summaryrefslogtreecommitdiff
path: root/thirdparty/bullet/Bullet3Collision/NarrowPhaseCollision/shared/b3MprPenetration.h
diff options
context:
space:
mode:
Diffstat (limited to 'thirdparty/bullet/Bullet3Collision/NarrowPhaseCollision/shared/b3MprPenetration.h')
-rw-r--r--thirdparty/bullet/Bullet3Collision/NarrowPhaseCollision/shared/b3MprPenetration.h920
1 files changed, 920 insertions, 0 deletions
diff --git a/thirdparty/bullet/Bullet3Collision/NarrowPhaseCollision/shared/b3MprPenetration.h b/thirdparty/bullet/Bullet3Collision/NarrowPhaseCollision/shared/b3MprPenetration.h
new file mode 100644
index 0000000000..6c3ad7c9dd
--- /dev/null
+++ b/thirdparty/bullet/Bullet3Collision/NarrowPhaseCollision/shared/b3MprPenetration.h
@@ -0,0 +1,920 @@
+
+/***
+ * ---------------------------------
+ * Copyright (c)2012 Daniel Fiser <danfis@danfis.cz>
+ *
+ * This file was ported from mpr.c file, part of libccd.
+ * The Minkoski Portal Refinement implementation was ported
+ * to OpenCL by Erwin Coumans for the Bullet 3 Physics library.
+ * at http://github.com/erwincoumans/bullet3
+ *
+ * Distributed under the OSI-approved BSD License (the "License");
+ * see <http://www.opensource.org/licenses/bsd-license.php>.
+ * This software is distributed WITHOUT ANY WARRANTY; without even the
+ * implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the License for more information.
+ */
+
+
+
+
+#ifndef B3_MPR_PENETRATION_H
+#define B3_MPR_PENETRATION_H
+
+#include "Bullet3Common/shared/b3PlatformDefinitions.h"
+#include "Bullet3Common/shared/b3Float4.h"
+#include "Bullet3Collision/NarrowPhaseCollision/shared/b3RigidBodyData.h"
+#include "Bullet3Collision/NarrowPhaseCollision/shared/b3ConvexPolyhedronData.h"
+#include "Bullet3Collision/NarrowPhaseCollision/shared/b3Collidable.h"
+
+
+
+
+#ifdef __cplusplus
+#define B3_MPR_SQRT sqrtf
+#else
+#define B3_MPR_SQRT sqrt
+#endif
+#define B3_MPR_FMIN(x, y) ((x) < (y) ? (x) : (y))
+#define B3_MPR_FABS fabs
+
+#define B3_MPR_TOLERANCE 1E-6f
+#define B3_MPR_MAX_ITERATIONS 1000
+
+struct _b3MprSupport_t
+{
+ b3Float4 v; //!< Support point in minkowski sum
+ b3Float4 v1; //!< Support point in obj1
+ b3Float4 v2; //!< Support point in obj2
+};
+typedef struct _b3MprSupport_t b3MprSupport_t;
+
+struct _b3MprSimplex_t
+{
+ b3MprSupport_t ps[4];
+ int last; //!< index of last added point
+};
+typedef struct _b3MprSimplex_t b3MprSimplex_t;
+
+inline b3MprSupport_t* b3MprSimplexPointW(b3MprSimplex_t *s, int idx)
+{
+ return &s->ps[idx];
+}
+
+inline void b3MprSimplexSetSize(b3MprSimplex_t *s, int size)
+{
+ s->last = size - 1;
+}
+
+
+inline int b3MprSimplexSize(const b3MprSimplex_t *s)
+{
+ return s->last + 1;
+}
+
+
+inline const b3MprSupport_t* b3MprSimplexPoint(const b3MprSimplex_t* s, int idx)
+{
+ // here is no check on boundaries
+ return &s->ps[idx];
+}
+
+inline void b3MprSupportCopy(b3MprSupport_t *d, const b3MprSupport_t *s)
+{
+ *d = *s;
+}
+
+inline void b3MprSimplexSet(b3MprSimplex_t *s, size_t pos, const b3MprSupport_t *a)
+{
+ b3MprSupportCopy(s->ps + pos, a);
+}
+
+
+inline void b3MprSimplexSwap(b3MprSimplex_t *s, size_t pos1, size_t pos2)
+{
+ b3MprSupport_t supp;
+
+ b3MprSupportCopy(&supp, &s->ps[pos1]);
+ b3MprSupportCopy(&s->ps[pos1], &s->ps[pos2]);
+ b3MprSupportCopy(&s->ps[pos2], &supp);
+}
+
+
+inline int b3MprIsZero(float val)
+{
+ return B3_MPR_FABS(val) < FLT_EPSILON;
+}
+
+
+
+inline int b3MprEq(float _a, float _b)
+{
+ float ab;
+ float a, b;
+
+ ab = B3_MPR_FABS(_a - _b);
+ if (B3_MPR_FABS(ab) < FLT_EPSILON)
+ return 1;
+
+ a = B3_MPR_FABS(_a);
+ b = B3_MPR_FABS(_b);
+ if (b > a){
+ return ab < FLT_EPSILON * b;
+ }else{
+ return ab < FLT_EPSILON * a;
+ }
+}
+
+
+inline int b3MprVec3Eq(const b3Float4* a, const b3Float4 *b)
+{
+ return b3MprEq((*a).x, (*b).x)
+ && b3MprEq((*a).y, (*b).y)
+ && b3MprEq((*a).z, (*b).z);
+}
+
+
+
+inline b3Float4 b3LocalGetSupportVertex(b3Float4ConstArg supportVec,__global const b3ConvexPolyhedronData_t* hull, b3ConstArray(b3Float4) verticesA)
+{
+ b3Float4 supVec = b3MakeFloat4(0,0,0,0);
+ float maxDot = -B3_LARGE_FLOAT;
+
+ if( 0 < hull->m_numVertices )
+ {
+ const b3Float4 scaled = supportVec;
+ int index = b3MaxDot(scaled, &verticesA[hull->m_vertexOffset], hull->m_numVertices, &maxDot);
+ return verticesA[hull->m_vertexOffset+index];
+ }
+
+ return supVec;
+
+}
+
+
+B3_STATIC void b3MprConvexSupport(int pairIndex,int bodyIndex, b3ConstArray(b3RigidBodyData_t) cpuBodyBuf,
+ b3ConstArray(b3ConvexPolyhedronData_t) cpuConvexData,
+ b3ConstArray(b3Collidable_t) cpuCollidables,
+ b3ConstArray(b3Float4) cpuVertices,
+ __global b3Float4* sepAxis,
+ const b3Float4* _dir, b3Float4* outp, int logme)
+{
+ //dir is in worldspace, move to local space
+
+ b3Float4 pos = cpuBodyBuf[bodyIndex].m_pos;
+ b3Quat orn = cpuBodyBuf[bodyIndex].m_quat;
+
+ b3Float4 dir = b3MakeFloat4((*_dir).x,(*_dir).y,(*_dir).z,0.f);
+
+ const b3Float4 localDir = b3QuatRotate(b3QuatInverse(orn),dir);
+
+
+ //find local support vertex
+ int colIndex = cpuBodyBuf[bodyIndex].m_collidableIdx;
+
+ b3Assert(cpuCollidables[colIndex].m_shapeType==SHAPE_CONVEX_HULL);
+ __global const b3ConvexPolyhedronData_t* hull = &cpuConvexData[cpuCollidables[colIndex].m_shapeIndex];
+
+ b3Float4 pInA;
+ if (logme)
+ {
+
+
+ // b3Float4 supVec = b3MakeFloat4(0,0,0,0);
+ float maxDot = -B3_LARGE_FLOAT;
+
+ if( 0 < hull->m_numVertices )
+ {
+ const b3Float4 scaled = localDir;
+ int index = b3MaxDot(scaled, &cpuVertices[hull->m_vertexOffset], hull->m_numVertices, &maxDot);
+ pInA = cpuVertices[hull->m_vertexOffset+index];
+
+ }
+
+
+ } else
+ {
+ pInA = b3LocalGetSupportVertex(localDir,hull,cpuVertices);
+ }
+
+ //move vertex to world space
+ *outp = b3TransformPoint(pInA,pos,orn);
+
+}
+
+inline void b3MprSupport(int pairIndex,int bodyIndexA, int bodyIndexB, b3ConstArray(b3RigidBodyData_t) cpuBodyBuf,
+ b3ConstArray(b3ConvexPolyhedronData_t) cpuConvexData,
+ b3ConstArray(b3Collidable_t) cpuCollidables,
+ b3ConstArray(b3Float4) cpuVertices,
+ __global b3Float4* sepAxis,
+ const b3Float4* _dir, b3MprSupport_t *supp)
+{
+ b3Float4 dir;
+ dir = *_dir;
+ b3MprConvexSupport(pairIndex,bodyIndexA,cpuBodyBuf,cpuConvexData,cpuCollidables,cpuVertices,sepAxis,&dir, &supp->v1,0);
+ dir = *_dir*-1.f;
+ b3MprConvexSupport(pairIndex,bodyIndexB,cpuBodyBuf,cpuConvexData,cpuCollidables,cpuVertices,sepAxis,&dir, &supp->v2,0);
+ supp->v = supp->v1 - supp->v2;
+}
+
+
+
+
+
+
+
+
+
+inline void b3FindOrigin(int bodyIndexA, int bodyIndexB, b3ConstArray(b3RigidBodyData_t) cpuBodyBuf, b3MprSupport_t *center)
+{
+
+ center->v1 = cpuBodyBuf[bodyIndexA].m_pos;
+ center->v2 = cpuBodyBuf[bodyIndexB].m_pos;
+ center->v = center->v1 - center->v2;
+}
+
+inline void b3MprVec3Set(b3Float4 *v, float x, float y, float z)
+{
+ (*v).x = x;
+ (*v).y = y;
+ (*v).z = z;
+ (*v).w = 0.f;
+}
+
+inline void b3MprVec3Add(b3Float4 *v, const b3Float4 *w)
+{
+ (*v).x += (*w).x;
+ (*v).y += (*w).y;
+ (*v).z += (*w).z;
+}
+
+inline void b3MprVec3Copy(b3Float4 *v, const b3Float4 *w)
+{
+ *v = *w;
+}
+
+inline void b3MprVec3Scale(b3Float4 *d, float k)
+{
+ *d *= k;
+}
+
+inline float b3MprVec3Dot(const b3Float4 *a, const b3Float4 *b)
+{
+ float dot;
+
+ dot = b3Dot3F4(*a,*b);
+ return dot;
+}
+
+
+inline float b3MprVec3Len2(const b3Float4 *v)
+{
+ return b3MprVec3Dot(v, v);
+}
+
+inline void b3MprVec3Normalize(b3Float4 *d)
+{
+ float k = 1.f / B3_MPR_SQRT(b3MprVec3Len2(d));
+ b3MprVec3Scale(d, k);
+}
+
+inline void b3MprVec3Cross(b3Float4 *d, const b3Float4 *a, const b3Float4 *b)
+{
+ *d = b3Cross3(*a,*b);
+
+}
+
+
+inline void b3MprVec3Sub2(b3Float4 *d, const b3Float4 *v, const b3Float4 *w)
+{
+ *d = *v - *w;
+}
+
+inline void b3PortalDir(const b3MprSimplex_t *portal, b3Float4 *dir)
+{
+ b3Float4 v2v1, v3v1;
+
+ b3MprVec3Sub2(&v2v1, &b3MprSimplexPoint(portal, 2)->v,
+ &b3MprSimplexPoint(portal, 1)->v);
+ b3MprVec3Sub2(&v3v1, &b3MprSimplexPoint(portal, 3)->v,
+ &b3MprSimplexPoint(portal, 1)->v);
+ b3MprVec3Cross(dir, &v2v1, &v3v1);
+ b3MprVec3Normalize(dir);
+}
+
+
+inline int portalEncapsulesOrigin(const b3MprSimplex_t *portal,
+ const b3Float4 *dir)
+{
+ float dot;
+ dot = b3MprVec3Dot(dir, &b3MprSimplexPoint(portal, 1)->v);
+ return b3MprIsZero(dot) || dot > 0.f;
+}
+
+inline int portalReachTolerance(const b3MprSimplex_t *portal,
+ const b3MprSupport_t *v4,
+ const b3Float4 *dir)
+{
+ float dv1, dv2, dv3, dv4;
+ float dot1, dot2, dot3;
+
+ // find the smallest dot product of dir and {v1-v4, v2-v4, v3-v4}
+
+ dv1 = b3MprVec3Dot(&b3MprSimplexPoint(portal, 1)->v, dir);
+ dv2 = b3MprVec3Dot(&b3MprSimplexPoint(portal, 2)->v, dir);
+ dv3 = b3MprVec3Dot(&b3MprSimplexPoint(portal, 3)->v, dir);
+ dv4 = b3MprVec3Dot(&v4->v, dir);
+
+ dot1 = dv4 - dv1;
+ dot2 = dv4 - dv2;
+ dot3 = dv4 - dv3;
+
+ dot1 = B3_MPR_FMIN(dot1, dot2);
+ dot1 = B3_MPR_FMIN(dot1, dot3);
+
+ return b3MprEq(dot1, B3_MPR_TOLERANCE) || dot1 < B3_MPR_TOLERANCE;
+}
+
+inline int portalCanEncapsuleOrigin(const b3MprSimplex_t *portal,
+ const b3MprSupport_t *v4,
+ const b3Float4 *dir)
+{
+ float dot;
+ dot = b3MprVec3Dot(&v4->v, dir);
+ return b3MprIsZero(dot) || dot > 0.f;
+}
+
+inline void b3ExpandPortal(b3MprSimplex_t *portal,
+ const b3MprSupport_t *v4)
+{
+ float dot;
+ b3Float4 v4v0;
+
+ b3MprVec3Cross(&v4v0, &v4->v, &b3MprSimplexPoint(portal, 0)->v);
+ dot = b3MprVec3Dot(&b3MprSimplexPoint(portal, 1)->v, &v4v0);
+ if (dot > 0.f){
+ dot = b3MprVec3Dot(&b3MprSimplexPoint(portal, 2)->v, &v4v0);
+ if (dot > 0.f){
+ b3MprSimplexSet(portal, 1, v4);
+ }else{
+ b3MprSimplexSet(portal, 3, v4);
+ }
+ }else{
+ dot = b3MprVec3Dot(&b3MprSimplexPoint(portal, 3)->v, &v4v0);
+ if (dot > 0.f){
+ b3MprSimplexSet(portal, 2, v4);
+ }else{
+ b3MprSimplexSet(portal, 1, v4);
+ }
+ }
+}
+
+
+
+B3_STATIC int b3DiscoverPortal(int pairIndex, int bodyIndexA, int bodyIndexB, b3ConstArray(b3RigidBodyData_t) cpuBodyBuf,
+ b3ConstArray(b3ConvexPolyhedronData_t) cpuConvexData,
+ b3ConstArray(b3Collidable_t) cpuCollidables,
+ b3ConstArray(b3Float4) cpuVertices,
+ __global b3Float4* sepAxis,
+ __global int* hasSepAxis,
+ b3MprSimplex_t *portal)
+{
+ b3Float4 dir, va, vb;
+ float dot;
+ int cont;
+
+
+
+ // vertex 0 is center of portal
+ b3FindOrigin(bodyIndexA,bodyIndexB,cpuBodyBuf, b3MprSimplexPointW(portal, 0));
+ // vertex 0 is center of portal
+ b3MprSimplexSetSize(portal, 1);
+
+
+
+ b3Float4 zero = b3MakeFloat4(0,0,0,0);
+ b3Float4* b3mpr_vec3_origin = &zero;
+
+ if (b3MprVec3Eq(&b3MprSimplexPoint(portal, 0)->v, b3mpr_vec3_origin)){
+ // Portal's center lies on origin (0,0,0) => we know that objects
+ // intersect but we would need to know penetration info.
+ // So move center little bit...
+ b3MprVec3Set(&va, FLT_EPSILON * 10.f, 0.f, 0.f);
+ b3MprVec3Add(&b3MprSimplexPointW(portal, 0)->v, &va);
+ }
+
+
+ // vertex 1 = support in direction of origin
+ b3MprVec3Copy(&dir, &b3MprSimplexPoint(portal, 0)->v);
+ b3MprVec3Scale(&dir, -1.f);
+ b3MprVec3Normalize(&dir);
+
+
+ b3MprSupport(pairIndex,bodyIndexA,bodyIndexB,cpuBodyBuf,cpuConvexData,cpuCollidables,cpuVertices, sepAxis,&dir, b3MprSimplexPointW(portal, 1));
+
+ b3MprSimplexSetSize(portal, 2);
+
+ // test if origin isn't outside of v1
+ dot = b3MprVec3Dot(&b3MprSimplexPoint(portal, 1)->v, &dir);
+
+
+ if (b3MprIsZero(dot) || dot < 0.f)
+ return -1;
+
+
+ // vertex 2
+ b3MprVec3Cross(&dir, &b3MprSimplexPoint(portal, 0)->v,
+ &b3MprSimplexPoint(portal, 1)->v);
+ if (b3MprIsZero(b3MprVec3Len2(&dir))){
+ if (b3MprVec3Eq(&b3MprSimplexPoint(portal, 1)->v, b3mpr_vec3_origin)){
+ // origin lies on v1
+ return 1;
+ }else{
+ // origin lies on v0-v1 segment
+ return 2;
+ }
+ }
+
+ b3MprVec3Normalize(&dir);
+ b3MprSupport(pairIndex,bodyIndexA,bodyIndexB,cpuBodyBuf,cpuConvexData,cpuCollidables,cpuVertices, sepAxis,&dir, b3MprSimplexPointW(portal, 2));
+
+ dot = b3MprVec3Dot(&b3MprSimplexPoint(portal, 2)->v, &dir);
+ if (b3MprIsZero(dot) || dot < 0.f)
+ return -1;
+
+ b3MprSimplexSetSize(portal, 3);
+
+ // vertex 3 direction
+ b3MprVec3Sub2(&va, &b3MprSimplexPoint(portal, 1)->v,
+ &b3MprSimplexPoint(portal, 0)->v);
+ b3MprVec3Sub2(&vb, &b3MprSimplexPoint(portal, 2)->v,
+ &b3MprSimplexPoint(portal, 0)->v);
+ b3MprVec3Cross(&dir, &va, &vb);
+ b3MprVec3Normalize(&dir);
+
+ // it is better to form portal faces to be oriented "outside" origin
+ dot = b3MprVec3Dot(&dir, &b3MprSimplexPoint(portal, 0)->v);
+ if (dot > 0.f){
+ b3MprSimplexSwap(portal, 1, 2);
+ b3MprVec3Scale(&dir, -1.f);
+ }
+
+ while (b3MprSimplexSize(portal) < 4){
+ b3MprSupport(pairIndex,bodyIndexA,bodyIndexB,cpuBodyBuf,cpuConvexData,cpuCollidables,cpuVertices, sepAxis,&dir, b3MprSimplexPointW(portal, 3));
+
+ dot = b3MprVec3Dot(&b3MprSimplexPoint(portal, 3)->v, &dir);
+ if (b3MprIsZero(dot) || dot < 0.f)
+ return -1;
+
+ cont = 0;
+
+ // test if origin is outside (v1, v0, v3) - set v2 as v3 and
+ // continue
+ b3MprVec3Cross(&va, &b3MprSimplexPoint(portal, 1)->v,
+ &b3MprSimplexPoint(portal, 3)->v);
+ dot = b3MprVec3Dot(&va, &b3MprSimplexPoint(portal, 0)->v);
+ if (dot < 0.f && !b3MprIsZero(dot)){
+ b3MprSimplexSet(portal, 2, b3MprSimplexPoint(portal, 3));
+ cont = 1;
+ }
+
+ if (!cont){
+ // test if origin is outside (v3, v0, v2) - set v1 as v3 and
+ // continue
+ b3MprVec3Cross(&va, &b3MprSimplexPoint(portal, 3)->v,
+ &b3MprSimplexPoint(portal, 2)->v);
+ dot = b3MprVec3Dot(&va, &b3MprSimplexPoint(portal, 0)->v);
+ if (dot < 0.f && !b3MprIsZero(dot)){
+ b3MprSimplexSet(portal, 1, b3MprSimplexPoint(portal, 3));
+ cont = 1;
+ }
+ }
+
+ if (cont){
+ b3MprVec3Sub2(&va, &b3MprSimplexPoint(portal, 1)->v,
+ &b3MprSimplexPoint(portal, 0)->v);
+ b3MprVec3Sub2(&vb, &b3MprSimplexPoint(portal, 2)->v,
+ &b3MprSimplexPoint(portal, 0)->v);
+ b3MprVec3Cross(&dir, &va, &vb);
+ b3MprVec3Normalize(&dir);
+ }else{
+ b3MprSimplexSetSize(portal, 4);
+ }
+ }
+
+ return 0;
+}
+
+
+B3_STATIC int b3RefinePortal(int pairIndex,int bodyIndexA, int bodyIndexB, b3ConstArray(b3RigidBodyData_t) cpuBodyBuf,
+ b3ConstArray(b3ConvexPolyhedronData_t) cpuConvexData,
+ b3ConstArray(b3Collidable_t) cpuCollidables,
+ b3ConstArray(b3Float4) cpuVertices,
+ __global b3Float4* sepAxis,
+ b3MprSimplex_t *portal)
+{
+ b3Float4 dir;
+ b3MprSupport_t v4;
+
+ for (int i=0;i<B3_MPR_MAX_ITERATIONS;i++)
+ //while (1)
+ {
+ // compute direction outside the portal (from v0 throught v1,v2,v3
+ // face)
+ b3PortalDir(portal, &dir);
+
+ // test if origin is inside the portal
+ if (portalEncapsulesOrigin(portal, &dir))
+ return 0;
+
+ // get next support point
+
+ b3MprSupport(pairIndex,bodyIndexA,bodyIndexB,cpuBodyBuf,cpuConvexData,cpuCollidables,cpuVertices, sepAxis,&dir, &v4);
+
+
+ // test if v4 can expand portal to contain origin and if portal
+ // expanding doesn't reach given tolerance
+ if (!portalCanEncapsuleOrigin(portal, &v4, &dir)
+ || portalReachTolerance(portal, &v4, &dir))
+ {
+ return -1;
+ }
+
+ // v1-v2-v3 triangle must be rearranged to face outside Minkowski
+ // difference (direction from v0).
+ b3ExpandPortal(portal, &v4);
+ }
+
+ return -1;
+}
+
+B3_STATIC void b3FindPos(const b3MprSimplex_t *portal, b3Float4 *pos)
+{
+
+ b3Float4 zero = b3MakeFloat4(0,0,0,0);
+ b3Float4* b3mpr_vec3_origin = &zero;
+
+ b3Float4 dir;
+ size_t i;
+ float b[4], sum, inv;
+ b3Float4 vec, p1, p2;
+
+ b3PortalDir(portal, &dir);
+
+ // use barycentric coordinates of tetrahedron to find origin
+ b3MprVec3Cross(&vec, &b3MprSimplexPoint(portal, 1)->v,
+ &b3MprSimplexPoint(portal, 2)->v);
+ b[0] = b3MprVec3Dot(&vec, &b3MprSimplexPoint(portal, 3)->v);
+
+ b3MprVec3Cross(&vec, &b3MprSimplexPoint(portal, 3)->v,
+ &b3MprSimplexPoint(portal, 2)->v);
+ b[1] = b3MprVec3Dot(&vec, &b3MprSimplexPoint(portal, 0)->v);
+
+ b3MprVec3Cross(&vec, &b3MprSimplexPoint(portal, 0)->v,
+ &b3MprSimplexPoint(portal, 1)->v);
+ b[2] = b3MprVec3Dot(&vec, &b3MprSimplexPoint(portal, 3)->v);
+
+ b3MprVec3Cross(&vec, &b3MprSimplexPoint(portal, 2)->v,
+ &b3MprSimplexPoint(portal, 1)->v);
+ b[3] = b3MprVec3Dot(&vec, &b3MprSimplexPoint(portal, 0)->v);
+
+ sum = b[0] + b[1] + b[2] + b[3];
+
+ if (b3MprIsZero(sum) || sum < 0.f){
+ b[0] = 0.f;
+
+ b3MprVec3Cross(&vec, &b3MprSimplexPoint(portal, 2)->v,
+ &b3MprSimplexPoint(portal, 3)->v);
+ b[1] = b3MprVec3Dot(&vec, &dir);
+ b3MprVec3Cross(&vec, &b3MprSimplexPoint(portal, 3)->v,
+ &b3MprSimplexPoint(portal, 1)->v);
+ b[2] = b3MprVec3Dot(&vec, &dir);
+ b3MprVec3Cross(&vec, &b3MprSimplexPoint(portal, 1)->v,
+ &b3MprSimplexPoint(portal, 2)->v);
+ b[3] = b3MprVec3Dot(&vec, &dir);
+
+ sum = b[1] + b[2] + b[3];
+ }
+
+ inv = 1.f / sum;
+
+ b3MprVec3Copy(&p1, b3mpr_vec3_origin);
+ b3MprVec3Copy(&p2, b3mpr_vec3_origin);
+ for (i = 0; i < 4; i++){
+ b3MprVec3Copy(&vec, &b3MprSimplexPoint(portal, i)->v1);
+ b3MprVec3Scale(&vec, b[i]);
+ b3MprVec3Add(&p1, &vec);
+
+ b3MprVec3Copy(&vec, &b3MprSimplexPoint(portal, i)->v2);
+ b3MprVec3Scale(&vec, b[i]);
+ b3MprVec3Add(&p2, &vec);
+ }
+ b3MprVec3Scale(&p1, inv);
+ b3MprVec3Scale(&p2, inv);
+
+ b3MprVec3Copy(pos, &p1);
+ b3MprVec3Add(pos, &p2);
+ b3MprVec3Scale(pos, 0.5);
+}
+
+inline float b3MprVec3Dist2(const b3Float4 *a, const b3Float4 *b)
+{
+ b3Float4 ab;
+ b3MprVec3Sub2(&ab, a, b);
+ return b3MprVec3Len2(&ab);
+}
+
+inline float _b3MprVec3PointSegmentDist2(const b3Float4 *P,
+ const b3Float4 *x0,
+ const b3Float4 *b,
+ b3Float4 *witness)
+{
+ // The computation comes from solving equation of segment:
+ // S(t) = x0 + t.d
+ // where - x0 is initial point of segment
+ // - d is direction of segment from x0 (|d| > 0)
+ // - t belongs to <0, 1> interval
+ //
+ // Than, distance from a segment to some point P can be expressed:
+ // D(t) = |x0 + t.d - P|^2
+ // which is distance from any point on segment. Minimization
+ // of this function brings distance from P to segment.
+ // Minimization of D(t) leads to simple quadratic equation that's
+ // solving is straightforward.
+ //
+ // Bonus of this method is witness point for free.
+
+ float dist, t;
+ b3Float4 d, a;
+
+ // direction of segment
+ b3MprVec3Sub2(&d, b, x0);
+
+ // precompute vector from P to x0
+ b3MprVec3Sub2(&a, x0, P);
+
+ t = -1.f * b3MprVec3Dot(&a, &d);
+ t /= b3MprVec3Len2(&d);
+
+ if (t < 0.f || b3MprIsZero(t)){
+ dist = b3MprVec3Dist2(x0, P);
+ if (witness)
+ b3MprVec3Copy(witness, x0);
+ }else if (t > 1.f || b3MprEq(t, 1.f)){
+ dist = b3MprVec3Dist2(b, P);
+ if (witness)
+ b3MprVec3Copy(witness, b);
+ }else{
+ if (witness){
+ b3MprVec3Copy(witness, &d);
+ b3MprVec3Scale(witness, t);
+ b3MprVec3Add(witness, x0);
+ dist = b3MprVec3Dist2(witness, P);
+ }else{
+ // recycling variables
+ b3MprVec3Scale(&d, t);
+ b3MprVec3Add(&d, &a);
+ dist = b3MprVec3Len2(&d);
+ }
+ }
+
+ return dist;
+}
+
+
+inline float b3MprVec3PointTriDist2(const b3Float4 *P,
+ const b3Float4 *x0, const b3Float4 *B,
+ const b3Float4 *C,
+ b3Float4 *witness)
+{
+ // Computation comes from analytic expression for triangle (x0, B, C)
+ // T(s, t) = x0 + s.d1 + t.d2, where d1 = B - x0 and d2 = C - x0 and
+ // Then equation for distance is:
+ // D(s, t) = | T(s, t) - P |^2
+ // This leads to minimization of quadratic function of two variables.
+ // The solution from is taken only if s is between 0 and 1, t is
+ // between 0 and 1 and t + s < 1, otherwise distance from segment is
+ // computed.
+
+ b3Float4 d1, d2, a;
+ float u, v, w, p, q, r;
+ float s, t, dist, dist2;
+ b3Float4 witness2;
+
+ b3MprVec3Sub2(&d1, B, x0);
+ b3MprVec3Sub2(&d2, C, x0);
+ b3MprVec3Sub2(&a, x0, P);
+
+ u = b3MprVec3Dot(&a, &a);
+ v = b3MprVec3Dot(&d1, &d1);
+ w = b3MprVec3Dot(&d2, &d2);
+ p = b3MprVec3Dot(&a, &d1);
+ q = b3MprVec3Dot(&a, &d2);
+ r = b3MprVec3Dot(&d1, &d2);
+
+ s = (q * r - w * p) / (w * v - r * r);
+ t = (-s * r - q) / w;
+
+ if ((b3MprIsZero(s) || s > 0.f)
+ && (b3MprEq(s, 1.f) || s < 1.f)
+ && (b3MprIsZero(t) || t > 0.f)
+ && (b3MprEq(t, 1.f) || t < 1.f)
+ && (b3MprEq(t + s, 1.f) || t + s < 1.f)){
+
+ if (witness){
+ b3MprVec3Scale(&d1, s);
+ b3MprVec3Scale(&d2, t);
+ b3MprVec3Copy(witness, x0);
+ b3MprVec3Add(witness, &d1);
+ b3MprVec3Add(witness, &d2);
+
+ dist = b3MprVec3Dist2(witness, P);
+ }else{
+ dist = s * s * v;
+ dist += t * t * w;
+ dist += 2.f * s * t * r;
+ dist += 2.f * s * p;
+ dist += 2.f * t * q;
+ dist += u;
+ }
+ }else{
+ dist = _b3MprVec3PointSegmentDist2(P, x0, B, witness);
+
+ dist2 = _b3MprVec3PointSegmentDist2(P, x0, C, &witness2);
+ if (dist2 < dist){
+ dist = dist2;
+ if (witness)
+ b3MprVec3Copy(witness, &witness2);
+ }
+
+ dist2 = _b3MprVec3PointSegmentDist2(P, B, C, &witness2);
+ if (dist2 < dist){
+ dist = dist2;
+ if (witness)
+ b3MprVec3Copy(witness, &witness2);
+ }
+ }
+
+ return dist;
+}
+
+
+B3_STATIC void b3FindPenetr(int pairIndex,int bodyIndexA, int bodyIndexB, b3ConstArray(b3RigidBodyData_t) cpuBodyBuf,
+ b3ConstArray(b3ConvexPolyhedronData_t) cpuConvexData,
+ b3ConstArray(b3Collidable_t) cpuCollidables,
+ b3ConstArray(b3Float4) cpuVertices,
+ __global b3Float4* sepAxis,
+ b3MprSimplex_t *portal,
+ float *depth, b3Float4 *pdir, b3Float4 *pos)
+{
+ b3Float4 dir;
+ b3MprSupport_t v4;
+ unsigned long iterations;
+
+ b3Float4 zero = b3MakeFloat4(0,0,0,0);
+ b3Float4* b3mpr_vec3_origin = &zero;
+
+
+ iterations = 1UL;
+ for (int i=0;i<B3_MPR_MAX_ITERATIONS;i++)
+ //while (1)
+ {
+ // compute portal direction and obtain next support point
+ b3PortalDir(portal, &dir);
+
+ b3MprSupport(pairIndex,bodyIndexA,bodyIndexB,cpuBodyBuf,cpuConvexData,cpuCollidables,cpuVertices, sepAxis,&dir, &v4);
+
+
+ // reached tolerance -> find penetration info
+ if (portalReachTolerance(portal, &v4, &dir)
+ || iterations ==B3_MPR_MAX_ITERATIONS)
+ {
+ *depth = b3MprVec3PointTriDist2(b3mpr_vec3_origin,&b3MprSimplexPoint(portal, 1)->v,&b3MprSimplexPoint(portal, 2)->v,&b3MprSimplexPoint(portal, 3)->v,pdir);
+ *depth = B3_MPR_SQRT(*depth);
+
+ if (b3MprIsZero((*pdir).x) && b3MprIsZero((*pdir).y) && b3MprIsZero((*pdir).z))
+ {
+
+ *pdir = dir;
+ }
+ b3MprVec3Normalize(pdir);
+
+ // barycentric coordinates:
+ b3FindPos(portal, pos);
+
+
+ return;
+ }
+
+ b3ExpandPortal(portal, &v4);
+
+ iterations++;
+ }
+}
+
+B3_STATIC void b3FindPenetrTouch(b3MprSimplex_t *portal,float *depth, b3Float4 *dir, b3Float4 *pos)
+{
+ // Touching contact on portal's v1 - so depth is zero and direction
+ // is unimportant and pos can be guessed
+ *depth = 0.f;
+ b3Float4 zero = b3MakeFloat4(0,0,0,0);
+ b3Float4* b3mpr_vec3_origin = &zero;
+
+
+ b3MprVec3Copy(dir, b3mpr_vec3_origin);
+
+ b3MprVec3Copy(pos, &b3MprSimplexPoint(portal, 1)->v1);
+ b3MprVec3Add(pos, &b3MprSimplexPoint(portal, 1)->v2);
+ b3MprVec3Scale(pos, 0.5);
+}
+
+B3_STATIC void b3FindPenetrSegment(b3MprSimplex_t *portal,
+ float *depth, b3Float4 *dir, b3Float4 *pos)
+{
+
+ // Origin lies on v0-v1 segment.
+ // Depth is distance to v1, direction also and position must be
+ // computed
+
+ b3MprVec3Copy(pos, &b3MprSimplexPoint(portal, 1)->v1);
+ b3MprVec3Add(pos, &b3MprSimplexPoint(portal, 1)->v2);
+ b3MprVec3Scale(pos, 0.5f);
+
+
+ b3MprVec3Copy(dir, &b3MprSimplexPoint(portal, 1)->v);
+ *depth = B3_MPR_SQRT(b3MprVec3Len2(dir));
+ b3MprVec3Normalize(dir);
+}
+
+
+
+inline int b3MprPenetration(int pairIndex, int bodyIndexA, int bodyIndexB,
+ b3ConstArray(b3RigidBodyData_t) cpuBodyBuf,
+ b3ConstArray(b3ConvexPolyhedronData_t) cpuConvexData,
+ b3ConstArray(b3Collidable_t) cpuCollidables,
+ b3ConstArray(b3Float4) cpuVertices,
+ __global b3Float4* sepAxis,
+ __global int* hasSepAxis,
+ float *depthOut, b3Float4* dirOut, b3Float4* posOut)
+{
+
+ b3MprSimplex_t portal;
+
+
+// if (!hasSepAxis[pairIndex])
+ // return -1;
+
+ hasSepAxis[pairIndex] = 0;
+ int res;
+
+ // Phase 1: Portal discovery
+ res = b3DiscoverPortal(pairIndex,bodyIndexA,bodyIndexB,cpuBodyBuf,cpuConvexData,cpuCollidables,cpuVertices,sepAxis,hasSepAxis, &portal);
+
+
+ //sepAxis[pairIndex] = *pdir;//or -dir?
+
+ switch (res)
+ {
+ case 0:
+ {
+ // Phase 2: Portal refinement
+
+ res = b3RefinePortal(pairIndex,bodyIndexA,bodyIndexB,cpuBodyBuf,cpuConvexData,cpuCollidables,cpuVertices, sepAxis,&portal);
+ if (res < 0)
+ return -1;
+
+ // Phase 3. Penetration info
+ b3FindPenetr(pairIndex,bodyIndexA,bodyIndexB,cpuBodyBuf,cpuConvexData,cpuCollidables,cpuVertices, sepAxis,&portal, depthOut, dirOut, posOut);
+ hasSepAxis[pairIndex] = 1;
+ sepAxis[pairIndex] = -*dirOut;
+ break;
+ }
+ case 1:
+ {
+ // Touching contact on portal's v1.
+ b3FindPenetrTouch(&portal, depthOut, dirOut, posOut);
+ break;
+ }
+ case 2:
+ {
+
+ b3FindPenetrSegment( &portal, depthOut, dirOut, posOut);
+ break;
+ }
+ default:
+ {
+ hasSepAxis[pairIndex]=0;
+ //if (res < 0)
+ //{
+ // Origin isn't inside portal - no collision.
+ return -1;
+ //}
+ }
+ };
+
+ return 0;
+};
+
+
+
+#endif //B3_MPR_PENETRATION_H