ode/demo/demo_step.cpp

   1 /*************************************************************************
   2  *                                                                       *
   3  * Open Dynamics Engine, Copyright (C) 2001,2002 Russell L. Smith.       *
   4  * All rights reserved.  Email: russ@q12.org   Web: www.q12.org          *
   5  *                                                                       *
   6  * This library is free software; you can redistribute it and/or         *
   7  * modify it under the terms of EITHER:                                  *
   8  *   (1) The GNU Lesser General Public License as published by the Free  *
   9  *       Software Foundation; either version 2.1 of the License, or (at  *
  10  *       your option) any later version. The text of the GNU Lesser      *
  11  *       General Public License is included with this library in the     *
  12  *       file LICENSE.TXT.                                               *
  13  *   (2) The BSD-style license that is included with this library in     *
  14  *       the file LICENSE-BSD.TXT.                                       *
  15  *                                                                       *
  16  * This library is distributed in the hope that it will be useful,       *
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the files    *
  19  * LICENSE.TXT and LICENSE-BSD.TXT for more details.                     *
  20  *                                                                       *
  21  *************************************************************************/
  22
  23 // test the step function by comparing the output of the fast and the slow
  24 // version, for various systems. currently you have to define COMPARE_METHODS
  25 // in step.cpp for this to work properly.
  26 //
  27 // @@@ report MAX error
  28
  29 #include <time.h>
  30 #include <ode/ode.h>
  31 #include <drawstuff/drawstuff.h>
  32 #include "texturepath.h"
  33
  34 #ifdef _MSC_VER
  35 #pragma warning(disable:4244 4305)  // for VC++, no precision loss complaints
  36 #endif
  37
  38 // select correct drawing functions
  39
  40 #ifdef dDOUBLE
  41 #define dsDrawBox dsDrawBoxD
  42 #define dsDrawSphere dsDrawSphereD
  43 #define dsDrawCylinder dsDrawCylinderD
  44 #define dsDrawCapsule dsDrawCapsuleD
  45 #endif
  46
  47
  48 // some constants
  49
  50 #define NUM 10                  // number of bodies
  51 #define NUMJ 9                  // number of joints
  52 #define SIDE (0.2)              // side length of a box
  53 #define MASS (1.0)              // mass of a box
  54 #define RADIUS (0.1732f)        // sphere radius
  55
  56
  57
  58 // dynamics and collision objects
  59
  60 static dWorldID world=0;
  61 static dBodyID body[NUM];
  62 static dJointID joint[NUMJ];
  63
  64
  65 // create the test system
  66
  67 void createTest()
  68 {
  69   int i,j;
  70   if (world) dWorldDestroy (world);
  71
  72   world = dWorldCreate();
  73
  74   // create random bodies
  75   for (i=0; i<NUM; i++) {
  76     // create bodies at random position and orientation
  77     body[i] = dBodyCreate (world);
  78     dBodySetPosition (body[i],dRandReal()*2-1,dRandReal()*2-1,
  79                       dRandReal()*2+RADIUS);
  80     dReal q[4];
  81     for (j=0; j<4; j++) q[j] = dRandReal()*2-1;
  82     dBodySetQuaternion (body[i],q);
  83
  84     // set random velocity
  85     dBodySetLinearVel (body[i], dRandReal()*2-1,dRandReal()*2-1,
  86                        dRandReal()*2-1);
  87     dBodySetAngularVel (body[i], dRandReal()*2-1,dRandReal()*2-1,
  88                         dRandReal()*2-1);
  89
  90     // set random mass (random diagonal mass rotated by a random amount)
  91     dMass m;
  92     dMatrix3 R;
  93     dMassSetBox (&m,1,dRandReal()+0.1,dRandReal()+0.1,dRandReal()+0.1);
  94     dMassAdjust (&m,dRandReal()+1);
  95     for (j=0; j<4; j++) q[j] = dRandReal()*2-1;
  96     dQtoR (q,R);
  97     dMassRotate (&m,R);
  98     dBodySetMass (body[i],&m);
  99   }
 100
 101   // create ball-n-socket joints at random positions, linking random bodies
 102   // (but make sure not to link the same pair of bodies twice)
 103   char linked[NUM*NUM];
 104   for (i=0; i<NUM*NUM; i++) linked[i] = 0;
 105   for (i=0; i<NUMJ; i++) {
 106     int b1,b2;
 107     do {
 108       b1 = dRandInt (NUM);
 109       b2 = dRandInt (NUM);
 110     } while (linked[b1*NUM + b2] || b1==b2);
 111     linked[b1*NUM + b2] = 1;
 112     linked[b2*NUM + b1] = 1;
 113     joint[i] = dJointCreateBall (world,0);
 114     dJointAttach (joint[i],body[b1],body[b2]);
 115     dJointSetBallAnchor (joint[i],dRandReal()*2-1,
 116                          dRandReal()*2-1,dRandReal()*2+RADIUS);
 117   }
 118
 119   for (i=0; i<NUM; i++) {
 120     // move bodies a bit to get some joint error
 121     const dReal *pos = dBodyGetPosition (body[i]);
 122     dBodySetPosition (body[i],pos[0]+dRandReal()*0.2-0.1,
 123                       pos[1]+dRandReal()*0.2-0.1,pos[2]+dRandReal()*0.2-0.1);
 124   }
 125 }
 126
 127
 128 // start simulation - set viewpoint
 129
 130 static void start()
 131 {
 132   dAllocateODEDataForThread(dAllocateMaskAll);
 133
 134   float xyz[3] = {2.6117f,-1.4433f,2.3700f};
 135   float hpr[3] = {151.5000f,-25.5000f,0.0000f};
 136   dsSetViewpoint (xyz,hpr);
 137 }
 138
 139
 140 // simulation loop
 141
 142 static void simLoop (int pause)
 143 {
 144   if (!pause) {
 145     // add random forces and torques to all bodies
 146     int i;
 147     const dReal scale1 = 5;
 148     const dReal scale2 = 5;
 149     for (i=0; i<NUM; i++) {
 150       dBodyAddForce (body[i],
 151                      scale1*(dRandReal()*2-1),
 152                      scale1*(dRandReal()*2-1),
 153                      scale1*(dRandReal()*2-1));
 154       dBodyAddTorque (body[i],
 155                      scale2*(dRandReal()*2-1),
 156                      scale2*(dRandReal()*2-1),
 157                      scale2*(dRandReal()*2-1));
 158     }
 159
 160     dWorldStep (world,0.05);
 161     createTest();
 162   }
 163
 164   // float sides[3] = {SIDE,SIDE,SIDE};
 165   dsSetColor (1,1,0);
 166   for (int i=0; i<NUM; i++)
 167     dsDrawSphere (dBodyGetPosition(body[i]), dBodyGetRotation(body[i]),RADIUS);
 168 }
 169
 170
 171 int main (int argc, char **argv)
 172 {
 173   // setup pointers to drawstuff callback functions
 174   dsFunctions fn;
 175   fn.version = DS_VERSION;
 176   fn.start = &start;
 177   fn.step = &simLoop;
 178   fn.command = 0;
 179   fn.stop = 0;
 180   fn.path_to_textures = DRAWSTUFF_TEXTURE_PATH;
 181
 182   dInitODE2(0);
 183   dRandSetSeed (time(0));
 184   createTest();
 185
 186   // run simulation
 187   dsSimulationLoop (argc, argv, DS_SIMULATION_DEFAULT_WIDTH, DS_SIMULATION_DEFAULT_HEIGHT, &fn);
 188
 189   dWorldDestroy (world);
 190   dCloseODE();
 191   return 0;
 192 }