public static void Multiply(ref btQuaternion q1, ref btQuaternion q2, out btQuaternion qout)
{
qout.X = q1.W * q2.X + q1.X * q2.W + q1.Y * q2.Z - q1.Z * q2.Y;
qout.Y = q1.W * q2.Y + q1.Y * q2.W + q1.Z * q2.X - q1.X * q2.Z;
qout.Z = q1.W * q2.Z + q1.Z * q2.W + q1.X * q2.Y - q1.Y * q2.X;
qout.W = q1.W * q2.W - q1.X * q2.X - q1.Y * q2.Y - q1.Z * q2.Z;
}
public btMatrix3x3(btQuaternion q)
{
float d = q.Length2;
Debug.Assert(d != 0.0f);
float s = 2.0f / d;
float xs = q.X * s, ys = q.Y * s, zs = q.Z * s;
float wx = q.W * xs, wy = q.W * ys, wz = q.W * zs;
float xx = q.X * xs, xy = q.X * ys, xz = q.X * zs;
float yy = q.Y * ys, yz = q.Y * zs, zz = q.Z * zs;
el0 = new btVector3(1.0f - (yy + zz), xy - wz, xz + wy);
el1 = new btVector3(xy + wz, 1.0f - (xx + zz), yz - wx);
el2 = new btVector3(xz - wy, yz + wx, 1.0f - (xx + yy));
}
public override void processCollision(CollisionObject body0, CollisionObject body1, DispatcherInfo dispatchInfo, ref ManifoldResult resultOut)
{
if (m_manifoldPtr == null)
return;
CollisionObject convexObj = m_isSwapped ? body1 : body0;
CollisionObject planeObj = m_isSwapped ? body0 : body1;
ConvexShape convexShape = (ConvexShape)convexObj.CollisionShape;
StaticPlaneShape planeShape = (StaticPlaneShape)planeObj.CollisionShape;
btVector3 planeNormal = planeShape.PlaneNormal;
//const btScalar& planeConstant = planeShape->getPlaneConstant();
//first perform a collision query with the non-perturbated collision objects
{
btQuaternion rotq = new btQuaternion(0, 0, 0, 1);
collideSingleContact(rotq, body0, body1, dispatchInfo, ref resultOut);
}
if (resultOut.PersistentManifold.NumContacts < m_minimumPointsPerturbationThreshold)
{
btVector3 v0, v1;
btVector3.PlaneSpace1(ref planeNormal, out v0, out v1);
//now perform 'm_numPerturbationIterations' collision queries with the perturbated collision objects
float angleLimit = 0.125f * BulletGlobal.SIMD_PI;
float perturbeAngle;
float radius = convexShape.getAngularMotionDisc();
perturbeAngle = PersistentManifold.gContactBreakingThreshold / radius;
if (perturbeAngle > angleLimit)
perturbeAngle = angleLimit;
btQuaternion perturbeRot = new btQuaternion(v0, perturbeAngle);
for (int i = 0; i < m_numPerturbationIterations; i++)
{
float iterationAngle = (float)i * (BulletGlobal.SIMD_2_PI / (float)m_numPerturbationIterations);
btQuaternion rotq = new btQuaternion(planeNormal, iterationAngle);
collideSingleContact(rotq.inverse() * perturbeRot * rotq, body0, body1, dispatchInfo, ref resultOut);
}
}
if (m_ownManifold)
{
if (m_manifoldPtr.NumContacts != 0)
{
resultOut.refreshContactPoints();
}
}
}
public static void integrateTransform(btTransform curTrans,btVector3 linvel, btVector3 angvel, float timeStep,out btTransform predictedTransform)
{
predictedTransform = btTransform.Identity;
#region predictedTransform.Origin=curTrans.Origin + linvel * timeStep;
{
btVector3 temp;
btVector3.Multiply(ref linvel, timeStep, out temp);
btVector3.Add(ref curTrans.Origin, ref temp, out predictedTransform.Origin);
}
#endregion
//Exponential map
//google for "Practical Parameterization of Rotations Using the Exponential Map", F. Sebastian Grassia
btVector3 axis;
float fAngle = angvel.Length;
//limit the angular motion
if (fAngle * timeStep > ANGULAR_MOTION_THRESHOLD)
{
fAngle = ANGULAR_MOTION_THRESHOLD / timeStep;
}
if (fAngle < 0.001f)
{
// use Taylor's expansions of sync function
#region axis = angvel * (0.5f * timeStep - (timeStep * timeStep * timeStep) * (0.020833333333f) * fAngle * fAngle);
{
btVector3.Multiply(ref angvel, (0.5f * timeStep - (timeStep * timeStep * timeStep) * (0.020833333333f) * fAngle * fAngle), out axis);
}
#endregion
}
else
{
// sync(fAngle) = sin(c*fAngle)/t
#region axis = angvel * ((float)Math.Sin(0.5f * fAngle * timeStep) / fAngle);
btVector3.Multiply(ref angvel, ((float)Math.Sin(0.5f * fAngle * timeStep) / fAngle), out axis);
#endregion
}
btQuaternion dorn = new btQuaternion(axis.X, axis.Y, axis.Z, (float)Math.Cos(fAngle * timeStep * 0.5f));
btQuaternion orn0 = curTrans.Rotation;
btQuaternion predictedOrn;
btQuaternion.Multiply(ref dorn, ref orn0, out predictedOrn);
predictedOrn.normalize();
predictedTransform.Rotation = predictedOrn;
}
public override void processCollision(CollisionObject body0, CollisionObject body1, DispatcherInfo dispatchInfo, ref ManifoldResult resultOut)
{
if (m_manifoldPtr == null)
{
//swapped?
m_manifoldPtr = m_dispatcher.getNewManifold(body0, body1);
m_ownManifold = true;
}
resultOut.PersistentManifold = m_manifoldPtr;
//comment-out next line to test multi-contact generation
//resultOut->getPersistentManifold()->clearManifold();
ConvexShape min0 = (ConvexShape)(body0.CollisionShape);
ConvexShape min1 = (ConvexShape)(body1.CollisionShape);
btVector3 normalOnB;
btVector3 pointOnBWorld;
if ((min0.ShapeType == BroadphaseNativeTypes.CAPSULE_SHAPE_PROXYTYPE) && (min1.ShapeType == BroadphaseNativeTypes.CAPSULE_SHAPE_PROXYTYPE))
{
CapsuleShape capsuleA = (CapsuleShape)min0;
CapsuleShape capsuleB = (CapsuleShape)min1;
btVector3 localScalingA = capsuleA.LocalScaling;
btVector3 localScalingB = capsuleB.LocalScaling;
float threshold = m_manifoldPtr.ContactBreakingThreshold;
float dist = capsuleCapsuleDistance(out normalOnB, out pointOnBWorld, capsuleA.HalfHeight, capsuleA.Radius,
capsuleB.HalfHeight, capsuleB.Radius, capsuleA.UpAxis, capsuleB.UpAxis,
body0.WorldTransform, body1.WorldTransform, threshold);
if (dist < threshold)
{
Debug.Assert(normalOnB.Length2 >= (BulletGlobal.SIMD_EPSILON * BulletGlobal.SIMD_EPSILON));
resultOut.addContactPoint(ref normalOnB, ref pointOnBWorld, dist);
}
resultOut.refreshContactPoints();
return;
}
#if USE_SEPDISTANCE_UTIL2
if (dispatchInfo.m_useConvexConservativeDistanceUtil)
{
m_sepDistance.updateSeparatingDistance(body0->getWorldTransform(),body1->getWorldTransform());
}
if (!dispatchInfo.m_useConvexConservativeDistanceUtil || m_sepDistance.getConservativeSeparatingDistance()<=0.f)
#endif //USE_SEPDISTANCE_UTIL2
{
ClosestPointInput input;
GjkPairDetector gjkPairDetector = new GjkPairDetector(min0, min1, m_simplexSolver, m_pdSolver);
//TODO: if (dispatchInfo.m_useContinuous)
gjkPairDetector.MinkowskiA = min0;
gjkPairDetector.MinkowskiB = min1;
#if USE_SEPDISTANCE_UTIL2
if (dispatchInfo.m_useConvexConservativeDistanceUtil)
{
input.m_maximumDistanceSquared = BT_LARGE_FLOAT;
} else
#endif //USE_SEPDISTANCE_UTIL2
{
input.m_maximumDistanceSquared = min0.Margin + min1.Margin + m_manifoldPtr.ContactBreakingThreshold;
input.m_maximumDistanceSquared *= input.m_maximumDistanceSquared;
}
//input.m_stackAlloc = dispatchInfo.m_stackAllocator;
input.m_transformA = body0.WorldTransform;
input.m_transformB = body1.WorldTransform;
gjkPairDetector.getClosestPoints(ref input, ref resultOut, dispatchInfo.m_debugDraw);
#if USE_SEPDISTANCE_UTIL2
btScalar sepDist = 0.f;
if (dispatchInfo.m_useConvexConservativeDistanceUtil)
{
sepDist = gjkPairDetector.getCachedSeparatingDistance();
if (sepDist>SIMD_EPSILON)
{
sepDist += dispatchInfo.m_convexConservativeDistanceThreshold;
//now perturbe directions to get multiple contact points
}
}
#endif //USE_SEPDISTANCE_UTIL2
//now perform 'm_numPerturbationIterations' collision queries with the perturbated collision objects
//perform perturbation when more then 'm_minimumPointsPerturbationThreshold' points
if (m_numPerturbationIterations != 0 && resultOut.PersistentManifold.NumContacts < m_minimumPointsPerturbationThreshold)
{
int i;
btVector3 v0, v1;
btVector3 sepNormalWorldSpace;
//sepNormalWorldSpace = gjkPairDetector.getCachedSeparatingAxis().normalized();
gjkPairDetector.getCachedSeparatingAxis().normalized(out sepNormalWorldSpace);
btVector3.PlaneSpace1(ref sepNormalWorldSpace, out v0, out v1);
bool perturbeA = true;
float angleLimit = 0.125f * BulletGlobal.SIMD_PI;
float perturbeAngle;
float radiusA = min0.getAngularMotionDisc();
float radiusB = min1.getAngularMotionDisc();
if (radiusA < radiusB)
{
perturbeAngle = PersistentManifold.gContactBreakingThreshold / radiusA;
perturbeA = true;
}
else
{
perturbeAngle = PersistentManifold.gContactBreakingThreshold / radiusB;
perturbeA = false;
}
if (perturbeAngle > angleLimit)
perturbeAngle = angleLimit;
btTransform unPerturbedTransform;
if (perturbeA)
{
unPerturbedTransform = input.m_transformA;
}
else
{
unPerturbedTransform = input.m_transformB;
}
for (i = 0; i < m_numPerturbationIterations; i++)
{
if (v0.Length2 > BulletGlobal.SIMD_EPSILON)
{
btQuaternion perturbeRot = new btQuaternion(v0, perturbeAngle);
float iterationAngle = i * (BulletGlobal.SIMD_2_PI / m_numPerturbationIterations);
btQuaternion rotq = new btQuaternion(sepNormalWorldSpace, iterationAngle);
if (perturbeA)
{
#region input.m_transformA.Basis = new btMatrix3x3(rotq.inverse() * perturbeRot * rotq) * body0.WorldTransform.Basis;
{
btMatrix3x3 temp = new btMatrix3x3(rotq.inverse() * perturbeRot * rotq);
btMatrix3x3.Multiply(ref temp, ref body0.WorldTransform.Basis, out input.m_transformA.Basis);
}
#endregion
input.m_transformB = body1.WorldTransform;
#if DEBUG
dispatchInfo.m_debugDraw.drawTransform(ref input.m_transformA, 10.0f);
#endif //DEBUG_CONTACTS
}
else
{
input.m_transformA = body0.WorldTransform;
#region input.m_transformB.Basis = new btMatrix3x3(rotq.inverse() * perturbeRot * rotq) * body1.WorldTransform.Basis;
{
btMatrix3x3 temp = new btMatrix3x3(rotq.inverse() * perturbeRot * rotq);
btMatrix3x3.Multiply(ref temp, ref body1.WorldTransform.Basis, out input.m_transformB.Basis);
}
#endregion
#if DEBUG
dispatchInfo.m_debugDraw.drawTransform(ref input.m_transformB, 10.0f);
#endif
}
PerturbedContactResult perturbedResultOut = new PerturbedContactResult(input.m_transformA, input.m_transformB, unPerturbedTransform, perturbeA, dispatchInfo.m_debugDraw);
gjkPairDetector.getClosestPoints(ref input, ref perturbedResultOut, ref resultOut, dispatchInfo.m_debugDraw);
}
}
}
#if USE_SEPDISTANCE_UTIL2
if (dispatchInfo.m_useConvexConservativeDistanceUtil && (sepDist>SIMD_EPSILON))
{
m_sepDistance.initSeparatingDistance(gjkPairDetector.getCachedSeparatingAxis(),sepDist,body0->getWorldTransform(),body1->getWorldTransform());
}
#endif //USE_SEPDISTANCE_UTIL2
}
if (m_ownManifold)
{
resultOut.refreshContactPoints();
}
}
/**@brief Return the dot product between this quaternion and another
* @param q The other quaternion */
public float dot(btQuaternion q)
{
return X * q.X + Y * q.Y + Z * q.Z + W * q.W;
}
/** @brief Set the matrix from a quaternion
* @param q The Quaternion to match */
public void setRotation(ref btQuaternion q)
{
float d = q.Length2;
Debug.Assert(d != 0.0f);
float s = 2.0f / d;
float xs = q.X * s, ys = q.Y * s, zs = q.Z * s;
float wx = q.W * xs, wy = q.W * ys, wz = q.W * zs;
float xx = q.X * xs, xy = q.X * ys, xz = q.X * zs;
float yy = q.Y * ys, yz = q.Y * zs, zz = q.Z * zs;
setValue(1.0f - (yy + zz), xy - wz, xz + wy,
xy + wz, 1.0f - (xx + zz), yz - wx,
xz - wy, yz + wx, 1.0f - (xx + yy));
}
/**@brief Get the matrix represented as a quaternion
* @param q The quaternion which will be set */
public void getRotation(out btQuaternion q)
{
StackPtr<float> temp = StackPtr<float>.Allocate(4);
try
{
float trace = el0.X + el1.Y + el2.Z;
//float[] temp = new float[4];
if (trace > 0.0f)
{
float s = (float)Math.Sqrt(trace + 1.0);
temp[3] = (s * 0.5f);
s = 0.5f / s;
temp[0] = ((el2.Y - el1.Z) * s);
temp[1] = ((el0.Z - el2.X) * s);
temp[2] = ((el1.X - el0.Y) * s);
}
else
{
int i = el0.X < el1.Y ?
(el1.Y < el2.Z ? 2 : 1) :
(el0.X < el2.Z ? 2 : 0);
int j = (i + 1) % 3;
int k = (i + 2) % 3;
float s = (float)Math.Sqrt(this[i][i] - this[j][j] - this[k][k] + 1.0f);
temp[i] = s * 0.5f;
s = 0.5f / s;
temp[3] = (this[k][j] - this[j][k]) * s;
temp[j] = (this[j][i] + this[i][j]) * s;
temp[k] = (this[k][i] + this[i][k]) * s;
}
q = new btQuaternion(temp[0], temp[1], temp[2], temp[3]);
}
finally
{
temp.Dispose();
}
}
public void collideSingleContact(btQuaternion perturbeRot, CollisionObject body0, CollisionObject body1, DispatcherInfo dispatchInfo, ref ManifoldResult resultOut)
{
CollisionObject convexObj = m_isSwapped ? body1 : body0;
CollisionObject planeObj = m_isSwapped ? body0 : body1;
ConvexShape convexShape = (ConvexShape)convexObj.CollisionShape;
StaticPlaneShape planeShape = (StaticPlaneShape)planeObj.CollisionShape;
bool hasCollision = false;
btVector3 planeNormal = planeShape.PlaneNormal;
float planeConstant = planeShape.PlaneConstant;
btTransform convexWorldTransform = convexObj.WorldTransform;
btTransform convexInPlaneTrans;
convexInPlaneTrans = planeObj.WorldTransform.inverse() * convexWorldTransform;
//now perturbe the convex-world transform
#region convexWorldTransform.Basis *= new btMatrix3x3(perturbeRot);
{
btMatrix3x3 temp1 = convexWorldTransform.Basis, temp2 = new btMatrix3x3(perturbeRot);
btMatrix3x3.Multiply(ref temp1, ref temp2, out convexWorldTransform.Basis);
}
#endregion
btTransform planeInConvex;
planeInConvex = convexWorldTransform.inverse() * planeObj.WorldTransform;
#region btVector3 vtx = convexShape.localGetSupportingVertex(planeInConvex.Basis * -planeNormal);
btVector3 vtx;
{
btVector3 temp, temp2;
temp2 = -planeNormal;
btMatrix3x3.Multiply(ref planeInConvex.Basis, ref temp2, out temp);
//vtx = convexShape.localGetSupportingVertex(temp);
convexShape.localGetSupportingVertex(ref temp, out vtx);
}
#endregion
btVector3 vtxInPlane = convexInPlaneTrans * vtx;
float distance = (planeNormal.dot(vtxInPlane) - planeConstant);
btVector3 vtxInPlaneProjected = vtxInPlane - distance * planeNormal;
btVector3 vtxInPlaneWorld = planeObj.WorldTransform * vtxInPlaneProjected;
hasCollision = distance < m_manifoldPtr.ContactBreakingThreshold;
resultOut.PersistentManifold = m_manifoldPtr;
if (hasCollision)
{
/// report a contact. internally this will be kept persistent, and contact reduction is done
btVector3 normalOnSurfaceB;// = planeObj.WorldTransform.Basis * planeNormal;
btMatrix3x3.Multiply(ref planeObj.WorldTransform.Basis, ref planeNormal, out normalOnSurfaceB);
btVector3 pOnB = vtxInPlaneWorld;
resultOut.addContactPoint(ref normalOnSurfaceB, ref pOnB, distance);
}
}