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GeezerVison is showing github.com — solvespace_python/src/bsp.cpp at master · sg-dev1/solvespace_python Expand file tree/ Copy pathbsp.cppMore file actions 729 lines (624 loc) · 22.6 KB / Copy pathbsp.cppFile metadata and controls729 lines (624 loc) · 22.6 KB 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 //----------------------------------------------------------------------------- // Binary space partitioning tree, used to represent a volume in 3-space // bounded by a triangle mesh. These are used to compute Boolean operations // on meshes. These aren't used for anything relating to an SShell of // ratpoly surfaces. // // Copyright 2008-2013 Jonathan Westhues. //----------------------------------------------------------------------------- #include "solvespace.h" SBsp2 *SBsp2::Alloc() { return (SBsp2 *)AllocTemporary(sizeof(SBsp2)); } SBsp3 *SBsp3::Alloc() { return (SBsp3 *)AllocTemporary(sizeof(SBsp3)); } SBsp3 *SBsp3::FromMesh(const SMesh *m) { SMesh mc = {}; for(auto const &elt : m->l) { mc.AddTriangle(&elt); } srand(0); // Let's be deterministic, at least! int n = mc.l.n; while(n > 1) { int k = rand() % n; n--; swap(mc.l[k], mc.l[n]); } SBsp3 *bsp3 = NULL; for(auto &elt : mc.l) { bsp3 = InsertOrCreate(bsp3, &elt, NULL); } mc.Clear(); return bsp3; } Vector SBsp3::IntersectionWith(Vector a, Vector b) const { double da = a.Dot(n) - d; double db = b.Dot(n) - d; ssassert(da*db < 0, "Expected segment to intersect BSP node"); double dab = (db - da); return (a.ScaledBy(db/dab)).Plus(b.ScaledBy(-da/dab)); } void SBsp3::InsertInPlane(bool pos2, STriangle *tr, SMesh *m) { Vector tc = ((tr->a).Plus(tr->b).Plus(tr->c)).ScaledBy(1.0/3); bool onFace = false; bool sameNormal = false; double maxNormalMag = -1; Vector lln, trn = tr->Normal(); SBsp3 *ll = this; while(ll) { if((ll->tri).ContainsPoint(tc)) { onFace = true; // If the mesh contains almost-zero-area triangles, and we're // just on the edge of one of those, then don't trust its normal. lln = (ll->tri).Normal(); if(lln.Magnitude() > maxNormalMag) { sameNormal = trn.Dot(lln) > 0; maxNormalMag = lln.Magnitude(); } } ll = ll->more; } if((!onFace && ((m->keepInsideOtherShell && !pos2) || (!m->keepInsideOtherShell && pos2))) || (onFace && ((m->keepCoplanar && m->flipNormal && !sameNormal) || (m->keepCoplanar && !m->flipNormal && sameNormal)))) { // We have decided that we need to keep a triangle either inside, // outside or on the other shell. So add it and flip it if requested. if(!(m->flipNormal)) { m->AddTriangle(tr->meta, tr->a, tr->b, tr->c); } else { m->AddTriangle(tr->meta, tr->c, tr->b, tr->a); } } else { m->atLeastOneDiscarded = true; } } void SBsp3::InsertHow(BspClass how, STriangle *tr, SMesh *instead) { switch(how) { case BspClass::POS: if(instead && !pos) goto alt; pos = InsertOrCreate(pos, tr, instead); break; case BspClass::NEG: if(instead && !neg) goto alt; neg = InsertOrCreate(neg, tr, instead); break; case BspClass::COPLANAR: { if(instead) goto alt; SBsp3 *m = Alloc(); m->n = n; m->d = d; m->tri = *tr; m->more = more; more = m; break; } } return; alt: if(((BspClass::POS == how) && !instead->keepInsideOtherShell) || ((BspClass::NEG == how) && instead->keepInsideOtherShell)) { // We have decided that we need to keep a triangle (either inside or // outside the other shell. So add it and flip it if requested. if(!(instead->flipNormal)) { instead->AddTriangle(tr->meta, tr->a, tr->b, tr->c); } else { instead->AddTriangle(tr->meta, tr->c, tr->b, tr->a); } } else if(how == BspClass::COPLANAR) { if(edges) { edges->InsertTriangle(tr, instead, this); } else { // I suppose this actually is allowed to happen, if the coplanar // face is the leaf, and all of its neighbors are earlier in tree? InsertInPlane(/*pos2=*/false, tr, instead); } } else { instead->atLeastOneDiscarded = true; } } class BspUtil { public: SBsp3 *bsp; size_t onc; size_t posc; size_t negc; bool *isPos; bool *isNeg; bool *isOn; // triangle operations STriangle *tr; STriangle *btri; // also as alone STriangle *ctri; // convex operations Vector *on; size_t npos; size_t nneg; Vector *vpos; // also as quad Vector *vneg; static BspUtil *Alloc() { return (BspUtil *)AllocTemporary(sizeof(BspUtil)); } void AllocOn() { on = (Vector *)AllocTemporary(sizeof(Vector) * 2); } void AllocTriangle() { btri = (STriangle *)AllocTemporary(sizeof(STriangle)); } void AllocTriangles() { btri = (STriangle *)AllocTemporary(sizeof(STriangle) * 2); ctri = &btri[1]; } void AllocQuad() { vpos = (Vector *)AllocTemporary(sizeof(Vector) * 4); } void AllocClassify(size_t size) { // Allocate a one big piece is faster than a small ones. isPos = (bool *)AllocTemporary(sizeof(bool) * size * 3); isNeg = &isPos[size]; isOn = &isNeg[size]; } void AllocVertices(size_t size) { vpos = (Vector *)AllocTemporary(sizeof(Vector) * size * 2); vneg = &vpos[size]; } void ClassifyTriangle(STriangle *tri, SBsp3 *node) { tr = tri; bsp = node; onc = 0; posc = 0; negc = 0; AllocClassify(3); double dt[3] = { (tr->a).Dot(bsp->n), (tr->b).Dot(bsp->n), (tr->c).Dot(bsp->n) }; double d = bsp->d; // Count vertices in the plane for(int i = 0; i < 3; i++) { if(dt[i] > d + LENGTH_EPS) { posc++; isPos[i] = true; } else if(dt[i] < d - LENGTH_EPS) { negc++; isNeg[i] = true; } else { onc++; isOn[i] = true; } } } bool ClassifyConvex(Vector *vertex, size_t cnt, SBsp3 *node, bool insertEdge) { bsp = node; onc = 0; posc = 0; negc = 0; AllocClassify(cnt); AllocOn(); for(size_t i = 0; i < cnt; i++) { double dt = bsp->n.Dot(vertex[i]); isPos[i] = isNeg[i] = isOn[i] = false; if(fabs(dt - bsp->d) < LENGTH_EPS) { isOn[i] = true; if(onc < 2) { on[onc] = vertex[i]; } onc++; } else if(dt > bsp->d) { isPos[i] = true; posc++; } else { isNeg[i] = true; negc++; } } if(onc != 2 && onc != 1 && onc != 0) return false; if(onc == 2) { if(insertEdge) { Vector e01 = (vertex[1]).Minus(vertex[0]); Vector e12 = (vertex[2]).Minus(vertex[1]); Vector out = e01.Cross(e12); SEdge se = SEdge::From(on[0], on[1]); bsp->edges = SBsp2::InsertOrCreateEdge(bsp->edges, &se, bsp->n, out); } } return true; } bool ClassifyConvexVertices(Vector *vertex, size_t cnt, bool insertEdges) { Vector inter[2]; int inters = 0; npos = 0; nneg = 0; // Enlarge vertices list to consider two intersections AllocVertices(cnt + 4); for(size_t i = 0; i < cnt; i++) { size_t ip = WRAP((i + 1), cnt); if(isPos[i]) { vpos[npos++] = vertex[i]; } if(isNeg[i]) { vneg[nneg++] = vertex[i]; } if(isOn[i]) { vneg[nneg++] = vertex[i]; vpos[npos++] = vertex[i]; } if((isPos[i] && isNeg[ip]) || (isNeg[i] && isPos[ip])) { Vector vi = bsp->IntersectionWith(vertex[i], vertex[ip]); vpos[npos++] = vi; vneg[nneg++] = vi; if(inters >= 2) return false; // triangulate: XXX shouldn't happen but does inter[inters++] = vi; } } ssassert(npos <= cnt + 1 && nneg <= cnt + 1, "Impossible"); if(insertEdges) { Vector e01 = (vertex[1]).Minus(vertex[0]); Vector e12 = (vertex[2]).Minus(vertex[1]); Vector out = e01.Cross(e12); if(inters == 2) { SEdge se = SEdge::From(inter[0], inter[1]); bsp->edges = SBsp2::InsertOrCreateEdge(bsp->edges, &se, bsp->n, out); } else if(inters == 1 && onc == 1) { SEdge se = SEdge::From(inter[0], on[0]); bsp->edges = SBsp2::InsertOrCreateEdge(bsp->edges, &se, bsp->n, out); } else if(inters == 0 && onc == 2) { // We already handled this on-plane existing edge } else { return false; //triangulate; } } if(nneg < 3 || npos < 3) return false; // triangulate; // XXX return true; } void ProcessEdgeInsert() { ssassert(onc == 2, "Impossible"); Vector a, b; if (!isOn[0]) { a = tr->b; b = tr->c; } else if(!isOn[1]) { a = tr->c; b = tr->a; } else if(!isOn[2]) { a = tr->a; b = tr->b; } else ssassert(false, "Impossible"); SEdge se = SEdge::From(a, b); bsp->edges = SBsp2::InsertOrCreateEdge(bsp->edges, &se, bsp->n, tr->Normal()); } bool SplitIntoTwoTriangles(bool insertEdge) { ssassert(posc == 1 && negc == 1 && onc == 1, "Impossible"); bool bpos; Vector a, b, c; // Standardize so that a is on the plane if (isOn[0]) { a = tr->a; b = tr->b; c = tr->c; bpos = isPos[1]; } else if(isOn[1]) { a = tr->b; b = tr->c; c = tr->a; bpos = isPos[2]; } else if(isOn[2]) { a = tr->c; b = tr->a; c = tr->b; bpos = isPos[0]; } else ssassert(false, "Impossible"); AllocTriangles(); Vector bPc = bsp->IntersectionWith(b, c); *btri = STriangle::From(tr->meta, a, b, bPc); *ctri = STriangle::From(tr->meta, c, a, bPc); if(insertEdge) { SEdge se = SEdge::From(a, bPc); bsp->edges = SBsp2::InsertOrCreateEdge(bsp->edges, &se, bsp->n, tr->Normal()); } return bpos; } bool SplitIntoTwoPieces(bool insertEdge) { Vector a, b, c; if(posc == 2 && negc == 1) { // Standardize so that a is on one side, and b and c are on the other. if (isNeg[0]) { a = tr->a; b = tr->b; c = tr->c; } else if(isNeg[1]) { a = tr->b; b = tr->c; c = tr->a; } else if(isNeg[2]) { a = tr->c; b = tr->a; c = tr->b; } else ssassert(false, "Impossible"); } else if(posc == 1 && negc == 2) { if (isPos[0]) { a = tr->a; b = tr->b; c = tr->c; } else if(isPos[1]) { a = tr->b; b = tr->c; c = tr->a; } else if(isPos[2]) { a = tr->c; b = tr->a; c = tr->b; } else ssassert(false, "Impossible"); } else ssassert(false, "Impossible"); Vector aPb = bsp->IntersectionWith(a, b); Vector cPa = bsp->IntersectionWith(c, a); AllocTriangle(); AllocQuad(); *btri = STriangle::From(tr->meta, a, aPb, cPa); vpos[0] = aPb; vpos[1] = b; vpos[2] = c; vpos[3] = cPa; if(insertEdge) { SEdge se = SEdge::From(aPb, cPa); bsp->edges = SBsp2::InsertOrCreateEdge(bsp->edges, &se, bsp->n, btri->Normal()); } return posc == 2 && negc == 1; } static SBsp3 *Triangulate(SBsp3 *bsp, const STriMeta &meta, Vector *vertex, size_t cnt, SMesh *instead) { for(size_t i = 0; i < cnt - 2; i++) { STriangle tr = STriangle::From(meta, vertex[0], vertex[i + 1], vertex[i + 2]); bsp = SBsp3::InsertOrCreate(bsp, &tr, instead); } return bsp; } }; void SBsp3::InsertConvexHow(BspClass how, STriMeta meta, Vector *vertex, size_t n, SMesh *instead) { switch(how) { case BspClass::POS: if(pos) { pos = pos->InsertConvex(meta, vertex, n, instead); return; } break; case BspClass::NEG: if(neg) { neg = neg->InsertConvex(meta, vertex, n, instead); return; } break; default: ssassert(false, "Unexpected BSP insert type"); } for(size_t i = 0; i < n - 2; i++) { STriangle tr = STriangle::From(meta, vertex[0], vertex[i+1], vertex[i+2]); InsertHow(how, &tr, instead); } } SBsp3 *SBsp3::InsertConvex(STriMeta meta, Vector *vertex, size_t cnt, SMesh *instead) { BspUtil *u = BspUtil::Alloc(); if(u->ClassifyConvex(vertex, cnt, this, !instead)) { if(u->posc == 0) { InsertConvexHow(BspClass::NEG, meta, vertex, cnt, instead); return this; } if(u->negc == 0) { InsertConvexHow(BspClass::POS, meta, vertex, cnt, instead); return this; } if(u->ClassifyConvexVertices(vertex, cnt, !instead)) { InsertConvexHow(BspClass::NEG, meta, u->vneg, u->nneg, instead); InsertConvexHow(BspClass::POS, meta, u->vpos, u->npos, instead); return this; } } // We don't handle the special case for this; do it as triangles return BspUtil::Triangulate(this, meta, vertex, cnt, instead); } SBsp3 *SBsp3::InsertOrCreate(SBsp3 *where, STriangle *tr, SMesh *instead) { if(where == NULL) { if(instead) { // ruevs: I do not think this code is reachable, but in // principle should we use instead->keepInsideOtherShell // in place of instead->flipNormal ? if(instead->flipNormal) { instead->atLeastOneDiscarded = true; } else { instead->AddTriangle(tr->meta, tr->a, tr->b, tr->c); } return NULL; } // Brand new node; so allocate for it, and fill us in. SBsp3 *r = Alloc(); r->n = (tr->Normal()).WithMagnitude(1); r->d = (tr->a).Dot(r->n); r->tri = *tr; return r; } where->Insert(tr, instead); return where; } void SBsp3::Insert(STriangle *tr, SMesh *instead) { BspUtil *u = BspUtil::Alloc(); u->ClassifyTriangle(tr, this); // All vertices in-plane if(u->onc == 3) { InsertHow(BspClass::COPLANAR, tr, instead); return; } // No split required if(u->posc == 0 || u->negc == 0) { if(!instead && u->onc == 2) { u->ProcessEdgeInsert(); } if(u->posc > 0) { InsertHow(BspClass::POS, tr, instead); } else { InsertHow(BspClass::NEG, tr, instead); } return; } // The polygon must be split into two triangles, one above, one below. if(u->posc == 1 && u->negc == 1 && u->onc == 1) { if(u->SplitIntoTwoTriangles(!instead)) { InsertHow(BspClass::POS, u->btri, instead); InsertHow(BspClass::NEG, u->ctri, instead); } else { InsertHow(BspClass::POS, u->ctri, instead); InsertHow(BspClass::NEG, u->btri, instead); } return; } // The polygon must be split into two pieces: a triangle and a quad. if(u->SplitIntoTwoPieces(!instead)) { InsertConvexHow(BspClass::POS, tr->meta, u->vpos, 4, instead); InsertHow(BspClass::NEG, u->btri, instead); } else { InsertConvexHow(BspClass::NEG, tr->meta, u->vpos, 4, instead); InsertHow(BspClass::POS, u->btri, instead); } } void SBsp3::GenerateInPaintOrder(SMesh *m) const { // Doesn't matter which branch we take if the normal has zero z // component, so don't need a separate case for that. if(n.z < 0) { if(pos) pos->GenerateInPaintOrder(m); } else { if(neg) neg->GenerateInPaintOrder(m); } const SBsp3 *flip = this; while(flip) { m->AddTriangle(&(flip->tri)); flip = flip->more; } if(n.z < 0) { if(neg) neg->GenerateInPaintOrder(m); } else { if(pos) pos->GenerateInPaintOrder(m); } } ///////////////////////////////// Vector SBsp2::IntersectionWith(Vector a, Vector b) const { double da = a.Dot(no) - d; double db = b.Dot(no) - d; ssassert(da*db < 0, "Expected segment to intersect BSP node"); double dab = (db - da); return (a.ScaledBy(db/dab)).Plus(b.ScaledBy(-da/dab)); } SBsp2 *SBsp2::InsertOrCreateEdge(SBsp2 *where, SEdge *nedge, Vector nnp, Vector out) { if(where == NULL) { // Brand new node; so allocate for it, and fill us in. SBsp2 *r = Alloc(); r->np = nnp; r->no = ((r->np).Cross((nedge->b).Minus(nedge->a))).WithMagnitude(1); if(out.Dot(r->no) < 0) { r->no = (r->no).ScaledBy(-1); } r->d = (nedge->a).Dot(r->no); r->edge = *nedge; return r; } where->InsertEdge(nedge, nnp, out); return where; } void SBsp2::InsertEdge(SEdge *nedge, Vector nnp, Vector out) { double dt[2] = { (nedge->a).Dot(no), (nedge->b).Dot(no) }; bool isPos[2] = {}, isNeg[2] = {}, isOn[2] = {}; for(int i = 0; i < 2; i++) { if(fabs(dt[i] - d) < LENGTH_EPS) { isOn[i] = true; } else if(dt[i] > d) { isPos[i] = true; } else { isNeg[i] = true; } } if((isPos[0] && isPos[1])||(isPos[0] && isOn[1])||(isOn[0] && isPos[1])) { pos = InsertOrCreateEdge(pos, nedge, nnp, out); return; } if((isNeg[0] && isNeg[1])||(isNeg[0] && isOn[1])||(isOn[0] && isNeg[1])) { neg = InsertOrCreateEdge(neg, nedge, nnp, out); return; } if(isOn[0] && isOn[1]) { SBsp2 *m = Alloc(); m->np = nnp; m->no = ((m->np).Cross((nedge->b).Minus(nedge->a))).WithMagnitude(1); if(out.Dot(m->no) < 0) { m->no = (m->no).ScaledBy(-1); } m->d = (nedge->a).Dot(m->no); m->edge = *nedge; m->more = more; more = m; return; } if((isPos[0] && isNeg[1]) || (isNeg[0] && isPos[1])) { Vector aPb = IntersectionWith(nedge->a, nedge->b); SEdge ea = SEdge::From(nedge->a, aPb); SEdge eb = SEdge::From(aPb, nedge->b); if(isPos[0]) { pos = InsertOrCreateEdge(pos, &ea, nnp, out); neg = InsertOrCreateEdge(neg, &eb, nnp, out); } else { neg = InsertOrCreateEdge(neg, &ea, nnp, out); pos = InsertOrCreateEdge(pos, &eb, nnp, out); } return; } ssassert(false, "Impossible"); } void SBsp2::InsertTriangleHow(BspClass how, STriangle *tr, SMesh *m, SBsp3 *bsp3) { switch(how) { case BspClass::POS: if(pos) { pos->InsertTriangle(tr, m, bsp3); } else { bsp3->InsertInPlane(/*pos2=*/true, tr, m); } break; case BspClass::NEG: if(neg) { neg->InsertTriangle(tr, m, bsp3); } else { bsp3->InsertInPlane(/*pos2=*/false, tr, m); } break; default: ssassert(false, "Unexpected BSP insert type"); } } void SBsp2::InsertTriangle(STriangle *tr, SMesh *m, SBsp3 *bsp3) { double dt[3] = { (tr->a).Dot(no), (tr->b).Dot(no), (tr->c).Dot(no) }; bool isPos[3] = {}, isNeg[3] = {}, isOn[3] = {}; int inc = 0, posc = 0, negc = 0; for(int i = 0; i < 3; i++) { if(fabs(dt[i] - d) < LENGTH_EPS) { isOn[i] = true; inc++; } else if(dt[i] > d) { isPos[i] = true; posc++; } else { isNeg[i] = true; negc++; } } if(inc == 3) { // All vertices on-line; so it's a degenerate triangle, to ignore. return; } // No split required if(posc == 0 || negc == 0) { if(posc > 0) { InsertTriangleHow(BspClass::POS, tr, m, bsp3); } else { InsertTriangleHow(BspClass::NEG, tr, m, bsp3); } return; } // The polygon must be split into two pieces, one above, one below. Vector a, b, c; if(posc == 1 && negc == 1 && inc == 1) { bool bpos; // Standardize so that a is on the plane if (isOn[0]) { a = tr->a; b = tr->b; c = tr->c; bpos = isPos[1]; } else if(isOn[1]) { a = tr->b; b = tr->c; c = tr->a; bpos = isPos[2]; } else if(isOn[2]) { a = tr->c; b = tr->a; c = tr->b; bpos = isPos[0]; } else ssassert(false, "Impossible"); Vector bPc = IntersectionWith(b, c); STriangle btri = STriangle::From(tr->meta, a, b, bPc); STriangle ctri = STriangle::From(tr->meta, c, a, bPc); if(bpos) { InsertTriangleHow(BspClass::POS, &btri, m, bsp3); InsertTriangleHow(BspClass::NEG, &ctri, m, bsp3); } else { InsertTriangleHow(BspClass::POS, &ctri, m, bsp3); InsertTriangleHow(BspClass::NEG, &btri, m, bsp3); } return; } if(posc == 2 && negc == 1) { // Standardize so that a is on one side, and b and c are on the other. if (isNeg[0]) { a = tr->a; b = tr->b; c = tr->c; } else if(isNeg[1]) { a = tr->b; b = tr->c; c = tr->a; } else if(isNeg[2]) { a = tr->c; b = tr->a; c = tr->b; } else ssassert(false, "Impossible"); } else if(posc == 1 && negc == 2) { if (isPos[0]) { a = tr->a; b = tr->b; c = tr->c; } else if(isPos[1]) { a = tr->b; b = tr->c; c = tr->a; } else if(isPos[2]) { a = tr->c; b = tr->a; c = tr->b; } else ssassert(false, "Impossible"); } else ssassert(false, "Impossible"); Vector aPb = IntersectionWith(a, b); Vector cPa = IntersectionWith(c, a); STriangle alone = STriangle::From(tr->meta, a, aPb, cPa); STriangle quad1 = STriangle::From(tr->meta, aPb, b, c ); STriangle quad2 = STriangle::From(tr->meta, aPb, c, cPa); if(posc == 2 && negc == 1) { InsertTriangleHow(BspClass::POS, &quad1, m, bsp3); InsertTriangleHow(BspClass::POS, &quad2, m, bsp3); InsertTriangleHow(BspClass::NEG, &alone, m, bsp3); } else { InsertTriangleHow(BspClass::NEG, &quad1, m, bsp3); InsertTriangleHow(BspClass::NEG, &quad2, m, bsp3); InsertTriangleHow(BspClass::POS, &alone, m, bsp3); } return; } |
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