315 lines
8.5 KiB
C++
315 lines
8.5 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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// Test for breaking joints, by Bram Stolk
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#include <ode/config.h>
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#include <assert.h>
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#ifdef HAVE_UNISTD_H
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#include <unistd.h>
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#endif
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#include <ode/ode.h>
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#include <drawstuff/drawstuff.h>
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#ifdef _MSC_VER
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#pragma warning(disable:4244 4305) // for VC++, no precision loss complaints
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#endif
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#ifdef dDOUBLE
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#define dsDrawBox dsDrawBoxD
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#define dsDrawCylinder dsDrawCylinderD
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#endif
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// dynamics and collision objects (chassis, 3 wheels, environment)
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static dWorldID world;
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static dSpaceID space;
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static const int STACKCNT=10; // nr of weights on bridge
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static const int SEGMCNT=16; // nr of segments in bridge
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static const float SEGMDIM[3] = { 0.9, 4, 0.1 };
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static dGeomID groundgeom;
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static dBodyID segbodies[SEGMCNT];
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static dGeomID seggeoms[SEGMCNT];
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static dBodyID stackbodies[STACKCNT];
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static dGeomID stackgeoms[STACKCNT];
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static dJointID hinges[SEGMCNT-1];
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static dJointID sliders[2];
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static dJointFeedback jfeedbacks[SEGMCNT-1];
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static dReal colours[SEGMCNT];
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static int stress[SEGMCNT-1];
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static dJointGroupID contactgroup;
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// this is called by dSpaceCollide when two objects in space are
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// potentially colliding.
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static void nearCallback (void *data, dGeomID o1, dGeomID o2)
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{
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assert(o1);
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assert(o2);
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if (dGeomIsSpace(o1) || dGeomIsSpace(o2))
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{
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fprintf(stderr,"testing space %p %p\n", o1,o2);
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// colliding a space with something
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dSpaceCollide2(o1,o2,data,&nearCallback);
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// Note we do not want to test intersections within a space,
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// only between spaces.
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return;
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}
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const int N = 32;
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dContact contact[N];
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int n = dCollide (o1,o2,N,&(contact[0].geom),sizeof(dContact));
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if (n > 0)
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{
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for (int i=0; i<n; i++)
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{
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contact[i].surface.mode = dContactSoftERP | dContactSoftCFM | dContactApprox1;
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contact[i].surface.mu = 100.0;
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contact[i].surface.soft_erp = 0.96;
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contact[i].surface.soft_cfm = 0.02;
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dJointID c = dJointCreateContact (world,contactgroup,&contact[i]);
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dJointAttach (c,
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dGeomGetBody(contact[i].geom.g1),
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dGeomGetBody(contact[i].geom.g2));
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}
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}
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}
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// start simulation - set viewpoint
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static void start()
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{
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static float xyz[3] = { -6, 8, 6};
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static float hpr[3] = { -65.0f, -27.0f, 0.0f};
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dsSetViewpoint (xyz,hpr);
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}
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// called when a key pressed
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static void command (int cmd)
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{
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}
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void drawGeom (dGeomID g)
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{
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const dReal *pos = dGeomGetPosition(g);
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const dReal *R = dGeomGetRotation(g);
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int type = dGeomGetClass (g);
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if (type == dBoxClass)
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{
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dVector3 sides;
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dGeomBoxGetLengths (g, sides);
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dsDrawBox (pos,R,sides);
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}
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if (type == dCylinderClass)
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{
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dReal r,l;
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dGeomCylinderGetParams(g, &r, &l);
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dsDrawCylinder (pos, R, l, r);
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}
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}
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static void inspectJoints(void)
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{
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const dReal forcelimit = 2000.0;
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int i;
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for (i=0; i<SEGMCNT-1; i++)
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{
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if (dJointGetBody(hinges[i], 0))
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{
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// This joint has not snapped already... inspect it.
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dReal l0 = dLENGTH(jfeedbacks[i].f1);
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dReal l1 = dLENGTH(jfeedbacks[i].f2);
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colours[i+0] = 0.95*colours[i+0] + 0.05 * l0/forcelimit;
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colours[i+1] = 0.95*colours[i+1] + 0.05 * l1/forcelimit;
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if (l0 > forcelimit || l1 > forcelimit)
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stress[i]++;
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else
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stress[i]=0;
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if (stress[i]>4)
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{
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// Low-pass filter the noisy feedback data.
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// Only after 4 consecutive timesteps with excessive load, snap.
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fprintf(stderr,"SNAP! (that was the sound of joint %d breaking)\n", i);
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dJointAttach (hinges[i], 0, 0);
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}
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}
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}
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}
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// simulation loop
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static void simLoop (int pause)
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{
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int i;
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double simstep = 0.005; // 5ms simulation steps
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double dt = dsElapsedTime();
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int nrofsteps = (int) ceilf(dt/simstep);
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for (i=0; i<nrofsteps && !pause; i++)
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{
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dSpaceCollide (space,0,&nearCallback);
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dWorldQuickStep (world, simstep);
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dJointGroupEmpty (contactgroup);
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inspectJoints();
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}
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for (i=0; i<SEGMCNT; i++)
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{
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float r=0,g=0,b=0.2;
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float v = colours[i];
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if (v>1.0) v=1.0;
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if (v<0.5)
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{
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r=2*v;
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g=1.0;
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}
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else
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{
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r=1.0;
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g=2*(1.0-v);
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}
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dsSetColor (r,g,b);
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drawGeom(seggeoms[i]);
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}
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dsSetColor (1,1,1);
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for (i=0; i<STACKCNT; i++)
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drawGeom(stackgeoms[i]);
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}
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int main (int argc, char **argv)
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{
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dMass m;
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// setup pointers to drawstuff callback functions
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dsFunctions fn;
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fn.version = DS_VERSION;
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fn.start = &start;
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fn.step = &simLoop;
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fn.command = &command;
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fn.stop = 0;
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fn.path_to_textures = "../../drawstuff/textures";
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if(argc==2)
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{
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fn.path_to_textures = argv[1];
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}
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// create world
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dInitODE();
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world = dWorldCreate();
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space = dHashSpaceCreate (0);
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contactgroup = dJointGroupCreate (0);
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dWorldSetGravity (world,0,0,-9.8);
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dWorldSetQuickStepNumIterations (world, 20);
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int i;
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for (i=0; i<SEGMCNT; i++)
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{
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segbodies[i] = dBodyCreate (world);
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dBodySetPosition(segbodies[i], i - SEGMCNT/2.0, 0, 5);
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dMassSetBox (&m, 1, SEGMDIM[0], SEGMDIM[1], SEGMDIM[2]);
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dBodySetMass (segbodies[i], &m);
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seggeoms[i] = dCreateBox (0, SEGMDIM[0], SEGMDIM[1], SEGMDIM[2]);
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dGeomSetBody (seggeoms[i], segbodies[i]);
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dSpaceAdd (space, seggeoms[i]);
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}
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for (i=0; i<SEGMCNT-1; i++)
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{
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hinges[i] = dJointCreateHinge (world,0);
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dJointAttach (hinges[i], segbodies[i],segbodies[i+1]);
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dJointSetHingeAnchor (hinges[i], i + 0.5 - SEGMCNT/2.0, 0, 5);
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dJointSetHingeAxis (hinges[i], 0,1,0);
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dJointSetHingeParam (hinges[i],dParamFMax, 8000.0);
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// NOTE:
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// Here we tell ODE where to put the feedback on the forces for this hinge
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dJointSetFeedback (hinges[i], jfeedbacks+i);
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stress[i]=0;
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}
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for (i=0; i<STACKCNT; i++)
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{
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stackbodies[i] = dBodyCreate(world);
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dMassSetBox (&m, 2.0, 2, 2, 0.6);
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dBodySetMass(stackbodies[i],&m);
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stackgeoms[i] = dCreateBox(0, 2, 2, 0.6);
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dGeomSetBody(stackgeoms[i], stackbodies[i]);
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dBodySetPosition(stackbodies[i], 0,0,8+2*i);
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dSpaceAdd(space, stackgeoms[i]);
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}
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sliders[0] = dJointCreateSlider (world,0);
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dJointAttach(sliders[0], segbodies[0], 0);
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dJointSetSliderAxis (sliders[0], 1,0,0);
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dJointSetSliderParam (sliders[0],dParamFMax, 4000.0);
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dJointSetSliderParam (sliders[0],dParamLoStop, 0.0);
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dJointSetSliderParam (sliders[0],dParamHiStop, 0.2);
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sliders[1] = dJointCreateSlider (world,0);
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dJointAttach(sliders[1], segbodies[SEGMCNT-1], 0);
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dJointSetSliderAxis (sliders[1], 1,0,0);
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dJointSetSliderParam (sliders[1],dParamFMax, 4000.0);
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dJointSetSliderParam (sliders[1],dParamLoStop, 0.0);
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dJointSetSliderParam (sliders[1],dParamHiStop, -0.2);
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groundgeom = dCreatePlane(space, 0,0,1,0);
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for (i=0; i<SEGMCNT; i++)
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colours[i]=0.0;
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// run simulation
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dsSimulationLoop (argc,argv,352,288,&fn);
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dJointGroupEmpty (contactgroup);
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dJointGroupDestroy (contactgroup);
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// First destroy seggeoms, then space, then the world.
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for (i=0; i<SEGMCNT; i++)
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dGeomDestroy (seggeoms[i]);
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for (i=0; i<STACKCNT; i++)
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dGeomDestroy (stackgeoms[i]);
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dSpaceDestroy(space);
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dWorldDestroy (world);
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dCloseODE();
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return 0;
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}
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