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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. *
* *
*************************************************************************/
/*
This file try to demonstrate how the PR joint is working.
The axisP is draw in red and the axisR is in green
*/
#include <ode/ode.h>
#include <drawstuff/drawstuff.h>
#include <iostream>
#include <math.h>
#define DRAWSTUFF_TEXTURE_PATH "../../drawstuff/textures"
#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
// physics parameters
#define BOX1_LENGTH 2 // Size along the X axis
#define BOX1_WIDTH 1 // Size along the Y axis
#define BOX1_HEIGHT 0.4 // Size along the Z axis (up) since gravity is (0,0,-10)
#define BOX2_LENGTH 0.2
#define BOX2_WIDTH 0.1
#define BOX2_HEIGHT 0.4
#define Mass1 10
#define Mass2 0.1
#define PRISMATIC_ONLY 1
#define ROTOIDE_ONLY 2
int flag = 0;
//camera view
static float xyz[3] = {2.0f,-3.5f,2.0000f};
static float hpr[3] = {90.000f,-25.5000f,0.0000f};
//world,space,body & geom
static dWorldID world;
static dSpaceID space;
static dSpaceID box1_space;
static dSpaceID box2_space;
static dBodyID box1_body[1];
static dBodyID box2_body[1];
static dJointID joint[1];
static dJointGroupID contactgroup;
static dGeomID ground;
static dGeomID box1[1];
static dGeomID box2[1];
//collision detection
static void nearCallback (void *data, dGeomID o1, dGeomID o2)
{
int i,n;
dBodyID b1 = dGeomGetBody(o1);
dBodyID b2 = dGeomGetBody(o2);
if (b1 && b2 && dAreConnectedExcluding (b1,b2,dJointTypeContact)) return;
const int N = 10;
dContact contact[N];
n = dCollide (o1,o2,N,&contact[0].geom,sizeof(dContact));
if (n > 0)
{
for (i=0; i<n; i++)
{
contact[i].surface.mode = dContactSlip1 | dContactSlip2 |
dContactSoftERP | dContactSoftCFM | dContactApprox1;
contact[i].surface.mu = 0.1;
contact[i].surface.slip1 = 0.02;
contact[i].surface.slip2 = 0.02;
contact[i].surface.soft_erp = 0.1;
contact[i].surface.soft_cfm = 0.0001;
dJointID c = dJointCreateContact (world,contactgroup,&contact[i]);
dJointAttach (c,dGeomGetBody(contact[i].geom.g1),dGeomGetBody(contact[i].geom.g2));
}
}
}
// start simulation - set viewpoint
static void start()
{
dsSetViewpoint (xyz,hpr);
printf ("Press 'd' to add force along positive x direction.\nPress 'a' to add force along negative x direction.\n");
printf ("Press 'w' to add force along positive y direction.\nPress 's' to add force along negative y direction.\n");
printf ("Press 'e' to add torque around positive z direction.\nPress 'q' to add torque around negative z direction.\n");
printf ("Press 'o' to add force around positive x direction \n");
}
// function to update camera position at each step.
void update()
{
// const dReal *a =(dBodyGetPosition (box1_body[0]));
// float dx=a[0];
// float dy=a[1];
// float dz=a[2];
// xyz[0]=dx;
// xyz[1]=dy-5;
// xyz[2]=dz+2;
// hpr[1]=-22.5000f;
// dsSetViewpoint (xyz,hpr);
}
// called when a key pressed
static void command (int cmd)
{
switch(cmd)
{
case 'w': case 'W':
dBodyAddForce(box2_body[0],0,500,0);
std::cout<<(dBodyGetPosition(box2_body[0])[1]-dBodyGetPosition(box1_body[0])[1])<<'\n';
break;
case 's': case 'S':
dBodyAddForce(box2_body[0],0,-500,0);
std::cout<<(dBodyGetPosition(box2_body[0])[1]-dBodyGetPosition(box1_body[0])[1])<<'\n';
break;
case 'd': case 'D':
dBodyAddForce(box2_body[0],500,0,0);
std::cout<<(dBodyGetPosition(box2_body[0])[0]-dBodyGetPosition(box1_body[0])[0])<<'\n';
break;
case 'a': case 'A':
dBodyAddForce(box2_body[0],-500,0,0);
std::cout<<(dBodyGetPosition(box2_body[0])[0]-dBodyGetPosition(box1_body[0])[0])<<'\n';
break;
case 'e': case 'E':
dBodyAddRelTorque(box2_body[0],0,0,200);
break;
case 'q': case 'Q':
dBodyAddRelTorque(box2_body[0],0,0,-200);
break;
case 'o': case 'O':
dBodyAddForce(box1_body[0],10000,0,0);
break;
}
}
// simulation loop
static void simLoop (int pause)
{
if (!pause)
{
//draw 2 boxes
dVector3 ss;
dsSetTexture (DS_WOOD);
const dReal *posBox2 = dGeomGetPosition(box2[0]);
const dReal *rotBox2 = dGeomGetRotation(box2[0]);
dsSetColor (1,1,0);
dGeomBoxGetLengths (box2[0],ss);
dsDrawBox (posBox2, rotBox2, ss);
const dReal *posBox1 = dGeomGetPosition(box1[0]);
const dReal *rotBox1 = dGeomGetRotation(box1[0]);
dsSetColor (1,1,2);
dGeomBoxGetLengths (box1[0], ss);
dsDrawBox (posBox1, rotBox1, ss);
dVector3 anchorPos;
dJointGetPRAnchor (joint[0], anchorPos);
// Draw the axisP
if (ROTOIDE_ONLY != flag )
{
dsSetColor (1,0,0);
dVector3 sizeP = {0, 0.1, 0.1};
for (int i=0; i<3; ++i)
sizeP[0] += (anchorPos[i] - posBox1[i])*(anchorPos[i] - posBox1[i]);
sizeP[0] = sqrt(sizeP[0]);
dVector3 posAxisP;
for (int i=0; i<3; ++i)
posAxisP[i] = posBox1[i] + (anchorPos[i] - posBox1[i])/2.0;
dsDrawBox (posAxisP, rotBox1, sizeP);
}
// Draw the axisR
if (PRISMATIC_ONLY != flag )
{
dsSetColor (0,1,0);
dVector3 sizeR = {0, 0.1, 0.1};
for (int i=0; i<3; ++i)
sizeR[0] += (anchorPos[i] - posBox2[i])*(anchorPos[i] - posBox2[i]);
sizeR[0] = sqrt(sizeR[0]);
dVector3 posAxisR;
for (int i=0; i<3; ++i)
posAxisR[i] = posBox2[i] + (anchorPos[i] - posBox2[i])/2.0;
dsDrawBox (posAxisR, rotBox2, sizeR);
}
dSpaceCollide (space,0,&nearCallback);
dWorldQuickStep (world,0.0001);
update();
dJointGroupEmpty (contactgroup);
}
}
void Help(char **argv)
{
printf("%s ", argv[0]);
printf(" -h | --help : print this help\n");
printf(" -b | --both : Display how the complete joint works\n");
printf(" Default behavior\n");
printf(" -p | --prismatic-only : Display how the prismatic part works\n");
printf(" The anchor pts is set at the center of body 2\n");
printf(" -r | --rotoide-only : Display how the rotoide part works\n");
printf(" The anchor pts is set at the center of body 1\n");
printf(" -t | --texture-path path : Path to the texture.\n");
printf(" Default = %s\n", DRAWSTUFF_TEXTURE_PATH);
printf("--------------------------------------------------\n");
printf("Hit any key to continue:");
getchar();
exit(0);
}
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_TEXTURE_PATH;
if (argc >= 2 )
{
for (int i=1; i < argc; ++i)
{
if( 0 == strcmp("-h", argv[i]) || 0 == strcmp("--help", argv[i]) )
Help(argv);
if(!flag && (0 == strcmp("-p", argv[i]) ||0 == strcmp("--prismatic-only", argv[i])) )
flag = PRISMATIC_ONLY;
if(!flag && (0 == strcmp("-r", argv[i]) || 0 == strcmp("--rotoide-only", argv[i])) )
flag = ROTOIDE_ONLY;
if(0 == strcmp("-t", argv[i]) || 0 == strcmp("--texture-path", argv[i]))
{
int j = i+1;
if ( j+1 > argc || // Check if we have enough arguments
argv[j] == '\0' || // We should have a path here
argv[j][0] == '-' ) // We should have a path not a command line
Help(argv);
else
fn.path_to_textures = argv[++i]; // Increase i since we use this argument
}
}
}
// create world
world = dWorldCreate();
space = dHashSpaceCreate (0);
contactgroup = dJointGroupCreate (0);
dWorldSetGravity (world,0,0,-10);
ground = dCreatePlane (space,0,0,1,0);
//create two boxes
dMass m;
box1_body[0] = dBodyCreate (world);
dMassSetBox (&m,1,BOX1_LENGTH,BOX1_WIDTH,BOX1_HEIGHT);
dMassAdjust (&m,Mass1);
dBodySetMass (box1_body[0],&m);
box1[0] = dCreateBox (0,BOX1_LENGTH,BOX1_WIDTH,BOX1_HEIGHT);
dGeomSetBody (box1[0],box1_body[0]);
box2_body[0] = dBodyCreate (world);
dMassSetBox (&m,10,BOX2_LENGTH,BOX2_WIDTH,BOX2_HEIGHT);
dMassAdjust (&m,Mass2);
dBodySetMass (box2_body[0],&m);
box2[0] = dCreateBox (0,BOX2_LENGTH,BOX2_WIDTH,BOX2_HEIGHT);
dGeomSetBody (box2[0],box2_body[0]);
//set the initial positions of body1 and body2
dMatrix3 R;
dRSetIdentity(R);
dBodySetPosition (box1_body[0],0,0,BOX1_HEIGHT/2.0);
dBodySetRotation (box1_body[0], R);
dBodySetPosition (box2_body[0],
2.1,
0.0,
BOX2_HEIGHT/2.0);
dBodySetRotation (box2_body[0], R);
//set PR joint
joint[0] = dJointCreatePR(world,0);
dJointAttach (joint[0],box1_body[0],box2_body[0]);
switch (flag)
{
case PRISMATIC_ONLY:
dJointSetPRAnchor (joint[0],
2.1,
0.0,
BOX2_HEIGHT/2.0);
dJointSetPRParam (joint[0],dParamLoStop, -0.5);
dJointSetPRParam (joint[0],dParamHiStop, 1.5);
break;
case ROTOIDE_ONLY:
dJointSetPRAnchor (joint[0],
0.0,
0.0,
BOX2_HEIGHT/2.0);
dJointSetPRParam (joint[0],dParamLoStop, 0.0);
dJointSetPRParam (joint[0],dParamHiStop, 0.0);
break;
default:
dJointSetPRAnchor (joint[0],
1.1,
0.0,
BOX2_HEIGHT/2.0);
dJointSetPRParam (joint[0],dParamLoStop, -0.5);
dJointSetPRParam (joint[0],dParamHiStop, 1.5);
break;
}
dJointSetPRAxis1(joint[0],1,0,0);
dJointSetPRAxis2(joint[0],0,0,1);
// We position the 2 body
// The position of the rotoide joint is on the second body so it can rotate on itself
// and move along the X axis.
// With this anchor
// - A force in X will move only the body 2 inside the low and hi limit
// of the prismatic
// - A force in Y will make the 2 bodies to rotate around on the plane
box1_space = dSimpleSpaceCreate (space);
dSpaceSetCleanup (box1_space,0);
dSpaceAdd(box1_space,box1[0]);
// run simulation
dsSimulationLoop (argc,argv,400,300,&fn);
dJointGroupDestroy (contactgroup);
dSpaceDestroy (space);
dWorldDestroy (world);
return 0;
}
|