///bilateral constraint between two dynamic objects
///positive distance = separation, negative distance = penetration
public static void ResolveSingleBilateral(RigidBody body1, ref IndexedVector3 pos1,
RigidBody body2, ref IndexedVector3 pos2,
float distance, ref IndexedVector3 normal, ref float impulse, float timeStep)
{
float normalLenSqr = normal.LengthSquared();
Debug.Assert(Math.Abs(normalLenSqr) < 1.1f);
if (normalLenSqr > 1.1f)
{
impulse = 0f;
return;
}
IndexedVector3 rel_pos1 = pos1 - body1.GetCenterOfMassPosition();
IndexedVector3 rel_pos2 = pos2 - body2.GetCenterOfMassPosition();
//this jacobian entry could be re-used for all iterations
IndexedVector3 vel1 = body1.GetVelocityInLocalPoint(ref rel_pos1);
IndexedVector3 vel2 = body2.GetVelocityInLocalPoint(ref rel_pos2);
IndexedVector3 vel = vel1 - vel2;
IndexedBasisMatrix m1 = body1.GetCenterOfMassTransform()._basis.Transpose();
IndexedBasisMatrix m2 = body2.GetCenterOfMassTransform()._basis.Transpose();
JacobianEntry jac = new JacobianEntry(m1, m2, rel_pos1, rel_pos2, normal,
body1.GetInvInertiaDiagLocal(), body1.GetInvMass(),
body2.GetInvInertiaDiagLocal(), body2.GetInvMass());
float jacDiagAB = jac.GetDiagonal();
float jacDiagABInv = 1f / jacDiagAB;
float rel_vel = jac.GetRelativeVelocity(
body1.GetLinearVelocity(),
body1.GetCenterOfMassTransform()._basis.Transpose() * body1.GetAngularVelocity(),
body2.GetLinearVelocity(),
body2.GetCenterOfMassTransform()._basis.Transpose() * body2.GetAngularVelocity());
float a = jacDiagABInv;
rel_vel = normal.Dot(ref vel);
//todo: move this into proper structure
float contactDamping = 0.2f;
if (ONLY_USE_LINEAR_MASS)
{
float massTerm = 1f / (body1.GetInvMass() + body2.GetInvMass());
impulse = -contactDamping * rel_vel * massTerm;
}
else
{
float velocityImpulse = -contactDamping * rel_vel * jacDiagABInv;
impulse = velocityImpulse;
}
}
protected void SetFrictionConstraintImpulse(ref SolverConstraint solverConstraint, RigidBody rb0, RigidBody rb1,
ManifoldPoint cp, ContactSolverInfo infoGlobal)
{
if (TestSolverMode(infoGlobal.m_solverMode, SolverMode.SOLVER_USE_FRICTION_WARMSTARTING))
{
{
SolverConstraint frictionConstraint1 = m_tmpSolverContactFrictionConstraintPool[solverConstraint.m_frictionIndex];
if (TestSolverMode(infoGlobal.m_solverMode, SolverMode.SOLVER_USE_WARMSTARTING))
{
frictionConstraint1.m_appliedImpulse = cp.m_appliedImpulseLateral1 * infoGlobal.m_warmstartingFactor;
if (rb0 != null)
{
rb0.InternalApplyImpulse(frictionConstraint1.m_contactNormal * rb0.GetInvMass(), frictionConstraint1.m_angularComponentA, frictionConstraint1.m_appliedImpulse,"SetupFriction-rb0");
}
if (rb1 != null)
{
rb1.InternalApplyImpulse(frictionConstraint1.m_contactNormal * rb1.GetInvMass(), -frictionConstraint1.m_angularComponentB, -frictionConstraint1.m_appliedImpulse, "SetupFriction-rb1");
}
}
else
{
frictionConstraint1.m_appliedImpulse = 0f;
}
m_tmpSolverContactFrictionConstraintPool[solverConstraint.m_frictionIndex] = frictionConstraint1;
}
if (TestSolverMode(infoGlobal.m_solverMode, SolverMode.SOLVER_USE_2_FRICTION_DIRECTIONS))
{
SolverConstraint frictionConstraint2 = m_tmpSolverContactFrictionConstraintPool[solverConstraint.m_frictionIndex + 1];
if (TestSolverMode(infoGlobal.m_solverMode, SolverMode.SOLVER_USE_WARMSTARTING))
{
frictionConstraint2.m_appliedImpulse = cp.m_appliedImpulseLateral2 * infoGlobal.m_warmstartingFactor;
if (rb0 != null)
{
rb0.InternalApplyImpulse(frictionConstraint2.m_contactNormal * rb0.GetInvMass(), frictionConstraint2.m_angularComponentA, frictionConstraint2.m_appliedImpulse,"SetFriction-rb0");
}
if (rb1 != null)
{
rb1.InternalApplyImpulse(frictionConstraint2.m_contactNormal * rb1.GetInvMass(), -frictionConstraint2.m_angularComponentB, -frictionConstraint2.m_appliedImpulse,"SetFriction-rb1");
}
}
else
{
frictionConstraint2.m_appliedImpulse = 0f;
}
m_tmpSolverContactFrictionConstraintPool[solverConstraint.m_frictionIndex + 1] = frictionConstraint2;
}
}
else
{
SolverConstraint frictionConstraint1 = m_tmpSolverContactFrictionConstraintPool[solverConstraint.m_frictionIndex];
frictionConstraint1.m_appliedImpulse = 0f;
if (TestSolverMode(infoGlobal.m_solverMode, SolverMode.SOLVER_USE_2_FRICTION_DIRECTIONS))
{
SolverConstraint frictionConstraint2 = m_tmpSolverContactFrictionConstraintPool[solverConstraint.m_frictionIndex + 1];
frictionConstraint2.m_appliedImpulse = 0f;
m_tmpSolverContactFrictionConstraintPool[solverConstraint.m_frictionIndex + 1] = frictionConstraint2;
}
m_tmpSolverContactFrictionConstraintPool[solverConstraint.m_frictionIndex] = frictionConstraint1;
}
}
public float SolveLinearAxis(
float timeStep,
float jacDiagABInv,
RigidBody body1, ref IndexedVector3 pointInA,
RigidBody body2, ref IndexedVector3 pointInB,
int limit_index,
ref IndexedVector3 axis_normal_on_a,
ref IndexedVector3 anchorPos)
{
///find relative velocity
// IndexedVector3 rel_pos1 = pointInA - body1.getCenterOfMassPosition();
// IndexedVector3 rel_pos2 = pointInB - body2.getCenterOfMassPosition();
IndexedVector3 rel_pos1 = anchorPos - body1.GetCenterOfMassPosition();
IndexedVector3 rel_pos2 = anchorPos - body2.GetCenterOfMassPosition();
IndexedVector3 vel1 = IndexedVector3.Zero;
body1.InternalGetVelocityInLocalPointObsolete(ref rel_pos1, ref vel1);
IndexedVector3 vel2 = IndexedVector3.Zero; ;
body2.InternalGetVelocityInLocalPointObsolete(ref rel_pos2, ref vel2);
IndexedVector3 vel = vel1 - vel2;
float rel_vel = IndexedVector3.Dot(axis_normal_on_a, vel);
/// apply displacement correction
//positional error (zeroth order error)
float depth = -IndexedVector3.Dot((pointInA - pointInB), axis_normal_on_a);
float lo = float.MinValue;
float hi = float.MaxValue;
float minLimit = m_lowerLimit[limit_index];
float maxLimit = m_upperLimit[limit_index];
//handle the limits
if (minLimit < maxLimit)
{
{
if (depth > maxLimit)
{
depth -= maxLimit;
lo = 0f;
}
else
{
if (depth < minLimit)
{
depth -= minLimit;
hi = 0f;
}
else
{
return 0.0f;
}
}
}
}
float normalImpulse = m_limitSoftness * (m_restitution * depth / timeStep - m_damping * rel_vel) * jacDiagABInv;
float oldNormalImpulse = m_accumulatedImpulse[limit_index];
float sum = oldNormalImpulse + normalImpulse;
m_accumulatedImpulse[limit_index] = (sum > hi ? 0f : sum < lo ? 0f : sum);
normalImpulse = m_accumulatedImpulse[limit_index] - oldNormalImpulse;
IndexedVector3 impulse_vector = axis_normal_on_a * normalImpulse;
//body1.applyImpulse( impulse_vector, rel_pos1);
//body2.applyImpulse(-impulse_vector, rel_pos2);
IndexedVector3 ftorqueAxis1 = IndexedVector3.Cross(rel_pos1, axis_normal_on_a);
IndexedVector3 ftorqueAxis2 = IndexedVector3.Cross(rel_pos2, axis_normal_on_a);
body1.InternalApplyImpulse(axis_normal_on_a * body1.GetInvMass(), body1.GetInvInertiaTensorWorld() * ftorqueAxis1, normalImpulse, "Generic6DoF body1");
body2.InternalApplyImpulse(axis_normal_on_a * body2.GetInvMass(), body2.GetInvInertiaTensorWorld() * ftorqueAxis2, -normalImpulse, "Generic6DoF body2");
return normalImpulse;
}
///bilateral constraint between two dynamic objects
///positive distance = separation, negative distance = penetration
public static void ResolveSingleBilateral(RigidBody body1, ref IndexedVector3 pos1,
RigidBody body2, ref IndexedVector3 pos2,
float distance, ref IndexedVector3 normal, ref float impulse, float timeStep)
{
float normalLenSqr = normal.LengthSquared();
Debug.Assert(Math.Abs(normalLenSqr) < 1.1f);
if (normalLenSqr > 1.1f)
{
impulse = 0f;
return;
}
IndexedVector3 rel_pos1 = pos1 - body1.GetCenterOfMassPosition();
IndexedVector3 rel_pos2 = pos2 - body2.GetCenterOfMassPosition();
//this jacobian entry could be re-used for all iterations
IndexedVector3 vel1 = body1.GetVelocityInLocalPoint(ref rel_pos1);
IndexedVector3 vel2 = body2.GetVelocityInLocalPoint(ref rel_pos2);
IndexedVector3 vel = vel1 - vel2;
IndexedBasisMatrix m1 = body1.GetCenterOfMassTransform()._basis.Transpose();
IndexedBasisMatrix m2 = body2.GetCenterOfMassTransform()._basis.Transpose();
JacobianEntry jac = new JacobianEntry(m1, m2, rel_pos1, rel_pos2, normal,
body1.GetInvInertiaDiagLocal(), body1.GetInvMass(),
body2.GetInvInertiaDiagLocal(), body2.GetInvMass());
float jacDiagAB = jac.GetDiagonal();
float jacDiagABInv = 1f / jacDiagAB;
float rel_vel = jac.GetRelativeVelocity(
body1.GetLinearVelocity(),
body1.GetCenterOfMassTransform()._basis.Transpose() * body1.GetAngularVelocity(),
body2.GetLinearVelocity(),
body2.GetCenterOfMassTransform()._basis.Transpose() * body2.GetAngularVelocity());
float a = jacDiagABInv;
rel_vel = normal.Dot(ref vel);
//todo: move this into proper structure
float contactDamping = 0.2f;
if (ONLY_USE_LINEAR_MASS)
{
float massTerm = 1f / (body1.GetInvMass() + body2.GetInvMass());
impulse = -contactDamping * rel_vel * massTerm;
}
else
{
float velocityImpulse = -contactDamping * rel_vel * jacDiagABInv;
impulse = velocityImpulse;
}
}
