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/*************************************************************************
* *
* Open Dynamics Engine, Copyright (C) 2001,2002 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. *
* *
*************************************************************************/
#include <ode/ode.h>
#include <drawstuff/drawstuff.h>
#ifdef _MSC_VER
#pragma warning(disable:4244 4305) // for VC++, no precision loss complaints
#endif
// select correct drawing functions
#ifdef dDOUBLE
#define dsDrawBox dsDrawBoxD
#endif
// some constants
#define SIDE (0.5f) // side length of a box
#define MASS (1.0) // mass of a box
// dynamics and collision objects
static dWorldID world;
static dBodyID body[2];
static dJointID slider;
// state set by keyboard commands
static int occasional_error = 0;
// start simulation - set viewpoint
static void start()
{
static float xyz[3] = {1.0382f,-1.0811f,1.4700f};
static float hpr[3] = {135.0000f,-19.5000f,0.0000f};
dsSetViewpoint (xyz,hpr);
printf ("Press 'e' to start/stop occasional error.\n");
}
// called when a key pressed
static void command (int cmd)
{
if (cmd == 'e' || cmd == 'E') {
occasional_error ^= 1;
}
}
// simulation loop
static void simLoop (int pause)
{
const dReal kd = -0.3; // angular damping constant
const dReal ks = 0.5; // spring constant
if (!pause) {
// add an oscillating torque to body 0, and also damp its rotational motion
static dReal a=0;
const dReal *w = dBodyGetAngularVel (body[0]);
dBodyAddTorque (body[0],kd*w[0],kd*w[1]+0.1*cos(a),kd*w[2]+0.1*sin(a));
a += 0.01;
// add a spring force to keep the bodies together, otherwise they will
// fly apart along the slider axis.
const dReal *p1 = dBodyGetPosition (body[0]);
const dReal *p2 = dBodyGetPosition (body[1]);
dBodyAddForce (body[0],ks*(p2[0]-p1[0]),ks*(p2[1]-p1[1]),
ks*(p2[2]-p1[2]));
dBodyAddForce (body[1],ks*(p1[0]-p2[0]),ks*(p1[1]-p2[1]),
ks*(p1[2]-p2[2]));
// occasionally re-orient one of the bodies to create a deliberate error.
if (occasional_error) {
static int count = 0;
if ((count % 20)==0) {
// randomly adjust orientation of body[0]
const dReal *R1;
dMatrix3 R2,R3;
R1 = dBodyGetRotation (body[0]);
dRFromAxisAndAngle (R2,dRandReal()-0.5,dRandReal()-0.5,
dRandReal()-0.5,dRandReal()-0.5);
dMultiply0 (R3,R1,R2,3,3,3);
dBodySetRotation (body[0],R3);
// randomly adjust position of body[0]
const dReal *pos = dBodyGetPosition (body[0]);
dBodySetPosition (body[0],
pos[0]+0.2*(dRandReal()-0.5),
pos[1]+0.2*(dRandReal()-0.5),
pos[2]+0.2*(dRandReal()-0.5));
}
count++;
}
dWorldStep (world,0.05);
}
dReal sides1[3] = {SIDE,SIDE,SIDE};
dReal sides2[3] = {SIDE*0.8f,SIDE*0.8f,SIDE*2.0f};
dsSetTexture (DS_WOOD);
dsSetColor (1,1,0);
dsDrawBox (dBodyGetPosition(body[0]),dBodyGetRotation(body[0]),sides1);
dsSetColor (0,1,1);
dsDrawBox (dBodyGetPosition(body[1]),dBodyGetRotation(body[1]),sides2);
}
int main (int argc, char **argv)
{
// setup pointers to drawstuff callback functions
dsFunctions fn;
fn.version = DS_VERSION;
fn.start = &start;
fn.step = &simLoop;
fn.command = &command;
fn.stop = 0;
fn.path_to_textures = "../../drawstuff/textures";
if(argc==2)
{
fn.path_to_textures = argv[1];
}
// create world
dInitODE();
world = dWorldCreate();
dMass m;
dMassSetBox (&m,1,SIDE,SIDE,SIDE);
dMassAdjust (&m,MASS);
body[0] = dBodyCreate (world);
dBodySetMass (body[0],&m);
dBodySetPosition (body[0],0,0,1);
body[1] = dBodyCreate (world);
dBodySetMass (body[1],&m);
dQuaternion q;
dQFromAxisAndAngle (q,-1,1,0,0.25*M_PI);
dBodySetPosition (body[1],0.2,0.2,1.2);
dBodySetQuaternion (body[1],q);
slider = dJointCreateSlider (world,0);
dJointAttach (slider,body[0],body[1]);
dJointSetSliderAxis (slider,1,1,1);
// run simulation
dsSimulationLoop (argc,argv,352,288,&fn);
dWorldDestroy (world);
dCloseODE();
return 0;
}
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