Files
bullet3/opencl/gpu_sat/kernels/primitiveContacts.cl
erwin coumans 358f4f97a2 add re-usable createGraphicsSphere method in GpuDemo.
introduce and use maxContactCapacity (needs to be fixed in various other contact kernels)
implement sphere versus trimesh
disable new/sequential GPU batching (only uses 1 thread in a warp, slow but works on NVIDIA/Apple OpenCL)
2013-04-04 17:54:45 -07:00

1070 lines
28 KiB
Common Lisp

#define TRIANGLE_NUM_CONVEX_FACES 5
#define SHAPE_CONVEX_HULL 3
#define SHAPE_PLANE 4
#define SHAPE_CONCAVE_TRIMESH 5
#define SHAPE_COMPOUND_OF_CONVEX_HULLS 6
#define SHAPE_SPHERE 7
#pragma OPENCL EXTENSION cl_amd_printf : enable
#pragma OPENCL EXTENSION cl_khr_local_int32_base_atomics : enable
#pragma OPENCL EXTENSION cl_khr_global_int32_base_atomics : enable
#pragma OPENCL EXTENSION cl_khr_local_int32_extended_atomics : enable
#pragma OPENCL EXTENSION cl_khr_global_int32_extended_atomics : enable
#ifdef cl_ext_atomic_counters_32
#pragma OPENCL EXTENSION cl_ext_atomic_counters_32 : enable
#else
#define counter32_t volatile __global int*
#endif
#define GET_GROUP_IDX get_group_id(0)
#define GET_LOCAL_IDX get_local_id(0)
#define GET_GLOBAL_IDX get_global_id(0)
#define GET_GROUP_SIZE get_local_size(0)
#define GET_NUM_GROUPS get_num_groups(0)
#define GROUP_LDS_BARRIER barrier(CLK_LOCAL_MEM_FENCE)
#define GROUP_MEM_FENCE mem_fence(CLK_LOCAL_MEM_FENCE)
#define AtomInc(x) atom_inc(&(x))
#define AtomInc1(x, out) out = atom_inc(&(x))
#define AppendInc(x, out) out = atomic_inc(x)
#define AtomAdd(x, value) atom_add(&(x), value)
#define AtomCmpxhg(x, cmp, value) atom_cmpxchg( &(x), cmp, value )
#define AtomXhg(x, value) atom_xchg ( &(x), value )
#define max2 max
#define min2 min
typedef unsigned int u32;
typedef struct
{
float4 m_worldPos[4];
float4 m_worldNormal; // w: m_nPoints
u32 m_coeffs;
u32 m_batchIdx;
int m_bodyAPtrAndSignBit;//x:m_bodyAPtr, y:m_bodyBPtr
int m_bodyBPtrAndSignBit;
} Contact4;
typedef struct
{
union
{
float4 m_min;
float m_minElems[4];
int m_minIndices[4];
};
union
{
float4 m_max;
float m_maxElems[4];
int m_maxIndices[4];
};
} btAabbCL;
///keep this in sync with btCollidable.h
typedef struct
{
int m_numChildShapes;
float m_radius;
int m_shapeType;
int m_shapeIndex;
} btCollidableGpu;
typedef struct
{
float4 m_childPosition;
float4 m_childOrientation;
int m_shapeIndex;
int m_unused0;
int m_unused1;
int m_unused2;
} btGpuChildShape;
#define GET_NPOINTS(x) (x).m_worldNormal.w
typedef struct
{
float4 m_pos;
float4 m_quat;
float4 m_linVel;
float4 m_angVel;
u32 m_collidableIdx;
float m_invMass;
float m_restituitionCoeff;
float m_frictionCoeff;
} BodyData;
typedef struct
{
float4 m_localCenter;
float4 m_extents;
float4 mC;
float4 mE;
float m_radius;
int m_faceOffset;
int m_numFaces;
int m_numVertices;
int m_vertexOffset;
int m_uniqueEdgesOffset;
int m_numUniqueEdges;
int m_unused;
} ConvexPolyhedronCL;
typedef struct
{
float4 m_plane;
int m_indexOffset;
int m_numIndices;
} btGpuFace;
#define SELECT_UINT4( b, a, condition ) select( b,a,condition )
#define make_float4 (float4)
#define make_float2 (float2)
#define make_uint4 (uint4)
#define make_int4 (int4)
#define make_uint2 (uint2)
#define make_int2 (int2)
__inline
float fastDiv(float numerator, float denominator)
{
return native_divide(numerator, denominator);
// return numerator/denominator;
}
__inline
float4 fastDiv4(float4 numerator, float4 denominator)
{
return native_divide(numerator, denominator);
}
__inline
float4 cross3(float4 a, float4 b)
{
return cross(a,b);
}
//#define dot3F4 dot
__inline
float dot3F4(float4 a, float4 b)
{
float4 a1 = make_float4(a.xyz,0.f);
float4 b1 = make_float4(b.xyz,0.f);
return dot(a1, b1);
}
__inline
float4 fastNormalize4(float4 v)
{
return fast_normalize(v);
}
///////////////////////////////////////
// Quaternion
///////////////////////////////////////
typedef float4 Quaternion;
__inline
Quaternion qtMul(Quaternion a, Quaternion b);
__inline
Quaternion qtNormalize(Quaternion in);
__inline
float4 qtRotate(Quaternion q, float4 vec);
__inline
Quaternion qtInvert(Quaternion q);
__inline
Quaternion qtMul(Quaternion a, Quaternion b)
{
Quaternion ans;
ans = cross3( a, b );
ans += a.w*b+b.w*a;
// ans.w = a.w*b.w - (a.x*b.x+a.y*b.y+a.z*b.z);
ans.w = a.w*b.w - dot3F4(a, b);
return ans;
}
__inline
Quaternion qtNormalize(Quaternion in)
{
return fastNormalize4(in);
// in /= length( in );
// return in;
}
__inline
float4 qtRotate(Quaternion q, float4 vec)
{
Quaternion qInv = qtInvert( q );
float4 vcpy = vec;
vcpy.w = 0.f;
float4 out = qtMul(qtMul(q,vcpy),qInv);
return out;
}
__inline
Quaternion qtInvert(Quaternion q)
{
return (Quaternion)(-q.xyz, q.w);
}
__inline
float4 qtInvRotate(const Quaternion q, float4 vec)
{
return qtRotate( qtInvert( q ), vec );
}
__inline
float4 transform(const float4* p, const float4* translation, const Quaternion* orientation)
{
return qtRotate( *orientation, *p ) + (*translation);
}
void trInverse(float4 translationIn, Quaternion orientationIn,
float4* translationOut, Quaternion* orientationOut)
{
*orientationOut = qtInvert(orientationIn);
*translationOut = qtRotate(*orientationOut, -translationIn);
}
void trMul(float4 translationA, Quaternion orientationA,
float4 translationB, Quaternion orientationB,
float4* translationOut, Quaternion* orientationOut)
{
*orientationOut = qtMul(orientationA,orientationB);
*translationOut = transform(&translationB,&translationA,&orientationA);
}
__inline
float4 normalize3(const float4 a)
{
float4 n = make_float4(a.x, a.y, a.z, 0.f);
return fastNormalize4( n );
}
__inline float4 lerp3(const float4 a,const float4 b, float t)
{
return make_float4( a.x + (b.x - a.x) * t,
a.y + (b.y - a.y) * t,
a.z + (b.z - a.z) * t,
0.f);
}
float signedDistanceFromPointToPlane(float4 point, float4 planeEqn, float4* closestPointOnFace)
{
float4 n = (float4)(planeEqn.x, planeEqn.y, planeEqn.z, 0);
float dist = dot3F4(n, point) + planeEqn.w;
*closestPointOnFace = point - dist * n;
return dist;
}
inline bool IsPointInPolygon(float4 p,
const btGpuFace* face,
__global const float4* baseVertex,
__global const int* convexIndices,
float4* out)
{
float4 a;
float4 b;
float4 ab;
float4 ap;
float4 v;
float4 plane = make_float4(face->m_plane.x,face->m_plane.y,face->m_plane.z,0.f);
if (face->m_numIndices<2)
return false;
float4 v0 = baseVertex[convexIndices[face->m_indexOffset + face->m_numIndices-1]];
b = v0;
for(unsigned i=0; i != face->m_numIndices; ++i)
{
a = b;
float4 vi = baseVertex[convexIndices[face->m_indexOffset + i]];
b = vi;
ab = b-a;
ap = p-a;
v = cross3(ab,plane);
if (dot(ap, v) > 0.f)
{
float ab_m2 = dot(ab, ab);
float rt = ab_m2 != 0.f ? dot(ab, ap) / ab_m2 : 0.f;
if (rt <= 0.f)
{
*out = a;
}
else if (rt >= 1.f)
{
*out = b;
}
else
{
float s = 1.f - rt;
out[0].x = s * a.x + rt * b.x;
out[0].y = s * a.y + rt * b.y;
out[0].z = s * a.z + rt * b.z;
}
return false;
}
}
return true;
}
void computeContactSphereConvex(int pairIndex,
int bodyIndexA, int bodyIndexB,
int collidableIndexA, int collidableIndexB,
__global const BodyData* rigidBodies,
__global const btCollidableGpu* collidables,
__global const ConvexPolyhedronCL* convexShapes,
__global const float4* convexVertices,
__global const int* convexIndices,
__global const btGpuFace* faces,
__global Contact4* restrict globalContactsOut,
counter32_t nGlobalContactsOut,
int maxContactCapacity,
float4 spherePos2,
float radius,
float4 pos,
float4 quat
)
{
float4 invPos;
float4 invOrn;
trInverse(pos,quat, &invPos,&invOrn);
float4 spherePos = transform(&spherePos2,&invPos,&invOrn);
int shapeIndex = collidables[collidableIndexB].m_shapeIndex;
int numFaces = convexShapes[shapeIndex].m_numFaces;
float4 closestPnt = (float4)(0, 0, 0, 0);
float4 hitNormalWorld = (float4)(0, 0, 0, 0);
float minDist = -1000000.f;
bool bCollide = true;
for ( int f = 0; f < numFaces; f++ )
{
btGpuFace face = faces[convexShapes[shapeIndex].m_faceOffset+f];
// set up a plane equation
float4 planeEqn;
float4 n1 = face.m_plane;
n1.w = 0.f;
planeEqn = n1;
planeEqn.w = face.m_plane.w;
// compute a signed distance from the vertex in cloth to the face of rigidbody.
float4 pntReturn;
float dist = signedDistanceFromPointToPlane(spherePos, planeEqn, &pntReturn);
// If the distance is positive, the plane is a separating plane.
if ( dist > radius )
{
bCollide = false;
break;
}
if (dist>0)
{
//might hit an edge or vertex
float4 out;
float4 zeroPos = make_float4(0,0,0,0);
bool isInPoly = IsPointInPolygon(spherePos,
&face,
&convexVertices[convexShapes[shapeIndex].m_vertexOffset],
convexIndices,
&out);
if (isInPoly)
{
if (dist>minDist)
{
minDist = dist;
closestPnt = pntReturn;
hitNormalWorld = planeEqn;
}
} else
{
float4 tmp = spherePos-out;
float l2 = dot(tmp,tmp);
if (l2<radius*radius)
{
dist = sqrt(l2);
if (dist>minDist)
{
minDist = dist;
closestPnt = out;
hitNormalWorld = tmp/dist;
}
} else
{
bCollide = false;
break;
}
}
} else
{
if ( dist > minDist )
{
minDist = dist;
closestPnt = pntReturn;
hitNormalWorld.xyz = planeEqn.xyz;
}
}
}
if (bCollide && minDist > -10000)
{
float4 normalOnSurfaceB1 = qtRotate(quat,-hitNormalWorld);
float4 pOnB1 = transform(&closestPnt,&pos,&quat);
float actualDepth = minDist-radius;
if (actualDepth<=0.f)
{
pOnB1.w = actualDepth;
int dstIdx;
AppendInc( nGlobalContactsOut, dstIdx );
if (1)//dstIdx < maxContactCapacity)
{
__global Contact4* c = &globalContactsOut[dstIdx];
c->m_worldNormal = normalOnSurfaceB1;
c->m_coeffs = (u32)(0.f*0xffff) | ((u32)(0.7f*0xffff)<<16);
c->m_batchIdx = pairIndex;
c->m_bodyAPtrAndSignBit = rigidBodies[bodyIndexA].m_invMass==0?-bodyIndexA:bodyIndexA;
c->m_bodyBPtrAndSignBit = rigidBodies[bodyIndexB].m_invMass==0?-bodyIndexB:bodyIndexB;
c->m_worldPos[0] = pOnB1;
GET_NPOINTS(*c) = 1;
}
}
}//if (hasCollision)
}
void computeContactPlaneConvex(int pairIndex,
int bodyIndexA, int bodyIndexB,
int collidableIndexA, int collidableIndexB,
__global const BodyData* rigidBodies,
__global const btCollidableGpu* collidables,
__global const btGpuFace* faces,
__global Contact4* restrict globalContactsOut,
counter32_t nGlobalContactsOut,
int maxContactCapacity)
{
float4 planeEq = faces[collidables[collidableIndexA].m_shapeIndex].m_plane;
float radius = collidables[collidableIndexB].m_radius;
float4 posA1 = rigidBodies[bodyIndexA].m_pos;
float4 ornA1 = rigidBodies[bodyIndexA].m_quat;
float4 posB1 = rigidBodies[bodyIndexB].m_pos;
float4 ornB1 = rigidBodies[bodyIndexB].m_quat;
bool hasCollision = false;
float4 planeNormal1 = make_float4(planeEq.x,planeEq.y,planeEq.z,0.f);
float planeConstant = planeEq.w;
float4 convexInPlaneTransPos1; Quaternion convexInPlaneTransOrn1;
{
float4 invPosA;Quaternion invOrnA;
trInverse(posA1,ornA1,&invPosA,&invOrnA);
trMul(invPosA,invOrnA,posB1,ornB1,&convexInPlaneTransPos1,&convexInPlaneTransOrn1);
}
float4 planeInConvexPos1; Quaternion planeInConvexOrn1;
{
float4 invPosB;Quaternion invOrnB;
trInverse(posB1,ornB1,&invPosB,&invOrnB);
trMul(invPosB,invOrnB,posA1,ornA1,&planeInConvexPos1,&planeInConvexOrn1);
}
float4 vtx1 = qtRotate(planeInConvexOrn1,-planeNormal1)*radius;
float4 vtxInPlane1 = transform(&vtx1,&convexInPlaneTransPos1,&convexInPlaneTransOrn1);
float distance = dot3F4(planeNormal1,vtxInPlane1) - planeConstant;
hasCollision = distance < 0.f;//m_manifoldPtr->getContactBreakingThreshold();
if (hasCollision)
{
float4 vtxInPlaneProjected1 = vtxInPlane1 - distance*planeNormal1;
float4 vtxInPlaneWorld1 = transform(&vtxInPlaneProjected1,&posA1,&ornA1);
float4 normalOnSurfaceB1 = qtRotate(ornA1,planeNormal1);
float4 pOnB1 = vtxInPlaneWorld1+normalOnSurfaceB1*distance;
pOnB1.w = distance;
int dstIdx;
AppendInc( nGlobalContactsOut, dstIdx );
if (dstIdx < maxContactCapacity)
{
__global Contact4* c = &globalContactsOut[dstIdx];
c->m_worldNormal = normalOnSurfaceB1;
c->m_coeffs = (u32)(0.f*0xffff) | ((u32)(0.7f*0xffff)<<16);
c->m_batchIdx = pairIndex;
c->m_bodyAPtrAndSignBit = rigidBodies[bodyIndexA].m_invMass==0?-bodyIndexA:bodyIndexA;
c->m_bodyBPtrAndSignBit = rigidBodies[bodyIndexB].m_invMass==0?-bodyIndexB:bodyIndexB;
c->m_worldPos[0] = pOnB1;
GET_NPOINTS(*c) = 1;
}//if (dstIdx < numPairs)
}//if (hasCollision)
}
__kernel void primitiveContactsKernel( __global const int2* pairs,
__global const BodyData* rigidBodies,
__global const btCollidableGpu* collidables,
__global const ConvexPolyhedronCL* convexShapes,
__global const float4* vertices,
__global const float4* uniqueEdges,
__global const btGpuFace* faces,
__global const int* indices,
__global Contact4* restrict globalContactsOut,
counter32_t nGlobalContactsOut,
int numPairs, int maxContactCapacity)
{
int i = get_global_id(0);
int pairIndex = i;
float4 worldVertsB1[64];
float4 worldVertsB2[64];
int capacityWorldVerts = 64;
float4 localContactsOut[64];
int localContactCapacity=64;
float minDist = -1e30f;
float maxDist = 0.02f;
if (i<numPairs)
{
int bodyIndexA = pairs[i].x;
int bodyIndexB = pairs[i].y;
int collidableIndexA = rigidBodies[bodyIndexA].m_collidableIdx;
int collidableIndexB = rigidBodies[bodyIndexB].m_collidableIdx;
if (collidables[collidableIndexA].m_shapeType == SHAPE_SPHERE &&
collidables[collidableIndexB].m_shapeType == SHAPE_PLANE)
{
computeContactPlaneConvex( pairIndex, bodyIndexB,bodyIndexA, collidableIndexB,collidableIndexA,
rigidBodies,collidables,faces, globalContactsOut, nGlobalContactsOut,maxContactCapacity);
return;
}
if (collidables[collidableIndexA].m_shapeType == SHAPE_PLANE &&
collidables[collidableIndexB].m_shapeType == SHAPE_SPHERE)
{
computeContactPlaneConvex(pairIndex, bodyIndexA, bodyIndexB, collidableIndexA, collidableIndexB,
rigidBodies,collidables,faces, globalContactsOut, nGlobalContactsOut,maxContactCapacity);
return;
}
if (collidables[collidableIndexA].m_shapeType == SHAPE_SPHERE &&
collidables[collidableIndexB].m_shapeType == SHAPE_CONVEX_HULL)
{
float4 spherePos = rigidBodies[bodyIndexA].m_pos;
float sphereRadius = collidables[collidableIndexA].m_radius;
float4 convexPos = rigidBodies[bodyIndexB].m_pos;
float4 convexOrn = rigidBodies[bodyIndexB].m_quat;
computeContactSphereConvex(pairIndex, bodyIndexA, bodyIndexB, collidableIndexA, collidableIndexB,
rigidBodies,collidables,convexShapes,vertices,indices,faces, globalContactsOut, nGlobalContactsOut,maxContactCapacity,
spherePos,sphereRadius,convexPos,convexOrn);
return;
}
if (collidables[collidableIndexA].m_shapeType == SHAPE_CONVEX_HULL &&
collidables[collidableIndexB].m_shapeType == SHAPE_SPHERE)
{
float4 spherePos = rigidBodies[bodyIndexB].m_pos;
float sphereRadius = collidables[collidableIndexB].m_radius;
float4 convexPos = rigidBodies[bodyIndexA].m_pos;
float4 convexOrn = rigidBodies[bodyIndexA].m_quat;
computeContactSphereConvex(pairIndex, bodyIndexB, bodyIndexA, collidableIndexB, collidableIndexA,
rigidBodies,collidables,convexShapes,vertices,indices,faces, globalContactsOut, nGlobalContactsOut,maxContactCapacity,
spherePos,sphereRadius,convexPos,convexOrn);
return;
}
if (collidables[collidableIndexA].m_shapeType == SHAPE_SPHERE &&
collidables[collidableIndexB].m_shapeType == SHAPE_SPHERE)
{
//sphere-sphere
float radiusA = collidables[collidableIndexA].m_radius;
float radiusB = collidables[collidableIndexB].m_radius;
float4 posA = rigidBodies[bodyIndexA].m_pos;
float4 posB = rigidBodies[bodyIndexB].m_pos;
float4 diff = posA-posB;
float len = length(diff);
///iff distance positive, don't generate a new contact
if ( len <= (radiusA+radiusB))
{
///distance (negative means penetration)
float dist = len - (radiusA+radiusB);
float4 normalOnSurfaceB = make_float4(1.f,0.f,0.f,0.f);
if (len > 0.00001)
{
normalOnSurfaceB = diff / len;
}
float4 contactPosB = posB + normalOnSurfaceB*radiusB;
contactPosB.w = dist;
int dstIdx;
AppendInc( nGlobalContactsOut, dstIdx );
if (dstIdx < maxContactCapacity)
{
__global Contact4* c = &globalContactsOut[dstIdx];
c->m_worldNormal = -normalOnSurfaceB;
c->m_coeffs = (u32)(0.f*0xffff) | ((u32)(0.7f*0xffff)<<16);
c->m_batchIdx = pairIndex;
int bodyA = pairs[pairIndex].x;
int bodyB = pairs[pairIndex].y;
c->m_bodyAPtrAndSignBit = rigidBodies[bodyA].m_invMass==0?-bodyA:bodyA;
c->m_bodyBPtrAndSignBit = rigidBodies[bodyB].m_invMass==0?-bodyB:bodyB;
c->m_worldPos[0] = contactPosB;
GET_NPOINTS(*c) = 1;
}//if (dstIdx < numPairs)
}//if ( len <= (radiusA+radiusB))
return;
}//SHAPE_SPHERE SHAPE_SPHERE
}// if (i<numPairs)
}
// work-in-progress
__kernel void processCompoundPairsPrimitivesKernel( __global const int4* gpuCompoundPairs,
__global const BodyData* rigidBodies,
__global const btCollidableGpu* collidables,
__global const ConvexPolyhedronCL* convexShapes,
__global const float4* vertices,
__global const float4* uniqueEdges,
__global const btGpuFace* faces,
__global const int* indices,
__global btAabbCL* aabbs,
__global const btGpuChildShape* gpuChildShapes,
__global Contact4* restrict globalContactsOut,
counter32_t nGlobalContactsOut,
int numCompoundPairs, int maxContactCapacity
)
{
int i = get_global_id(0);
if (i<numCompoundPairs)
{
int bodyIndexA = gpuCompoundPairs[i].x;
int bodyIndexB = gpuCompoundPairs[i].y;
int childShapeIndexA = gpuCompoundPairs[i].z;
int childShapeIndexB = gpuCompoundPairs[i].w;
int collidableIndexA = -1;
int collidableIndexB = -1;
float4 ornA = rigidBodies[bodyIndexA].m_quat;
float4 posA = rigidBodies[bodyIndexA].m_pos;
float4 ornB = rigidBodies[bodyIndexB].m_quat;
float4 posB = rigidBodies[bodyIndexB].m_pos;
if (childShapeIndexA >= 0)
{
collidableIndexA = gpuChildShapes[childShapeIndexA].m_shapeIndex;
float4 childPosA = gpuChildShapes[childShapeIndexA].m_childPosition;
float4 childOrnA = gpuChildShapes[childShapeIndexA].m_childOrientation;
float4 newPosA = qtRotate(ornA,childPosA)+posA;
float4 newOrnA = qtMul(ornA,childOrnA);
posA = newPosA;
ornA = newOrnA;
} else
{
collidableIndexA = rigidBodies[bodyIndexA].m_collidableIdx;
}
if (childShapeIndexB>=0)
{
collidableIndexB = gpuChildShapes[childShapeIndexB].m_shapeIndex;
float4 childPosB = gpuChildShapes[childShapeIndexB].m_childPosition;
float4 childOrnB = gpuChildShapes[childShapeIndexB].m_childOrientation;
float4 newPosB = transform(&childPosB,&posB,&ornB);
float4 newOrnB = qtMul(ornB,childOrnB);
posB = newPosB;
ornB = newOrnB;
} else
{
collidableIndexB = rigidBodies[bodyIndexB].m_collidableIdx;
}
int shapeIndexA = collidables[collidableIndexA].m_shapeIndex;
int shapeIndexB = collidables[collidableIndexB].m_shapeIndex;
int shapeTypeA = collidables[collidableIndexA].m_shapeType;
int shapeTypeB = collidables[collidableIndexB].m_shapeType;
int pairIndex = i;
if ((shapeTypeA == SHAPE_CONVEX_HULL) && (shapeTypeB == SHAPE_SPHERE))
{
float4 spherePos = rigidBodies[bodyIndexB].m_pos;
float sphereRadius = collidables[collidableIndexB].m_radius;
float4 convexPos = posA;
float4 convexOrn = ornA;
computeContactSphereConvex(pairIndex, bodyIndexB, bodyIndexA , collidableIndexB,collidableIndexA,
rigidBodies,collidables,convexShapes,vertices,indices,faces, globalContactsOut, nGlobalContactsOut,maxContactCapacity,
spherePos,sphereRadius,convexPos,convexOrn);
return;
}
if ((shapeTypeA == SHAPE_SPHERE) && (shapeTypeB == SHAPE_CONVEX_HULL))
{
float4 spherePos = rigidBodies[bodyIndexA].m_pos;
float sphereRadius = collidables[collidableIndexA].m_radius;
float4 convexPos = posB;
float4 convexOrn = ornB;
computeContactSphereConvex(pairIndex, bodyIndexA, bodyIndexB, collidableIndexA, collidableIndexB,
rigidBodies,collidables,convexShapes,vertices,indices,faces, globalContactsOut, nGlobalContactsOut,maxContactCapacity,
spherePos,sphereRadius,convexPos,convexOrn);
return;
}
}// if (i<numCompoundPairs)
}
bool pointInTriangle(const float4* vertices, const float4* normal, float4 *p )
{
const float4* p1 = &vertices[0];
const float4* p2 = &vertices[1];
const float4* p3 = &vertices[2];
float4 edge1; edge1 = (*p2 - *p1);
float4 edge2; edge2 = ( *p3 - *p2 );
float4 edge3; edge3 = ( *p1 - *p3 );
float4 p1_to_p; p1_to_p = ( *p - *p1 );
float4 p2_to_p; p2_to_p = ( *p - *p2 );
float4 p3_to_p; p3_to_p = ( *p - *p3 );
float4 edge1_normal; edge1_normal = ( cross(edge1,*normal));
float4 edge2_normal; edge2_normal = ( cross(edge2,*normal));
float4 edge3_normal; edge3_normal = ( cross(edge3,*normal));
float r1, r2, r3;
r1 = dot(edge1_normal,p1_to_p );
r2 = dot(edge2_normal,p2_to_p );
r3 = dot(edge3_normal,p3_to_p );
if ( r1 > 0 && r2 > 0 && r3 > 0 )
return true;
if ( r1 <= 0 && r2 <= 0 && r3 <= 0 )
return true;
return false;
}
float segmentSqrDistance(float4 from, float4 to,float4 p, float4* nearest)
{
float4 diff = p - from;
float4 v = to - from;
float t = dot(v,diff);
if (t > 0)
{
float dotVV = dot(v,v);
if (t < dotVV)
{
t /= dotVV;
diff -= t*v;
} else
{
t = 1;
diff -= v;
}
} else
{
t = 0;
}
*nearest = from + t*v;
return dot(diff,diff);
}
void computeContactSphereTriangle(int pairIndex,
int bodyIndexA, int bodyIndexB,
int collidableIndexA, int collidableIndexB,
__global const BodyData* rigidBodies,
__global const btCollidableGpu* collidables,
const float4* triangleVertices,
__global Contact4* restrict globalContactsOut,
counter32_t nGlobalContactsOut,
int maxContactCapacity,
float4 spherePos2,
float radius,
float4 pos,
float4 quat
)
{
float4 invPos;
float4 invOrn;
trInverse(pos,quat, &invPos,&invOrn);
float4 spherePos = transform(&spherePos2,&invPos,&invOrn);
int numFaces = 3;
float4 closestPnt = (float4)(0, 0, 0, 0);
float4 hitNormalWorld = (float4)(0, 0, 0, 0);
float minDist = -1000000.f;
bool bCollide = true;
//////////////////////////////////////
float4 sphereCenter;
sphereCenter = spherePos;
const float4* vertices = triangleVertices;
float contactBreakingThreshold = 0.f;//todo?
float radiusWithThreshold = radius + contactBreakingThreshold;
float4 edge10;
edge10 = vertices[1]-vertices[0];
edge10.w = 0.f;//is this needed?
float4 edge20;
edge20 = vertices[2]-vertices[0];
edge20.w = 0.f;//is this needed?
float4 normal = cross3(edge10,edge20);
normal = normalize(normal);
float4 p1ToCenter;
p1ToCenter = sphereCenter - vertices[0];
float distanceFromPlane = dot(p1ToCenter,normal);
if (distanceFromPlane < 0.f)
{
//triangle facing the other way
distanceFromPlane *= -1.f;
normal *= -1.f;
}
hitNormalWorld = normal;
bool isInsideContactPlane = distanceFromPlane < radiusWithThreshold;
// Check for contact / intersection
bool hasContact = false;
float4 contactPoint;
if (isInsideContactPlane)
{
if (pointInTriangle(vertices,&normal, &sphereCenter))
{
// Inside the contact wedge - touches a point on the shell plane
hasContact = true;
contactPoint = sphereCenter - normal*distanceFromPlane;
} else {
// Could be inside one of the contact capsules
float contactCapsuleRadiusSqr = radiusWithThreshold*radiusWithThreshold;
float4 nearestOnEdge;
int numEdges = 3;
for (int i = 0; i < numEdges; i++)
{
float4 pa =vertices[i];
float4 pb = vertices[(i+1)%3];
float distanceSqr = segmentSqrDistance(pa,pb,sphereCenter, &nearestOnEdge);
if (distanceSqr < contactCapsuleRadiusSqr)
{
// Yep, we're inside a capsule
hasContact = true;
contactPoint = nearestOnEdge;
}
}
}
}
if (hasContact)
{
closestPnt = contactPoint;
float4 contactToCenter = sphereCenter - contactPoint;
minDist = length(contactToCenter);
if (minDist>0.f)
{
hitNormalWorld = normalize(contactToCenter);//*(1./minDist);
}
bCollide = true;
}
/////////////////////////////////////
if (bCollide && minDist > -10000)
{
float4 normalOnSurfaceB1 = qtRotate(quat,-hitNormalWorld);
float4 pOnB1 = transform(&closestPnt,&pos,&quat);
float actualDepth = minDist-radius;
if (actualDepth<=0.f)
{
pOnB1.w = actualDepth;
int dstIdx;
AppendInc( nGlobalContactsOut, dstIdx );
if (dstIdx < maxContactCapacity)
{
__global Contact4* c = &globalContactsOut[dstIdx];
c->m_worldNormal = normalOnSurfaceB1;
c->m_coeffs = (u32)(0.f*0xffff) | ((u32)(0.7f*0xffff)<<16);
c->m_batchIdx = pairIndex;
c->m_bodyAPtrAndSignBit = rigidBodies[bodyIndexA].m_invMass==0?-bodyIndexA:bodyIndexA;
c->m_bodyBPtrAndSignBit = rigidBodies[bodyIndexB].m_invMass==0?-bodyIndexB:bodyIndexB;
c->m_worldPos[0] = pOnB1;
GET_NPOINTS(*c) = 1;
}
}
}//if (hasCollision)
}
// work-in-progress
__kernel void findConcaveSphereContactsKernel( __global int4* concavePairs,
__global const BodyData* rigidBodies,
__global const btCollidableGpu* collidables,
__global const ConvexPolyhedronCL* convexShapes,
__global const float4* vertices,
__global const float4* uniqueEdges,
__global const btGpuFace* faces,
__global const int* indices,
__global btAabbCL* aabbs,
__global Contact4* restrict globalContactsOut,
counter32_t nGlobalContactsOut,
int numConcavePairs, int maxContactCapacity
)
{
int i = get_global_id(0);
if (i>=numConcavePairs)
return;
int pairIdx = i;
int bodyIndexA = concavePairs[i].x;
int bodyIndexB = concavePairs[i].y;
int collidableIndexA = rigidBodies[bodyIndexA].m_collidableIdx;
int collidableIndexB = rigidBodies[bodyIndexB].m_collidableIdx;
int shapeIndexA = collidables[collidableIndexA].m_shapeIndex;
int shapeIndexB = collidables[collidableIndexB].m_shapeIndex;
if (collidables[collidableIndexB].m_shapeType==SHAPE_SPHERE)
{
int f = concavePairs[i].z;
btGpuFace face = faces[convexShapes[shapeIndexA].m_faceOffset+f];
float4 verticesA[3];
for (int i=0;i<3;i++)
{
int index = indices[face.m_indexOffset+i];
float4 vert = vertices[convexShapes[shapeIndexA].m_vertexOffset+index];
verticesA[i] = vert;
}
float4 spherePos = rigidBodies[bodyIndexB].m_pos;
float sphereRadius = collidables[collidableIndexB].m_radius;
float4 convexPos = rigidBodies[bodyIndexA].m_pos;
float4 convexOrn = rigidBodies[bodyIndexA].m_quat;
computeContactSphereTriangle(i, bodyIndexB, bodyIndexA, collidableIndexB, collidableIndexA,
rigidBodies,collidables,
verticesA,
globalContactsOut, nGlobalContactsOut,maxContactCapacity,
spherePos,sphereRadius,convexPos,convexOrn);
return;
}
}