public override void SynchronizeMotionStates()
{
///@todo: iterate over awake simulation islands!
foreach (CollisionObject colObj in m_collisionObjects)
{
RigidBody body = RigidBody.Upcast(colObj);
if (body != null && body.GetMotionState() != null)
{
if (body.GetActivationState() != ActivationState.ISLAND_SLEEPING)
{
body.GetMotionState().SetWorldTransform(body.GetWorldTransform());
}
}
}
}
//response between two dynamic objects without friction, assuming 0 penetration depth
public static float ResolveSingleCollision(
RigidBody body1,
CollisionObject colObj2,
ref IndexedVector3 contactPositionWorld,
ref IndexedVector3 contactNormalOnB,
ContactSolverInfo solverInfo,
float distance)
{
RigidBody body2 = RigidBody.Upcast(colObj2);
IndexedVector3 normal = contactNormalOnB;
IndexedVector3 rel_pos1 = contactPositionWorld - body1.GetWorldTransform()._origin;
IndexedVector3 rel_pos2 = contactPositionWorld - colObj2.GetWorldTransform()._origin;
IndexedVector3 vel1 = body1.GetVelocityInLocalPoint(ref rel_pos1);
IndexedVector3 vel2 = body2 != null?body2.GetVelocityInLocalPoint(ref rel_pos2) : IndexedVector3.Zero;
IndexedVector3 vel = vel1 - vel2;
float rel_vel = normal.Dot(ref vel);
float combinedRestitution = body1.GetRestitution() * colObj2.GetRestitution();
float restitution = combinedRestitution * -rel_vel;
float positionalError = solverInfo.m_erp * -distance / solverInfo.m_timeStep;
float velocityError = -(1.0f + restitution) * rel_vel; // * damping;
float denom0 = body1.ComputeImpulseDenominator(ref contactPositionWorld, ref normal);
float denom1 = body2 != null?body2.ComputeImpulseDenominator(ref contactPositionWorld, ref normal) : 0.0f;
float relaxation = 1.0f;
float jacDiagABInv = relaxation / (denom0 + denom1);
float penetrationImpulse = positionalError * jacDiagABInv;
float velocityImpulse = velocityError * jacDiagABInv;
float normalImpulse = penetrationImpulse + velocityImpulse;
normalImpulse = 0.0f > normalImpulse ? 0.0f : normalImpulse;
body1.ApplyImpulse(normal * (normalImpulse), rel_pos1);
if (body2 != null)
{
body2.ApplyImpulse(-normal * (normalImpulse), rel_pos2);
}
return(normalImpulse);
}
public virtual void IntegrateTransforms(float timeStep)
{
BulletGlobals.StartProfile("integrateTransforms");
IndexedMatrix predictedTrans;
int length = m_nonStaticRigidBodies.Count;
#if DEBUG
if (BulletGlobals.g_streamWriter != null && BulletGlobals.debugDiscreteDynamicsWorld)
{
BulletGlobals.g_streamWriter.WriteLine("IntegrateTransforms [{0}]", length);
}
#endif
for (int i = 0; i < length; ++i)
{
RigidBody body = m_nonStaticRigidBodies[i];
if (body != null)
{
body.SetHitFraction(1f);
if (body.IsActive() && (!body.IsStaticOrKinematicObject()))
{
body.PredictIntegratedTransform(timeStep, out predictedTrans);
float squareMotion = (predictedTrans._origin - body.GetWorldTransform()._origin).LengthSquared();
//if (body.GetCcdSquareMotionThreshold() != 0 && body.GetCcdSquareMotionThreshold() < squareMotion)
if (GetDispatchInfo().m_useContinuous&& body.GetCcdSquareMotionThreshold() != 0.0f && body.GetCcdSquareMotionThreshold() < squareMotion)
{
BulletGlobals.StartProfile("CCD motion clamping");
if (body.GetCollisionShape().IsConvex())
{
gNumClampedCcdMotions++;
using (ClosestNotMeConvexResultCallback sweepResults = BulletGlobals.ClosestNotMeConvexResultCallbackPool.Get())
{
sweepResults.Initialize(body, body.GetWorldTransform()._origin, predictedTrans._origin, GetBroadphase().GetOverlappingPairCache(), GetDispatcher());
//btConvexShape* convexShape = static_cast<btConvexShape*>(body.GetCollisionShape());
SphereShape tmpSphere = BulletGlobals.SphereShapePool.Get();
tmpSphere.Initialize(body.GetCcdSweptSphereRadius());//btConvexShape* convexShape = static_cast<btConvexShape*>(body.GetCollisionShape());
sweepResults.m_allowedPenetration = GetDispatchInfo().GetAllowedCcdPenetration();
sweepResults.m_collisionFilterGroup = body.GetBroadphaseProxy().m_collisionFilterGroup;
sweepResults.m_collisionFilterMask = body.GetBroadphaseProxy().m_collisionFilterMask;
IndexedMatrix modifiedPredictedTrans = predictedTrans;
modifiedPredictedTrans._basis = body.GetWorldTransform()._basis;
modifiedPredictedTrans._origin = predictedTrans._origin;
ConvexSweepTest(tmpSphere, body.GetWorldTransform(), modifiedPredictedTrans, sweepResults, 0f);
if (sweepResults.HasHit() && (sweepResults.m_closestHitFraction < 1.0f))
{
//printf("clamped integration to hit fraction = %f\n",fraction);
body.SetHitFraction(sweepResults.m_closestHitFraction);
body.PredictIntegratedTransform(timeStep * body.GetHitFraction(), out predictedTrans);
body.SetHitFraction(0.0f);
body.ProceedToTransform(ref predictedTrans);
#if false
btVector3 linVel = body.getLinearVelocity();
float maxSpeed = body.getCcdMotionThreshold() / getSolverInfo().m_timeStep;
float maxSpeedSqr = maxSpeed * maxSpeed;
if (linVel.LengthSquared() > maxSpeedSqr)
{
linVel.normalize();
linVel *= maxSpeed;
body.setLinearVelocity(linVel);
float ms2 = body.getLinearVelocity().LengthSquared();
body.predictIntegratedTransform(timeStep, predictedTrans);
float sm2 = (predictedTrans._origin - body.GetWorldTransform()._origin).LengthSquared();
float smt = body.getCcdSquareMotionThreshold();
printf("sm2=%f\n", sm2);
}
#else
//response between two dynamic objects without friction, assuming 0 penetration depth
float appliedImpulse = 0.0f;
float depth = 0.0f;
appliedImpulse = ContactConstraint.ResolveSingleCollision(body, sweepResults.m_hitCollisionObject, ref sweepResults.m_hitPointWorld, ref sweepResults.m_hitNormalWorld, GetSolverInfo(), depth);
#endif
continue;
}
BulletGlobals.SphereShapePool.Free(tmpSphere);
}
}
BulletGlobals.StopProfile();
}
body.ProceedToTransform(ref predictedTrans);
}
}
}
}