * impulse.y;
aA -= iA * Vec2.cross(rA, impulse);
cB.x += mB * impulse.x;
cB.y += mB * impulse.y;
aB += iB * Vec2.cross(rB, impulse);
pool.pushVec2(4);
pool.pushMat22(1);
}
// data.positions[m_indexA].c.set(cA);
data.positions[m_indexA].a = aA;
// data.positions[m_indexB].c.set(cB);
data.positions[m_indexB].a = aB;
pool.pushRot(2);
return(positionError <= Settings.linearSlop && angularError <= Settings.angularSlop);
}
public override void initVelocityConstraints(SolverData data)
{
m_indexA = m_bodyA.m_islandIndex;
m_indexB = m_bodyB.m_islandIndex;
m_localCenterA.set(m_bodyA.m_sweep.localCenter);
m_localCenterB.set(m_bodyB.m_sweep.localCenter);
m_invMassA = m_bodyA.m_invMass;
m_invMassB = m_bodyB.m_invMass;
m_invIA = m_bodyA.m_invI;
m_invIB = m_bodyB.m_invI;
// Vec2 cA = data.positions[m_indexA].c;
double aA = data.positions[m_indexA].a;
Vec2 vA = data.velocities[m_indexA].v;
double wA = data.velocities[m_indexA].w;
// Vec2 cB = data.positions[m_indexB].c;
double aB = data.positions[m_indexB].a;
Vec2 vB = data.velocities[m_indexB].v;
double wB = data.velocities[m_indexB].w;
Rot qA = pool.popRot();
Rot qB = pool.popRot();
Vec2 temp = pool.popVec2();
qA.set(aA);
qB.set(aB);
// Compute the effective masses.
Rot.mulToOutUnsafe(qA, temp.set(m_localAnchorA).subLocal(m_localCenterA), m_rA);
Rot.mulToOutUnsafe(qB, temp.set(m_localAnchorB).subLocal(m_localCenterB), m_rB);
// J = [-I -r1_skew I r2_skew]
// [ 0 -1 0 1]
// r_skew = [-ry; rx]
// Matlab
// K = [ mA+r1y^2*iA+mB+r2y^2*iB, -r1y*iA*r1x-r2y*iB*r2x, -r1y*iA-r2y*iB]
// [ -r1y*iA*r1x-r2y*iB*r2x, mA+r1x^2*iA+mB+r2x^2*iB, r1x*iA+r2x*iB]
// [ -r1y*iA-r2y*iB, r1x*iA+r2x*iB, iA+iB]
double mA = m_invMassA, mB = m_invMassB;
double iA = m_invIA, iB = m_invIB;
bool fixedRotation = (iA + iB == 0.0d);
m_mass.ex.x = mA + mB + m_rA.y * m_rA.y * iA + m_rB.y * m_rB.y * iB;
m_mass.ey.x = -m_rA.y * m_rA.x * iA - m_rB.y * m_rB.x * iB;
m_mass.ez.x = -m_rA.y * iA - m_rB.y * iB;
m_mass.ex.y = m_mass.ey.x;
m_mass.ey.y = mA + mB + m_rA.x * m_rA.x * iA + m_rB.x * m_rB.x * iB;
m_mass.ez.y = m_rA.x * iA + m_rB.x * iB;
m_mass.ex.z = m_mass.ez.x;
m_mass.ey.z = m_mass.ez.y;
m_mass.ez.z = iA + iB;
m_motorMass = iA + iB;
if (m_motorMass > 0.0d)
{
m_motorMass = 1.0d / m_motorMass;
}
if (m_enableMotor == false || fixedRotation)
{
m_motorImpulse = 0.0d;
}
if (m_enableLimit && fixedRotation == false)
{
double jointAngle = aB - aA - m_referenceAngle;
if (MathUtils.abs(m_upperAngle - m_lowerAngle) < 2.0d * Settings.angularSlop)
{
m_limitState = LimitState.EQUAL;
}
else if (jointAngle <= m_lowerAngle)
{
if (m_limitState != LimitState.AT_LOWER)
{
m_impulse.z = 0.0d;
}
m_limitState = LimitState.AT_LOWER;
}
else if (jointAngle >= m_upperAngle)
{
if (m_limitState != LimitState.AT_UPPER)
{
m_impulse.z = 0.0d;
}
m_limitState = LimitState.AT_UPPER;
}
else
{
m_limitState = LimitState.INACTIVE;
m_impulse.z = 0.0d;
}
}
else
{
m_limitState = LimitState.INACTIVE;
}
if (data.step.warmStarting)
{
Vec2 P = pool.popVec2();
// Scale impulses to support a variable time step.
m_impulse.x *= data.step.dtRatio;
m_impulse.y *= data.step.dtRatio;
m_motorImpulse *= data.step.dtRatio;
P.x = m_impulse.x;
P.y = m_impulse.y;
vA.x -= mA * P.x;
vA.y -= mA * P.y;
wA -= iA * (Vec2.cross(m_rA, P) + m_motorImpulse + m_impulse.z);
vB.x += mB * P.x;
vB.y += mB * P.y;
wB += iB * (Vec2.cross(m_rB, P) + m_motorImpulse + m_impulse.z);
pool.pushVec2(1);
}
else
{
m_impulse.setZero();
m_motorImpulse = 0.0d;
}
// data.velocities[m_indexA].v.set(vA);
data.velocities[m_indexA].w = wA;
// data.velocities[m_indexB].v.set(vB);
data.velocities[m_indexB].w = wB;
pool.pushVec2(1);
pool.pushRot(2);
}
public override bool solvePositionConstraints(SolverData data)
{
Vec2 cA = data.positions[m_indexA].c;
double aA = data.positions[m_indexA].a;
Vec2 cB = data.positions[m_indexB].c;
double aB = data.positions[m_indexB].a;
Vec2 cC = data.positions[m_indexC].c;
double aC = data.positions[m_indexC].a;
Vec2 cD = data.positions[m_indexD].c;
double aD = data.positions[m_indexD].a;
Rot qA = pool.popRot(), qB = pool.popRot(), qC = pool.popRot(), qD = pool.popRot();
qA.set(aA);
qB.set(aB);
qC.set(aC);
qD.set(aD);
double linearError = 0.0d;
double coordinateA, coordinateB;
Vec2 temp = pool.popVec2();
Vec2 JvAC = pool.popVec2();
Vec2 JvBD = pool.popVec2();
double JwA, JwB, JwC, JwD;
double mass = 0.0d;
if (m_typeA == JointType.REVOLUTE)
{
JvAC.setZero();
JwA = 1.0d;
JwC = 1.0d;
mass += m_iA + m_iC;
coordinateA = aA - aC - m_referenceAngleA;
}
else
{
Vec2 rC = pool.popVec2();
Vec2 rA = pool.popVec2();
Vec2 pC = pool.popVec2();
Vec2 pA = pool.popVec2();
Rot.mulToOutUnsafe(qC, m_localAxisC, JvAC);
Rot.mulToOutUnsafe(qC, temp.set(m_localAnchorC).subLocal(m_lcC), rC);
Rot.mulToOutUnsafe(qA, temp.set(m_localAnchorA).subLocal(m_lcA), rA);
JwC = Vec2.cross(rC, JvAC);
JwA = Vec2.cross(rA, JvAC);
mass += m_mC + m_mA + m_iC * JwC * JwC + m_iA * JwA * JwA;
pC.set(m_localAnchorC).subLocal(m_lcC);
Rot.mulTransUnsafe(qC, temp.set(rA).addLocal(cA).subLocal(cC), pA);
coordinateA = Vec2.dot(pA.subLocal(pC), m_localAxisC);
pool.pushVec2(4);
}
if (m_typeB == JointType.REVOLUTE)
{
JvBD.setZero();
JwB = m_ratio;
JwD = m_ratio;
mass += m_ratio * m_ratio * (m_iB + m_iD);
coordinateB = aB - aD - m_referenceAngleB;
}
else
{
Vec2 u = pool.popVec2();
Vec2 rD = pool.popVec2();
Vec2 rB = pool.popVec2();
Vec2 pD = pool.popVec2();
Vec2 pB = pool.popVec2();
Rot.mulToOutUnsafe(qD, m_localAxisD, u);
Rot.mulToOutUnsafe(qD, temp.set(m_localAnchorD).subLocal(m_lcD), rD);
Rot.mulToOutUnsafe(qB, temp.set(m_localAnchorB).subLocal(m_lcB), rB);
JvBD.set(u).mulLocal(m_ratio);
JwD = Vec2.cross(rD, u);
JwB = Vec2.cross(rB, u);
mass += m_ratio * m_ratio * (m_mD + m_mB) + m_iD * JwD * JwD + m_iB * JwB * JwB;
pD.set(m_localAnchorD).subLocal(m_lcD);
Rot.mulTransUnsafe(qD, temp.set(rB).addLocal(cB).subLocal(cD), pB);
coordinateB = Vec2.dot(pB.subLocal(pD), m_localAxisD);
pool.pushVec2(5);
}
double C = (coordinateA + m_ratio * coordinateB) - m_constant;
double impulse = 0.0d;
if (mass > 0.0d)
{
impulse = -C / mass;
}
pool.pushVec2(3);
pool.pushRot(4);
cA.x += (m_mA * impulse) * JvAC.x;
cA.y += (m_mA * impulse) * JvAC.y;
aA += m_iA * impulse * JwA;
cB.x += (m_mB * impulse) * JvBD.x;
cB.y += (m_mB * impulse) * JvBD.y;
aB += m_iB * impulse * JwB;
cC.x -= (m_mC * impulse) * JvAC.x;
cC.y -= (m_mC * impulse) * JvAC.y;
aC -= m_iC * impulse * JwC;
cD.x -= (m_mD * impulse) * JvBD.x;
cD.y -= (m_mD * impulse) * JvBD.y;
aD -= m_iD * impulse * JwD;
// data.positions[m_indexA].c = cA;
data.positions[m_indexA].a = aA;
// data.positions[m_indexB].c = cB;
data.positions[m_indexB].a = aB;
// data.positions[m_indexC].c = cC;
data.positions[m_indexC].a = aC;
// data.positions[m_indexD].c = cD;
data.positions[m_indexD].a = aD;
// TODO_ERIN not implemented
return(linearError < Settings.linearSlop);
}
public override void initVelocityConstraints(SolverData data)
{
m_indexA = m_bodyA.m_islandIndex;
m_indexB = m_bodyB.m_islandIndex;
m_localCenterA.set(m_bodyA.m_sweep.localCenter);
m_localCenterB.set(m_bodyB.m_sweep.localCenter);
m_invMassA = m_bodyA.m_invMass;
m_invMassB = m_bodyB.m_invMass;
m_invIA = m_bodyA.m_invI;
m_invIB = m_bodyB.m_invI;
Vec2 cA = data.positions[m_indexA].c;
double aA = data.positions[m_indexA].a;
Vec2 vA = data.velocities[m_indexA].v;
double wA = data.velocities[m_indexA].w;
Vec2 cB = data.positions[m_indexB].c;
double aB = data.positions[m_indexB].a;
Vec2 vB = data.velocities[m_indexB].v;
double wB = data.velocities[m_indexB].w;
Rot qA = pool.popRot();
Rot qB = pool.popRot();
Vec2 temp = pool.popVec2();
qA.set(aA);
qB.set(aB);
// Compute the effective masses.
Rot.mulToOutUnsafe(qA, temp.set(m_localAnchorA).subLocal(m_localCenterA), m_rA);
Rot.mulToOutUnsafe(qB, temp.set(m_localAnchorB).subLocal(m_localCenterB), m_rB);
m_uA.set(cA).addLocal(m_rA).subLocal(m_groundAnchorA);
m_uB.set(cB).addLocal(m_rB).subLocal(m_groundAnchorB);
double lengthA = m_uA.length();
double lengthB = m_uB.length();
if (lengthA > 10d * Settings.linearSlop)
{
m_uA.mulLocal(1.0d / lengthA);
}
else
{
m_uA.setZero();
}
if (lengthB > 10d * Settings.linearSlop)
{
m_uB.mulLocal(1.0d / lengthB);
}
else
{
m_uB.setZero();
}
// Compute effective mass.
double ruA = Vec2.cross(m_rA, m_uA);
double ruB = Vec2.cross(m_rB, m_uB);
double mA = m_invMassA + m_invIA * ruA * ruA;
double mB = m_invMassB + m_invIB * ruB * ruB;
m_mass = mA + m_ratio * m_ratio * mB;
if (m_mass > 0.0d)
{
m_mass = 1.0d / m_mass;
}
if (data.step.warmStarting)
{
// Scale impulses to support variable time steps.
m_impulse *= data.step.dtRatio;
// Warm starting.
Vec2 PA = pool.popVec2();
Vec2 PB = pool.popVec2();
PA.set(m_uA).mulLocal(-m_impulse);
PB.set(m_uB).mulLocal(-m_ratio * m_impulse);
vA.x += m_invMassA * PA.x;
vA.y += m_invMassA * PA.y;
wA += m_invIA * Vec2.cross(m_rA, PA);
vB.x += m_invMassB * PB.x;
vB.y += m_invMassB * PB.y;
wB += m_invIB * Vec2.cross(m_rB, PB);
pool.pushVec2(2);
}
else
{
m_impulse = 0.0d;
}
// data.velocities[m_indexA].v.set(vA);
data.velocities[m_indexA].w = wA;
// data.velocities[m_indexB].v.set(vB);
data.velocities[m_indexB].w = wB;
pool.pushVec2(1);
pool.pushRot(2);
}
// pooling
public override void initVelocityConstraints(SolverData data)
{
m_indexA = m_bodyA.m_islandIndex;
m_indexB = m_bodyB.m_islandIndex;
m_localCenterA.set(m_bodyA.m_sweep.localCenter);
m_localCenterB.set(m_bodyB.m_sweep.localCenter);
m_invMassA = m_bodyA.m_invMass;
m_invMassB = m_bodyB.m_invMass;
m_invIA = m_bodyA.m_invI;
m_invIB = m_bodyB.m_invI;
double mA = m_invMassA, mB = m_invMassB;
double iA = m_invIA, iB = m_invIB;
Vec2 cA = data.positions[m_indexA].c;
double aA = data.positions[m_indexA].a;
Vec2 vA = data.velocities[m_indexA].v;
double wA = data.velocities[m_indexA].w;
Vec2 cB = data.positions[m_indexB].c;
double aB = data.positions[m_indexB].a;
Vec2 vB = data.velocities[m_indexB].v;
double wB = data.velocities[m_indexB].w;
Rot qA = pool.popRot();
Rot qB = pool.popRot();
Vec2 temp = pool.popVec2();
qA.set(aA);
qB.set(aB);
// Compute the effective masses.
Rot.mulToOutUnsafe(qA, temp.set(m_localAnchorA).subLocal(m_localCenterA), rA);
Rot.mulToOutUnsafe(qB, temp.set(m_localAnchorB).subLocal(m_localCenterB), rB);
d2.set(cB).addLocal(rB).subLocal(cA).subLocal(rA);
// Point to line constraint
{
Rot.mulToOut(qA, m_localYAxisA, m_ay);
m_sAy = Vec2.cross(temp.set(d2).addLocal(rA), m_ay);
m_sBy = Vec2.cross(rB, m_ay);
m_mass = mA + mB + iA * m_sAy * m_sAy + iB * m_sBy * m_sBy;
if (m_mass > 0.0d)
{
m_mass = 1.0d / m_mass;
}
}
// Spring constraint
m_springMass = 0.0d;
m_bias = 0.0d;
m_gamma = 0.0d;
if (m_frequencyHz > 0.0d)
{
Rot.mulToOut(qA, m_localXAxisA, m_ax);
m_sAx = Vec2.cross(temp.set(d2).addLocal(rA), m_ax);
m_sBx = Vec2.cross(rB, m_ax);
double invMass = mA + mB + iA * m_sAx * m_sAx + iB * m_sBx * m_sBx;
if (invMass > 0.0d)
{
m_springMass = 1.0d / invMass;
double C = Vec2.dot(d2, m_ax);
// Frequency
double omega = 2.0d * MathUtils.PI * m_frequencyHz;
// Damping coefficient
double d = 2.0d * m_springMass * m_dampingRatio * omega;
// Spring stiffness
double k = m_springMass * omega * omega;
// magic formulas
double h = data.step.dt;
m_gamma = h * (d + h * k);
if (m_gamma > 0.0d)
{
m_gamma = 1.0d / m_gamma;
}
m_bias = C * h * k * m_gamma;
m_springMass = invMass + m_gamma;
if (m_springMass > 0.0d)
{
m_springMass = 1.0d / m_springMass;
}
}
}
else
{
m_springImpulse = 0.0d;
}
// Rotational motor
if (m_enableMotor)
{
m_motorMass = iA + iB;
if (m_motorMass > 0.0d)
{
m_motorMass = 1.0d / m_motorMass;
}
}
else
{
m_motorMass = 0.0d;
m_motorImpulse = 0.0d;
}
if (data.step.warmStarting)
{
Vec2 P = pool.popVec2();
// Account for variable time step.
m_impulse *= data.step.dtRatio;
m_springImpulse *= data.step.dtRatio;
m_motorImpulse *= data.step.dtRatio;
P.x = m_impulse * m_ay.x + m_springImpulse * m_ax.x;
P.y = m_impulse * m_ay.y + m_springImpulse * m_ax.y;
double LA = m_impulse * m_sAy + m_springImpulse * m_sAx + m_motorImpulse;
double LB = m_impulse * m_sBy + m_springImpulse * m_sBx + m_motorImpulse;
vA.x -= m_invMassA * P.x;
vA.y -= m_invMassA * P.y;
wA -= m_invIA * LA;
vB.x += m_invMassB * P.x;
vB.y += m_invMassB * P.y;
wB += m_invIB * LB;
pool.pushVec2(1);
}
else
{
m_impulse = 0.0d;
m_springImpulse = 0.0d;
m_motorImpulse = 0.0d;
}
pool.pushRot(2);
pool.pushVec2(1);
// data.velocities[m_indexA].v = vA;
data.velocities[m_indexA].w = wA;
// data.velocities[m_indexB].v = vB;
data.velocities[m_indexB].w = wB;
}
public override bool solvePositionConstraints(SolverData data)
{
Vec2 cA = data.positions[m_indexA].c;
double aA = data.positions[m_indexA].a;
Vec2 cB = data.positions[m_indexB].c;
double aB = data.positions[m_indexB].a;
Rot qA = pool.popRot();
Rot qB = pool.popRot();
Vec2 temp = pool.popVec2();
qA.set(aA);
qB.set(aB);
Rot.mulToOut(qA, temp.set(m_localAnchorA).subLocal(m_localCenterA), rA);
Rot.mulToOut(qB, temp.set(m_localAnchorB).subLocal(m_localCenterB), rB);
d2.set(cB).subLocal(cA).addLocal(rB).subLocal(rA);
Vec2 ay = pool.popVec2();
Rot.mulToOut(qA, m_localYAxisA, ay);
double sAy = Vec2.cross(temp.set(d2).addLocal(rA), ay);
double sBy = Vec2.cross(rB, ay);
double C = Vec2.dot(d2, ay);
double k = m_invMassA + m_invMassB + m_invIA * m_sAy * m_sAy + m_invIB * m_sBy * m_sBy;
double impulse;
if (k != 0.0d)
{
impulse = -C / k;
}
else
{
impulse = 0.0d;
}
Vec2 P = pool.popVec2();
P.x = impulse * ay.x;
P.y = impulse * ay.y;
double LA = impulse * sAy;
double LB = impulse * sBy;
cA.x -= m_invMassA * P.x;
cA.y -= m_invMassA * P.y;
aA -= m_invIA * LA;
cB.x += m_invMassB * P.x;
cB.y += m_invMassB * P.y;
aB += m_invIB * LB;
pool.pushVec2(3);
pool.pushRot(2);
// data.positions[m_indexA].c = cA;
data.positions[m_indexA].a = aA;
// data.positions[m_indexB].c = cB;
data.positions[m_indexB].a = aB;
return(MathUtils.abs(C) <= Settings.linearSlop);
}
public override void initVelocityConstraints(SolverData data)
{
m_indexB = m_bodyB.m_islandIndex;
m_localCenterB.set(m_bodyB.m_sweep.localCenter);
m_invMassB = m_bodyB.m_invMass;
m_invIB = m_bodyB.m_invI;
Vec2 cB = data.positions[m_indexB].c;
double aB = data.positions[m_indexB].a;
Vec2 vB = data.velocities[m_indexB].v;
double wB = data.velocities[m_indexB].w;
Rot qB = pool.popRot();
qB.set(aB);
double mass = m_bodyB.getMass();
// Frequency
double omega = 2.0d * MathUtils.PI * m_frequencyHz;
// Damping coefficient
double d = 2.0d * mass * m_dampingRatio * omega;
// Spring stiffness
double k = mass * (omega * omega);
// magic formulas
// gamma has units of inverse mass.
// beta has units of inverse time.
double h = data.step.dt;
m_gamma = h * (d + h * k);
if (m_gamma != 0.0d)
{
m_gamma = 1.0d / m_gamma;
}
m_beta = h * k * m_gamma;
Vec2 temp = pool.popVec2();
// Compute the effective mass matrix.
Rot.mulToOutUnsafe(qB, temp.set(m_localAnchorB).subLocal(m_localCenterB), m_rB);
// K = [(1/m1 + 1/m2) * eye(2) - skew(r1) * invI1 * skew(r1) - skew(r2) * invI2 * skew(r2)]
// = [1/m1+1/m2 0 ] + invI1 * [r1.y*r1.y -r1.x*r1.y] + invI2 * [r1.y*r1.y -r1.x*r1.y]
// [ 0 1/m1+1/m2] [-r1.x*r1.y r1.x*r1.x] [-r1.x*r1.y r1.x*r1.x]
Mat22 K = pool.popMat22();
K.ex.x = m_invMassB + m_invIB * m_rB.y * m_rB.y + m_gamma;
K.ex.y = -m_invIB * m_rB.x * m_rB.y;
K.ey.x = K.ex.y;
K.ey.y = m_invMassB + m_invIB * m_rB.x * m_rB.x + m_gamma;
K.invertToOut(m_mass);
m_C.set(cB).addLocal(m_rB).subLocal(m_targetA);
m_C.mulLocal(m_beta);
// Cheat with some damping
wB *= 0.98d;
if (data.step.warmStarting)
{
m_impulse.mulLocal(data.step.dtRatio);
vB.x += m_invMassB * m_impulse.x;
vB.y += m_invMassB * m_impulse.y;
wB += m_invIB * Vec2.cross(m_rB, m_impulse);
}
else
{
m_impulse.setZero();
}
// data.velocities[m_indexB].v.set(vB);
data.velocities[m_indexB].w = wB;
pool.pushVec2(1);
pool.pushMat22(1);
pool.pushRot(1);
}
public override bool solvePositionConstraints(SolverData data)
{
Vec2 cA = data.positions[m_indexA].c;
double aA = data.positions[m_indexA].a;
Vec2 cB = data.positions[m_indexB].c;
double aB = data.positions[m_indexB].a;
Rot qA = pool.popRot();
Rot qB = pool.popRot();
Vec2 temp = pool.popVec2();
Vec2 rA = pool.popVec2();
Vec2 rB = pool.popVec2();
qA.set(aA);
qB.set(aB);
double mA = m_invMassA, mB = m_invMassB;
double iA = m_invIA, iB = m_invIB;
Rot.mulToOutUnsafe(qA, temp.set(m_localAnchorA).subLocal(m_localCenterA), rA);
Rot.mulToOutUnsafe(qB, temp.set(m_localAnchorB).subLocal(m_localCenterB), rB);
double positionError, angularError;
Mat33 K = pool.popMat33();
Vec2 C1 = pool.popVec2();
Vec2 P = pool.popVec2();
K.ex.x = mA + mB + rA.y * rA.y * iA + rB.y * rB.y * iB;
K.ey.x = -rA.y * rA.x * iA - rB.y * rB.x * iB;
K.ez.x = -rA.y * iA - rB.y * iB;
K.ex.y = K.ey.x;
K.ey.y = mA + mB + rA.x * rA.x * iA + rB.x * rB.x * iB;
K.ez.y = rA.x * iA + rB.x * iB;
K.ex.z = K.ez.x;
K.ey.z = K.ez.y;
K.ez.z = iA + iB;
if (m_frequencyHz > 0.0d)
{
C1.set(cB).addLocal(rB).subLocal(cA).subLocal(rA);
positionError = C1.length();
angularError = 0.0d;
K.solve22ToOut(C1, P);
P.negateLocal();
cA.x -= mA * P.x;
cA.y -= mA * P.y;
aA -= iA * Vec2.cross(rA, P);
cB.x += mB * P.x;
cB.y += mB * P.y;
aB += iB * Vec2.cross(rB, P);
}
else
{
C1.set(cB).addLocal(rB).subLocal(cA).subLocal(rA);
double C2 = aB - aA - m_referenceAngle;
positionError = C1.length();
angularError = MathUtils.abs(C2);
Vec3 C = pool.popVec3();
Vec3 impulse = pool.popVec3();
C.set(C1.x, C1.y, C2);
K.solve33ToOut(C, impulse);
impulse.negateLocal();
P.set(impulse.x, impulse.y);
cA.x -= mA * P.x;
cA.y -= mA * P.y;
aA -= iA * (Vec2.cross(rA, P) + impulse.z);
cB.x += mB * P.x;
cB.y += mB * P.y;
aB += iB * (Vec2.cross(rB, P) + impulse.z);
pool.pushVec3(2);
}
// data.positions[m_indexA].c.set(cA);
data.positions[m_indexA].a = aA;
// data.positions[m_indexB].c.set(cB);
data.positions[m_indexB].a = aB;
pool.pushVec2(5);
pool.pushRot(2);
pool.pushMat33(1);
return(positionError <= Settings.linearSlop && angularError <= Settings.angularSlop);
}
public override void initVelocityConstraints(SolverData data)
{
m_indexA = m_bodyA.m_islandIndex;
m_indexB = m_bodyB.m_islandIndex;
m_localCenterA.set(m_bodyA.m_sweep.localCenter);
m_localCenterB.set(m_bodyB.m_sweep.localCenter);
m_invMassA = m_bodyA.m_invMass;
m_invMassB = m_bodyB.m_invMass;
m_invIA = m_bodyA.m_invI;
m_invIB = m_bodyB.m_invI;
// Vec2 cA = data.positions[m_indexA].c;
double aA = data.positions[m_indexA].a;
Vec2 vA = data.velocities[m_indexA].v;
double wA = data.velocities[m_indexA].w;
// Vec2 cB = data.positions[m_indexB].c;
double aB = data.positions[m_indexB].a;
Vec2 vB = data.velocities[m_indexB].v;
double wB = data.velocities[m_indexB].w;
Rot qA = pool.popRot();
Rot qB = pool.popRot();
Vec2 temp = pool.popVec2();
qA.set(aA);
qB.set(aB);
// Compute the effective masses.
Rot.mulToOutUnsafe(qA, temp.set(m_localAnchorA).subLocal(m_localCenterA), m_rA);
Rot.mulToOutUnsafe(qB, temp.set(m_localAnchorB).subLocal(m_localCenterB), m_rB);
// J = [-I -r1_skew I r2_skew]
// [ 0 -1 0 1]
// r_skew = [-ry; rx]
// Matlab
// K = [ mA+r1y^2*iA+mB+r2y^2*iB, -r1y*iA*r1x-r2y*iB*r2x, -r1y*iA-r2y*iB]
// [ -r1y*iA*r1x-r2y*iB*r2x, mA+r1x^2*iA+mB+r2x^2*iB, r1x*iA+r2x*iB]
// [ -r1y*iA-r2y*iB, r1x*iA+r2x*iB, iA+iB]
double mA = m_invMassA, mB = m_invMassB;
double iA = m_invIA, iB = m_invIB;
Mat33 K = pool.popMat33();
K.ex.x = mA + mB + m_rA.y * m_rA.y * iA + m_rB.y * m_rB.y * iB;
K.ey.x = -m_rA.y * m_rA.x * iA - m_rB.y * m_rB.x * iB;
K.ez.x = -m_rA.y * iA - m_rB.y * iB;
K.ex.y = K.ey.x;
K.ey.y = mA + mB + m_rA.x * m_rA.x * iA + m_rB.x * m_rB.x * iB;
K.ez.y = m_rA.x * iA + m_rB.x * iB;
K.ex.z = K.ez.x;
K.ey.z = K.ez.y;
K.ez.z = iA + iB;
if (m_frequencyHz > 0.0d)
{
K.getInverse22(m_mass);
double invM = iA + iB;
double m = invM > 0.0d ? 1.0d / invM : 0.0d;
double C = aB - aA - m_referenceAngle;
// Frequency
double omega = 2.0d * MathUtils.PI * m_frequencyHz;
// Damping coefficient
double d = 2.0d * m * m_dampingRatio * omega;
// Spring stiffness
double k = m * omega * omega;
// magic formulas
double h = data.step.dt;
m_gamma = h * (d + h * k);
m_gamma = m_gamma != 0.0d ? 1.0d / m_gamma : 0.0d;
m_bias = C * h * k * m_gamma;
invM += m_gamma;
m_mass.ez.z = invM != 0.0d ? 1.0d / invM : 0.0d;
}
else
{
K.getSymInverse33(m_mass);
m_gamma = 0.0d;
m_bias = 0.0d;
}
if (data.step.warmStarting)
{
Vec2 P = pool.popVec2();
// Scale impulses to support a variable time step.
m_impulse.mulLocal(data.step.dtRatio);
P.set(m_impulse.x, m_impulse.y);
vA.x -= mA * P.x;
vA.y -= mA * P.y;
wA -= iA * (Vec2.cross(m_rA, P) + m_impulse.z);
vB.x += mB * P.x;
vB.y += mB * P.y;
wB += iB * (Vec2.cross(m_rB, P) + m_impulse.z);
pool.pushVec2(1);
}
else
{
m_impulse.setZero();
}
// data.velocities[m_indexA].v.set(vA);
data.velocities[m_indexA].w = wA;
// data.velocities[m_indexB].v.set(vB);
data.velocities[m_indexB].w = wB;
pool.pushVec2(1);
pool.pushRot(2);
pool.pushMat33(1);
}
public override void initVelocityConstraints(SolverData data)
{
m_indexA = m_bodyA.m_islandIndex;
m_indexB = m_bodyB.m_islandIndex;
m_localCenterA.set(m_bodyA.m_sweep.localCenter);
m_localCenterB.set(m_bodyB.m_sweep.localCenter);
m_invMassA = m_bodyA.m_invMass;
m_invMassB = m_bodyB.m_invMass;
m_invIA = m_bodyA.m_invI;
m_invIB = m_bodyB.m_invI;
Vec2 cA = data.positions[m_indexA].c;
double aA = data.positions[m_indexA].a;
Vec2 vA = data.velocities[m_indexA].v;
double wA = data.velocities[m_indexA].w;
Vec2 cB = data.positions[m_indexB].c;
double aB = data.positions[m_indexB].a;
Vec2 vB = data.velocities[m_indexB].v;
double wB = data.velocities[m_indexB].w;
Rot qA = pool.popRot();
Rot qB = pool.popRot();
Vec2 d = pool.popVec2();
Vec2 temp = pool.popVec2();
Vec2 rA = pool.popVec2();
Vec2 rB = pool.popVec2();
qA.set(aA);
qB.set(aB);
// Compute the effective masses.
Rot.mulToOutUnsafe(qA, d.set(m_localAnchorA).subLocal(m_localCenterA), rA);
Rot.mulToOutUnsafe(qB, d.set(m_localAnchorB).subLocal(m_localCenterB), rB);
d.set(cB).subLocal(cA).addLocal(rB).subLocal(rA);
double mA = m_invMassA, mB = m_invMassB;
double iA = m_invIA, iB = m_invIB;
// Compute motor Jacobian and effective mass.
{
Rot.mulToOutUnsafe(qA, m_localXAxisA, m_axis);
temp.set(d).addLocal(rA);
m_a1 = Vec2.cross(temp, m_axis);
m_a2 = Vec2.cross(rB, m_axis);
m_motorMass = mA + mB + iA * m_a1 * m_a1 + iB * m_a2 * m_a2;
if (m_motorMass > 0.0d)
{
m_motorMass = 1.0d / m_motorMass;
}
}
// Prismatic constraint.
{
Rot.mulToOutUnsafe(qA, m_localYAxisA, m_perp);
temp.set(d).addLocal(rA);
m_s1 = Vec2.cross(temp, m_perp);
m_s2 = Vec2.cross(rB, m_perp);
double k11 = mA + mB + iA * m_s1 * m_s1 + iB * m_s2 * m_s2;
double k12 = iA * m_s1 + iB * m_s2;
double k13 = iA * m_s1 * m_a1 + iB * m_s2 * m_a2;
double k22 = iA + iB;
if (k22 == 0.0d)
{
// For bodies with fixed rotation.
k22 = 1.0d;
}
double k23 = iA * m_a1 + iB * m_a2;
double k33 = mA + mB + iA * m_a1 * m_a1 + iB * m_a2 * m_a2;
m_K.ex.set(k11, k12, k13);
m_K.ey.set(k12, k22, k23);
m_K.ez.set(k13, k23, k33);
}
// Compute motor and limit terms.
if (m_enableLimit)
{
double jointTranslation = Vec2.dot(m_axis, d);
if (MathUtils.abs(m_upperTranslation - m_lowerTranslation) < 2.0d * Settings.linearSlop)
{
m_limitState = LimitState.EQUAL;
}
else if (jointTranslation <= m_lowerTranslation)
{
if (m_limitState != LimitState.AT_LOWER)
{
m_limitState = LimitState.AT_LOWER;
m_impulse.z = 0.0d;
}
}
else if (jointTranslation >= m_upperTranslation)
{
if (m_limitState != LimitState.AT_UPPER)
{
m_limitState = LimitState.AT_UPPER;
m_impulse.z = 0.0d;
}
}
else
{
m_limitState = LimitState.INACTIVE;
m_impulse.z = 0.0d;
}
}
else
{
m_limitState = LimitState.INACTIVE;
m_impulse.z = 0.0d;
}
if (m_enableMotor == false)
{
m_motorImpulse = 0.0d;
}
if (data.step.warmStarting)
{
// Account for variable time step.
m_impulse.mulLocal(data.step.dtRatio);
m_motorImpulse *= data.step.dtRatio;
Vec2 P = pool.popVec2();
temp.set(m_axis).mulLocal(m_motorImpulse + m_impulse.z);
P.set(m_perp).mulLocal(m_impulse.x).addLocal(temp);
double LA = m_impulse.x * m_s1 + m_impulse.y + (m_motorImpulse + m_impulse.z) * m_a1;
double LB = m_impulse.x * m_s2 + m_impulse.y + (m_motorImpulse + m_impulse.z) * m_a2;
vA.x -= mA * P.x;
vA.y -= mA * P.y;
wA -= iA * LA;
vB.x += mB * P.x;
vB.y += mB * P.y;
wB += iB * LB;
pool.pushVec2(1);
}
else
{
m_impulse.setZero();
m_motorImpulse = 0.0d;
}
// data.velocities[m_indexA].v.set(vA);
data.velocities[m_indexA].w = wA;
// data.velocities[m_indexB].v.set(vB);
data.velocities[m_indexB].w = wB;
pool.pushRot(2);
pool.pushVec2(4);
}
public override void initVelocityConstraints(SolverData data)
{
m_indexA = m_bodyA.m_islandIndex;
m_indexB = m_bodyB.m_islandIndex;
m_localCenterA.set(m_bodyA.m_sweep.localCenter);
m_localCenterB.set(m_bodyB.m_sweep.localCenter);
m_invMassA = m_bodyA.m_invMass;
m_invMassB = m_bodyB.m_invMass;
m_invIA = m_bodyA.m_invI;
m_invIB = m_bodyB.m_invI;
Vec2 cA = data.positions[m_indexA].c;
double aA = data.positions[m_indexA].a;
Vec2 vA = data.velocities[m_indexA].v;
double wA = data.velocities[m_indexA].w;
Vec2 cB = data.positions[m_indexB].c;
double aB = data.positions[m_indexB].a;
Vec2 vB = data.velocities[m_indexB].v;
double wB = data.velocities[m_indexB].w;
Rot qA = pool.popRot();
Rot qB = pool.popRot();
Vec2 temp = pool.popVec2();
qA.set(aA);
qB.set(aB);
// Compute the effective masses.
Rot.mulToOutUnsafe(qA, temp.set(m_localAnchorA).subLocal(m_localCenterA), m_rA);
Rot.mulToOutUnsafe(qB, temp.set(m_localAnchorB).subLocal(m_localCenterB), m_rB);
m_u.set(cB).addLocal(m_rB).subLocal(cA).subLocal(m_rA);
m_length = m_u.length();
double C = m_length - m_maxLength;
if (C > 0.0d)
{
m_state = LimitState.AT_UPPER;
}
else
{
m_state = LimitState.INACTIVE;
}
if (m_length > Settings.linearSlop)
{
m_u.mulLocal(1.0d / m_length);
}
else
{
m_u.setZero();
m_mass = 0.0d;
m_impulse = 0.0d;
return;
}
// Compute effective mass.
double crA = Vec2.cross(m_rA, m_u);
double crB = Vec2.cross(m_rB, m_u);
double invMass = m_invMassA + m_invIA * crA * crA + m_invMassB + m_invIB * crB * crB;
m_mass = invMass != 0.0d ? 1.0d / invMass : 0.0d;
if (data.step.warmStarting)
{
// Scale the impulse to support a variable time step.
m_impulse *= data.step.dtRatio;
double Px = m_impulse * m_u.x;
double Py = m_impulse * m_u.y;
vA.x -= m_invMassA * Px;
vA.y -= m_invMassA * Py;
wA -= m_invIA * (m_rA.x * Py - m_rA.y * Px);
vB.x += m_invMassB * Px;
vB.y += m_invMassB * Py;
wB += m_invIB * (m_rB.x * Py - m_rB.y * Px);
}
else
{
m_impulse = 0.0d;
}
pool.pushRot(2);
pool.pushVec2(1);
// data.velocities[m_indexA].v = vA;
data.velocities[m_indexA].w = wA;
// data.velocities[m_indexB].v = vB;
data.velocities[m_indexB].w = wB;
}
public override bool solvePositionConstraints(SolverData data)
{
Rot qA = pool.popRot();
Rot qB = pool.popRot();
Vec2 rA = pool.popVec2();
Vec2 rB = pool.popVec2();
Vec2 d = pool.popVec2();
Vec2 axis = pool.popVec2();
Vec2 perp = pool.popVec2();
Vec2 temp = pool.popVec2();
Vec2 C1 = pool.popVec2();
Vec3 impulse = pool.popVec3();
Vec2 cA = data.positions[m_indexA].c;
double aA = data.positions[m_indexA].a;
Vec2 cB = data.positions[m_indexB].c;
double aB = data.positions[m_indexB].a;
qA.set(aA);
qB.set(aB);
double mA = m_invMassA, mB = m_invMassB;
double iA = m_invIA, iB = m_invIB;
// Compute fresh Jacobians
Rot.mulToOutUnsafe(qA, temp.set(m_localAnchorA).subLocal(m_localCenterA), rA);
Rot.mulToOutUnsafe(qB, temp.set(m_localAnchorB).subLocal(m_localCenterB), rB);
d.set(cB).addLocal(rB).subLocal(cA).subLocal(rA);
Rot.mulToOutUnsafe(qA, m_localXAxisA, axis);
double a1 = Vec2.cross(temp.set(d).addLocal(rA), axis);
double a2 = Vec2.cross(rB, axis);
Rot.mulToOutUnsafe(qA, m_localYAxisA, perp);
double s1 = Vec2.cross(temp.set(d).addLocal(rA), perp);
double s2 = Vec2.cross(rB, perp);
C1.x = Vec2.dot(perp, d);
C1.y = aB - aA - m_referenceAngle;
double linearError = MathUtils.abs(C1.x);
double angularError = MathUtils.abs(C1.y);
bool active = false;
double C2 = 0.0d;
if (m_enableLimit)
{
double translation = Vec2.dot(axis, d);
if (MathUtils.abs(m_upperTranslation - m_lowerTranslation) < 2.0d * Settings.linearSlop)
{
// Prevent large angular corrections
C2 =
MathUtils.clamp(translation, -Settings.maxLinearCorrection,
Settings.maxLinearCorrection);
linearError = MathUtils.max(linearError, MathUtils.abs(translation));
active = true;
}
else if (translation <= m_lowerTranslation)
{
// Prevent large linear corrections and allow some slop.
C2 =
MathUtils.clamp(translation - m_lowerTranslation + Settings.linearSlop,
-Settings.maxLinearCorrection, 0.0d);
linearError = MathUtils.max(linearError, m_lowerTranslation - translation);
active = true;
}
else if (translation >= m_upperTranslation)
{
// Prevent large linear corrections and allow some slop.
C2 =
MathUtils.clamp(translation - m_upperTranslation - Settings.linearSlop, 0.0d,
Settings.maxLinearCorrection);
linearError = MathUtils.max(linearError, translation - m_upperTranslation);
active = true;
}
}
if (active)
{
double k11 = mA + mB + iA * s1 * s1 + iB * s2 * s2;
double k12 = iA * s1 + iB * s2;
double k13 = iA * s1 * a1 + iB * s2 * a2;
double k22 = iA + iB;
if (k22 == 0.0d)
{
// For fixed rotation
k22 = 1.0d;
}
double k23 = iA * a1 + iB * a2;
double k33 = mA + mB + iA * a1 * a1 + iB * a2 * a2;
Mat33 K = pool.popMat33();
K.ex.set(k11, k12, k13);
K.ey.set(k12, k22, k23);
K.ez.set(k13, k23, k33);
Vec3 C = pool.popVec3();
C.x = C1.x;
C.y = C1.y;
C.z = C2;
K.solve33ToOut(C.negateLocal(), impulse);
pool.pushVec3(1);
pool.pushMat33(1);
}
else
{
double k11 = mA + mB + iA * s1 * s1 + iB * s2 * s2;
double k12 = iA * s1 + iB * s2;
double k22 = iA + iB;
if (k22 == 0.0d)
{
k22 = 1.0d;
}
Mat22 K = pool.popMat22();
K.ex.set(k11, k12);
K.ey.set(k12, k22);
// temp is impulse1
K.solveToOut(C1.negateLocal(), temp);
C1.negateLocal();
impulse.x = temp.x;
impulse.y = temp.y;
impulse.z = 0.0d;
pool.pushMat22(1);
}
double Px = impulse.x * perp.x + impulse.z * axis.x;
double Py = impulse.x * perp.y + impulse.z * axis.y;
double LA = impulse.x * s1 + impulse.y + impulse.z * a1;
double LB = impulse.x * s2 + impulse.y + impulse.z * a2;
cA.x -= mA * Px;
cA.y -= mA * Py;
aA -= iA * LA;
cB.x += mB * Px;
cB.y += mB * Py;
aB += iB * LB;
// data.positions[m_indexA].c.set(cA);
data.positions[m_indexA].a = aA;
// data.positions[m_indexB].c.set(cB);
data.positions[m_indexB].a = aB;
pool.pushVec2(7);
pool.pushVec3(1);
pool.pushRot(2);
return(linearError <= Settings.linearSlop && angularError <= Settings.angularSlop);
}
public override void initVelocityConstraints(SolverData data)
{
m_indexA = m_bodyA.m_islandIndex;
m_indexB = m_bodyB.m_islandIndex;
m_localCenterA.set(m_bodyA.m_sweep.localCenter);
m_localCenterB.set(m_bodyB.m_sweep.localCenter);
m_invMassA = m_bodyA.m_invMass;
m_invMassB = m_bodyB.m_invMass;
m_invIA = m_bodyA.m_invI;
m_invIB = m_bodyB.m_invI;
Vec2 cA = data.positions[m_indexA].c;
double aA = data.positions[m_indexA].a;
Vec2 vA = data.velocities[m_indexA].v;
double wA = data.velocities[m_indexA].w;
Vec2 cB = data.positions[m_indexB].c;
double aB = data.positions[m_indexB].a;
Vec2 vB = data.velocities[m_indexB].v;
double wB = data.velocities[m_indexB].w;
Rot qA = pool.popRot();
Rot qB = pool.popRot();
qA.set(aA);
qB.set(aB);
// use m_u as temporary variable
Rot.mulToOutUnsafe(qA, m_u.set(m_localAnchorA).subLocal(m_localCenterA), m_rA);
Rot.mulToOutUnsafe(qB, m_u.set(m_localAnchorB).subLocal(m_localCenterB), m_rB);
m_u.set(cB).addLocal(m_rB).subLocal(cA).subLocal(m_rA);
pool.pushRot(2);
// Handle singularity.
double length = m_u.length();
if (length > Settings.linearSlop)
{
m_u.x *= 1.0d / length;
m_u.y *= 1.0d / length;
}
else
{
m_u.set(0.0d, 0.0d);
}
double crAu = Vec2.cross(m_rA, m_u);
double crBu = Vec2.cross(m_rB, m_u);
double invMass = m_invMassA + m_invIA * crAu * crAu + m_invMassB + m_invIB * crBu * crBu;
// Compute the effective mass matrix.
m_mass = invMass != 0.0d ? 1.0d / invMass : 0.0d;
if (m_frequencyHz > 0.0d)
{
double C = length - m_length;
// Frequency
double omega = 2.0d * MathUtils.PI * m_frequencyHz;
// Damping coefficient
double d = 2.0d * m_mass * m_dampingRatio * omega;
// Spring stiffness
double k = m_mass * omega * omega;
// magic formulas
double h = data.step.dt;
m_gamma = h * (d + h * k);
m_gamma = m_gamma != 0.0d ? 1.0d / m_gamma : 0.0d;
m_bias = C * h * k * m_gamma;
invMass += m_gamma;
m_mass = invMass != 0.0d ? 1.0d / invMass : 0.0d;
}
else
{
m_gamma = 0.0d;
m_bias = 0.0d;
}
if (data.step.warmStarting)
{
// Scale the impulse to support a variable time step.
m_impulse *= data.step.dtRatio;
Vec2 P = pool.popVec2();
P.set(m_u).mulLocal(m_impulse);
vA.x -= m_invMassA * P.x;
vA.y -= m_invMassA * P.y;
wA -= m_invIA * Vec2.cross(m_rA, P);
vB.x += m_invMassB * P.x;
vB.y += m_invMassB * P.y;
wB += m_invIB * Vec2.cross(m_rB, P);
pool.pushVec2(1);
}
else
{
m_impulse = 0.0d;
}
// data.velocities[m_indexA].v.set(vA);
data.velocities[m_indexA].w = wA;
// data.velocities[m_indexB].v.set(vB);
data.velocities[m_indexB].w = wB;
}
public override bool solvePositionConstraints(SolverData data)
{
Rot qA = pool.popRot();
Rot qB = pool.popRot();
Vec2 rA = pool.popVec2();
Vec2 rB = pool.popVec2();
Vec2 uA = pool.popVec2();
Vec2 uB = pool.popVec2();
Vec2 temp = pool.popVec2();
Vec2 PA = pool.popVec2();
Vec2 PB = pool.popVec2();
Vec2 cA = data.positions[m_indexA].c;
double aA = data.positions[m_indexA].a;
Vec2 cB = data.positions[m_indexB].c;
double aB = data.positions[m_indexB].a;
qA.set(aA);
qB.set(aB);
Rot.mulToOutUnsafe(qA, temp.set(m_localAnchorA).subLocal(m_localCenterA), rA);
Rot.mulToOutUnsafe(qB, temp.set(m_localAnchorB).subLocal(m_localCenterB), rB);
uA.set(cA).addLocal(rA).subLocal(m_groundAnchorA);
uB.set(cB).addLocal(rB).subLocal(m_groundAnchorB);
double lengthA = uA.length();
double lengthB = uB.length();
if (lengthA > 10.0d * Settings.linearSlop)
{
uA.mulLocal(1.0d / lengthA);
}
else
{
uA.setZero();
}
if (lengthB > 10.0d * Settings.linearSlop)
{
uB.mulLocal(1.0d / lengthB);
}
else
{
uB.setZero();
}
// Compute effective mass.
double ruA = Vec2.cross(rA, uA);
double ruB = Vec2.cross(rB, uB);
double mA = m_invMassA + m_invIA * ruA * ruA;
double mB = m_invMassB + m_invIB * ruB * ruB;
double mass = mA + m_ratio * m_ratio * mB;
if (mass > 0.0d)
{
mass = 1.0d / mass;
}
double C = m_constant - lengthA - m_ratio * lengthB;
double linearError = MathUtils.abs(C);
double impulse = -mass * C;
PA.set(uA).mulLocal(-impulse);
PB.set(uB).mulLocal(-m_ratio * impulse);
cA.x += m_invMassA * PA.x;
cA.y += m_invMassA * PA.y;
aA += m_invIA * Vec2.cross(rA, PA);
cB.x += m_invMassB * PB.x;
cB.y += m_invMassB * PB.y;
aB += m_invIB * Vec2.cross(rB, PB);
// data.positions[m_indexA].c.set(cA);
data.positions[m_indexA].a = aA;
// data.positions[m_indexB].c.set(cB);
data.positions[m_indexB].a = aB;
pool.pushRot(2);
pool.pushVec2(7);
return(linearError < Settings.linearSlop);
}
public override void initVelocityConstraints(SolverData data)
{
m_indexA = m_bodyA.m_islandIndex;
m_indexB = m_bodyB.m_islandIndex;
m_indexC = m_bodyC.m_islandIndex;
m_indexD = m_bodyD.m_islandIndex;
m_lcA.set(m_bodyA.m_sweep.localCenter);
m_lcB.set(m_bodyB.m_sweep.localCenter);
m_lcC.set(m_bodyC.m_sweep.localCenter);
m_lcD.set(m_bodyD.m_sweep.localCenter);
m_mA = m_bodyA.m_invMass;
m_mB = m_bodyB.m_invMass;
m_mC = m_bodyC.m_invMass;
m_mD = m_bodyD.m_invMass;
m_iA = m_bodyA.m_invI;
m_iB = m_bodyB.m_invI;
m_iC = m_bodyC.m_invI;
m_iD = m_bodyD.m_invI;
// Vec2 cA = data.positions[m_indexA].c;
double aA = data.positions[m_indexA].a;
Vec2 vA = data.velocities[m_indexA].v;
double wA = data.velocities[m_indexA].w;
// Vec2 cB = data.positions[m_indexB].c;
double aB = data.positions[m_indexB].a;
Vec2 vB = data.velocities[m_indexB].v;
double wB = data.velocities[m_indexB].w;
// Vec2 cC = data.positions[m_indexC].c;
double aC = data.positions[m_indexC].a;
Vec2 vC = data.velocities[m_indexC].v;
double wC = data.velocities[m_indexC].w;
// Vec2 cD = data.positions[m_indexD].c;
double aD = data.positions[m_indexD].a;
Vec2 vD = data.velocities[m_indexD].v;
double wD = data.velocities[m_indexD].w;
Rot qA = pool.popRot(), qB = pool.popRot(), qC = pool.popRot(), qD = pool.popRot();
qA.set(aA);
qB.set(aB);
qC.set(aC);
qD.set(aD);
m_mass = 0.0d;
Vec2 temp = pool.popVec2();
if (m_typeA == JointType.REVOLUTE)
{
m_JvAC.setZero();
m_JwA = 1.0d;
m_JwC = 1.0d;
m_mass += m_iA + m_iC;
}
else
{
Vec2 rC = pool.popVec2();
Vec2 rA = pool.popVec2();
Rot.mulToOutUnsafe(qC, m_localAxisC, m_JvAC);
Rot.mulToOutUnsafe(qC, temp.set(m_localAnchorC).subLocal(m_lcC), rC);
Rot.mulToOutUnsafe(qA, temp.set(m_localAnchorA).subLocal(m_lcA), rA);
m_JwC = Vec2.cross(rC, m_JvAC);
m_JwA = Vec2.cross(rA, m_JvAC);
m_mass += m_mC + m_mA + m_iC * m_JwC * m_JwC + m_iA * m_JwA * m_JwA;
pool.pushVec2(2);
}
if (m_typeB == JointType.REVOLUTE)
{
m_JvBD.setZero();
m_JwB = m_ratio;
m_JwD = m_ratio;
m_mass += m_ratio * m_ratio * (m_iB + m_iD);
}
else
{
Vec2 u = pool.popVec2();
Vec2 rD = pool.popVec2();
Vec2 rB = pool.popVec2();
Rot.mulToOutUnsafe(qD, m_localAxisD, u);
Rot.mulToOutUnsafe(qD, temp.set(m_localAnchorD).subLocal(m_lcD), rD);
Rot.mulToOutUnsafe(qB, temp.set(m_localAnchorB).subLocal(m_lcB), rB);
m_JvBD.set(u).mulLocal(m_ratio);
m_JwD = m_ratio * Vec2.cross(rD, u);
m_JwB = m_ratio * Vec2.cross(rB, u);
m_mass += m_ratio * m_ratio * (m_mD + m_mB) + m_iD * m_JwD * m_JwD + m_iB * m_JwB * m_JwB;
pool.pushVec2(3);
}
// Compute effective mass.
m_mass = m_mass > 0.0d ? 1.0d / m_mass : 0.0d;
if (data.step.warmStarting)
{
vA.x += (m_mA * m_impulse) * m_JvAC.x;
vA.y += (m_mA * m_impulse) * m_JvAC.y;
wA += m_iA * m_impulse * m_JwA;
vB.x += (m_mB * m_impulse) * m_JvBD.x;
vB.y += (m_mB * m_impulse) * m_JvBD.y;
wB += m_iB * m_impulse * m_JwB;
vC.x -= (m_mC * m_impulse) * m_JvAC.x;
vC.y -= (m_mC * m_impulse) * m_JvAC.y;
wC -= m_iC * m_impulse * m_JwC;
vD.x -= (m_mD * m_impulse) * m_JvBD.x;
vD.y -= (m_mD * m_impulse) * m_JvBD.y;
wD -= m_iD * m_impulse * m_JwD;
}
else
{
m_impulse = 0.0d;
}
pool.pushVec2(1);
pool.pushRot(4);
// data.velocities[m_indexA].v = vA;
data.velocities[m_indexA].w = wA;
// data.velocities[m_indexB].v = vB;
data.velocities[m_indexB].w = wB;
// data.velocities[m_indexC].v = vC;
data.velocities[m_indexC].w = wC;
// data.velocities[m_indexD].v = vD;
data.velocities[m_indexD].w = wD;
}