| 1 |
#include <cmath> |
| 2 |
#include "Mat3x3d.hpp" |
| 3 |
#include "Roll.hpp" |
| 4 |
#include "SimInfo.hpp" |
| 5 |
|
| 6 |
|
| 7 |
//////////////////////////////////////////////////////////////////////////////// |
| 8 |
//Implementation of DCRollAFunctor |
| 9 |
//////////////////////////////////////////////////////////////////////////////// |
| 10 |
int DCRollAFunctor::operator()(ConstraintAtom* consAtom1, ConstraintAtom* consAtom2){ |
| 11 |
Vector3d posA; |
| 12 |
Vector3d posB; |
| 13 |
Vector3d oldPosA; |
| 14 |
Vector3d oldPosB; |
| 15 |
Vector3d velA; |
| 16 |
Vector3d velB; |
| 17 |
Vector3d pab; |
| 18 |
Vector3d tempPab; |
| 19 |
Vector3d rab; |
| 20 |
Vector3d zetaA; |
| 21 |
Vector3d zetaB; |
| 22 |
Vector3d zeta; |
| 23 |
Vector3d consForce; |
| 24 |
Vector3d bondDirUnitVec; |
| 25 |
double dx, dy, dz; |
| 26 |
double rpab; |
| 27 |
double rabsq, pabsq, rpabsq; |
| 28 |
double diffsq; |
| 29 |
double gab; |
| 30 |
double dt; |
| 31 |
double pabDotZeta; |
| 32 |
double pabDotZeta2; |
| 33 |
double zeta2; |
| 34 |
double forceScalar; |
| 35 |
|
| 36 |
const int conRBMaxIter = 10; |
| 37 |
|
| 38 |
dt = info->dt; |
| 39 |
|
| 40 |
consAtom1->getOldPos(oldPosA.vec); |
| 41 |
consAtom2->getOldPos(oldPosB.vec); |
| 42 |
|
| 43 |
|
| 44 |
for(int i=0 ; i < conRBMaxIter; i++){ |
| 45 |
consAtom1->getPos(posA.vec); |
| 46 |
consAtom2->getPos(posB.vec); |
| 47 |
|
| 48 |
//discard the vector convention in alan tidesley's code |
| 49 |
//rij = rj - ri; |
| 50 |
pab = posB - posA; |
| 51 |
|
| 52 |
//periodic boundary condition |
| 53 |
|
| 54 |
info->wrapVector(pab.vec); |
| 55 |
|
| 56 |
pabsq = dotProduct(pab, pab); |
| 57 |
|
| 58 |
rabsq = curPair->getBondLength2(); |
| 59 |
diffsq = pabsq -rabsq; |
| 60 |
|
| 61 |
if (fabs(diffsq) > (consTolerance * rabsq * 2)){ |
| 62 |
rab = oldPosB - oldPosA; |
| 63 |
info->wrapVector(rab.vec); |
| 64 |
|
| 65 |
//rpab = dotProduct(rab, pab); |
| 66 |
|
| 67 |
//rpabsq = rpab * rpab; |
| 68 |
|
| 69 |
|
| 70 |
//if (rpabsq < (rabsq * -diffsq)){ |
| 71 |
// return consFail; |
| 72 |
//} |
| 73 |
|
| 74 |
bondDirUnitVec = pab; |
| 75 |
bondDirUnitVec.normalize(); |
| 76 |
|
| 77 |
calcZeta(consAtom1, bondDirUnitVec, zetaA); |
| 78 |
|
| 79 |
calcZeta(consAtom2, bondDirUnitVec, zetaB); |
| 80 |
|
| 81 |
zeta = zetaA + zetaB; |
| 82 |
zeta2 = dotProduct(zeta, zeta); |
| 83 |
|
| 84 |
pabDotZeta = dotProduct(pab, zeta); |
| 85 |
pabDotZeta2 = pabDotZeta * pabDotZeta; |
| 86 |
|
| 87 |
//solve quadratic equation |
| 88 |
//dt^4 * zeta^2 * G^2 + 2* h^2 * pab * zeta * G + pab^2 - d^2 |
| 89 |
//dt : time step |
| 90 |
// pab : |
| 91 |
//G : constraint force scalar |
| 92 |
//d: equilibrium bond length |
| 93 |
|
| 94 |
if (pabDotZeta2 - zeta2 * diffsq < 0) |
| 95 |
return consFail; |
| 96 |
|
| 97 |
//forceScalar = (pabDotZeta + sqrt(pabDotZeta2 - zeta2 * diffsq)) / dt * dt * zeta2; |
| 98 |
forceScalar = diffsq / (2 * dt * dt * pabDotZeta); |
| 99 |
// |
| 100 |
consForce = forceScalar * bondDirUnitVec; |
| 101 |
//integrate consRB1 using constraint force; |
| 102 |
integrate(consAtom1, consForce); |
| 103 |
|
| 104 |
//integrate consRB2 using constraint force; |
| 105 |
integrate(consAtom2, -consForce); |
| 106 |
|
| 107 |
} |
| 108 |
else{ |
| 109 |
if (i ==0) |
| 110 |
return consAlready; |
| 111 |
else |
| 112 |
return consSuccess; |
| 113 |
} |
| 114 |
} |
| 115 |
|
| 116 |
return consExceedMaxIter; |
| 117 |
|
| 118 |
} |
| 119 |
void DCRollAFunctor::calcZeta(ConstraintAtom* consAtom, const Vector3d& bondDir, Vector3d&zeta){ |
| 120 |
double invMass; |
| 121 |
invMass = 1.0 / consAtom ->getMass(); |
| 122 |
|
| 123 |
zeta = invMass * bondDir; |
| 124 |
} |
| 125 |
|
| 126 |
void DCRollAFunctor::integrate(ConstraintAtom* consAtom, const Vector3d& force){ |
| 127 |
StuntDouble* sd; |
| 128 |
Vector3d vel; |
| 129 |
Vector3d pos; |
| 130 |
Vector3d tempPos; |
| 131 |
Vector3d tempVel; |
| 132 |
|
| 133 |
double mass; |
| 134 |
double dtOver2; |
| 135 |
double dt; |
| 136 |
const double eConvert = 4.184e-4; |
| 137 |
|
| 138 |
dt = info->dt; |
| 139 |
dtOver2 = dt /2; |
| 140 |
sd = consAtom->getStuntDouble(); |
| 141 |
|
| 142 |
sd->getVel(vel.vec); |
| 143 |
sd->getPos(pos.vec); |
| 144 |
|
| 145 |
mass = sd->getMass(); |
| 146 |
|
| 147 |
tempVel = eConvert * dtOver2/mass * force; |
| 148 |
tempPos = dt * tempVel; |
| 149 |
|
| 150 |
vel += tempVel; |
| 151 |
pos += tempPos; |
| 152 |
|
| 153 |
sd->setVel(vel.vec); |
| 154 |
sd->setPos(pos.vec); |
| 155 |
} |
| 156 |
|
| 157 |
int DCRollAFunctor::operator()(ConstraintRigidBody* consRB1, ConstraintRigidBody* consRB2){ |
| 158 |
Vector3d posA; |
| 159 |
Vector3d posB; |
| 160 |
Vector3d oldPosA; |
| 161 |
Vector3d oldPosB; |
| 162 |
Vector3d velA; |
| 163 |
Vector3d velB; |
| 164 |
Vector3d pab; |
| 165 |
Vector3d tempPab; |
| 166 |
Vector3d rab; |
| 167 |
Vector3d zetaA; |
| 168 |
Vector3d zetaB; |
| 169 |
Vector3d zeta; |
| 170 |
Vector3d consForce; |
| 171 |
Vector3d bondDirUnitVec; |
| 172 |
double dx, dy, dz; |
| 173 |
double rpab; |
| 174 |
double rabsq, pabsq, rpabsq; |
| 175 |
double diffsq; |
| 176 |
double gab; |
| 177 |
double dt; |
| 178 |
double pabDotZeta; |
| 179 |
double pabDotZeta2; |
| 180 |
double zeta2; |
| 181 |
double forceScalar; |
| 182 |
|
| 183 |
const int conRBMaxIter = 10; |
| 184 |
|
| 185 |
dt = info->dt; |
| 186 |
|
| 187 |
consRB1->getOldAtomPos(oldPosA.vec); |
| 188 |
consRB2->getOldAtomPos(oldPosB.vec); |
| 189 |
|
| 190 |
|
| 191 |
for(int i=0 ; i < conRBMaxIter; i++){ |
| 192 |
consRB1->getCurAtomPos(posA.vec); |
| 193 |
consRB2->getCurAtomPos(posB.vec); |
| 194 |
|
| 195 |
//discard the vector convention in alan tidesley's code |
| 196 |
//rij = rj - ri; |
| 197 |
pab = posB - posA; |
| 198 |
|
| 199 |
//periodic boundary condition |
| 200 |
|
| 201 |
info->wrapVector(pab.vec); |
| 202 |
|
| 203 |
pabsq = dotProduct(pab, pab); |
| 204 |
|
| 205 |
rabsq = curPair->getBondLength2(); |
| 206 |
diffsq = pabsq -rabsq; |
| 207 |
|
| 208 |
if (fabs(diffsq) > (consTolerance * rabsq * 2)){ |
| 209 |
rab = oldPosB - oldPosA; |
| 210 |
info->wrapVector(rab.vec); |
| 211 |
|
| 212 |
//rpab = dotProduct(rab, pab); |
| 213 |
|
| 214 |
//rpabsq = rpab * rpab; |
| 215 |
|
| 216 |
|
| 217 |
//if (rpabsq < (rabsq * -diffsq)){ |
| 218 |
// return consFail; |
| 219 |
//} |
| 220 |
|
| 221 |
bondDirUnitVec = pab; |
| 222 |
bondDirUnitVec.normalize(); |
| 223 |
|
| 224 |
calcZeta(consRB1, bondDirUnitVec, zetaA); |
| 225 |
|
| 226 |
calcZeta(consRB2, bondDirUnitVec, zetaB); |
| 227 |
|
| 228 |
zeta = zetaA + zetaB; |
| 229 |
zeta2 = dotProduct(zeta, zeta); |
| 230 |
|
| 231 |
pabDotZeta = dotProduct(pab, zeta); |
| 232 |
pabDotZeta2 = pabDotZeta * pabDotZeta; |
| 233 |
|
| 234 |
//solve quadratic equation |
| 235 |
//dt^4 * zeta^2 * G^2 + 2* h^2 * pab * zeta * G + pab^2 - d^2 |
| 236 |
//dt : time step |
| 237 |
// pab : |
| 238 |
//G : constraint force scalar |
| 239 |
//d: equilibrium bond length |
| 240 |
|
| 241 |
if (pabDotZeta2 - zeta2 * diffsq < 0) |
| 242 |
return consFail; |
| 243 |
|
| 244 |
//forceScalar = (pabDotZeta + sqrt(pabDotZeta2 - zeta2 * diffsq)) / dt * dt * zeta2; |
| 245 |
forceScalar = diffsq / (2 * dt * dt * pabDotZeta); |
| 246 |
// |
| 247 |
consForce = forceScalar * bondDirUnitVec; |
| 248 |
//integrate consRB1 using constraint force; |
| 249 |
integrate(consRB1, consForce); |
| 250 |
|
| 251 |
//integrate consRB2 using constraint force; |
| 252 |
integrate(consRB2, -consForce); |
| 253 |
|
| 254 |
} |
| 255 |
else{ |
| 256 |
if (i ==0) |
| 257 |
return consAlready; |
| 258 |
else |
| 259 |
return consSuccess; |
| 260 |
} |
| 261 |
} |
| 262 |
|
| 263 |
return consExceedMaxIter; |
| 264 |
|
| 265 |
} |
| 266 |
|
| 267 |
void DCRollAFunctor::calcZeta(ConstraintRigidBody* consRB, const Vector3d& bondDir, Vector3d& zeta){ |
| 268 |
double invMass; |
| 269 |
Vector3d tempVec1; |
| 270 |
Vector3d tempVec2; |
| 271 |
Vector3d refCoor; |
| 272 |
Vector3d refCrossBond; |
| 273 |
Mat3x3d IBody; |
| 274 |
Mat3x3d IFrame; |
| 275 |
Mat3x3d invIBody; |
| 276 |
Mat3x3d invIFrame; |
| 277 |
Mat3x3d a; |
| 278 |
Mat3x3d aTrans; |
| 279 |
|
| 280 |
invMass = 1.0 / consRB ->getMass(); |
| 281 |
|
| 282 |
zeta = invMass * bondDir; |
| 283 |
|
| 284 |
consRB->getRefCoor(refCoor.vec); |
| 285 |
consRB->getA(a.element); |
| 286 |
consRB->getI(IBody.element); |
| 287 |
|
| 288 |
aTrans = a.transpose(); |
| 289 |
invIBody = IBody.inverse(); |
| 290 |
|
| 291 |
IFrame = aTrans * invIBody * a; |
| 292 |
|
| 293 |
refCrossBond = crossProduct(refCoor, bondDir); |
| 294 |
|
| 295 |
tempVec1 = invIFrame * refCrossBond; |
| 296 |
tempVec2 = crossProduct(tempVec1, refCoor); |
| 297 |
|
| 298 |
zeta += tempVec2; |
| 299 |
|
| 300 |
} |
| 301 |
|
| 302 |
void DCRollAFunctor::integrate(ConstraintRigidBody* consRB, const Vector3d& force){ |
| 303 |
StuntDouble* sd; |
| 304 |
Vector3d vel; |
| 305 |
Vector3d pos; |
| 306 |
Vector3d Tb; |
| 307 |
Vector3d ji; |
| 308 |
Vector3d tempPos; |
| 309 |
Vector3d tempVel; |
| 310 |
Vector3d tempTrq; |
| 311 |
Vector3d tempJi; |
| 312 |
double mass; |
| 313 |
double dtOver2; |
| 314 |
double dt; |
| 315 |
const double eConvert = 4.184e-4; |
| 316 |
|
| 317 |
dt = info->dt; |
| 318 |
dtOver2 = dt /2; |
| 319 |
sd = consRB->getStuntDouble(); |
| 320 |
|
| 321 |
sd->getVel(vel.vec); |
| 322 |
sd->getPos(pos.vec); |
| 323 |
|
| 324 |
mass = sd->getMass(); |
| 325 |
|
| 326 |
tempVel = eConvert * dtOver2/mass * force; |
| 327 |
tempPos = dt * tempVel; |
| 328 |
|
| 329 |
vel += tempVel; |
| 330 |
pos += tempPos; |
| 331 |
|
| 332 |
sd->setVel(vel.vec); |
| 333 |
sd->setPos(pos.vec); |
| 334 |
|
| 335 |
if (sd->isDirectional()){ |
| 336 |
|
| 337 |
// get and convert the torque to body frame |
| 338 |
|
| 339 |
sd->getTrq(Tb.vec); |
| 340 |
sd->lab2Body(Tb.vec); |
| 341 |
|
| 342 |
// get the angular momentum, and propagate a half step |
| 343 |
|
| 344 |
sd->getJ(ji.vec); |
| 345 |
|
| 346 |
ji += eConvert * dtOver2 * Tb; |
| 347 |
|
| 348 |
rotationPropagation( sd, ji.vec); |
| 349 |
|
| 350 |
sd->setJ(ji.vec); |
| 351 |
} |
| 352 |
|
| 353 |
} |
| 354 |
|
| 355 |
void DCRollAFunctor::rotationPropagation(StuntDouble* sd, double ji[3]){ |
| 356 |
double angle; |
| 357 |
double A[3][3], I[3][3]; |
| 358 |
int i, j, k; |
| 359 |
double dtOver2; |
| 360 |
|
| 361 |
dtOver2 = info->dt /2; |
| 362 |
// use the angular velocities to propagate the rotation matrix a |
| 363 |
// full time step |
| 364 |
|
| 365 |
sd->getA(A); |
| 366 |
sd->getI(I); |
| 367 |
|
| 368 |
if (sd->isLinear()) { |
| 369 |
i = sd->linearAxis(); |
| 370 |
j = (i+1)%3; |
| 371 |
k = (i+2)%3; |
| 372 |
|
| 373 |
angle = dtOver2 * ji[j] / I[j][j]; |
| 374 |
this->rotate( k, i, angle, ji, A ); |
| 375 |
|
| 376 |
angle = dtOver2 * ji[k] / I[k][k]; |
| 377 |
this->rotate( i, j, angle, ji, A); |
| 378 |
|
| 379 |
angle = dtOver2 * ji[j] / I[j][j]; |
| 380 |
this->rotate( k, i, angle, ji, A ); |
| 381 |
|
| 382 |
} else { |
| 383 |
// rotate about the x-axis |
| 384 |
angle = dtOver2 * ji[0] / I[0][0]; |
| 385 |
this->rotate( 1, 2, angle, ji, A ); |
| 386 |
|
| 387 |
// rotate about the y-axis |
| 388 |
angle = dtOver2 * ji[1] / I[1][1]; |
| 389 |
this->rotate( 2, 0, angle, ji, A ); |
| 390 |
|
| 391 |
// rotate about the z-axis |
| 392 |
angle = dtOver2 * ji[2] / I[2][2]; |
| 393 |
sd->addZangle(angle); |
| 394 |
this->rotate( 0, 1, angle, ji, A); |
| 395 |
|
| 396 |
// rotate about the y-axis |
| 397 |
angle = dtOver2 * ji[1] / I[1][1]; |
| 398 |
this->rotate( 2, 0, angle, ji, A ); |
| 399 |
|
| 400 |
// rotate about the x-axis |
| 401 |
angle = dtOver2 * ji[0] / I[0][0]; |
| 402 |
this->rotate( 1, 2, angle, ji, A ); |
| 403 |
|
| 404 |
} |
| 405 |
sd->setA( A ); |
| 406 |
} |
| 407 |
|
| 408 |
void DCRollAFunctor::rotate(int axes1, int axes2, double angle, double ji[3], double A[3][3]){ |
| 409 |
int i, j, k; |
| 410 |
double sinAngle; |
| 411 |
double cosAngle; |
| 412 |
double angleSqr; |
| 413 |
double angleSqrOver4; |
| 414 |
double top, bottom; |
| 415 |
double rot[3][3]; |
| 416 |
double tempA[3][3]; |
| 417 |
double tempJ[3]; |
| 418 |
|
| 419 |
// initialize the tempA |
| 420 |
|
| 421 |
for (i = 0; i < 3; i++){ |
| 422 |
for (j = 0; j < 3; j++){ |
| 423 |
tempA[j][i] = A[i][j]; |
| 424 |
} |
| 425 |
} |
| 426 |
|
| 427 |
// initialize the tempJ |
| 428 |
|
| 429 |
for (i = 0; i < 3; i++) |
| 430 |
tempJ[i] = ji[i]; |
| 431 |
|
| 432 |
// initalize rot as a unit matrix |
| 433 |
|
| 434 |
rot[0][0] = 1.0; |
| 435 |
rot[0][1] = 0.0; |
| 436 |
rot[0][2] = 0.0; |
| 437 |
|
| 438 |
rot[1][0] = 0.0; |
| 439 |
rot[1][1] = 1.0; |
| 440 |
rot[1][2] = 0.0; |
| 441 |
|
| 442 |
rot[2][0] = 0.0; |
| 443 |
rot[2][1] = 0.0; |
| 444 |
rot[2][2] = 1.0; |
| 445 |
|
| 446 |
// use a small angle aproximation for sin and cosine |
| 447 |
|
| 448 |
angleSqr = angle * angle; |
| 449 |
angleSqrOver4 = angleSqr / 4.0; |
| 450 |
top = 1.0 - angleSqrOver4; |
| 451 |
bottom = 1.0 + angleSqrOver4; |
| 452 |
|
| 453 |
cosAngle = top / bottom; |
| 454 |
sinAngle = angle / bottom; |
| 455 |
|
| 456 |
rot[axes1][axes1] = cosAngle; |
| 457 |
rot[axes2][axes2] = cosAngle; |
| 458 |
|
| 459 |
rot[axes1][axes2] = sinAngle; |
| 460 |
rot[axes2][axes1] = -sinAngle; |
| 461 |
|
| 462 |
// rotate the momentum acoording to: ji[] = rot[][] * ji[] |
| 463 |
|
| 464 |
for (i = 0; i < 3; i++){ |
| 465 |
ji[i] = 0.0; |
| 466 |
for (k = 0; k < 3; k++){ |
| 467 |
ji[i] += rot[i][k] * tempJ[k]; |
| 468 |
} |
| 469 |
} |
| 470 |
|
| 471 |
// rotate the Rotation matrix acording to: |
| 472 |
// A[][] = A[][] * transpose(rot[][]) |
| 473 |
|
| 474 |
|
| 475 |
// NOte for as yet unknown reason, we are performing the |
| 476 |
// calculation as: |
| 477 |
// transpose(A[][]) = transpose(A[][]) * transpose(rot[][]) |
| 478 |
|
| 479 |
for (i = 0; i < 3; i++){ |
| 480 |
for (j = 0; j < 3; j++){ |
| 481 |
A[j][i] = 0.0; |
| 482 |
for (k = 0; k < 3; k++){ |
| 483 |
A[j][i] += tempA[i][k] * rot[j][k]; |
| 484 |
} |
| 485 |
} |
| 486 |
} |
| 487 |
} |
| 488 |
//////////////////////////////////////////////////////////////////////////////// |
| 489 |
//Implementation of DCRollBFunctor |
| 490 |
//////////////////////////////////////////////////////////////////////////////// |
| 491 |
int DCRollBFunctor::operator()(ConstraintRigidBody* consRB1, ConstraintRigidBody* consRB2){ |
| 492 |
Vector3d posA; |
| 493 |
Vector3d posB; |
| 494 |
Vector3d velA; |
| 495 |
Vector3d velB; |
| 496 |
Vector3d pab; |
| 497 |
Vector3d rab; |
| 498 |
Vector3d vab; |
| 499 |
Vector3d rma; |
| 500 |
Vector3d rmb; |
| 501 |
Vector3d consForce; |
| 502 |
Vector3d bondDirUnitVec; |
| 503 |
double dx, dy, dz; |
| 504 |
double rpab; |
| 505 |
double rabsq, pabsq, rpabsq; |
| 506 |
double diffsq; |
| 507 |
double gab; |
| 508 |
double dt; |
| 509 |
double pabcDotvab; |
| 510 |
double pabDotInvMassVec; |
| 511 |
|
| 512 |
|
| 513 |
const int conRBMaxIter = 10; |
| 514 |
|
| 515 |
dt = info->dt; |
| 516 |
|
| 517 |
for(int i=0 ; i < conRBMaxIter; i++){ |
| 518 |
consRB1->getCurAtomPos(posA.vec); |
| 519 |
consRB2->getCurAtomPos(posB.vec); |
| 520 |
pab = posA - posB; |
| 521 |
|
| 522 |
consRB1->getVel(velA.vec); |
| 523 |
consRB2->getVel(velB.vec); |
| 524 |
vab = velA -velB; |
| 525 |
|
| 526 |
//periodic boundary condition |
| 527 |
|
| 528 |
info->wrapVector(pab.vec); |
| 529 |
|
| 530 |
pabsq = pab.length2(); |
| 531 |
|
| 532 |
rabsq = curPair->getBondLength2(); |
| 533 |
diffsq = rabsq - pabsq; |
| 534 |
|
| 535 |
if (fabs(diffsq) > (consTolerance * rabsq * 2)){ |
| 536 |
|
| 537 |
|
| 538 |
bondDirUnitVec = pab; |
| 539 |
bondDirUnitVec.normalize(); |
| 540 |
|
| 541 |
getEffInvMassVec(consRB1, bondDirUnitVec, rma); |
| 542 |
|
| 543 |
getEffInvMassVec(consRB2, bondDirUnitVec, rmb); |
| 544 |
|
| 545 |
pabcDotvab = dotProduct(pab, vab); |
| 546 |
pabDotInvMassVec = dotProduct(pab, rma + rmb); |
| 547 |
|
| 548 |
consForce = pabcDotvab /(2 * dt * pabDotInvMassVec) * bondDirUnitVec; |
| 549 |
//integrate consRB1 using constraint force; |
| 550 |
integrate(consRB1,consForce); |
| 551 |
|
| 552 |
//integrate consRB2 using constraint force; |
| 553 |
integrate(consRB2, -consForce); |
| 554 |
|
| 555 |
} |
| 556 |
else{ |
| 557 |
if (i ==0) |
| 558 |
return consAlready; |
| 559 |
else |
| 560 |
return consSuccess; |
| 561 |
} |
| 562 |
} |
| 563 |
|
| 564 |
return consExceedMaxIter; |
| 565 |
|
| 566 |
} |
| 567 |
|
| 568 |
void DCRollBFunctor::getEffInvMassVec(ConstraintRigidBody* consRB, const Vector3d& bondDir, Vector3d& invMassVec){ |
| 569 |
double invMass; |
| 570 |
Vector3d tempVec1; |
| 571 |
Vector3d tempVec2; |
| 572 |
Vector3d refCoor; |
| 573 |
Vector3d refCrossBond; |
| 574 |
Mat3x3d IBody; |
| 575 |
Mat3x3d IFrame; |
| 576 |
Mat3x3d invIBody; |
| 577 |
Mat3x3d invIFrame; |
| 578 |
Mat3x3d a; |
| 579 |
Mat3x3d aTrans; |
| 580 |
|
| 581 |
invMass = 1.0 / consRB ->getMass(); |
| 582 |
|
| 583 |
invMassVec = invMass * bondDir; |
| 584 |
|
| 585 |
consRB->getRefCoor(refCoor.vec); |
| 586 |
consRB->getA(a.element); |
| 587 |
consRB->getI(IBody.element); |
| 588 |
|
| 589 |
aTrans = a.transpose(); |
| 590 |
invIBody = IBody.inverse(); |
| 591 |
|
| 592 |
IFrame = aTrans * invIBody * a; |
| 593 |
|
| 594 |
refCrossBond = crossProduct(refCoor, bondDir); |
| 595 |
|
| 596 |
tempVec1 = invIFrame * refCrossBond; |
| 597 |
tempVec2 = crossProduct(tempVec1, refCoor); |
| 598 |
|
| 599 |
invMassVec += tempVec2; |
| 600 |
} |
| 601 |
|
| 602 |
void DCRollBFunctor::integrate(ConstraintRigidBody* consRB, const Vector3d& force){ |
| 603 |
const double eConvert = 4.184e-4; |
| 604 |
Vector3d vel; |
| 605 |
Vector3d pos; |
| 606 |
Vector3d Tb; |
| 607 |
Vector3d ji; |
| 608 |
double mass; |
| 609 |
double dtOver2; |
| 610 |
StuntDouble* sd; |
| 611 |
|
| 612 |
sd = consRB->getStuntDouble(); |
| 613 |
dtOver2 = info->dt/2; |
| 614 |
|
| 615 |
mass = sd->getMass(); |
| 616 |
|
| 617 |
// velocity half step |
| 618 |
|
| 619 |
vel += eConvert * dtOver2 /mass * force; |
| 620 |
|
| 621 |
sd->setVel(vel.vec); |
| 622 |
|
| 623 |
if (sd->isDirectional()){ |
| 624 |
|
| 625 |
// get and convert the torque to body frame |
| 626 |
|
| 627 |
sd->getTrq(Tb.vec); |
| 628 |
sd->lab2Body(Tb.vec); |
| 629 |
|
| 630 |
// get the angular momentum, and propagate a half step |
| 631 |
|
| 632 |
sd->getJ(ji.vec); |
| 633 |
|
| 634 |
ji += eConvert * dtOver2* Tb; |
| 635 |
|
| 636 |
sd->setJ(ji.vec); |
| 637 |
} |
| 638 |
|
| 639 |
} |
