| 1 | gezelter | 1271 | #include <math.h> | 
| 2 |  |  | #include "RigidBody.hpp" | 
| 3 |  |  | #include "VDWAtom.hpp" | 
| 4 |  |  | #include "MatVec3.h" | 
| 5 |  |  |  | 
| 6 |  |  | RigidBody::RigidBody() { | 
| 7 |  |  | is_linear = false; | 
| 8 |  |  | linear_axis =  -1; | 
| 9 |  |  | momIntTol = 1e-6; | 
| 10 |  |  | } | 
| 11 |  |  |  | 
| 12 |  |  | RigidBody::~RigidBody() { | 
| 13 |  |  | } | 
| 14 |  |  |  | 
| 15 |  |  | void RigidBody::addAtom(VDWAtom* at) { | 
| 16 |  |  |  | 
| 17 |  |  | vec3 coords; | 
| 18 |  |  |  | 
| 19 |  |  | myAtoms.push_back(at); | 
| 20 |  |  |  | 
| 21 |  |  | at->getPos(coords.vec); | 
| 22 |  |  | refCoords.push_back(coords); | 
| 23 |  |  | } | 
| 24 |  |  |  | 
| 25 |  |  | void RigidBody::getPos(double theP[3]){ | 
| 26 |  |  | for (int i = 0; i < 3 ; i++) | 
| 27 |  |  | theP[i] = pos[i]; | 
| 28 |  |  | } | 
| 29 |  |  |  | 
| 30 |  |  | void RigidBody::setPos(double theP[3]){ | 
| 31 |  |  | for (int i = 0; i < 3 ; i++) | 
| 32 |  |  | pos[i] = theP[i]; | 
| 33 |  |  | } | 
| 34 |  |  |  | 
| 35 |  |  |  | 
| 36 |  |  | void RigidBody::setEuler( double phi, double theta, double psi ){ | 
| 37 |  |  |  | 
| 38 |  |  | A[0][0] = (cos(phi) * cos(psi)) - (sin(phi) * cos(theta) * sin(psi)); | 
| 39 |  |  | A[0][1] = (sin(phi) * cos(psi)) + (cos(phi) * cos(theta) * sin(psi)); | 
| 40 |  |  | A[0][2] = sin(theta) * sin(psi); | 
| 41 |  |  |  | 
| 42 |  |  | A[1][0] = -(cos(phi) * sin(psi)) - (sin(phi) * cos(theta) * cos(psi)); | 
| 43 |  |  | A[1][1] = -(sin(phi) * sin(psi)) + (cos(phi) * cos(theta) * cos(psi)); | 
| 44 |  |  | A[1][2] = sin(theta) * cos(psi); | 
| 45 |  |  |  | 
| 46 |  |  | A[2][0] = sin(phi) * sin(theta); | 
| 47 |  |  | A[2][1] = -cos(phi) * sin(theta); | 
| 48 |  |  | A[2][2] = cos(theta); | 
| 49 |  |  |  | 
| 50 |  |  | } | 
| 51 |  |  |  | 
| 52 |  |  | void RigidBody::getQ( double q[4] ){ | 
| 53 |  |  |  | 
| 54 |  |  | double t, s; | 
| 55 |  |  | double ad1, ad2, ad3; | 
| 56 |  |  |  | 
| 57 |  |  | t = A[0][0] + A[1][1] + A[2][2] + 1.0; | 
| 58 |  |  | if( t > 0.0 ){ | 
| 59 |  |  |  | 
| 60 |  |  | s = 0.5 / sqrt( t ); | 
| 61 |  |  | q[0] = 0.25 / s; | 
| 62 |  |  | q[1] = (A[1][2] - A[2][1]) * s; | 
| 63 |  |  | q[2] = (A[2][0] - A[0][2]) * s; | 
| 64 |  |  | q[3] = (A[0][1] - A[1][0]) * s; | 
| 65 |  |  | } | 
| 66 |  |  | else{ | 
| 67 |  |  |  | 
| 68 |  |  | ad1 = fabs( A[0][0] ); | 
| 69 |  |  | ad2 = fabs( A[1][1] ); | 
| 70 |  |  | ad3 = fabs( A[2][2] ); | 
| 71 |  |  |  | 
| 72 |  |  | if( ad1 >= ad2 && ad1 >= ad3 ){ | 
| 73 |  |  |  | 
| 74 |  |  | s = 2.0 * sqrt( 1.0 + A[0][0] - A[1][1] - A[2][2] ); | 
| 75 |  |  | q[0] = (A[1][2] + A[2][1]) / s; | 
| 76 |  |  | q[1] = 0.5 / s; | 
| 77 |  |  | q[2] = (A[0][1] + A[1][0]) / s; | 
| 78 |  |  | q[3] = (A[0][2] + A[2][0]) / s; | 
| 79 |  |  | } | 
| 80 |  |  | else if( ad2 >= ad1 && ad2 >= ad3 ){ | 
| 81 |  |  |  | 
| 82 |  |  | s = sqrt( 1.0 + A[1][1] - A[0][0] - A[2][2] ) * 2.0; | 
| 83 |  |  | q[0] = (A[0][2] + A[2][0]) / s; | 
| 84 |  |  | q[1] = (A[0][1] + A[1][0]) / s; | 
| 85 |  |  | q[2] = 0.5 / s; | 
| 86 |  |  | q[3] = (A[1][2] + A[2][1]) / s; | 
| 87 |  |  | } | 
| 88 |  |  | else{ | 
| 89 |  |  |  | 
| 90 |  |  | s = sqrt( 1.0 + A[2][2] - A[0][0] - A[1][1] ) * 2.0; | 
| 91 |  |  | q[0] = (A[0][1] + A[1][0]) / s; | 
| 92 |  |  | q[1] = (A[0][2] + A[2][0]) / s; | 
| 93 |  |  | q[2] = (A[1][2] + A[2][1]) / s; | 
| 94 |  |  | q[3] = 0.5 / s; | 
| 95 |  |  | } | 
| 96 |  |  | } | 
| 97 |  |  | } | 
| 98 |  |  |  | 
| 99 |  |  | void RigidBody::setQ( double the_q[4] ){ | 
| 100 |  |  |  | 
| 101 |  |  | double q0Sqr, q1Sqr, q2Sqr, q3Sqr; | 
| 102 |  |  |  | 
| 103 |  |  | q0Sqr = the_q[0] * the_q[0]; | 
| 104 |  |  | q1Sqr = the_q[1] * the_q[1]; | 
| 105 |  |  | q2Sqr = the_q[2] * the_q[2]; | 
| 106 |  |  | q3Sqr = the_q[3] * the_q[3]; | 
| 107 |  |  |  | 
| 108 |  |  | A[0][0] = q0Sqr + q1Sqr - q2Sqr - q3Sqr; | 
| 109 |  |  | A[0][1] = 2.0 * ( the_q[1] * the_q[2] + the_q[0] * the_q[3] ); | 
| 110 |  |  | A[0][2] = 2.0 * ( the_q[1] * the_q[3] - the_q[0] * the_q[2] ); | 
| 111 |  |  |  | 
| 112 |  |  | A[1][0] = 2.0 * ( the_q[1] * the_q[2] - the_q[0] * the_q[3] ); | 
| 113 |  |  | A[1][1] = q0Sqr - q1Sqr + q2Sqr - q3Sqr; | 
| 114 |  |  | A[1][2] = 2.0 * ( the_q[2] * the_q[3] + the_q[0] * the_q[1] ); | 
| 115 |  |  |  | 
| 116 |  |  | A[2][0] = 2.0 * ( the_q[1] * the_q[3] + the_q[0] * the_q[2] ); | 
| 117 |  |  | A[2][1] = 2.0 * ( the_q[2] * the_q[3] - the_q[0] * the_q[1] ); | 
| 118 |  |  | A[2][2] = q0Sqr - q1Sqr -q2Sqr +q3Sqr; | 
| 119 |  |  |  | 
| 120 |  |  | } | 
| 121 |  |  |  | 
| 122 |  |  | void RigidBody::getA( double the_A[3][3] ){ | 
| 123 |  |  |  | 
| 124 |  |  | for (int i = 0; i < 3; i++) | 
| 125 |  |  | for (int j = 0; j < 3; j++) | 
| 126 |  |  | the_A[i][j] = A[i][j]; | 
| 127 |  |  |  | 
| 128 |  |  | } | 
| 129 |  |  |  | 
| 130 |  |  | void RigidBody::setA( double the_A[3][3] ){ | 
| 131 |  |  |  | 
| 132 |  |  | for (int i = 0; i < 3; i++) | 
| 133 |  |  | for (int j = 0; j < 3; j++) | 
| 134 |  |  | A[i][j] = the_A[i][j]; | 
| 135 |  |  |  | 
| 136 |  |  | } | 
| 137 |  |  |  | 
| 138 |  |  | void RigidBody::getI( double the_I[3][3] ){ | 
| 139 |  |  |  | 
| 140 |  |  | for (int i = 0; i < 3; i++) | 
| 141 |  |  | for (int j = 0; j < 3; j++) | 
| 142 |  |  | the_I[i][j] = I[i][j]; | 
| 143 |  |  |  | 
| 144 |  |  | } | 
| 145 |  |  |  | 
| 146 |  |  | void RigidBody::lab2Body( double r[3] ){ | 
| 147 |  |  |  | 
| 148 |  |  | double rl[3]; // the lab frame vector | 
| 149 |  |  |  | 
| 150 |  |  | rl[0] = r[0]; | 
| 151 |  |  | rl[1] = r[1]; | 
| 152 |  |  | rl[2] = r[2]; | 
| 153 |  |  |  | 
| 154 |  |  | r[0] = (A[0][0] * rl[0]) + (A[0][1] * rl[1]) + (A[0][2] * rl[2]); | 
| 155 |  |  | r[1] = (A[1][0] * rl[0]) + (A[1][1] * rl[1]) + (A[1][2] * rl[2]); | 
| 156 |  |  | r[2] = (A[2][0] * rl[0]) + (A[2][1] * rl[1]) + (A[2][2] * rl[2]); | 
| 157 |  |  |  | 
| 158 |  |  | } | 
| 159 |  |  |  | 
| 160 |  |  | void RigidBody::body2Lab( double r[3] ){ | 
| 161 |  |  |  | 
| 162 |  |  | double rb[3]; // the body frame vector | 
| 163 |  |  |  | 
| 164 |  |  | rb[0] = r[0]; | 
| 165 |  |  | rb[1] = r[1]; | 
| 166 |  |  | rb[2] = r[2]; | 
| 167 |  |  |  | 
| 168 |  |  | r[0] = (A[0][0] * rb[0]) + (A[1][0] * rb[1]) + (A[2][0] * rb[2]); | 
| 169 |  |  | r[1] = (A[0][1] * rb[0]) + (A[1][1] * rb[1]) + (A[2][1] * rb[2]); | 
| 170 |  |  | r[2] = (A[0][2] * rb[0]) + (A[1][2] * rb[1]) + (A[2][2] * rb[2]); | 
| 171 |  |  |  | 
| 172 |  |  | } | 
| 173 |  |  |  | 
| 174 |  |  | void RigidBody::calcRefCoords( ) { | 
| 175 |  |  |  | 
| 176 | chrisfen | 1279 | int i, j, it, n_linear_coords, pAxis, maxAxis, midAxis; | 
| 177 | gezelter | 1271 | double mtmp; | 
| 178 |  |  | vec3 apos; | 
| 179 |  |  | double refCOM[3]; | 
| 180 |  |  | vec3 ptmp; | 
| 181 |  |  | double Itmp[3][3]; | 
| 182 | chrisfen | 1279 | double pAxisMat[3][3], pAxisRotMat[3][3]; | 
| 183 | gezelter | 1271 | double evals[3]; | 
| 184 | chrisfen | 1279 | double prePos[3], rotPos[3]; | 
| 185 | gezelter | 1271 | double r, r2, len; | 
| 186 | chrisfen | 1279 | double iMat[3][3]; | 
| 187 | gezelter | 1271 |  | 
| 188 |  |  | // First, find the center of mass: | 
| 189 |  |  |  | 
| 190 |  |  | mass = 0.0; | 
| 191 |  |  | for (j=0; j<3; j++) | 
| 192 |  |  | refCOM[j] = 0.0; | 
| 193 |  |  |  | 
| 194 |  |  | for (i = 0; i < myAtoms.size(); i++) { | 
| 195 |  |  | mtmp = myAtoms[i]->getMass(); | 
| 196 |  |  | mass += mtmp; | 
| 197 |  |  |  | 
| 198 |  |  | apos = refCoords[i]; | 
| 199 |  |  |  | 
| 200 |  |  | for(j = 0; j < 3; j++) { | 
| 201 |  |  | refCOM[j] += apos[j]*mtmp; | 
| 202 |  |  | } | 
| 203 |  |  | } | 
| 204 |  |  |  | 
| 205 |  |  | for(j = 0; j < 3; j++) | 
| 206 |  |  | refCOM[j] /= mass; | 
| 207 |  |  |  | 
| 208 |  |  | // Next, move the origin of the reference coordinate system to the COM: | 
| 209 |  |  |  | 
| 210 |  |  | for (i = 0; i < myAtoms.size(); i++) { | 
| 211 |  |  | apos = refCoords[i]; | 
| 212 |  |  | for (j=0; j < 3; j++) { | 
| 213 |  |  | apos[j] = apos[j] - refCOM[j]; | 
| 214 |  |  | } | 
| 215 |  |  | refCoords[i] = apos; | 
| 216 |  |  | } | 
| 217 |  |  |  | 
| 218 |  |  | // Moment of Inertia calculation | 
| 219 |  |  |  | 
| 220 |  |  | for (i = 0; i < 3; i++) | 
| 221 |  |  | for (j = 0; j < 3; j++) | 
| 222 |  |  | Itmp[i][j] = 0.0; | 
| 223 |  |  |  | 
| 224 |  |  | for (it = 0; it < myAtoms.size(); it++) { | 
| 225 |  |  |  | 
| 226 |  |  | mtmp = myAtoms[it]->getMass(); | 
| 227 |  |  | ptmp = refCoords[it]; | 
| 228 |  |  | r= norm3(ptmp.vec); | 
| 229 |  |  | r2 = r*r; | 
| 230 |  |  |  | 
| 231 |  |  | for (i = 0; i < 3; i++) { | 
| 232 |  |  | for (j = 0; j < 3; j++) { | 
| 233 |  |  |  | 
| 234 |  |  | if (i==j) Itmp[i][j] += mtmp * r2; | 
| 235 |  |  |  | 
| 236 |  |  | Itmp[i][j] -= mtmp * ptmp.vec[i]*ptmp.vec[j]; | 
| 237 |  |  | } | 
| 238 |  |  | } | 
| 239 |  |  | } | 
| 240 |  |  |  | 
| 241 |  |  | diagonalize3x3(Itmp, evals, sU); | 
| 242 |  |  |  | 
| 243 |  |  | // zero out I and then fill the diagonals with the moments of inertia: | 
| 244 |  |  |  | 
| 245 |  |  | n_linear_coords = 0; | 
| 246 |  |  |  | 
| 247 |  |  | for (i = 0; i < 3; i++) { | 
| 248 |  |  | for (j = 0; j < 3; j++) { | 
| 249 |  |  | I[i][j] = 0.0; | 
| 250 |  |  | } | 
| 251 |  |  | I[i][i] = evals[i]; | 
| 252 |  |  |  | 
| 253 |  |  | if (fabs(evals[i]) < momIntTol) { | 
| 254 |  |  | is_linear = true; | 
| 255 |  |  | n_linear_coords++; | 
| 256 |  |  | linear_axis = i; | 
| 257 |  |  | } | 
| 258 |  |  | } | 
| 259 |  |  |  | 
| 260 |  |  | if (n_linear_coords > 1) { | 
| 261 |  |  | printf( | 
| 262 |  |  | "RigidBody error.\n" | 
| 263 |  |  | "\tOOPSE found more than one axis in this rigid body with a vanishing \n" | 
| 264 |  |  | "\tmoment of inertia.  This can happen in one of three ways:\n" | 
| 265 |  |  | "\t 1) Only one atom was specified, or \n" | 
| 266 |  |  | "\t 2) All atoms were specified at the same location, or\n" | 
| 267 |  |  | "\t 3) The programmers did something stupid.\n" | 
| 268 |  |  | "\tIt is silly to use a rigid body to describe this situation.  Be smarter.\n" | 
| 269 |  |  | ); | 
| 270 |  |  | exit(-1); | 
| 271 |  |  | } | 
| 272 |  |  |  | 
| 273 | chrisfen | 1279 | //sort and reorder the moment axes | 
| 274 |  |  | if (evals[0] < evals[1] && evals[0] < evals[2]) | 
| 275 |  |  | pAxis = 0; | 
| 276 |  |  | else if (evals[1] < evals[2]) | 
| 277 |  |  | pAxis = 1; | 
| 278 |  |  | else | 
| 279 |  |  | pAxis = 2; | 
| 280 |  |  |  | 
| 281 |  |  | if (evals[0] > evals[1] && evals[0] > evals[2]) | 
| 282 |  |  | maxAxis = 0; | 
| 283 |  |  | else if (evals[1] > evals[2]) | 
| 284 |  |  | maxAxis = 1; | 
| 285 |  |  | else | 
| 286 |  |  | maxAxis = 2; | 
| 287 |  |  |  | 
| 288 |  |  | midAxis = 0; | 
| 289 |  |  | if (midAxis == pAxis || midAxis == pAxis) | 
| 290 |  |  | midAxis = 1; | 
| 291 |  |  | if (midAxis == pAxis || midAxis == pAxis) | 
| 292 |  |  | midAxis = 2; | 
| 293 |  |  |  | 
| 294 |  |  | if (pAxis != maxAxis){ | 
| 295 |  |  | //zero out our matrices | 
| 296 |  |  | for (i=0; i<3; i++){ | 
| 297 |  |  | for (j=0; j<3; j++) { | 
| 298 |  |  | pAxisMat[i][j] = 0.0; | 
| 299 |  |  | pAxisRotMat[i][j] = 0.0; | 
| 300 |  |  | } | 
| 301 |  |  | } | 
| 302 |  |  |  | 
| 303 |  |  | //let z be the smallest and x be the largest eigenvalue axes | 
| 304 |  |  | for (i=0; i<3; i++){ | 
| 305 |  |  | pAxisMat[i][2] = I[i][pAxis]; | 
| 306 |  |  | pAxisMat[i][1] = I[i][midAxis]; | 
| 307 |  |  | pAxisMat[i][0] = I[i][maxAxis]; | 
| 308 |  |  | } | 
| 309 |  |  |  | 
| 310 |  |  | //calculate the proper rotation matrix | 
| 311 |  |  | transposeMat3(pAxisMat, pAxisRotMat); | 
| 312 |  |  |  | 
| 313 |  |  | //rotate the rigid body to the principle axis frame | 
| 314 |  |  | for (i = 0; i < myAtoms.size(); i++) { | 
| 315 |  |  | apos = refCoords[i]; | 
| 316 |  |  | for (j=0; j<3; j++) | 
| 317 |  |  | prePos[j] = apos[j]; | 
| 318 |  |  |  | 
| 319 |  |  | matVecMul3(pAxisRotMat, prePos, rotPos); | 
| 320 |  |  |  | 
| 321 |  |  | for (j=0; j < 3; j++) | 
| 322 |  |  | apos[j] = rotPos[j]; | 
| 323 |  |  |  | 
| 324 |  |  | refCoords[i] = apos; | 
| 325 |  |  | } | 
| 326 |  |  |  | 
| 327 |  |  | //the lab and the body frame match up at this point, so A = Identity Matrix | 
| 328 |  |  | for (i=0; i<3; i++){ | 
| 329 |  |  | for (j=0; j<3; j++){ | 
| 330 |  |  | if (i == j) | 
| 331 |  |  | iMat[i][j] = 1.0; | 
| 332 |  |  | else | 
| 333 |  |  | iMat[i][j] = 0.0; | 
| 334 |  |  | } | 
| 335 |  |  | } | 
| 336 |  |  | setA(iMat); | 
| 337 |  |  | } | 
| 338 |  |  |  | 
| 339 | gezelter | 1271 | // renormalize column vectors: | 
| 340 |  |  |  | 
| 341 |  |  | for (i=0; i < 3; i++) { | 
| 342 |  |  | len = 0.0; | 
| 343 |  |  | for (j = 0; j < 3; j++) { | 
| 344 |  |  | len += sU[i][j]*sU[i][j]; | 
| 345 |  |  | } | 
| 346 |  |  | len = sqrt(len); | 
| 347 |  |  | for (j = 0; j < 3; j++) { | 
| 348 |  |  | sU[i][j] /= len; | 
| 349 |  |  | } | 
| 350 |  |  | } | 
| 351 |  |  | } | 
| 352 |  |  |  | 
| 353 | chrisfen | 1276 | void RigidBody::doEulerToRotMat(double euler[3], double myA[3][3] ){ | 
| 354 | gezelter | 1271 |  | 
| 355 |  |  | double phi, theta, psi; | 
| 356 |  |  |  | 
| 357 |  |  | phi = euler[0]; | 
| 358 |  |  | theta = euler[1]; | 
| 359 |  |  | psi = euler[2]; | 
| 360 |  |  |  | 
| 361 |  |  | myA[0][0] = (cos(phi) * cos(psi)) - (sin(phi) * cos(theta) * sin(psi)); | 
| 362 |  |  | myA[0][1] = (sin(phi) * cos(psi)) + (cos(phi) * cos(theta) * sin(psi)); | 
| 363 |  |  | myA[0][2] = sin(theta) * sin(psi); | 
| 364 |  |  |  | 
| 365 |  |  | myA[1][0] = -(cos(phi) * sin(psi)) - (sin(phi) * cos(theta) * cos(psi)); | 
| 366 |  |  | myA[1][1] = -(sin(phi) * sin(psi)) + (cos(phi) * cos(theta) * cos(psi)); | 
| 367 |  |  | myA[1][2] = sin(theta) * cos(psi); | 
| 368 |  |  |  | 
| 369 |  |  | myA[2][0] = sin(phi) * sin(theta); | 
| 370 |  |  | myA[2][1] = -cos(phi) * sin(theta); | 
| 371 |  |  | myA[2][2] = cos(theta); | 
| 372 |  |  |  | 
| 373 |  |  | } | 
| 374 |  |  |  | 
| 375 |  |  | void RigidBody::updateAtoms() { | 
| 376 |  |  | int i, j; | 
| 377 |  |  | vec3 ref; | 
| 378 |  |  | double apos[3]; | 
| 379 |  |  |  | 
| 380 |  |  | for (i = 0; i < myAtoms.size(); i++) { | 
| 381 |  |  |  | 
| 382 |  |  | ref = refCoords[i]; | 
| 383 |  |  |  | 
| 384 |  |  | body2Lab(ref.vec); | 
| 385 |  |  |  | 
| 386 |  |  | for (j = 0; j<3; j++) | 
| 387 |  |  | apos[j] = pos[j] + ref.vec[j]; | 
| 388 |  |  |  | 
| 389 |  |  | myAtoms[i]->setPos(apos); | 
| 390 |  |  |  | 
| 391 |  |  | } | 
| 392 |  |  | } | 
| 393 |  |  |  | 
| 394 |  |  | /** | 
| 395 |  |  | * getEulerAngles computes a set of Euler angle values consistent | 
| 396 |  |  | * with an input rotation matrix.  They are returned in the following | 
| 397 |  |  | * order: | 
| 398 |  |  | *  myEuler[0] = phi; | 
| 399 |  |  | *  myEuler[1] = theta; | 
| 400 |  |  | *  myEuler[2] = psi; | 
| 401 |  |  | */ | 
| 402 |  |  | void RigidBody::getEulerAngles(double myEuler[3]) { | 
| 403 |  |  |  | 
| 404 |  |  | // We use so-called "x-convention", which is the most common | 
| 405 |  |  | // definition.  In this convention, the rotation given by Euler | 
| 406 |  |  | // angles (phi, theta, psi), where the first rotation is by an angle | 
| 407 |  |  | // phi about the z-axis, the second is by an angle theta (0 <= theta | 
| 408 |  |  | // <= 180) about the x-axis, and the third is by an angle psi about | 
| 409 |  |  | // the z-axis (again). | 
| 410 |  |  |  | 
| 411 |  |  |  | 
| 412 |  |  | double phi,theta,psi,eps; | 
| 413 | chrisfen | 1276 | double ctheta; | 
| 414 |  |  | double stheta; | 
| 415 |  |  |  | 
| 416 | gezelter | 1271 | // set the tolerance for Euler angles and rotation elements | 
| 417 |  |  |  | 
| 418 |  |  | eps = 1.0e-8; | 
| 419 |  |  |  | 
| 420 |  |  | theta = acos(min(1.0,max(-1.0,A[2][2]))); | 
| 421 |  |  | ctheta = A[2][2]; | 
| 422 |  |  | stheta = sqrt(1.0 - ctheta * ctheta); | 
| 423 |  |  |  | 
| 424 |  |  | // when sin(theta) is close to 0, we need to consider the | 
| 425 |  |  | // possibility of a singularity. In this case, we can assign an | 
| 426 |  |  | // arbitary value to phi (or psi), and then determine the psi (or | 
| 427 |  |  | // phi) or vice-versa.  We'll assume that phi always gets the | 
| 428 |  |  | // rotation, and psi is 0 in cases of singularity.  we use atan2 | 
| 429 |  |  | // instead of atan, since atan2 will give us -Pi to Pi.  Since 0 <= | 
| 430 |  |  | // theta <= 180, sin(theta) will be always non-negative. Therefore, | 
| 431 |  |  | // it never changes the sign of both of the parameters passed to | 
| 432 |  |  | // atan2. | 
| 433 |  |  |  | 
| 434 |  |  | if (fabs(stheta) <= eps){ | 
| 435 |  |  | psi = 0.0; | 
| 436 |  |  | phi = atan2(-A[1][0], A[0][0]); | 
| 437 |  |  | } | 
| 438 |  |  | // we only have one unique solution | 
| 439 |  |  | else{ | 
| 440 |  |  | phi = atan2(A[2][0], -A[2][1]); | 
| 441 |  |  | psi = atan2(A[0][2], A[1][2]); | 
| 442 |  |  | } | 
| 443 |  |  |  | 
| 444 |  |  | //wrap phi and psi, make sure they are in the range from 0 to 2*Pi | 
| 445 |  |  | //if (phi < 0) | 
| 446 |  |  | //  phi += M_PI; | 
| 447 |  |  |  | 
| 448 |  |  | //if (psi < 0) | 
| 449 |  |  | //  psi += M_PI; | 
| 450 |  |  |  | 
| 451 |  |  | myEuler[0] = phi; | 
| 452 |  |  | myEuler[1] = theta; | 
| 453 |  |  | myEuler[2] = psi; | 
| 454 |  |  |  | 
| 455 |  |  | return; | 
| 456 |  |  | } | 
| 457 |  |  |  | 
| 458 |  |  | double RigidBody::max(double x, double  y) { | 
| 459 |  |  | return (x > y) ? x : y; | 
| 460 |  |  | } | 
| 461 |  |  |  | 
| 462 |  |  | double RigidBody::min(double x, double  y) { | 
| 463 |  |  | return (x > y) ? y : x; | 
| 464 |  |  | } | 
| 465 |  |  |  | 
| 466 | chrisfen | 1276 | double RigidBody::findMaxExtent(){ | 
| 467 |  |  | int i; | 
| 468 |  |  | double refAtomPos[3]; | 
| 469 |  |  | double maxExtent; | 
| 470 |  |  | double tempExtent; | 
| 471 |  |  |  | 
| 472 |  |  | //zero the extent variables | 
| 473 |  |  | maxExtent = 0.0; | 
| 474 |  |  | tempExtent = 0.0; | 
| 475 |  |  | for (i=0; i<3; i++) | 
| 476 |  |  | refAtomPos[i] = 0.0; | 
| 477 |  |  |  | 
| 478 |  |  | //loop over all atoms | 
| 479 |  |  | for (i=0; i<myAtoms.size(); i++){ | 
| 480 |  |  | getAtomRefCoor(refAtomPos, i); | 
| 481 |  |  | tempExtent = sqrt(refAtomPos[0]*refAtomPos[0] + refAtomPos[1]*refAtomPos[1] | 
| 482 |  |  | + refAtomPos[2]*refAtomPos[2]); | 
| 483 |  |  | if (tempExtent > maxExtent) | 
| 484 |  |  | maxExtent = tempExtent; | 
| 485 |  |  | } | 
| 486 |  |  | return maxExtent; | 
| 487 |  |  | } | 
| 488 |  |  |  | 
| 489 | gezelter | 1271 | void RigidBody::findCOM() { | 
| 490 |  |  |  | 
| 491 |  |  | size_t i; | 
| 492 |  |  | int j; | 
| 493 |  |  | double mtmp; | 
| 494 |  |  | double ptmp[3]; | 
| 495 | chrisfen | 1276 |  | 
| 496 | gezelter | 1271 | for(j = 0; j < 3; j++) { | 
| 497 |  |  | pos[j] = 0.0; | 
| 498 |  |  | } | 
| 499 |  |  | mass = 0.0; | 
| 500 |  |  |  | 
| 501 |  |  | for (i = 0; i < myAtoms.size(); i++) { | 
| 502 |  |  |  | 
| 503 |  |  | mtmp = myAtoms[i]->getMass(); | 
| 504 |  |  | myAtoms[i]->getPos(ptmp); | 
| 505 |  |  |  | 
| 506 |  |  | mass += mtmp; | 
| 507 |  |  |  | 
| 508 |  |  | for(j = 0; j < 3; j++) { | 
| 509 |  |  | pos[j] += ptmp[j]*mtmp; | 
| 510 |  |  | } | 
| 511 |  |  |  | 
| 512 |  |  | } | 
| 513 |  |  |  | 
| 514 |  |  | for(j = 0; j < 3; j++) { | 
| 515 |  |  | pos[j] /= mass; | 
| 516 |  |  | } | 
| 517 |  |  |  | 
| 518 |  |  | } | 
| 519 |  |  |  | 
| 520 |  |  | void RigidBody::getAtomPos(double theP[3], int index){ | 
| 521 |  |  | vec3 ref; | 
| 522 |  |  |  | 
| 523 |  |  | if (index >= myAtoms.size()) | 
| 524 |  |  | printf( "%d is an invalid index, current rigid body contains " | 
| 525 |  |  | "%d atoms\n", index, myAtoms.size()); | 
| 526 |  |  |  | 
| 527 |  |  | ref = refCoords[index]; | 
| 528 |  |  | body2Lab(ref.vec); | 
| 529 |  |  |  | 
| 530 |  |  | theP[0] = pos[0] + ref[0]; | 
| 531 |  |  | theP[1] = pos[1] + ref[1]; | 
| 532 |  |  | theP[2] = pos[2] + ref[2]; | 
| 533 |  |  | } | 
| 534 |  |  |  | 
| 535 |  |  |  | 
| 536 |  |  | void RigidBody::getAtomRefCoor(double pos[3], int index){ | 
| 537 |  |  | vec3 ref; | 
| 538 |  |  |  | 
| 539 |  |  | ref = refCoords[index]; | 
| 540 |  |  | pos[0] = ref[0]; | 
| 541 |  |  | pos[1] = ref[1]; | 
| 542 |  |  | pos[2] = ref[2]; | 
| 543 |  |  |  | 
| 544 |  |  | } |