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author | dan miller | 2007-10-19 05:20:48 +0000 |
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committer | dan miller | 2007-10-19 05:20:48 +0000 |
commit | d48ea5bb797037069d641da41da0f195f0124491 (patch) | |
tree | 40ff433d94859d629aac933d5ec73b382f62ba1a /libraries/ode-0.9/ode/src/util.cpp | |
parent | dont ask (diff) | |
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one more for the gipper
Diffstat (limited to 'libraries/ode-0.9/ode/src/util.cpp')
-rw-r--r-- | libraries/ode-0.9/ode/src/util.cpp | 374 |
1 files changed, 374 insertions, 0 deletions
diff --git a/libraries/ode-0.9/ode/src/util.cpp b/libraries/ode-0.9/ode/src/util.cpp new file mode 100644 index 0000000..c8d6230 --- /dev/null +++ b/libraries/ode-0.9/ode/src/util.cpp | |||
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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 | #include "ode/ode.h" | ||
24 | #include "objects.h" | ||
25 | #include "joint.h" | ||
26 | #include "util.h" | ||
27 | |||
28 | #define ALLOCA dALLOCA16 | ||
29 | |||
30 | //**************************************************************************** | ||
31 | // Auto disabling | ||
32 | |||
33 | void dInternalHandleAutoDisabling (dxWorld *world, dReal stepsize) | ||
34 | { | ||
35 | dxBody *bb; | ||
36 | for ( bb=world->firstbody; bb; bb=(dxBody*)bb->next ) | ||
37 | { | ||
38 | // don't freeze objects mid-air (patch 1586738) | ||
39 | if ( bb->firstjoint == NULL ) continue; | ||
40 | |||
41 | // nothing to do unless this body is currently enabled and has | ||
42 | // the auto-disable flag set | ||
43 | if ( (bb->flags & (dxBodyAutoDisable|dxBodyDisabled)) != dxBodyAutoDisable ) continue; | ||
44 | |||
45 | // if sampling / threshold testing is disabled, we can never sleep. | ||
46 | if ( bb->adis.average_samples == 0 ) continue; | ||
47 | |||
48 | // | ||
49 | // see if the body is idle | ||
50 | // | ||
51 | |||
52 | #ifndef dNODEBUG | ||
53 | // sanity check | ||
54 | if ( bb->average_counter >= bb->adis.average_samples ) | ||
55 | { | ||
56 | dUASSERT( bb->average_counter < bb->adis.average_samples, "buffer overflow" ); | ||
57 | |||
58 | // something is going wrong, reset the average-calculations | ||
59 | bb->average_ready = 0; // not ready for average calculation | ||
60 | bb->average_counter = 0; // reset the buffer index | ||
61 | } | ||
62 | #endif // dNODEBUG | ||
63 | |||
64 | // sample the linear and angular velocity | ||
65 | bb->average_lvel_buffer[bb->average_counter][0] = bb->lvel[0]; | ||
66 | bb->average_lvel_buffer[bb->average_counter][1] = bb->lvel[1]; | ||
67 | bb->average_lvel_buffer[bb->average_counter][2] = bb->lvel[2]; | ||
68 | bb->average_avel_buffer[bb->average_counter][0] = bb->avel[0]; | ||
69 | bb->average_avel_buffer[bb->average_counter][1] = bb->avel[1]; | ||
70 | bb->average_avel_buffer[bb->average_counter][2] = bb->avel[2]; | ||
71 | bb->average_counter++; | ||
72 | |||
73 | // buffer ready test | ||
74 | if ( bb->average_counter >= bb->adis.average_samples ) | ||
75 | { | ||
76 | bb->average_counter = 0; // fill the buffer from the beginning | ||
77 | bb->average_ready = 1; // this body is ready now for average calculation | ||
78 | } | ||
79 | |||
80 | int idle = 0; // Assume it's in motion unless we have samples to disprove it. | ||
81 | |||
82 | // enough samples? | ||
83 | if ( bb->average_ready ) | ||
84 | { | ||
85 | idle = 1; // Initial assumption: IDLE | ||
86 | |||
87 | // the sample buffers are filled and ready for calculation | ||
88 | dVector3 average_lvel, average_avel; | ||
89 | |||
90 | // Store first velocity samples | ||
91 | average_lvel[0] = bb->average_lvel_buffer[0][0]; | ||
92 | average_avel[0] = bb->average_avel_buffer[0][0]; | ||
93 | average_lvel[1] = bb->average_lvel_buffer[0][1]; | ||
94 | average_avel[1] = bb->average_avel_buffer[0][1]; | ||
95 | average_lvel[2] = bb->average_lvel_buffer[0][2]; | ||
96 | average_avel[2] = bb->average_avel_buffer[0][2]; | ||
97 | |||
98 | // If we're not in "instantaneous mode" | ||
99 | if ( bb->adis.average_samples > 1 ) | ||
100 | { | ||
101 | // add remaining velocities together | ||
102 | for ( unsigned int i = 1; i < bb->adis.average_samples; ++i ) | ||
103 | { | ||
104 | average_lvel[0] += bb->average_lvel_buffer[i][0]; | ||
105 | average_avel[0] += bb->average_avel_buffer[i][0]; | ||
106 | average_lvel[1] += bb->average_lvel_buffer[i][1]; | ||
107 | average_avel[1] += bb->average_avel_buffer[i][1]; | ||
108 | average_lvel[2] += bb->average_lvel_buffer[i][2]; | ||
109 | average_avel[2] += bb->average_avel_buffer[i][2]; | ||
110 | } | ||
111 | |||
112 | // make average | ||
113 | dReal r1 = dReal( 1.0 ) / dReal( bb->adis.average_samples ); | ||
114 | |||
115 | average_lvel[0] *= r1; | ||
116 | average_avel[0] *= r1; | ||
117 | average_lvel[1] *= r1; | ||
118 | average_avel[1] *= r1; | ||
119 | average_lvel[2] *= r1; | ||
120 | average_avel[2] *= r1; | ||
121 | } | ||
122 | |||
123 | // threshold test | ||
124 | dReal av_lspeed, av_aspeed; | ||
125 | av_lspeed = dDOT( average_lvel, average_lvel ); | ||
126 | if ( av_lspeed > bb->adis.linear_average_threshold ) | ||
127 | { | ||
128 | idle = 0; // average linear velocity is too high for idle | ||
129 | } | ||
130 | else | ||
131 | { | ||
132 | av_aspeed = dDOT( average_avel, average_avel ); | ||
133 | if ( av_aspeed > bb->adis.angular_average_threshold ) | ||
134 | { | ||
135 | idle = 0; // average angular velocity is too high for idle | ||
136 | } | ||
137 | } | ||
138 | } | ||
139 | |||
140 | // if it's idle, accumulate steps and time. | ||
141 | // these counters won't overflow because this code doesn't run for disabled bodies. | ||
142 | if (idle) { | ||
143 | bb->adis_stepsleft--; | ||
144 | bb->adis_timeleft -= stepsize; | ||
145 | } | ||
146 | else { | ||
147 | // Reset countdowns | ||
148 | bb->adis_stepsleft = bb->adis.idle_steps; | ||
149 | bb->adis_timeleft = bb->adis.idle_time; | ||
150 | } | ||
151 | |||
152 | // disable the body if it's idle for a long enough time | ||
153 | if ( bb->adis_stepsleft <= 0 && bb->adis_timeleft <= 0 ) | ||
154 | { | ||
155 | bb->flags |= dxBodyDisabled; // set the disable flag | ||
156 | |||
157 | // disabling bodies should also include resetting the velocity | ||
158 | // should prevent jittering in big "islands" | ||
159 | bb->lvel[0] = 0; | ||
160 | bb->lvel[1] = 0; | ||
161 | bb->lvel[2] = 0; | ||
162 | bb->avel[0] = 0; | ||
163 | bb->avel[1] = 0; | ||
164 | bb->avel[2] = 0; | ||
165 | } | ||
166 | } | ||
167 | } | ||
168 | |||
169 | |||
170 | //**************************************************************************** | ||
171 | // body rotation | ||
172 | |||
173 | // return sin(x)/x. this has a singularity at 0 so special handling is needed | ||
174 | // for small arguments. | ||
175 | |||
176 | static inline dReal sinc (dReal x) | ||
177 | { | ||
178 | // if |x| < 1e-4 then use a taylor series expansion. this two term expansion | ||
179 | // is actually accurate to one LS bit within this range if double precision | ||
180 | // is being used - so don't worry! | ||
181 | if (dFabs(x) < 1.0e-4) return REAL(1.0) - x*x*REAL(0.166666666666666666667); | ||
182 | else return dSin(x)/x; | ||
183 | } | ||
184 | |||
185 | |||
186 | // given a body b, apply its linear and angular rotation over the time | ||
187 | // interval h, thereby adjusting its position and orientation. | ||
188 | |||
189 | void dxStepBody (dxBody *b, dReal h) | ||
190 | { | ||
191 | int j; | ||
192 | |||
193 | // handle linear velocity | ||
194 | for (j=0; j<3; j++) b->posr.pos[j] += h * b->lvel[j]; | ||
195 | |||
196 | if (b->flags & dxBodyFlagFiniteRotation) { | ||
197 | dVector3 irv; // infitesimal rotation vector | ||
198 | dQuaternion q; // quaternion for finite rotation | ||
199 | |||
200 | if (b->flags & dxBodyFlagFiniteRotationAxis) { | ||
201 | // split the angular velocity vector into a component along the finite | ||
202 | // rotation axis, and a component orthogonal to it. | ||
203 | dVector3 frv; // finite rotation vector | ||
204 | dReal k = dDOT (b->finite_rot_axis,b->avel); | ||
205 | frv[0] = b->finite_rot_axis[0] * k; | ||
206 | frv[1] = b->finite_rot_axis[1] * k; | ||
207 | frv[2] = b->finite_rot_axis[2] * k; | ||
208 | irv[0] = b->avel[0] - frv[0]; | ||
209 | irv[1] = b->avel[1] - frv[1]; | ||
210 | irv[2] = b->avel[2] - frv[2]; | ||
211 | |||
212 | // make a rotation quaternion q that corresponds to frv * h. | ||
213 | // compare this with the full-finite-rotation case below. | ||
214 | h *= REAL(0.5); | ||
215 | dReal theta = k * h; | ||
216 | q[0] = dCos(theta); | ||
217 | dReal s = sinc(theta) * h; | ||
218 | q[1] = frv[0] * s; | ||
219 | q[2] = frv[1] * s; | ||
220 | q[3] = frv[2] * s; | ||
221 | } | ||
222 | else { | ||
223 | // make a rotation quaternion q that corresponds to w * h | ||
224 | dReal wlen = dSqrt (b->avel[0]*b->avel[0] + b->avel[1]*b->avel[1] + | ||
225 | b->avel[2]*b->avel[2]); | ||
226 | h *= REAL(0.5); | ||
227 | dReal theta = wlen * h; | ||
228 | q[0] = dCos(theta); | ||
229 | dReal s = sinc(theta) * h; | ||
230 | q[1] = b->avel[0] * s; | ||
231 | q[2] = b->avel[1] * s; | ||
232 | q[3] = b->avel[2] * s; | ||
233 | } | ||
234 | |||
235 | // do the finite rotation | ||
236 | dQuaternion q2; | ||
237 | dQMultiply0 (q2,q,b->q); | ||
238 | for (j=0; j<4; j++) b->q[j] = q2[j]; | ||
239 | |||
240 | // do the infitesimal rotation if required | ||
241 | if (b->flags & dxBodyFlagFiniteRotationAxis) { | ||
242 | dReal dq[4]; | ||
243 | dWtoDQ (irv,b->q,dq); | ||
244 | for (j=0; j<4; j++) b->q[j] += h * dq[j]; | ||
245 | } | ||
246 | } | ||
247 | else { | ||
248 | // the normal way - do an infitesimal rotation | ||
249 | dReal dq[4]; | ||
250 | dWtoDQ (b->avel,b->q,dq); | ||
251 | for (j=0; j<4; j++) b->q[j] += h * dq[j]; | ||
252 | } | ||
253 | |||
254 | // normalize the quaternion and convert it to a rotation matrix | ||
255 | dNormalize4 (b->q); | ||
256 | dQtoR (b->q,b->posr.R); | ||
257 | |||
258 | // notify all attached geoms that this body has moved | ||
259 | for (dxGeom *geom = b->geom; geom; geom = dGeomGetBodyNext (geom)) | ||
260 | dGeomMoved (geom); | ||
261 | } | ||
262 | |||
263 | //**************************************************************************** | ||
264 | // island processing | ||
265 | |||
266 | // this groups all joints and bodies in a world into islands. all objects | ||
267 | // in an island are reachable by going through connected bodies and joints. | ||
268 | // each island can be simulated separately. | ||
269 | // note that joints that are not attached to anything will not be included | ||
270 | // in any island, an so they do not affect the simulation. | ||
271 | // | ||
272 | // this function starts new island from unvisited bodies. however, it will | ||
273 | // never start a new islands from a disabled body. thus islands of disabled | ||
274 | // bodies will not be included in the simulation. disabled bodies are | ||
275 | // re-enabled if they are found to be part of an active island. | ||
276 | |||
277 | void dxProcessIslands (dxWorld *world, dReal stepsize, dstepper_fn_t stepper) | ||
278 | { | ||
279 | dxBody *b,*bb,**body; | ||
280 | dxJoint *j,**joint; | ||
281 | |||
282 | // nothing to do if no bodies | ||
283 | if (world->nb <= 0) return; | ||
284 | |||
285 | // handle auto-disabling of bodies | ||
286 | dInternalHandleAutoDisabling (world,stepsize); | ||
287 | |||
288 | // make arrays for body and joint lists (for a single island) to go into | ||
289 | body = (dxBody**) ALLOCA (world->nb * sizeof(dxBody*)); | ||
290 | joint = (dxJoint**) ALLOCA (world->nj * sizeof(dxJoint*)); | ||
291 | int bcount = 0; // number of bodies in `body' | ||
292 | int jcount = 0; // number of joints in `joint' | ||
293 | |||
294 | // set all body/joint tags to 0 | ||
295 | for (b=world->firstbody; b; b=(dxBody*)b->next) b->tag = 0; | ||
296 | for (j=world->firstjoint; j; j=(dxJoint*)j->next) j->tag = 0; | ||
297 | |||
298 | // allocate a stack of unvisited bodies in the island. the maximum size of | ||
299 | // the stack can be the lesser of the number of bodies or joints, because | ||
300 | // new bodies are only ever added to the stack by going through untagged | ||
301 | // joints. all the bodies in the stack must be tagged! | ||
302 | int stackalloc = (world->nj < world->nb) ? world->nj : world->nb; | ||
303 | dxBody **stack = (dxBody**) ALLOCA (stackalloc * sizeof(dxBody*)); | ||
304 | |||
305 | for (bb=world->firstbody; bb; bb=(dxBody*)bb->next) { | ||
306 | // get bb = the next enabled, untagged body, and tag it | ||
307 | if (bb->tag || (bb->flags & dxBodyDisabled)) continue; | ||
308 | bb->tag = 1; | ||
309 | |||
310 | // tag all bodies and joints starting from bb. | ||
311 | int stacksize = 0; | ||
312 | b = bb; | ||
313 | body[0] = bb; | ||
314 | bcount = 1; | ||
315 | jcount = 0; | ||
316 | goto quickstart; | ||
317 | while (stacksize > 0) { | ||
318 | b = stack[--stacksize]; // pop body off stack | ||
319 | body[bcount++] = b; // put body on body list | ||
320 | quickstart: | ||
321 | |||
322 | // traverse and tag all body's joints, add untagged connected bodies | ||
323 | // to stack | ||
324 | for (dxJointNode *n=b->firstjoint; n; n=n->next) { | ||
325 | if (!n->joint->tag) { | ||
326 | n->joint->tag = 1; | ||
327 | joint[jcount++] = n->joint; | ||
328 | if (n->body && !n->body->tag) { | ||
329 | n->body->tag = 1; | ||
330 | stack[stacksize++] = n->body; | ||
331 | } | ||
332 | } | ||
333 | } | ||
334 | dIASSERT(stacksize <= world->nb); | ||
335 | dIASSERT(stacksize <= world->nj); | ||
336 | } | ||
337 | |||
338 | // now do something with body and joint lists | ||
339 | stepper (world,body,bcount,joint,jcount,stepsize); | ||
340 | |||
341 | // what we've just done may have altered the body/joint tag values. | ||
342 | // we must make sure that these tags are nonzero. | ||
343 | // also make sure all bodies are in the enabled state. | ||
344 | int i; | ||
345 | for (i=0; i<bcount; i++) { | ||
346 | body[i]->tag = 1; | ||
347 | body[i]->flags &= ~dxBodyDisabled; | ||
348 | } | ||
349 | for (i=0; i<jcount; i++) joint[i]->tag = 1; | ||
350 | } | ||
351 | |||
352 | // if debugging, check that all objects (except for disabled bodies, | ||
353 | // unconnected joints, and joints that are connected to disabled bodies) | ||
354 | // were tagged. | ||
355 | # ifndef dNODEBUG | ||
356 | for (b=world->firstbody; b; b=(dxBody*)b->next) { | ||
357 | if (b->flags & dxBodyDisabled) { | ||
358 | if (b->tag) dDebug (0,"disabled body tagged"); | ||
359 | } | ||
360 | else { | ||
361 | if (!b->tag) dDebug (0,"enabled body not tagged"); | ||
362 | } | ||
363 | } | ||
364 | for (j=world->firstjoint; j; j=(dxJoint*)j->next) { | ||
365 | if ((j->node[0].body && (j->node[0].body->flags & dxBodyDisabled)==0) || | ||
366 | (j->node[1].body && (j->node[1].body->flags & dxBodyDisabled)==0)) { | ||
367 | if (!j->tag) dDebug (0,"attached enabled joint not tagged"); | ||
368 | } | ||
369 | else { | ||
370 | if (j->tag) dDebug (0,"unattached or disabled joint tagged"); | ||
371 | } | ||
372 | } | ||
373 | # endif | ||
374 | } | ||