375 lines
13 KiB
C++
375 lines
13 KiB
C++
/*************************************************************************
|
|
* *
|
|
* 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 "objects.h"
|
|
#include "joint.h"
|
|
#include "util.h"
|
|
|
|
#define ALLOCA dALLOCA16
|
|
|
|
//****************************************************************************
|
|
// Auto disabling
|
|
|
|
void dInternalHandleAutoDisabling (dxWorld *world, dReal stepsize)
|
|
{
|
|
dxBody *bb;
|
|
for ( bb=world->firstbody; bb; bb=(dxBody*)bb->next )
|
|
{
|
|
// don't freeze objects mid-air (patch 1586738)
|
|
if ( bb->firstjoint == NULL ) continue;
|
|
|
|
// nothing to do unless this body is currently enabled and has
|
|
// the auto-disable flag set
|
|
if ( (bb->flags & (dxBodyAutoDisable|dxBodyDisabled)) != dxBodyAutoDisable ) continue;
|
|
|
|
// if sampling / threshold testing is disabled, we can never sleep.
|
|
if ( bb->adis.average_samples == 0 ) continue;
|
|
|
|
//
|
|
// see if the body is idle
|
|
//
|
|
|
|
#ifndef dNODEBUG
|
|
// sanity check
|
|
if ( bb->average_counter >= bb->adis.average_samples )
|
|
{
|
|
dUASSERT( bb->average_counter < bb->adis.average_samples, "buffer overflow" );
|
|
|
|
// something is going wrong, reset the average-calculations
|
|
bb->average_ready = 0; // not ready for average calculation
|
|
bb->average_counter = 0; // reset the buffer index
|
|
}
|
|
#endif // dNODEBUG
|
|
|
|
// sample the linear and angular velocity
|
|
bb->average_lvel_buffer[bb->average_counter][0] = bb->lvel[0];
|
|
bb->average_lvel_buffer[bb->average_counter][1] = bb->lvel[1];
|
|
bb->average_lvel_buffer[bb->average_counter][2] = bb->lvel[2];
|
|
bb->average_avel_buffer[bb->average_counter][0] = bb->avel[0];
|
|
bb->average_avel_buffer[bb->average_counter][1] = bb->avel[1];
|
|
bb->average_avel_buffer[bb->average_counter][2] = bb->avel[2];
|
|
bb->average_counter++;
|
|
|
|
// buffer ready test
|
|
if ( bb->average_counter >= bb->adis.average_samples )
|
|
{
|
|
bb->average_counter = 0; // fill the buffer from the beginning
|
|
bb->average_ready = 1; // this body is ready now for average calculation
|
|
}
|
|
|
|
int idle = 0; // Assume it's in motion unless we have samples to disprove it.
|
|
|
|
// enough samples?
|
|
if ( bb->average_ready )
|
|
{
|
|
idle = 1; // Initial assumption: IDLE
|
|
|
|
// the sample buffers are filled and ready for calculation
|
|
dVector3 average_lvel, average_avel;
|
|
|
|
// Store first velocity samples
|
|
average_lvel[0] = bb->average_lvel_buffer[0][0];
|
|
average_avel[0] = bb->average_avel_buffer[0][0];
|
|
average_lvel[1] = bb->average_lvel_buffer[0][1];
|
|
average_avel[1] = bb->average_avel_buffer[0][1];
|
|
average_lvel[2] = bb->average_lvel_buffer[0][2];
|
|
average_avel[2] = bb->average_avel_buffer[0][2];
|
|
|
|
// If we're not in "instantaneous mode"
|
|
if ( bb->adis.average_samples > 1 )
|
|
{
|
|
// add remaining velocities together
|
|
for ( unsigned int i = 1; i < bb->adis.average_samples; ++i )
|
|
{
|
|
average_lvel[0] += bb->average_lvel_buffer[i][0];
|
|
average_avel[0] += bb->average_avel_buffer[i][0];
|
|
average_lvel[1] += bb->average_lvel_buffer[i][1];
|
|
average_avel[1] += bb->average_avel_buffer[i][1];
|
|
average_lvel[2] += bb->average_lvel_buffer[i][2];
|
|
average_avel[2] += bb->average_avel_buffer[i][2];
|
|
}
|
|
|
|
// make average
|
|
dReal r1 = dReal( 1.0 ) / dReal( bb->adis.average_samples );
|
|
|
|
average_lvel[0] *= r1;
|
|
average_avel[0] *= r1;
|
|
average_lvel[1] *= r1;
|
|
average_avel[1] *= r1;
|
|
average_lvel[2] *= r1;
|
|
average_avel[2] *= r1;
|
|
}
|
|
|
|
// threshold test
|
|
dReal av_lspeed, av_aspeed;
|
|
av_lspeed = dDOT( average_lvel, average_lvel );
|
|
if ( av_lspeed > bb->adis.linear_average_threshold )
|
|
{
|
|
idle = 0; // average linear velocity is too high for idle
|
|
}
|
|
else
|
|
{
|
|
av_aspeed = dDOT( average_avel, average_avel );
|
|
if ( av_aspeed > bb->adis.angular_average_threshold )
|
|
{
|
|
idle = 0; // average angular velocity is too high for idle
|
|
}
|
|
}
|
|
}
|
|
|
|
// if it's idle, accumulate steps and time.
|
|
// these counters won't overflow because this code doesn't run for disabled bodies.
|
|
if (idle) {
|
|
bb->adis_stepsleft--;
|
|
bb->adis_timeleft -= stepsize;
|
|
}
|
|
else {
|
|
// Reset countdowns
|
|
bb->adis_stepsleft = bb->adis.idle_steps;
|
|
bb->adis_timeleft = bb->adis.idle_time;
|
|
}
|
|
|
|
// disable the body if it's idle for a long enough time
|
|
if ( bb->adis_stepsleft <= 0 && bb->adis_timeleft <= 0 )
|
|
{
|
|
bb->flags |= dxBodyDisabled; // set the disable flag
|
|
|
|
// disabling bodies should also include resetting the velocity
|
|
// should prevent jittering in big "islands"
|
|
bb->lvel[0] = 0;
|
|
bb->lvel[1] = 0;
|
|
bb->lvel[2] = 0;
|
|
bb->avel[0] = 0;
|
|
bb->avel[1] = 0;
|
|
bb->avel[2] = 0;
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
//****************************************************************************
|
|
// body rotation
|
|
|
|
// return sin(x)/x. this has a singularity at 0 so special handling is needed
|
|
// for small arguments.
|
|
|
|
static inline dReal sinc (dReal x)
|
|
{
|
|
// if |x| < 1e-4 then use a taylor series expansion. this two term expansion
|
|
// is actually accurate to one LS bit within this range if double precision
|
|
// is being used - so don't worry!
|
|
if (dFabs(x) < 1.0e-4) return REAL(1.0) - x*x*REAL(0.166666666666666666667);
|
|
else return dSin(x)/x;
|
|
}
|
|
|
|
|
|
// given a body b, apply its linear and angular rotation over the time
|
|
// interval h, thereby adjusting its position and orientation.
|
|
|
|
void dxStepBody (dxBody *b, dReal h)
|
|
{
|
|
int j;
|
|
|
|
// handle linear velocity
|
|
for (j=0; j<3; j++) b->posr.pos[j] += h * b->lvel[j];
|
|
|
|
if (b->flags & dxBodyFlagFiniteRotation) {
|
|
dVector3 irv; // infitesimal rotation vector
|
|
dQuaternion q; // quaternion for finite rotation
|
|
|
|
if (b->flags & dxBodyFlagFiniteRotationAxis) {
|
|
// split the angular velocity vector into a component along the finite
|
|
// rotation axis, and a component orthogonal to it.
|
|
dVector3 frv; // finite rotation vector
|
|
dReal k = dDOT (b->finite_rot_axis,b->avel);
|
|
frv[0] = b->finite_rot_axis[0] * k;
|
|
frv[1] = b->finite_rot_axis[1] * k;
|
|
frv[2] = b->finite_rot_axis[2] * k;
|
|
irv[0] = b->avel[0] - frv[0];
|
|
irv[1] = b->avel[1] - frv[1];
|
|
irv[2] = b->avel[2] - frv[2];
|
|
|
|
// make a rotation quaternion q that corresponds to frv * h.
|
|
// compare this with the full-finite-rotation case below.
|
|
h *= REAL(0.5);
|
|
dReal theta = k * h;
|
|
q[0] = dCos(theta);
|
|
dReal s = sinc(theta) * h;
|
|
q[1] = frv[0] * s;
|
|
q[2] = frv[1] * s;
|
|
q[3] = frv[2] * s;
|
|
}
|
|
else {
|
|
// make a rotation quaternion q that corresponds to w * h
|
|
dReal wlen = dSqrt (b->avel[0]*b->avel[0] + b->avel[1]*b->avel[1] +
|
|
b->avel[2]*b->avel[2]);
|
|
h *= REAL(0.5);
|
|
dReal theta = wlen * h;
|
|
q[0] = dCos(theta);
|
|
dReal s = sinc(theta) * h;
|
|
q[1] = b->avel[0] * s;
|
|
q[2] = b->avel[1] * s;
|
|
q[3] = b->avel[2] * s;
|
|
}
|
|
|
|
// do the finite rotation
|
|
dQuaternion q2;
|
|
dQMultiply0 (q2,q,b->q);
|
|
for (j=0; j<4; j++) b->q[j] = q2[j];
|
|
|
|
// do the infitesimal rotation if required
|
|
if (b->flags & dxBodyFlagFiniteRotationAxis) {
|
|
dReal dq[4];
|
|
dWtoDQ (irv,b->q,dq);
|
|
for (j=0; j<4; j++) b->q[j] += h * dq[j];
|
|
}
|
|
}
|
|
else {
|
|
// the normal way - do an infitesimal rotation
|
|
dReal dq[4];
|
|
dWtoDQ (b->avel,b->q,dq);
|
|
for (j=0; j<4; j++) b->q[j] += h * dq[j];
|
|
}
|
|
|
|
// normalize the quaternion and convert it to a rotation matrix
|
|
dNormalize4 (b->q);
|
|
dQtoR (b->q,b->posr.R);
|
|
|
|
// notify all attached geoms that this body has moved
|
|
for (dxGeom *geom = b->geom; geom; geom = dGeomGetBodyNext (geom))
|
|
dGeomMoved (geom);
|
|
}
|
|
|
|
//****************************************************************************
|
|
// island processing
|
|
|
|
// this groups all joints and bodies in a world into islands. all objects
|
|
// in an island are reachable by going through connected bodies and joints.
|
|
// each island can be simulated separately.
|
|
// note that joints that are not attached to anything will not be included
|
|
// in any island, an so they do not affect the simulation.
|
|
//
|
|
// this function starts new island from unvisited bodies. however, it will
|
|
// never start a new islands from a disabled body. thus islands of disabled
|
|
// bodies will not be included in the simulation. disabled bodies are
|
|
// re-enabled if they are found to be part of an active island.
|
|
|
|
void dxProcessIslands (dxWorld *world, dReal stepsize, dstepper_fn_t stepper)
|
|
{
|
|
dxBody *b,*bb,**body;
|
|
dxJoint *j,**joint;
|
|
|
|
// nothing to do if no bodies
|
|
if (world->nb <= 0) return;
|
|
|
|
// handle auto-disabling of bodies
|
|
dInternalHandleAutoDisabling (world,stepsize);
|
|
|
|
// make arrays for body and joint lists (for a single island) to go into
|
|
body = (dxBody**) ALLOCA (world->nb * sizeof(dxBody*));
|
|
joint = (dxJoint**) ALLOCA (world->nj * sizeof(dxJoint*));
|
|
int bcount = 0; // number of bodies in `body'
|
|
int jcount = 0; // number of joints in `joint'
|
|
|
|
// set all body/joint tags to 0
|
|
for (b=world->firstbody; b; b=(dxBody*)b->next) b->tag = 0;
|
|
for (j=world->firstjoint; j; j=(dxJoint*)j->next) j->tag = 0;
|
|
|
|
// allocate a stack of unvisited bodies in the island. the maximum size of
|
|
// the stack can be the lesser of the number of bodies or joints, because
|
|
// new bodies are only ever added to the stack by going through untagged
|
|
// joints. all the bodies in the stack must be tagged!
|
|
int stackalloc = (world->nj < world->nb) ? world->nj : world->nb;
|
|
dxBody **stack = (dxBody**) ALLOCA (stackalloc * sizeof(dxBody*));
|
|
|
|
for (bb=world->firstbody; bb; bb=(dxBody*)bb->next) {
|
|
// get bb = the next enabled, untagged body, and tag it
|
|
if (bb->tag || (bb->flags & dxBodyDisabled)) continue;
|
|
bb->tag = 1;
|
|
|
|
// tag all bodies and joints starting from bb.
|
|
int stacksize = 0;
|
|
b = bb;
|
|
body[0] = bb;
|
|
bcount = 1;
|
|
jcount = 0;
|
|
goto quickstart;
|
|
while (stacksize > 0) {
|
|
b = stack[--stacksize]; // pop body off stack
|
|
body[bcount++] = b; // put body on body list
|
|
quickstart:
|
|
|
|
// traverse and tag all body's joints, add untagged connected bodies
|
|
// to stack
|
|
for (dxJointNode *n=b->firstjoint; n; n=n->next) {
|
|
if (!n->joint->tag) {
|
|
n->joint->tag = 1;
|
|
joint[jcount++] = n->joint;
|
|
if (n->body && !n->body->tag) {
|
|
n->body->tag = 1;
|
|
stack[stacksize++] = n->body;
|
|
}
|
|
}
|
|
}
|
|
dIASSERT(stacksize <= world->nb);
|
|
dIASSERT(stacksize <= world->nj);
|
|
}
|
|
|
|
// now do something with body and joint lists
|
|
stepper (world,body,bcount,joint,jcount,stepsize);
|
|
|
|
// what we've just done may have altered the body/joint tag values.
|
|
// we must make sure that these tags are nonzero.
|
|
// also make sure all bodies are in the enabled state.
|
|
int i;
|
|
for (i=0; i<bcount; i++) {
|
|
body[i]->tag = 1;
|
|
body[i]->flags &= ~dxBodyDisabled;
|
|
}
|
|
for (i=0; i<jcount; i++) joint[i]->tag = 1;
|
|
}
|
|
|
|
// if debugging, check that all objects (except for disabled bodies,
|
|
// unconnected joints, and joints that are connected to disabled bodies)
|
|
// were tagged.
|
|
# ifndef dNODEBUG
|
|
for (b=world->firstbody; b; b=(dxBody*)b->next) {
|
|
if (b->flags & dxBodyDisabled) {
|
|
if (b->tag) dDebug (0,"disabled body tagged");
|
|
}
|
|
else {
|
|
if (!b->tag) dDebug (0,"enabled body not tagged");
|
|
}
|
|
}
|
|
for (j=world->firstjoint; j; j=(dxJoint*)j->next) {
|
|
if ((j->node[0].body && (j->node[0].body->flags & dxBodyDisabled)==0) ||
|
|
(j->node[1].body && (j->node[1].body->flags & dxBodyDisabled)==0)) {
|
|
if (!j->tag) dDebug (0,"attached enabled joint not tagged");
|
|
}
|
|
else {
|
|
if (j->tag) dDebug (0,"unattached or disabled joint tagged");
|
|
}
|
|
}
|
|
# endif
|
|
}
|