diff -r 000000000000 -r 2f259fa3e83a ode/src/box.cpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/ode/src/box.cpp Tue Feb 02 01:00:49 2010 +0200 @@ -0,0 +1,813 @@ +/************************************************************************* + * * + * Open Dynamics Engine, Copyright (C) 2001-2003 Russell L. Smith. * + * All rights reserved. Email: russ@q12.org Web: www.q12.org * + * * + * This library is free software; you can redistribute it and/or * + * modify it under the terms of EITHER: * + * (1) The GNU Lesser General Public License as published by the Free * + * Software Foundation; either version 2.1 of the License, or (at * + * your option) any later version. The text of the GNU Lesser * + * General Public License is included with this library in the * + * file LICENSE.TXT. * + * (2) The BSD-style license that is included with this library in * + * the file LICENSE-BSD.TXT. * + * * + * This library is distributed in the hope that it will be useful, * + * but WITHOUT ANY WARRANTY; without even the implied warranty of * + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the files * + * LICENSE.TXT and LICENSE-BSD.TXT for more details. * + * * + *************************************************************************/ + +/* + +standard ODE geometry primitives: public API and pairwise collision functions. + +the rule is that only the low level primitive collision functions should set +dContactGeom::g1 and dContactGeom::g2. + +*/ + +#include +#include +#include +#include +#include +#include "collision_kernel.h" +#include "collision_std.h" +#include "collision_util.h" + + +//**************************************************************************** +// box public API + +dxBox::dxBox (dSpaceID space, dReal lx, dReal ly, dReal lz) : dxGeom (space,1) +{ + type = dBoxClass; + side[0] = lx; + side[1] = ly; + side[2] = lz; +} + + +void dxBox::computeAABB() +{ + const dMatrix3& R = final_posr->R; + const dVector3& pos = final_posr->pos; + + dReal xrange = dMUL(REAL(0.5),(dFabs (dMUL(R[0],side[0])) + + dFabs (dMUL(R[1],side[1])) + dFabs (dMUL(R[2],side[2])))); + dReal yrange = dMUL(REAL(0.5),(dFabs (dMUL(R[4],side[0])) + + dFabs (dMUL(R[5],side[1])) + dFabs (dMUL(R[6],side[2])))); + dReal zrange = dMUL(REAL(0.5),(dFabs (dMUL(R[8],side[0])) + + dFabs (dMUL(R[9],side[1])) + dFabs (dMUL(R[10],side[2])))); + aabb[0] = pos[0] - xrange; + aabb[1] = pos[0] + xrange; + aabb[2] = pos[1] - yrange; + aabb[3] = pos[1] + yrange; + aabb[4] = pos[2] - zrange; + aabb[5] = pos[2] + zrange; +} + + +EXPORT_C dGeomID dCreateBox (dSpaceID space, dReal lx, dReal ly, dReal lz) +{ + return new dxBox (space,lx,ly,lz); +} + + +EXPORT_C void dGeomBoxSetLengths (dGeomID g, dReal lx, dReal ly, dReal lz) +{ + dxBox *b = (dxBox*) g; + b->side[0] = lx; + b->side[1] = ly; + b->side[2] = lz; + dGeomMoved (g); +} + + +EXPORT_C void dGeomBoxGetLengths (dGeomID g, dVector3 result) +{ + dxBox *b = (dxBox*) g; + result[0] = b->side[0]; + result[1] = b->side[1]; + result[2] = b->side[2]; +} + + +EXPORT_C dReal dGeomBoxPointDepth (dGeomID g, dReal x, dReal y, dReal z) +{ + g->recomputePosr(); + dxBox *b = (dxBox*) g; + + // Set p = (x,y,z) relative to box center + // + // This will be (0,0,0) if the point is at (side[0]/2,side[1]/2,side[2]/2) + + dVector3 p,q; + + p[0] = x - b->final_posr->pos[0]; + p[1] = y - b->final_posr->pos[1]; + p[2] = z - b->final_posr->pos[2]; + + // Rotate p into box's coordinate frame, so we can + // treat the OBB as an AABB + + dMULTIPLY1_331 (q,b->final_posr->R,p); + + // Record distance from point to each successive box side, and see + // if the point is inside all six sides + + dReal dist[6]; + int i; + + bool inside = true; + + for (i=0; i < 3; i++) { + dReal side = dMUL(b->side[i],REAL(0.5)); + + dist[i ] = side - q[i]; + dist[i+3] = side + q[i]; + + if ((dist[i] < 0) || (dist[i+3] < 0)) { + inside = false; + } + } + + // If point is inside the box, the depth is the smallest positive distance + // to any side + + if (inside) { + dReal smallest_dist = (dReal) (unsigned) -1; + + for (i=0; i < 6; i++) { + if (dist[i] < smallest_dist) smallest_dist = dist[i]; + } + + return smallest_dist; + } + + // Otherwise, if point is outside the box, the depth is the largest + // distance to any side. This is an approximation to the 'proper' + // solution (the proper solution may be larger in some cases). + + dReal largest_dist = 0; + + for (i=0; i < 6; i++) { + if (dist[i] > largest_dist) largest_dist = dist[i]; + } + + return -largest_dist; +} + +//**************************************************************************** +// box-box collision utility + + +// find all the intersection points between the 2D rectangle with vertices +// at (+/-h[0],+/-h[1]) and the 2D quadrilateral with vertices (p[0],p[1]), +// (p[2],p[3]),(p[4],p[5]),(p[6],p[7]). +// +// the intersection points are returned as x,y pairs in the 'ret' array. +// the number of intersection points is returned by the function (this will +// be in the range 0 to 8). + +static int intersectRectQuad (dReal h[2], dReal p[8], dReal ret[16]) +{ + // q (and r) contain nq (and nr) coordinate points for the current (and + // chopped) polygons + int nq=4,nr; + dReal buffer[16]; + dReal *q = p; + dReal *r = ret; + for (int dir=0; dir <= 1; dir++) { + // direction notation: xy[0] = x axis, xy[1] = y axis + for (int sign=-1; sign <= 1; sign += 2) { + // chop q along the line xy[dir] = sign*h[dir] + dReal *pq = q; + dReal *pr = r; + nr = 0; + for (int i=nq; i > 0; i--) { + // go through all points in q and all lines between adjacent points + if (sign*pq[dir] < h[dir]) { + // this point is inside the chopping line + pr[0] = pq[0]; + pr[1] = pq[1]; + pr += 2; + nr++; + if (nr & 8) { + q = r; + goto done; + } + } + dReal *nextq = (i > 1) ? pq+2 : q; + if ((sign*pq[dir] < h[dir]) ^ (sign*nextq[dir] < h[dir])) { + // this line crosses the chopping line + pr[1-dir] = pq[1-dir] + dMUL(dDIV((nextq[1-dir]-pq[1-dir]),(nextq[dir]-pq[dir])),(sign*h[dir]-pq[dir])); + pr[dir] = sign*h[dir]; + pr += 2; + nr++; + if (nr & 8) { + q = r; + goto done; + } + } + pq += 2; + } + q = r; + r = (q==ret) ? buffer : ret; + nq = nr; + } + } + done: + if (q != ret) memcpy (ret,q,nr*2*sizeof(dReal)); + return nr; +} + + +// given n points in the plane (array p, of size 2*n), generate m points that +// best represent the whole set. the definition of 'best' here is not +// predetermined - the idea is to select points that give good box-box +// collision detection behavior. the chosen point indexes are returned in the +// array iret (of size m). 'i0' is always the first entry in the array. +// n must be in the range [1..8]. m must be in the range [1..n]. i0 must be +// in the range [0..n-1]. + +void cullPoints (int n, dReal p[], int m, int i0, int iret[]) +{ + // compute the centroid of the polygon in cx,cy + int i,j; + dReal a,cx,cy,q; + if (n==1) { + cx = p[0]; + cy = p[1]; + } + else if (n==2) { + cx = dMUL(REAL(0.5),(p[0] + p[2])); + cy = dMUL(REAL(0.5),(p[1] + p[3])); + } + else { + a = 0; + cx = 0; + cy = 0; + for (i=0; i<(n-1); i++) { + q = dMUL(p[i*2],p[i*2+3]) - dMUL(p[i*2+2],p[i*2+1]); + a += q; + cx += dMUL(q,(p[i*2]+p[i*2+2])); + cy += dMUL(q,(p[i*2+1]+p[i*2+3])); + } + q = dMUL(p[n*2-2],p[1]) - dMUL(p[0],p[n*2-1]); + a = dRecip(dMUL(REAL(3.0),(a+q))); + cx = dMUL(a,(cx + dMUL(q,(p[n*2-2]+p[0])))); + cy = dMUL(a,(cy + dMUL(q,(p[n*2-1]+p[1])))); + } + + // compute the angle of each point w.r.t. the centroid + dReal A[8]; + for (i=0; i dPI) a -= 2*dPI; + dReal maxdiff = REAL(1e9); + dReal diff; +#ifndef dNODEBUG + *iret = i0; // iret is not allowed to keep this value +#endif + for (i=0; i dPI) diff = 2*dPI - diff; + if (diff < maxdiff) { + maxdiff = diff; + *iret = i; + } + } + } + avail[*iret] = 0; + iret++; + } +} + + +// given two boxes (p1,R1,side1) and (p2,R2,side2), collide them together and +// generate contact points. this returns 0 if there is no contact otherwise +// it returns the number of contacts generated. +// `normal' returns the contact normal. +// `depth' returns the maximum penetration depth along that normal. +// `return_code' returns a number indicating the type of contact that was +// detected: +// 1,2,3 = box 2 intersects with a face of box 1 +// 4,5,6 = box 1 intersects with a face of box 2 +// 7..15 = edge-edge contact +// `maxc' is the maximum number of contacts allowed to be generated, i.e. +// the size of the `contact' array. +// `contact' and `skip' are the contact array information provided to the +// collision functions. this function only fills in the position and depth +// fields. + +EXPORT_C int dBoxBox (const dVector3 p1, const dMatrix3 R1, + const dVector3 side1, const dVector3 p2, + const dMatrix3 R2, const dVector3 side2, + dVector3 normal, dReal *depth, int *return_code, + int maxc, dContactGeom *contact, int skip) +{ + const dReal fudge_factor = REAL(1.05); + dVector3 p,pp,normalC; + const dReal *normalR = 0; + dReal A[3],B[3],R11,R12,R13,R21,R22,R23,R31,R32,R33, + Q11,Q12,Q13,Q21,Q22,Q23,Q31,Q32,Q33,s,s2,l; + int i,j,invert_normal,code; + + // get vector from centers of box 1 to box 2, relative to box 1 + p[0] = p2[0] - p1[0]; + p[1] = p2[1] - p1[1]; + p[2] = p2[2] - p1[2]; + dMULTIPLY1_331 (pp,R1,p); // get pp = p relative to body 1 + + // get side lengths / 2 + A[0] = dMUL(side1[0],REAL(0.5)); + A[1] = dMUL(side1[1],REAL(0.5)); + A[2] = dMUL(side1[2],REAL(0.5)); + B[0] = dMUL(side2[0],REAL(0.5)); + B[1] = dMUL(side2[1],REAL(0.5)); + B[2] = dMUL(side2[2],REAL(0.5)); + + // Rij is R1'*R2, i.e. the relative rotation between R1 and R2 + R11 = dDOT44(R1+0,R2+0); R12 = dDOT44(R1+0,R2+1); R13 = dDOT44(R1+0,R2+2); + R21 = dDOT44(R1+1,R2+0); R22 = dDOT44(R1+1,R2+1); R23 = dDOT44(R1+1,R2+2); + R31 = dDOT44(R1+2,R2+0); R32 = dDOT44(R1+2,R2+1); R33 = dDOT44(R1+2,R2+2); + + Q11 = dFabs(R11); Q12 = dFabs(R12); Q13 = dFabs(R13); + Q21 = dFabs(R21); Q22 = dFabs(R22); Q23 = dFabs(R23); + Q31 = dFabs(R31); Q32 = dFabs(R32); Q33 = dFabs(R33); + + // for all 15 possible separating axes: + // * see if the axis separates the boxes. if so, return 0. + // * find the depth of the penetration along the separating axis (s2) + // * if this is the largest depth so far, record it. + // the normal vector will be set to the separating axis with the smallest + // depth. note: normalR is set to point to a column of R1 or R2 if that is + // the smallest depth normal so far. otherwise normalR is 0 and normalC is + // set to a vector relative to body 1. invert_normal is 1 if the sign of + // the normal should be flipped. + +#define TST(expr1,expr2,norm,cc) \ + s2 = dFabs(expr1) - (expr2); \ + if (s2 > 0) return 0; \ + if (s2 > s) { \ + s = s2; \ + normalR = norm; \ + invert_normal = ((expr1) < 0); \ + code = (cc); \ + } + + s = -dInfinity; + invert_normal = 0; + code = 0; + + // separating axis = u1,u2,u3 + TST (pp[0],(A[0] + dMUL(B[0],Q11) + dMUL(B[1],Q12) + dMUL(B[2],Q13)),R1+0,1); + TST (pp[1],(A[1] + dMUL(B[0],Q21) + dMUL(B[1],Q22) + dMUL(B[2],Q23)),R1+1,2); + TST (pp[2],(A[2] + dMUL(B[0],Q31) + dMUL(B[1],Q32) + dMUL(B[2],Q33)),R1+2,3); + + // separating axis = v1,v2,v3 + TST (dDOT41(R2+0,p),(dMUL(A[0],Q11) + dMUL(A[1],Q21) + dMUL(A[2],Q31) + B[0]),R2+0,4); + TST (dDOT41(R2+1,p),(dMUL(A[0],Q12) + dMUL(A[1],Q22) + dMUL(A[2],Q32) + B[1]),R2+1,5); + TST (dDOT41(R2+2,p),(dMUL(A[0],Q13) + dMUL(A[1],Q23) + dMUL(A[2],Q33) + B[2]),R2+2,6); + + // note: cross product axes need to be scaled when s is computed. + // normal (n1,n2,n3) is relative to box 1. +#undef TST +#define TST(expr1,expr2,n1,n2,n3,cc) \ + s2 = dFabs(expr1) - (expr2); \ + if (s2 > 0) return 0; \ + l = dSqrt (dMUL((n1),(n1)) + dMUL((n2),(n2)) + dMUL((n3),(n3))); \ + if (l > 0) { \ + s2 = dDIV(s2,l); \ + if (dMUL(s2,fudge_factor) > s) { \ + s = s2; \ + normalR = 0; \ + normalC[0] = dDIV((n1),l); normalC[1] = dDIV((n2),l); normalC[2] = dDIV((n3),l); \ + invert_normal = ((expr1) < 0); \ + code = (cc); \ + } \ + } + + // separating axis = u1 x (v1,v2,v3) + TST((dMUL(pp[2],R21)-dMUL(pp[1],R31)),(dMUL(A[1],Q31)+dMUL(A[2],Q21)+dMUL(B[1],Q13)+dMUL(B[2],Q12)),0,-R31,R21,7); + TST((dMUL(pp[2],R22)-dMUL(pp[1],R32)),(dMUL(A[1],Q32)+dMUL(A[2],Q22)+dMUL(B[0],Q13)+dMUL(B[2],Q11)),0,-R32,R22,8); + TST((dMUL(pp[2],R23)-dMUL(pp[1],R33)),(dMUL(A[1],Q33)+dMUL(A[2],Q23)+dMUL(B[0],Q12)+dMUL(B[1],Q11)),0,-R33,R23,9); + + // separating axis = u2 x (v1,v2,v3) + TST((dMUL(pp[0],R31)-dMUL(pp[2],R11)),(dMUL(A[0],Q31)+dMUL(A[2],Q11)+dMUL(B[1],Q23)+dMUL(B[2],Q22)),R31,0,-R11,10); + TST((dMUL(pp[0],R32)-dMUL(pp[2],R12)),(dMUL(A[0],Q32)+dMUL(A[2],Q12)+dMUL(B[0],Q23)+dMUL(B[2],Q21)),R32,0,-R12,11); + TST((dMUL(pp[0],R33)-dMUL(pp[2],R13)),(dMUL(A[0],Q33)+dMUL(A[2],Q13)+dMUL(B[0],Q22)+dMUL(B[1],Q21)),R33,0,-R13,12); + + // separating axis = u3 x (v1,v2,v3) + TST((dMUL(pp[1],R11)-dMUL(pp[0],R21)),(dMUL(A[0],Q21)+dMUL(A[1],Q11)+dMUL(B[1],Q33)+dMUL(B[2],Q32)),-R21,R11,0,13); + TST((dMUL(pp[1],R12)-dMUL(pp[0],R22)),(dMUL(A[0],Q22)+dMUL(A[1],Q12)+dMUL(B[0],Q33)+dMUL(B[2],Q31)),-R22,R12,0,14); + TST((dMUL(pp[1],R13)-dMUL(pp[0],R23)),(dMUL(A[0],Q23)+dMUL(A[1],Q13)+dMUL(B[0],Q32)+dMUL(B[1],Q31)),-R23,R13,0,15); + +#undef TST + + if (!code) return 0; + + // if we get to this point, the boxes interpenetrate. compute the normal + // in global coordinates. + if (normalR) { + normal[0] = normalR[0]; + normal[1] = normalR[4]; + normal[2] = normalR[8]; + } + else { + dMULTIPLY0_331 (normal,R1,normalC); + } + if (invert_normal) { + normal[0] = -normal[0]; + normal[1] = -normal[1]; + normal[2] = -normal[2]; + } + *depth = -s; + + // compute contact point(s) + + if (code > 6) { + // an edge from box 1 touches an edge from box 2. + // find a point pa on the intersecting edge of box 1 + dVector3 pa; + dReal sign; + for (i=0; i<3; i++) pa[i] = p1[i]; + for (j=0; j<3; j++) { + sign = (dDOT14(normal,R1+j) > 0) ? REAL(1.0) : REAL(-1.0); + for (i=0; i<3; i++) pa[i] += dMUL(sign,dMUL(A[j],R1[i*4+j])); + } + + // find a point pb on the intersecting edge of box 2 + dVector3 pb; + for (i=0; i<3; i++) pb[i] = p2[i]; + for (j=0; j<3; j++) { + sign = (dDOT14(normal,R2+j) > 0) ? REAL(-1.0) : REAL(1.0); + for (i=0; i<3; i++) pb[i] += dMUL(sign,dMUL(B[j],R2[i*4+j])); + } + + dReal alpha,beta; + dVector3 ua,ub; + for (i=0; i<3; i++) ua[i] = R1[((code)-7)/3 + i*4]; + for (i=0; i<3; i++) ub[i] = R2[((code)-7)%3 + i*4]; + + dLineClosestApproach (pa,ua,pb,ub,&alpha,&beta); + for (i=0; i<3; i++) pa[i] += dMUL(ua[i],alpha); + for (i=0; i<3; i++) pb[i] += dMUL(ub[i],beta); + + for (i=0; i<3; i++) contact[0].pos[i] = dMUL(REAL(0.5),(pa[i]+pb[i])); + contact[0].depth = *depth; + *return_code = code; + return 1; + } + + // okay, we have a face-something intersection (because the separating + // axis is perpendicular to a face). define face 'a' to be the reference + // face (i.e. the normal vector is perpendicular to this) and face 'b' to be + // the incident face (the closest face of the other box). + + const dReal *Ra,*Rb,*pa,*pb,*Sa,*Sb; + if (code <= 3) { + Ra = R1; + Rb = R2; + pa = p1; + pb = p2; + Sa = A; + Sb = B; + } + else { + Ra = R2; + Rb = R1; + pa = p2; + pb = p1; + Sa = B; + Sb = A; + } + + // nr = normal vector of reference face dotted with axes of incident box. + // anr = absolute values of nr. + dVector3 normal2,nr,anr; + if (code <= 3) { + normal2[0] = normal[0]; + normal2[1] = normal[1]; + normal2[2] = normal[2]; + } + else { + normal2[0] = -normal[0]; + normal2[1] = -normal[1]; + normal2[2] = -normal[2]; + } + dMULTIPLY1_331 (nr,Rb,normal2); + anr[0] = dFabs (nr[0]); + anr[1] = dFabs (nr[1]); + anr[2] = dFabs (nr[2]); + + // find the largest compontent of anr: this corresponds to the normal + // for the indident face. the other axis numbers of the indicent face + // are stored in a1,a2. + int lanr,a1,a2; + if (anr[1] > anr[0]) { + if (anr[1] > anr[2]) { + a1 = 0; + lanr = 1; + a2 = 2; + } + else { + a1 = 0; + a2 = 1; + lanr = 2; + } + } + else { + if (anr[0] > anr[2]) { + lanr = 0; + a1 = 1; + a2 = 2; + } + else { + a1 = 0; + a2 = 1; + lanr = 2; + } + } + + // compute center point of incident face, in reference-face coordinates + dVector3 center; + if (nr[lanr] < 0) { + for (i=0; i<3; i++) center[i] = pb[i] - pa[i] + dMUL(Sb[lanr],Rb[i*4+lanr]); + } + else { + for (i=0; i<3; i++) center[i] = pb[i] - pa[i] - dMUL(Sb[lanr],Rb[i*4+lanr]); + } + + // find the normal and non-normal axis numbers of the reference box + int codeN,code1,code2; + if (code <= 3) codeN = code-1; else codeN = code-4; + if (codeN==0) { + code1 = 1; + code2 = 2; + } + else if (codeN==1) { + code1 = 0; + code2 = 2; + } + else { + code1 = 0; + code2 = 1; + } + + // find the four corners of the incident face, in reference-face coordinates + dReal quad[8]; // 2D coordinate of incident face (x,y pairs) + dReal c1,c2,m11,m12,m21,m22; + c1 = dDOT14 (center,Ra+code1); + c2 = dDOT14 (center,Ra+code2); + // optimize this? - we have already computed this data above, but it is not + // stored in an easy-to-index format. for now it's quicker just to recompute + // the four dot products. + m11 = dDOT44 (Ra+code1,Rb+a1); + m12 = dDOT44 (Ra+code1,Rb+a2); + m21 = dDOT44 (Ra+code2,Rb+a1); + m22 = dDOT44 (Ra+code2,Rb+a2); + { + dReal k1 = dMUL(m11,Sb[a1]); + dReal k2 = dMUL(m21,Sb[a1]); + dReal k3 = dMUL(m12,Sb[a2]); + dReal k4 = dMUL(m22,Sb[a2]); + quad[0] = c1 - k1 - k3; + quad[1] = c2 - k2 - k4; + quad[2] = c1 - k1 + k3; + quad[3] = c2 - k2 + k4; + quad[4] = c1 + k1 + k3; + quad[5] = c2 + k2 + k4; + quad[6] = c1 + k1 - k3; + quad[7] = c2 + k2 - k4; + } + + // find the size of the reference face + dReal rect[2]; + rect[0] = Sa[code1]; + rect[1] = Sa[code2]; + + // intersect the incident and reference faces + dReal ret[16]; + int n = intersectRectQuad (rect,quad,ret); + if (n < 1) return 0; // this should never happen + + // convert the intersection points into reference-face coordinates, + // and compute the contact position and depth for each point. only keep + // those points that have a positive (penetrating) depth. delete points in + // the 'ret' array as necessary so that 'point' and 'ret' correspond. + dReal point[3*8]; // penetrating contact points + dReal dep[8]; // depths for those points + dReal det1 = dRecip(dMUL(m11,m22) - dMUL(m12,m21)); + m11 = dMUL(m11,det1); + m12 = dMUL(m12,det1); + m21 = dMUL(m21,det1); + m22 = dMUL(m22,det1); + int cnum = 0; // number of penetrating contact points found + for (j=0; j < n; j++) { + dReal k1 = dMUL(m22,(ret[j*2]-c1)) - dMUL(m12,(ret[j*2+1]-c2)); + dReal k2 = -dMUL(m21,(ret[j*2]-c1)) + dMUL(m11,(ret[j*2+1]-c2)); + for (i=0; i<3; i++) point[cnum*3+i] = + center[i] + dMUL(k1,Rb[i*4+a1]) + dMUL(k2,Rb[i*4+a2]); + dep[cnum] = Sa[codeN] - dDOT(normal2,point+cnum*3); + if (dep[cnum] >= 0) { + ret[cnum*2] = ret[j*2]; + ret[cnum*2+1] = ret[j*2+1]; + cnum++; + } + } + if (cnum < 1) return 0; // this should never happen + + // we can't generate more contacts than we actually have + if (maxc > cnum) maxc = cnum; + if (maxc < 1) maxc = 1; + + if (cnum <= maxc) { + // we have less contacts than we need, so we use them all + for (j=0; j < cnum; j++) { + dContactGeom *con = CONTACT(contact,skip*j); + for (i=0; i<3; i++) con->pos[i] = point[j*3+i] + pa[i]; + con->depth = dep[j]; + } + } + else { + // we have more contacts than are wanted, some of them must be culled. + // find the deepest point, it is always the first contact. + int i1 = 0; + dReal maxdepth = dep[0]; + for (i=1; i maxdepth) { + maxdepth = dep[i]; + i1 = i; + } + } + + int iret[8]; + cullPoints (cnum,ret,maxc,i1,iret); + + for (j=0; j < maxc; j++) { + dContactGeom *con = CONTACT(contact,skip*j); + for (i=0; i<3; i++) con->pos[i] = point[iret[j]*3+i] + pa[i]; + con->depth = dep[iret[j]]; + } + cnum = maxc; + } + + *return_code = code; + return cnum; +} + + + +int dCollideBoxBox (dxGeom *o1, dxGeom *o2, int flags, + dContactGeom *contact, int skip) +{ + dVector3 normal; + dReal depth; + int code; + dxBox *b1 = (dxBox*) o1; + dxBox *b2 = (dxBox*) o2; + int num = dBoxBox (o1->final_posr->pos,o1->final_posr->R,b1->side, o2->final_posr->pos,o2->final_posr->R,b2->side, + normal,&depth,&code,flags & NUMC_MASK,contact,skip); + for (int i=0; inormal[0] = -normal[0]; + CONTACT(contact,i*skip)->normal[1] = -normal[1]; + CONTACT(contact,i*skip)->normal[2] = -normal[2]; + CONTACT(contact,i*skip)->g1 = o1; + CONTACT(contact,i*skip)->g2 = o2; + } + return num; +} + + +int dCollideBoxPlane (dxGeom *o1, dxGeom *o2, + int flags, dContactGeom *contact, int skip) +{ + dxBox *box = (dxBox*) o1; + dxPlane *plane = (dxPlane*) o2; + + contact->g1 = o1; + contact->g2 = o2; + int ret = 0; + + //@@@ problem: using 4-vector (plane->p) as 3-vector (normal). + const dReal *R = o1->final_posr->R; // rotation of box + const dReal *n = plane->p; // normal vector + + // project sides lengths along normal vector, get absolute values + dReal Q1 = dDOT14(n,R+0); + dReal Q2 = dDOT14(n,R+1); + dReal Q3 = dDOT14(n,R+2); + dReal A1 = dMUL(box->side[0],Q1); + dReal A2 = dMUL(box->side[1],Q2); + dReal A3 = dMUL(box->side[2],Q3); + dReal B1 = dFabs(A1); + dReal B2 = dFabs(A2); + dReal B3 = dFabs(A3); + + // early exit test + dReal depth = plane->p[3] + dMUL(REAL(0.5),(B1+B2+B3)) - dDOT(n,o1->final_posr->pos); + if (depth < 0) return 0; + + // find number of contacts requested + int maxc = flags & NUMC_MASK; + if (maxc < 1) maxc = 1; + if (maxc > 3) maxc = 3; // no more than 3 contacts per box allowed + + // find deepest point + dVector3 p; + p[0] = o1->final_posr->pos[0]; + p[1] = o1->final_posr->pos[1]; + p[2] = o1->final_posr->pos[2]; +#define FOO(i,op) \ + p[0] op dMUL(REAL(0.5),dMUL(box->side[i],R[0+i])); \ + p[1] op dMUL(REAL(0.5),dMUL(box->side[i],R[4+i])); \ + p[2] op dMUL(REAL(0.5),dMUL(box->side[i],R[8+i])); +#define BAR(i,iinc) if (A ## iinc > 0) { FOO(i,-=) } else { FOO(i,+=) } + BAR(0,1); + BAR(1,2); + BAR(2,3); +#undef FOO +#undef BAR + + // the deepest point is the first contact point + contact->pos[0] = p[0]; + contact->pos[1] = p[1]; + contact->pos[2] = p[2]; + contact->normal[0] = n[0]; + contact->normal[1] = n[1]; + contact->normal[2] = n[2]; + contact->depth = depth; + ret = 1; // ret is number of contact points found so far + if (maxc == 1) goto done; + + // get the second and third contact points by starting from `p' and going + // along the two sides with the smallest projected length. + +#define FOO(i,j,op) \ + CONTACT(contact,i*skip)->pos[0] = p[0] op dMUL(box->side[j],R[0+j]); \ + CONTACT(contact,i*skip)->pos[1] = p[1] op dMUL(box->side[j],R[4+j]); \ + CONTACT(contact,i*skip)->pos[2] = p[2] op dMUL(box->side[j],R[8+j]); +#define BAR(ctact,side,sideinc) \ + depth -= B ## sideinc; \ + if (depth < 0) goto done; \ + if (A ## sideinc > 0) { FOO(ctact,side,+) } else { FOO(ctact,side,-) } \ + CONTACT(contact,ctact*skip)->depth = depth; \ + ret++; + + CONTACT(contact,skip)->normal[0] = n[0]; + CONTACT(contact,skip)->normal[1] = n[1]; + CONTACT(contact,skip)->normal[2] = n[2]; + if (maxc == 3) { + CONTACT(contact,2*skip)->normal[0] = n[0]; + CONTACT(contact,2*skip)->normal[1] = n[1]; + CONTACT(contact,2*skip)->normal[2] = n[2]; + } + + if (B1 < B2) { + if (B3 < B1) goto use_side_3; else { + BAR(1,0,1); // use side 1 + if (maxc == 2) goto done; + if (B2 < B3) goto contact2_2; else goto contact2_3; + } + } + else { + if (B3 < B2) { + use_side_3: // use side 3 + BAR(1,2,3); + if (maxc == 2) goto done; + if (B1 < B2) goto contact2_1; else goto contact2_2; + } + else { + BAR(1,1,2); // use side 2 + if (maxc == 2) goto done; + if (B1 < B3) goto contact2_1; else goto contact2_3; + } + } + + contact2_1: BAR(2,0,1); goto done; + contact2_2: BAR(2,1,2); goto done; + contact2_3: BAR(2,2,3); goto done; +#undef FOO +#undef BAR + + done: + for (int i=0; ig1 = o1; + CONTACT(contact,i*skip)->g2 = o2; + } + return ret; +}