--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/ode/src/collision_cylinder_sphere.cpp Tue Feb 02 01:00:49 2010 +0200
@@ -0,0 +1,251 @@
+/*************************************************************************
+* *
+* 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. *
+* *
+*************************************************************************/
+
+
+/*******************************************************************
+ * *
+ * cylinder-sphere collider by Christoph Beyer (boernerb@web.de) *
+ * *
+ * In Cylinder/Sphere-collisions, there are three possibilies: *
+ * 1. collision with the cylinder's nappe *
+ * 2. collision with one of the cylinder's disc *
+ * 3. collision with one of the disc's border *
+ * *
+ * This collider computes two distances (s, t) and based on them, *
+ * it decides, which collision we have. *
+ * This collider always generates 1 (or 0, if we have no collison) *
+ * contacts. *
+ * It is able to "separate" cylinder and sphere in all *
+ * configurations, but it never pays attention to velocity. *
+ * So, in extrem situations, "tunneling-effect" is possible. *
+ * *
+ *******************************************************************/
+
+#include <ode/collision.h>
+#include <ode/matrix.h>
+#include <ode/rotation.h>
+#include <ode/odemath.h>
+#include <ode/objects.h>
+#include "collision_kernel.h" // for dxGeom
+
+int dCollideCylinderSphere(dxGeom* Cylinder, dxGeom* Sphere,
+ int /*flags*/, dContactGeom *contact, int /*skip*/)
+{
+ int GeomCount = 0; // count of used contacts
+
+ const dReal toleranz = REAL(0.0001f);
+
+ // get the data from the geoms
+ dReal radius, length;
+ dGeomCylinderGetParams(Cylinder, &radius, &length);
+ dVector3 &cylpos = Cylinder->final_posr->pos;
+ const dReal* pfRot1 = dGeomGetRotation(Cylinder);
+
+ dReal radius2;
+ radius2 = dGeomSphereGetRadius(Sphere);
+ const dReal* SpherePos = dGeomGetPosition(Sphere);
+
+ // G1Pos1 is the middle of the first disc
+ // G1Pos2 is the middle of the second disc
+ // vDir1 is the unit direction of the cylinderaxis
+ dVector3 G1Pos1, G1Pos2, vDir1;
+ vDir1[0] = Cylinder->final_posr->R[2];
+ vDir1[1] = Cylinder->final_posr->R[6];
+ vDir1[2] = Cylinder->final_posr->R[10];
+
+ dReal s;
+ s = dMUL(length,REAL(0.5)); // just a precomputed factor
+ G1Pos2[0] = dMUL(vDir1[0],s) + cylpos[0];
+ G1Pos2[1] = dMUL(vDir1[1],s) + cylpos[1];
+ G1Pos2[2] = dMUL(vDir1[2],s) + cylpos[2];
+
+ G1Pos1[0] = dMUL(vDir1[0],-s) + cylpos[0];
+ G1Pos1[1] = dMUL(vDir1[1],-s) + cylpos[1];
+ G1Pos1[2] = dMUL(vDir1[2],-s) + cylpos[2];
+
+ dVector3 C;
+ dReal t;
+ // Step 1: compute the two distances 's' and 't'
+ // 's' is the distance from the first disc (in vDir1-/Zylinderaxis-direction), the disc with G1Pos1 in the middle
+ s = dMUL((SpherePos[0] - G1Pos1[0]),vDir1[0]) - dMUL((G1Pos1[1] - SpherePos[1]),vDir1[1]) - dMUL((G1Pos1[2] - SpherePos[2]),vDir1[2]);
+ if(s < (-radius2) || s > (length + radius2) )
+ {
+ // Sphere is too far away from the discs
+ // no collision
+ return 0;
+ }
+
+ // C is the direction from Sphere-middle to the cylinder-axis (vDir1); C is orthogonal to the cylinder-axis
+ C[0] = dMUL(s,vDir1[0]) + G1Pos1[0] - SpherePos[0];
+ C[1] = dMUL(s,vDir1[1]) + G1Pos1[1] - SpherePos[1];
+ C[2] = dMUL(s,vDir1[2]) + G1Pos1[2] - SpherePos[2];
+ // t is the distance from the Sphere-middle to the cylinder-axis!
+ t = dSqrt(dMUL(C[0],C[0]) + dMUL(C[1],C[1]) + dMUL(C[2],C[2]) );
+ if(t > (radius + radius2) )
+ {
+ // Sphere is too far away from the cylinder axis!
+ // no collision
+ return 0;
+ }
+
+ // decide which kind of collision we have:
+ if(t > radius && (s < 0 || s > length) )
+ {
+ // 3. collision
+ if(s <= 0)
+ {
+ contact->depth = radius2 - dSqrt( dMUL(s,s) + dMUL((t - radius),(t - radius)) );
+ if(contact->depth < 0)
+ {
+ // no collision!
+ return 0;
+ }
+ contact->pos[0] = dMUL(dDIV(C[0],t),-radius) + G1Pos1[0];
+ contact->pos[1] = dMUL(dDIV(C[1],t),-radius) + G1Pos1[1];
+ contact->pos[2] = dMUL(dDIV(C[2],t),-radius) + G1Pos1[2];
+ contact->normal[0] = dDIV((contact->pos[0] - SpherePos[0]),(radius2 - contact->depth));
+ contact->normal[1] = dDIV((contact->pos[1] - SpherePos[1]),(radius2 - contact->depth));
+ contact->normal[2] = dDIV((contact->pos[2] - SpherePos[2]),(radius2 - contact->depth));
+ contact->g1 = Cylinder;
+ contact->g2 = Sphere;
+ GeomCount++;
+ return GeomCount;
+ }
+ else
+ {
+ // now s is bigger than length here!
+ contact->depth = radius2 - dSqrt( dMUL((s - length),(s - length)) + dMUL((t - radius),(t - radius)) );
+ if(contact->depth < 0)
+ {
+ // no collision!
+ return 0;
+ }
+ contact->pos[0] = dMUL(dDIV(C[0],t),-radius) + G1Pos2[0];
+ contact->pos[1] = dMUL(dDIV(C[1],t),-radius) + G1Pos2[1];
+ contact->pos[2] = dMUL(dDIV(C[2],t),-radius) + G1Pos2[2];
+ contact->normal[0] = dDIV((contact->pos[0] - SpherePos[0]),(radius2 - contact->depth));
+ contact->normal[1] = dDIV((contact->pos[1] - SpherePos[1]),(radius2 - contact->depth));
+ contact->normal[2] = dDIV((contact->pos[2] - SpherePos[2]),(radius2 - contact->depth));
+ contact->g1 = Cylinder;
+ contact->g2 = Sphere;
+ GeomCount++;
+ return GeomCount;
+ }
+ }
+ else if( (radius - t) <= s && (radius - t) <= (length - s) )
+ {
+ // 1. collsision
+ if(t > (radius2 + toleranz))
+ {
+ // cylinder-axis is outside the sphere
+ contact->depth = (radius2 + radius) - t;
+ if(contact->depth < 0)
+ {
+ // should never happen, but just for safeness
+ return 0;
+ }
+ else
+ {
+ C[0] = dDIV(C[0],t);
+ C[1] = dDIV(C[1],t);
+ C[2] = dDIV(C[2],t);
+ contact->pos[0] = dMUL(C[0],radius2) + SpherePos[0];
+ contact->pos[1] = dMUL(C[1],radius2) + SpherePos[1];
+ contact->pos[2] = dMUL(C[2],radius2) + SpherePos[2];
+ contact->normal[0] = C[0];
+ contact->normal[1] = C[1];
+ contact->normal[2] = C[2];
+ contact->g1 = Cylinder;
+ contact->g2 = Sphere;
+ GeomCount++;
+ return GeomCount;
+ }
+ }
+ else
+ {
+ // cylinder-axis is outside of the sphere
+ contact->depth = (radius2 + radius) - t;
+ if(contact->depth < 0)
+ {
+ // should never happen, but just for safeness
+ return 0;
+ }
+ else
+ {
+ contact->pos[0] = C[0] + SpherePos[0];
+ contact->pos[1] = C[1] + SpherePos[1];
+ contact->pos[2] = C[2] + SpherePos[2];
+ contact->normal[0] = dDIV(C[0],t);
+ contact->normal[1] = dDIV(C[1],t);
+ contact->normal[2] = dDIV(C[2],t);
+ contact->g1 = Cylinder;
+ contact->g2 = Sphere;
+ GeomCount++;
+ return GeomCount;
+ }
+ }
+ }
+ else
+ {
+ // 2. collision
+ if(s <= dMUL(length,REAL(0.5)) )
+ {
+ // collsision with the first disc
+ contact->depth = s + radius2;
+ if(contact->depth < 0)
+ {
+ // should never happen, but just for safeness
+ return 0;
+ }
+ contact->pos[0] = dMUL(radius2,vDir1[0]) + SpherePos[0];
+ contact->pos[1] = dMUL(radius2,vDir1[1]) + SpherePos[1];
+ contact->pos[2] = dMUL(radius2,vDir1[2]) + SpherePos[2];
+ contact->normal[0] = vDir1[0];
+ contact->normal[1] = vDir1[1];
+ contact->normal[2] = vDir1[2];
+ contact->g1 = Cylinder;
+ contact->g2 = Sphere;
+ GeomCount++;
+ return GeomCount;
+ }
+ else
+ {
+ // collsision with the second disc
+ contact->depth = (radius2 + length - s);
+ if(contact->depth < 0)
+ {
+ // should never happen, but just for safeness
+ return 0;
+ }
+ contact->pos[0] = dMUL(radius2,-vDir1[0]) + SpherePos[0];
+ contact->pos[1] = dMUL(radius2,-vDir1[1]) + SpherePos[1];
+ contact->pos[2] = dMUL(radius2,-vDir1[2]) + SpherePos[2];
+ contact->normal[0] = -vDir1[0];
+ contact->normal[1] = -vDir1[1];
+ contact->normal[2] = -vDir1[2];
+ contact->g1 = Cylinder;
+ contact->g2 = Sphere;
+ GeomCount++;
+ return GeomCount;
+ }
+ }
+}