613 lines
19 KiB
C++
613 lines
19 KiB
C++
/*************************************************************************
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* *
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* Open Dynamics Engine, Copyright (C) 2001,2002 Russell L. Smith. *
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* All rights reserved. Email: russ@q12.org Web: www.q12.org *
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* *
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* This library is free software; you can redistribute it and/or *
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* modify it under the terms of EITHER: *
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* (1) The GNU Lesser General Public License as published by the Free *
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* Software Foundation; either version 2.1 of the License, or (at *
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* your option) any later version. The text of the GNU Lesser *
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* General Public License is included with this library in the *
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* file LICENSE.TXT. *
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* (2) The BSD-style license that is included with this library in *
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* the file LICENSE-BSD.TXT. *
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* *
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* This library is distributed in the hope that it will be useful, *
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* but WITHOUT ANY WARRANTY; without even the implied warranty of *
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the files *
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* LICENSE.TXT and LICENSE-BSD.TXT for more details. *
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* *
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*************************************************************************/
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/*
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some useful collision utility stuff. this includes some API utility
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functions that are defined in the public header files.
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*/
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#include <ode/common.h>
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#include <ode/collision.h>
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#include <ode/odemath.h>
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#include "collision_util.h"
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//****************************************************************************
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int dCollideSpheres (dVector3 p1, dReal r1,
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dVector3 p2, dReal r2, dContactGeom *c)
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{
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// printf ("d=%.2f (%.2f %.2f %.2f) (%.2f %.2f %.2f) r1=%.2f r2=%.2f\n",
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// d,p1[0],p1[1],p1[2],p2[0],p2[1],p2[2],r1,r2);
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dReal d = dDISTANCE (p1,p2);
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if (d > (r1 + r2)) return 0;
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if (d <= 0) {
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c->pos[0] = p1[0];
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c->pos[1] = p1[1];
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c->pos[2] = p1[2];
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c->normal[0] = 1;
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c->normal[1] = 0;
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c->normal[2] = 0;
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c->depth = r1 + r2;
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}
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else {
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dReal d1 = dRecip (d);
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c->normal[0] = (p1[0]-p2[0])*d1;
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c->normal[1] = (p1[1]-p2[1])*d1;
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c->normal[2] = (p1[2]-p2[2])*d1;
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dReal k = REAL(0.5) * (r2 - r1 - d);
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c->pos[0] = p1[0] + c->normal[0]*k;
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c->pos[1] = p1[1] + c->normal[1]*k;
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c->pos[2] = p1[2] + c->normal[2]*k;
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c->depth = r1 + r2 - d;
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}
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return 1;
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}
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void dLineClosestApproach (const dVector3 pa, const dVector3 ua,
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const dVector3 pb, const dVector3 ub,
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dReal *alpha, dReal *beta)
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{
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dVector3 p;
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p[0] = pb[0] - pa[0];
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p[1] = pb[1] - pa[1];
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p[2] = pb[2] - pa[2];
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dReal uaub = dDOT(ua,ub);
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dReal q1 = dDOT(ua,p);
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dReal q2 = -dDOT(ub,p);
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dReal d = 1-uaub*uaub;
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if (d <= REAL(0.0001)) {
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// @@@ this needs to be made more robust
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*alpha = 0;
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*beta = 0;
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}
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else {
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d = dRecip(d);
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*alpha = (q1 + uaub*q2)*d;
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*beta = (uaub*q1 + q2)*d;
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}
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}
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// given two line segments A and B with endpoints a1-a2 and b1-b2, return the
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// points on A and B that are closest to each other (in cp1 and cp2).
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// in the case of parallel lines where there are multiple solutions, a
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// solution involving the endpoint of at least one line will be returned.
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// this will work correctly for zero length lines, e.g. if a1==a2 and/or
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// b1==b2.
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//
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// the algorithm works by applying the voronoi clipping rule to the features
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// of the line segments. the three features of each line segment are the two
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// endpoints and the line between them. the voronoi clipping rule states that,
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// for feature X on line A and feature Y on line B, the closest points PA and
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// PB between X and Y are globally the closest points if PA is in V(Y) and
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// PB is in V(X), where V(X) is the voronoi region of X.
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void dClosestLineSegmentPoints (const dVector3 a1, const dVector3 a2,
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const dVector3 b1, const dVector3 b2,
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dVector3 cp1, dVector3 cp2)
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{
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dVector3 a1a2,b1b2,a1b1,a1b2,a2b1,a2b2,n;
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dReal la,lb,k,da1,da2,da3,da4,db1,db2,db3,db4,det;
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#define SET2(a,b) a[0]=b[0]; a[1]=b[1]; a[2]=b[2];
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#define SET3(a,b,op,c) a[0]=b[0] op c[0]; a[1]=b[1] op c[1]; a[2]=b[2] op c[2];
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// check vertex-vertex features
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SET3 (a1a2,a2,-,a1);
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SET3 (b1b2,b2,-,b1);
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SET3 (a1b1,b1,-,a1);
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da1 = dDOT(a1a2,a1b1);
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db1 = dDOT(b1b2,a1b1);
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if (da1 <= 0 && db1 >= 0) {
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SET2 (cp1,a1);
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SET2 (cp2,b1);
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return;
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}
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SET3 (a1b2,b2,-,a1);
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da2 = dDOT(a1a2,a1b2);
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db2 = dDOT(b1b2,a1b2);
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if (da2 <= 0 && db2 <= 0) {
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SET2 (cp1,a1);
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SET2 (cp2,b2);
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return;
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}
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SET3 (a2b1,b1,-,a2);
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da3 = dDOT(a1a2,a2b1);
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db3 = dDOT(b1b2,a2b1);
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if (da3 >= 0 && db3 >= 0) {
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SET2 (cp1,a2);
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SET2 (cp2,b1);
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return;
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}
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SET3 (a2b2,b2,-,a2);
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da4 = dDOT(a1a2,a2b2);
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db4 = dDOT(b1b2,a2b2);
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if (da4 >= 0 && db4 <= 0) {
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SET2 (cp1,a2);
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SET2 (cp2,b2);
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return;
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}
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// check edge-vertex features.
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// if one or both of the lines has zero length, we will never get to here,
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// so we do not have to worry about the following divisions by zero.
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la = dDOT(a1a2,a1a2);
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if (da1 >= 0 && da3 <= 0) {
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k = da1 / la;
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SET3 (n,a1b1,-,k*a1a2);
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if (dDOT(b1b2,n) >= 0) {
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SET3 (cp1,a1,+,k*a1a2);
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SET2 (cp2,b1);
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return;
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}
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}
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if (da2 >= 0 && da4 <= 0) {
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k = da2 / la;
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SET3 (n,a1b2,-,k*a1a2);
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if (dDOT(b1b2,n) <= 0) {
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SET3 (cp1,a1,+,k*a1a2);
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SET2 (cp2,b2);
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return;
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}
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}
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lb = dDOT(b1b2,b1b2);
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if (db1 <= 0 && db2 >= 0) {
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k = -db1 / lb;
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SET3 (n,-a1b1,-,k*b1b2);
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if (dDOT(a1a2,n) >= 0) {
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SET2 (cp1,a1);
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SET3 (cp2,b1,+,k*b1b2);
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return;
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}
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}
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if (db3 <= 0 && db4 >= 0) {
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k = -db3 / lb;
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SET3 (n,-a2b1,-,k*b1b2);
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if (dDOT(a1a2,n) <= 0) {
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SET2 (cp1,a2);
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SET3 (cp2,b1,+,k*b1b2);
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return;
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}
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}
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// it must be edge-edge
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k = dDOT(a1a2,b1b2);
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det = la*lb - k*k;
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if (det <= 0) {
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// this should never happen, but just in case...
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SET2(cp1,a1);
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SET2(cp2,b1);
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return;
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}
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det = dRecip (det);
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dReal alpha = (lb*da1 - k*db1) * det;
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dReal beta = ( k*da1 - la*db1) * det;
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SET3 (cp1,a1,+,alpha*a1a2);
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SET3 (cp2,b1,+,beta*b1b2);
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# undef SET2
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# undef SET3
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}
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// a simple root finding algorithm is used to find the value of 't' that
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// satisfies:
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// d|D(t)|^2/dt = 0
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// where:
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// |D(t)| = |p(t)-b(t)|
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// where p(t) is a point on the line parameterized by t:
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// p(t) = p1 + t*(p2-p1)
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// and b(t) is that same point clipped to the boundary of the box. in box-
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// relative coordinates d|D(t)|^2/dt is the sum of three x,y,z components
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// each of which looks like this:
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//
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// t_lo /
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// ______/ -->t
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// / t_hi
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// /
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//
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// t_lo and t_hi are the t values where the line passes through the planes
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// corresponding to the sides of the box. the algorithm computes d|D(t)|^2/dt
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// in a piecewise fashion from t=0 to t=1, stopping at the point where
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// d|D(t)|^2/dt crosses from negative to positive.
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void dClosestLineBoxPoints (const dVector3 p1, const dVector3 p2,
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const dVector3 c, const dMatrix3 R,
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const dVector3 side,
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dVector3 lret, dVector3 bret)
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{
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int i;
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// compute the start and delta of the line p1-p2 relative to the box.
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// we will do all subsequent computations in this box-relative coordinate
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// system. we have to do a translation and rotation for each point.
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dVector3 tmp,s,v;
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tmp[0] = p1[0] - c[0];
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tmp[1] = p1[1] - c[1];
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tmp[2] = p1[2] - c[2];
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dMULTIPLY1_331 (s,R,tmp);
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tmp[0] = p2[0] - p1[0];
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tmp[1] = p2[1] - p1[1];
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tmp[2] = p2[2] - p1[2];
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dMULTIPLY1_331 (v,R,tmp);
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// mirror the line so that v has all components >= 0
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dVector3 sign;
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for (i=0; i<3; i++) {
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if (v[i] < 0) {
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s[i] = -s[i];
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v[i] = -v[i];
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sign[i] = -1;
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}
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else sign[i] = 1;
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}
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// compute v^2
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dVector3 v2;
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v2[0] = v[0]*v[0];
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v2[1] = v[1]*v[1];
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v2[2] = v[2]*v[2];
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// compute the half-sides of the box
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dReal h[3];
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h[0] = REAL(0.5) * side[0];
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h[1] = REAL(0.5) * side[1];
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h[2] = REAL(0.5) * side[2];
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// region is -1,0,+1 depending on which side of the box planes each
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// coordinate is on. tanchor is the next t value at which there is a
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// transition, or the last one if there are no more.
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int region[3];
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dReal tanchor[3];
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// Denormals are a problem, because we divide by v[i], and then
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// multiply that by 0. Alas, infinity times 0 is infinity (!)
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// We also use v2[i], which is v[i] squared. Here's how the epsilons
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// are chosen:
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// float epsilon = 1.175494e-038 (smallest non-denormal number)
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// double epsilon = 2.225074e-308 (smallest non-denormal number)
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// For single precision, choose an epsilon such that v[i] squared is
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// not a denormal; this is for performance.
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// For double precision, choose an epsilon such that v[i] is not a
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// denormal; this is for correctness. (Jon Watte on mailinglist)
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#if defined( dSINGLE )
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const dReal tanchor_eps = 1e-19;
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#else
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const dReal tanchor_eps = 1e-307;
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#endif
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// find the region and tanchor values for p1
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for (i=0; i<3; i++) {
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if (v[i] > tanchor_eps) {
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if (s[i] < -h[i]) {
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region[i] = -1;
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tanchor[i] = (-h[i]-s[i])/v[i];
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}
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else {
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region[i] = (s[i] > h[i]);
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tanchor[i] = (h[i]-s[i])/v[i];
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}
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}
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else {
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region[i] = 0;
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tanchor[i] = 2; // this will never be a valid tanchor
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}
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}
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// compute d|d|^2/dt for t=0. if it's >= 0 then p1 is the closest point
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dReal t=0;
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dReal dd2dt = 0;
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for (i=0; i<3; i++) dd2dt -= (region[i] ? v2[i] : 0) * tanchor[i];
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if (dd2dt >= 0) goto got_answer;
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do {
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// find the point on the line that is at the next clip plane boundary
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dReal next_t = 1;
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for (i=0; i<3; i++) {
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if (tanchor[i] > t && tanchor[i] < 1 && tanchor[i] < next_t)
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next_t = tanchor[i];
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}
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// compute d|d|^2/dt for the next t
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dReal next_dd2dt = 0;
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for (i=0; i<3; i++) {
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next_dd2dt += (region[i] ? v2[i] : 0) * (next_t - tanchor[i]);
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}
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// if the sign of d|d|^2/dt has changed, solution = the crossover point
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if (next_dd2dt >= 0) {
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dReal m = (next_dd2dt-dd2dt)/(next_t - t);
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t -= dd2dt/m;
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goto got_answer;
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}
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// advance to the next anchor point / region
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for (i=0; i<3; i++) {
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if (tanchor[i] == next_t) {
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tanchor[i] = (h[i]-s[i])/v[i];
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region[i]++;
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}
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}
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t = next_t;
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dd2dt = next_dd2dt;
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}
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while (t < 1);
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t = 1;
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got_answer:
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// compute closest point on the line
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for (i=0; i<3; i++) lret[i] = p1[i] + t*tmp[i]; // note: tmp=p2-p1
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// compute closest point on the box
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for (i=0; i<3; i++) {
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tmp[i] = sign[i] * (s[i] + t*v[i]);
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if (tmp[i] < -h[i]) tmp[i] = -h[i];
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else if (tmp[i] > h[i]) tmp[i] = h[i];
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}
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dMULTIPLY0_331 (s,R,tmp);
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for (i=0; i<3; i++) bret[i] = s[i] + c[i];
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}
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// given boxes (p1,R1,side1) and (p1,R1,side1), return 1 if they intersect
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// or 0 if not.
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int dBoxTouchesBox (const dVector3 p1, const dMatrix3 R1,
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const dVector3 side1, const dVector3 p2,
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const dMatrix3 R2, const dVector3 side2)
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{
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// two boxes are disjoint if (and only if) there is a separating axis
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// perpendicular to a face from one box or perpendicular to an edge from
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// either box. the following tests are derived from:
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// "OBB Tree: A Hierarchical Structure for Rapid Interference Detection",
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// S.Gottschalk, M.C.Lin, D.Manocha., Proc of ACM Siggraph 1996.
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// Rij is R1'*R2, i.e. the relative rotation between R1 and R2.
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// Qij is abs(Rij)
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dVector3 p,pp;
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dReal A1,A2,A3,B1,B2,B3,R11,R12,R13,R21,R22,R23,R31,R32,R33,
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Q11,Q12,Q13,Q21,Q22,Q23,Q31,Q32,Q33;
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// get vector from centers of box 1 to box 2, relative to box 1
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p[0] = p2[0] - p1[0];
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p[1] = p2[1] - p1[1];
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p[2] = p2[2] - p1[2];
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dMULTIPLY1_331 (pp,R1,p); // get pp = p relative to body 1
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// get side lengths / 2
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A1 = side1[0]*REAL(0.5); A2 = side1[1]*REAL(0.5); A3 = side1[2]*REAL(0.5);
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B1 = side2[0]*REAL(0.5); B2 = side2[1]*REAL(0.5); B3 = side2[2]*REAL(0.5);
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// for the following tests, excluding computation of Rij, in the worst case,
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// 15 compares, 60 adds, 81 multiplies, and 24 absolutes.
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// notation: R1=[u1 u2 u3], R2=[v1 v2 v3]
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// separating axis = u1,u2,u3
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R11 = dDOT44(R1+0,R2+0); R12 = dDOT44(R1+0,R2+1); R13 = dDOT44(R1+0,R2+2);
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Q11 = dFabs(R11); Q12 = dFabs(R12); Q13 = dFabs(R13);
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if (dFabs(pp[0]) > (A1 + B1*Q11 + B2*Q12 + B3*Q13)) return 0;
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R21 = dDOT44(R1+1,R2+0); R22 = dDOT44(R1+1,R2+1); R23 = dDOT44(R1+1,R2+2);
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Q21 = dFabs(R21); Q22 = dFabs(R22); Q23 = dFabs(R23);
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if (dFabs(pp[1]) > (A2 + B1*Q21 + B2*Q22 + B3*Q23)) return 0;
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R31 = dDOT44(R1+2,R2+0); R32 = dDOT44(R1+2,R2+1); R33 = dDOT44(R1+2,R2+2);
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Q31 = dFabs(R31); Q32 = dFabs(R32); Q33 = dFabs(R33);
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if (dFabs(pp[2]) > (A3 + B1*Q31 + B2*Q32 + B3*Q33)) return 0;
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// separating axis = v1,v2,v3
|
|
if (dFabs(dDOT41(R2+0,p)) > (A1*Q11 + A2*Q21 + A3*Q31 + B1)) return 0;
|
|
if (dFabs(dDOT41(R2+1,p)) > (A1*Q12 + A2*Q22 + A3*Q32 + B2)) return 0;
|
|
if (dFabs(dDOT41(R2+2,p)) > (A1*Q13 + A2*Q23 + A3*Q33 + B3)) return 0;
|
|
|
|
// separating axis = u1 x (v1,v2,v3)
|
|
if (dFabs(pp[2]*R21-pp[1]*R31) > A2*Q31 + A3*Q21 + B2*Q13 + B3*Q12) return 0;
|
|
if (dFabs(pp[2]*R22-pp[1]*R32) > A2*Q32 + A3*Q22 + B1*Q13 + B3*Q11) return 0;
|
|
if (dFabs(pp[2]*R23-pp[1]*R33) > A2*Q33 + A3*Q23 + B1*Q12 + B2*Q11) return 0;
|
|
|
|
// separating axis = u2 x (v1,v2,v3)
|
|
if (dFabs(pp[0]*R31-pp[2]*R11) > A1*Q31 + A3*Q11 + B2*Q23 + B3*Q22) return 0;
|
|
if (dFabs(pp[0]*R32-pp[2]*R12) > A1*Q32 + A3*Q12 + B1*Q23 + B3*Q21) return 0;
|
|
if (dFabs(pp[0]*R33-pp[2]*R13) > A1*Q33 + A3*Q13 + B1*Q22 + B2*Q21) return 0;
|
|
|
|
// separating axis = u3 x (v1,v2,v3)
|
|
if (dFabs(pp[1]*R11-pp[0]*R21) > A1*Q21 + A2*Q11 + B2*Q33 + B3*Q32) return 0;
|
|
if (dFabs(pp[1]*R12-pp[0]*R22) > A1*Q22 + A2*Q12 + B1*Q33 + B3*Q31) return 0;
|
|
if (dFabs(pp[1]*R13-pp[0]*R23) > A1*Q23 + A2*Q13 + B1*Q32 + B2*Q31) return 0;
|
|
|
|
return 1;
|
|
}
|
|
|
|
//****************************************************************************
|
|
// other utility functions
|
|
|
|
void dInfiniteAABB (dxGeom *geom, dReal aabb[6])
|
|
{
|
|
aabb[0] = -dInfinity;
|
|
aabb[1] = dInfinity;
|
|
aabb[2] = -dInfinity;
|
|
aabb[3] = dInfinity;
|
|
aabb[4] = -dInfinity;
|
|
aabb[5] = dInfinity;
|
|
}
|
|
|
|
|
|
//****************************************************************************
|
|
// Helpers for Croteam's collider - by Nguyen Binh
|
|
|
|
int dClipEdgeToPlane( dVector3 &vEpnt0, dVector3 &vEpnt1, const dVector4& plPlane)
|
|
{
|
|
// calculate distance of edge points to plane
|
|
dReal fDistance0 = dPointPlaneDistance( vEpnt0 ,plPlane );
|
|
dReal fDistance1 = dPointPlaneDistance( vEpnt1 ,plPlane );
|
|
|
|
// if both points are behind the plane
|
|
if ( fDistance0 < 0 && fDistance1 < 0 )
|
|
{
|
|
// do nothing
|
|
return 0;
|
|
// if both points in front of the plane
|
|
}
|
|
else if ( fDistance0 > 0 && fDistance1 > 0 )
|
|
{
|
|
// accept them
|
|
return 1;
|
|
// if we have edge/plane intersection
|
|
} else if ((fDistance0 > 0 && fDistance1 < 0) || ( fDistance0 < 0 && fDistance1 > 0))
|
|
{
|
|
|
|
// find intersection point of edge and plane
|
|
dVector3 vIntersectionPoint;
|
|
vIntersectionPoint[0]= vEpnt0[0]-(vEpnt0[0]-vEpnt1[0])*fDistance0/(fDistance0-fDistance1);
|
|
vIntersectionPoint[1]= vEpnt0[1]-(vEpnt0[1]-vEpnt1[1])*fDistance0/(fDistance0-fDistance1);
|
|
vIntersectionPoint[2]= vEpnt0[2]-(vEpnt0[2]-vEpnt1[2])*fDistance0/(fDistance0-fDistance1);
|
|
|
|
// clamp correct edge to intersection point
|
|
if ( fDistance0 < 0 )
|
|
{
|
|
dVector3Copy(vIntersectionPoint,vEpnt0);
|
|
} else
|
|
{
|
|
dVector3Copy(vIntersectionPoint,vEpnt1);
|
|
}
|
|
return 1;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
// clip polygon with plane and generate new polygon points
|
|
void dClipPolyToPlane( const dVector3 avArrayIn[], const int ctIn,
|
|
dVector3 avArrayOut[], int &ctOut,
|
|
const dVector4 &plPlane )
|
|
{
|
|
// start with no output points
|
|
ctOut = 0;
|
|
|
|
int i0 = ctIn-1;
|
|
|
|
// for each edge in input polygon
|
|
for (int i1=0; i1<ctIn; i0=i1, i1++) {
|
|
|
|
|
|
// calculate distance of edge points to plane
|
|
dReal fDistance0 = dPointPlaneDistance( avArrayIn[i0],plPlane );
|
|
dReal fDistance1 = dPointPlaneDistance( avArrayIn[i1],plPlane );
|
|
|
|
// if first point is in front of plane
|
|
if( fDistance0 >= 0 ) {
|
|
// emit point
|
|
avArrayOut[ctOut][0] = avArrayIn[i0][0];
|
|
avArrayOut[ctOut][1] = avArrayIn[i0][1];
|
|
avArrayOut[ctOut][2] = avArrayIn[i0][2];
|
|
ctOut++;
|
|
}
|
|
|
|
// if points are on different sides
|
|
if( (fDistance0 > 0 && fDistance1 < 0) || ( fDistance0 < 0 && fDistance1 > 0) ) {
|
|
|
|
// find intersection point of edge and plane
|
|
dVector3 vIntersectionPoint;
|
|
vIntersectionPoint[0]= avArrayIn[i0][0] -
|
|
(avArrayIn[i0][0]-avArrayIn[i1][0])*fDistance0/(fDistance0-fDistance1);
|
|
vIntersectionPoint[1]= avArrayIn[i0][1] -
|
|
(avArrayIn[i0][1]-avArrayIn[i1][1])*fDistance0/(fDistance0-fDistance1);
|
|
vIntersectionPoint[2]= avArrayIn[i0][2] -
|
|
(avArrayIn[i0][2]-avArrayIn[i1][2])*fDistance0/(fDistance0-fDistance1);
|
|
|
|
// emit intersection point
|
|
avArrayOut[ctOut][0] = vIntersectionPoint[0];
|
|
avArrayOut[ctOut][1] = vIntersectionPoint[1];
|
|
avArrayOut[ctOut][2] = vIntersectionPoint[2];
|
|
ctOut++;
|
|
}
|
|
}
|
|
|
|
}
|
|
|
|
void dClipPolyToCircle(const dVector3 avArrayIn[], const int ctIn,
|
|
dVector3 avArrayOut[], int &ctOut,
|
|
const dVector4 &plPlane ,dReal fRadius)
|
|
{
|
|
// start with no output points
|
|
ctOut = 0;
|
|
|
|
int i0 = ctIn-1;
|
|
|
|
// for each edge in input polygon
|
|
for (int i1=0; i1<ctIn; i0=i1, i1++)
|
|
{
|
|
// calculate distance of edge points to plane
|
|
dReal fDistance0 = dPointPlaneDistance( avArrayIn[i0],plPlane );
|
|
dReal fDistance1 = dPointPlaneDistance( avArrayIn[i1],plPlane );
|
|
|
|
// if first point is in front of plane
|
|
if( fDistance0 >= 0 )
|
|
{
|
|
// emit point
|
|
if (dVector3Length2(avArrayIn[i0]) <= fRadius*fRadius)
|
|
{
|
|
avArrayOut[ctOut][0] = avArrayIn[i0][0];
|
|
avArrayOut[ctOut][1] = avArrayIn[i0][1];
|
|
avArrayOut[ctOut][2] = avArrayIn[i0][2];
|
|
ctOut++;
|
|
}
|
|
}
|
|
|
|
// if points are on different sides
|
|
if( (fDistance0 > 0 && fDistance1 < 0) || ( fDistance0 < 0 && fDistance1 > 0) )
|
|
{
|
|
|
|
// find intersection point of edge and plane
|
|
dVector3 vIntersectionPoint;
|
|
vIntersectionPoint[0]= avArrayIn[i0][0] -
|
|
(avArrayIn[i0][0]-avArrayIn[i1][0])*fDistance0/(fDistance0-fDistance1);
|
|
vIntersectionPoint[1]= avArrayIn[i0][1] -
|
|
(avArrayIn[i0][1]-avArrayIn[i1][1])*fDistance0/(fDistance0-fDistance1);
|
|
vIntersectionPoint[2]= avArrayIn[i0][2] -
|
|
(avArrayIn[i0][2]-avArrayIn[i1][2])*fDistance0/(fDistance0-fDistance1);
|
|
|
|
// emit intersection point
|
|
if (dVector3Length2(avArrayIn[i0]) <= fRadius*fRadius)
|
|
{
|
|
avArrayOut[ctOut][0] = vIntersectionPoint[0];
|
|
avArrayOut[ctOut][1] = vIntersectionPoint[1];
|
|
avArrayOut[ctOut][2] = vIntersectionPoint[2];
|
|
ctOut++;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|