1 // Copyright (C) 2007-2024 CEA, EDF
3 // This library is free software; you can redistribute it and/or
4 // modify it under the terms of the GNU Lesser General Public
5 // License as published by the Free Software Foundation; either
6 // version 2.1 of the License, or (at your option) any later version.
8 // This library is distributed in the hope that it will be useful,
9 // but WITHOUT ANY WARRANTY; without even the implied warranty of
10 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 // Lesser General Public License for more details.
13 // You should have received a copy of the GNU Lesser General Public
14 // License along with this library; if not, write to the Free Software
15 // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17 // See http://www.salome-platform.org/ or email : webmaster.salome@opencascade.com
20 #include "TransformedTriangle.hxx"
21 #include "VectorUtils.hxx"
22 #include "TetraAffineTransform.hxx"
32 namespace INTERP_KERNEL
36 * \brief Class representing a circular order of a set of points around their barycenter.
37 * It is used with the STL sort() algorithm to sort the point of the two polygons
40 class ProjectedCentralCircularSortOrder
44 /// Enumeration of different planes to project on when calculating order
45 enum CoordType { XY, XZ, YZ };
50 * @param barycenter double[3] containing the barycenter of the points to be compared
51 * @param type plane to project on when comparing. The comparison will not work if all the points are in a plane perpendicular
52 * to the plane being projected on
54 ProjectedCentralCircularSortOrder(const double* barycenter, const CoordType type)
55 : _aIdx((type == YZ) ? 1 : 0),
56 _bIdx((type == XY) ? 1 : 2),
57 _a(barycenter[_aIdx]),
63 * Comparison operator.
64 * Compares the relative position between two points in their ordering around the barycenter.
66 * @param pt1 a double[3] representing a point
67 * @param pt2 a double[3] representing a point
68 * @return true if the angle of the difference vector between pt1 and the barycenter is greater than that
69 * of the difference vector between pt2 and the barycenter.
71 bool operator()(const double* pt1, const double* pt2)
73 // calculate angles with the axis
74 const double ang1 = atan2(pt1[_aIdx] - _a, pt1[_bIdx] - _b);
75 const double ang2 = atan2(pt2[_aIdx] - _a, pt2[_bIdx] - _b);
81 /// index corresponding to first coordinate of plane on which points are projected
84 /// index corresponding to second coordinate of plane on which points are projected
87 /// value of first projected coordinate of the barycenter
90 /// value of second projected coordinate of the barycenter
94 // ----------------------------------------------------------------------------------
95 // TransformedTriangle PUBLIC
96 // ----------------------------------------------------------------------------------
101 * The coordinates are copied to the internal member variables
103 * @param p array of three doubles containing coordinates of P
104 * @param q array of three doubles containing coordinates of Q
105 * @param r array of three doubles containing coordinates of R
107 TransformedTriangle::TransformedTriangle(double* p, double* q, double* r)
108 : _is_double_products_calculated(false), _is_triple_products_calculated(false), _volume(0)
111 for(int i = 0 ; i < 3 ; ++i)
114 _coords[5*P + i] = p[i];
115 _coords[5*Q + i] = q[i];
116 _coords[5*R + i] = r[i];
121 _coords[5*P + 3] = 1 - p[0] - p[1] - p[2];
122 _coords[5*Q + 3] = 1 - q[0] - q[1] - q[2];
123 _coords[5*R + 3] = 1 - r[0] - r[1] - r[2];
126 _coords[5*P + 4] = 1 - p[0] - p[1];
127 _coords[5*Q + 4] = 1 - q[0] - q[1];
128 _coords[5*R + 4] = 1 - r[0] - r[1];
130 resetNearZeroCoordinates();
132 // initialise rest of data
133 preCalculateDoubleProducts();
135 preCalculateTriangleSurroundsEdge();
137 preCalculateTripleProducts();
144 * Deallocates the memory used to store the points of the polygons.
145 * This memory is allocated in calculateIntersectionAndProjectionPolygons().
147 TransformedTriangle::~TransformedTriangle()
149 // delete elements of polygons
150 for(auto& it: _polygonA)
152 for(auto& it: _polygonB)
157 * Calculates the volume of intersection between the triangle and the
160 * @return volume of intersection of this triangle with unit tetrahedron,
161 * as described in Grandy
164 double TransformedTriangle::calculateIntersectionVolume()
166 // check first that we are not below z - plane
167 if(isTriangleBelowTetraeder())
169 LOG(2, " --- Triangle is below tetraeder - V = 0.0");
173 // get the sign of the volume - equal to the sign of the z-component of the normal
174 // of the triangle, u_x * v_y - u_y * v_x, where u = q - p and v = r - p
175 // if it is zero, the triangle is perpendicular to the z - plane and so the volume is zero
176 // const double uv_xy[4] =
178 // _coords[5*Q] - _coords[5*P], _coords[5*Q + 1] - _coords[5*P + 1], // u_x, u_y
179 // _coords[5*R] - _coords[5*P], _coords[5*R + 1] - _coords[5*P + 1] // v_x, v_y
182 // double sign = uv_xy[0] * uv_xy[3] - uv_xy[1] * uv_xy[2];
183 int sign = isTriangleInclinedToFacet( OXY );
187 LOG(2, " --- Triangle is perpendicular to z-plane - V = 0.0");
188 return _volume = 0.0;
193 //sign = sign > 0.0 ? 1.0 : -1.0;
195 LOG(2, "-- Calculating intersection polygons ... ");
196 calculateIntersectionAndProjectionPolygons();
198 double barycenter[3];
200 // calculate volume under A
202 if(_polygonA.size() > 2)
204 LOG(2, "---- Treating polygon A ... ");
206 LOG(3, " --- Final points in polygon A");
207 for(const auto& pt: _polygonA)
210 calculatePolygonBarycenter(A, barycenter);
211 sortIntersectionPolygon(A, barycenter);
212 volA = calculateVolumeUnderPolygon(A, barycenter);
213 LOG(2, "Volume is " << sign * volA);
217 // if triangle is not in h = 0 plane, calculate volume under B
218 if(_polygonB.size() > 2 && !isTriangleInPlaneOfFacet(XYZ)) // second condition avoids double counting in case triangle fully included in h=0 facet
220 LOG(2, "---- Treating polygon B ... ");
222 LOG(3, " --- Final points in polygon B");
223 for(const auto& pt: _polygonB)
226 calculatePolygonBarycenter(B, barycenter);
227 sortIntersectionPolygon(B, barycenter);
228 volB = calculateVolumeUnderPolygon(B, barycenter);
229 LOG(2, "Volume is " << sign * volB);
233 LOG(2, "############ Triangle :")
235 LOG(2, "vol A = " << volA);
236 LOG(2, "vol B = " << volB);
237 LOG(2, "TOTAL = " << sign*(volA+volB));
240 return _volume = sign * (volA + volB);
245 * Calculates the volume of intersection between the triangle and the
248 * @return volume of intersection of this triangle with unit tetrahedron,
249 * as described in Grandy
252 double TransformedTriangle::calculateIntersectionSurface(TetraAffineTransform* tat)
254 // check first that we are not below z - plane
255 if(isTriangleBelowTetraeder())
257 LOG(2, " --- Triangle is below tetraeder - V = 0.0");
261 LOG(2, "-- Calculating intersection polygon ... ");
262 calculateIntersectionPolygon();
265 if(_polygonA.size() > 2) {
266 double barycenter[3];
267 calculatePolygonBarycenter(A, barycenter);
268 sortIntersectionPolygon(A, barycenter);
269 const std::size_t nbPoints = _polygonA.size();
270 for(std::size_t i = 0 ; i < nbPoints ; ++i)
271 tat->reverseApply(_polygonA[i], _polygonA[i]);
272 _volume = calculateSurfacePolygon();
278 // ----------------------------------------------------------------------------------
279 // TransformedTriangle PROTECTED
280 // ----------------------------------------------------------------------------------
283 * Calculates the intersection polygons A and B, performing the intersection tests
284 * and storing the corresponding points in the vectors _polygonA and _polygonB.
286 * @post _polygonA contains the intersection polygon A and _polygonB contains the
287 * intersection polygon B.
290 void TransformedTriangle::calculateIntersectionAndProjectionPolygons()
293 std::cout << " @@@@@@@@ COORDS @@@@@@ " << std::endl;
297 assert(_polygonA.size() == 0);
298 assert(_polygonB.size() == 0);
299 // avoid reallocations in push_back() by pre-allocating enough memory
300 // we should never have more than 20 points
301 _polygonA.reserve(20);
302 _polygonB.reserve(20);
303 // -- surface intersections
305 for(TetraEdge edge = OX ; edge <= ZX ; edge = TetraEdge(edge + 1))
307 if(testSurfaceEdgeIntersection(edge))
309 double* ptA = new double[3];
310 calcIntersectionPtSurfaceEdge(edge, ptA);
311 _polygonA.push_back(ptA);
312 LOG(3,"Surface-edge (edge " << strTE(edge) << "): " << vToStr(ptA) << " added to A ");
315 double* ptB = new double[3];
316 copyVector3(ptA, ptB);
317 _polygonB.push_back(ptB);
318 LOG(3,"Surface-edge (edge " << strTE(edge) << "): " << vToStr(ptB) << " added to B ");
325 for(TetraCorner corner = X ; corner < NO_TET_CORNER ; corner = TetraCorner(corner + 1))
327 if(testSurfaceRayIntersection(corner))
329 double* ptB = new double[3];
330 copyVector3(&COORDS_TET_CORNER[3 * corner], ptB);
331 _polygonB.push_back(ptB);
332 LOG(3,"Surface-ray (corner " << strTC(corner) << "): " << vToStr(ptB) << " added to B");
336 // -- segment intersections
337 for(TriSegment seg = PQ ; seg < NO_TRI_SEGMENT ; seg = TriSegment(seg + 1))
342 // check beforehand which double-products are zero.
343 for(DoubleProduct dp = C_YZ; dp < NO_DP; dp = DoubleProduct(dp + 1))
344 isZero[dp] = (calcStableC(seg, dp) == 0.0);
347 for(TetraFacet facet = OYZ ; facet < NO_TET_FACET ; facet = TetraFacet(facet + 1))
349 // is this test worth it?
351 !isZero[DP_FOR_SEG_FACET_INTERSECTION[3*facet]] &&
352 !isZero[DP_FOR_SEG_FACET_INTERSECTION[3*facet + 1]] &&
353 !isZero[DP_FOR_SEG_FACET_INTERSECTION[3*facet + 2]];
355 if(doTest && testSegmentFacetIntersection(seg, facet))
357 double* ptA = new double[3];
358 calcIntersectionPtSegmentFacet(seg, facet, ptA);
359 _polygonA.push_back(ptA);
360 LOG(3,"Segment-facet (facet " << strTF(facet) << ", seg " << strTriS(seg) << "): " << vToStr(ptA) << " added to A");
363 double* ptB = new double[3];
364 copyVector3(ptA, ptB);
365 _polygonB.push_back(ptB);
366 LOG(3,"Segment-facet (facet " << strTF(facet) << ", seg " << strTriS(seg) << "): " << vToStr(ptB) << " added to B");
373 for(TetraEdge edge = OX ; edge <= ZX ; edge = TetraEdge(edge + 1))
375 const DoubleProduct edge_dp = DoubleProduct(edge);
377 if(isZero[edge_dp] && testSegmentEdgeIntersection(seg, edge))
379 double* ptA = new double[3];
380 calcIntersectionPtSegmentEdge(seg, edge, ptA);
381 _polygonA.push_back(ptA);
382 LOG(3,"Segment-edge (edge " << strTE(edge) << ", seg " << strTriS(seg) << "): " << vToStr(ptA) << " added to A");
385 double* ptB = new double[3];
386 copyVector3(ptA, ptB);
387 _polygonB.push_back(ptB);
388 LOG(3,"Segment-edge (edge " << strTE(edge) << ", seg " << strTriS(seg) << "): " << vToStr(ptA) << " added to B");
394 for(TetraCorner corner = O ; corner < NO_TET_CORNER ; corner = TetraCorner(corner + 1))
397 isZero[DoubleProduct( EDGES_FOR_CORNER[3*corner] )] &&
398 isZero[DoubleProduct( EDGES_FOR_CORNER[3*corner+1] )] &&
399 isZero[DoubleProduct( EDGES_FOR_CORNER[3*corner+2] )];
401 if(doTest && testSegmentCornerIntersection(seg, corner))
403 double* ptA = new double[3];
404 copyVector3(&COORDS_TET_CORNER[3 * corner], ptA);
405 _polygonA.push_back(ptA);
406 LOG(3,"Segment-corner (corner " << strTC(corner) << ", seg " << strTriS(seg) << "): " << vToStr(ptA) << " added to A");
409 double* ptB = new double[3];
410 _polygonB.push_back(ptB);
411 copyVector3(&COORDS_TET_CORNER[3 * corner], ptB);
412 LOG(3,"Segment-corner (corner " << strTC(corner) << ", seg " << strTriS(seg) << "): " << vToStr(ptB) << " added to B");
418 for(TetraCorner corner = X ; corner < NO_TET_CORNER ; corner = TetraCorner(corner + 1))
420 if(isZero[DP_SEGMENT_RAY_INTERSECTION[7*(corner-1)]] && testSegmentRayIntersection(seg, corner))
422 double* ptB = new double[3];
423 copyVector3(&COORDS_TET_CORNER[3 * corner], ptB);
424 _polygonB.push_back(ptB);
425 LOG(3,"Segment-ray (corner " << strTC(corner) << ", seg " << strTriS(seg) << "): " << vToStr(ptB) << " added to B");
429 // segment - halfstrip
430 for(TetraEdge edge = XY ; edge <= ZX ; edge = TetraEdge(edge + 1))
434 const int edgeIdx = int(edge) - 3; // offset since we only care for edges XY - ZX
436 !isZero[DP_FOR_HALFSTRIP_INTERSECTION[4*edgeIdx]] &&
437 !isZero[DP_FOR_HALFSTRIP_INTERSECTION[4*edgeIdx+1]];
440 if(doTest && testSegmentHalfstripIntersection(seg, edge))
442 if(testSegmentHalfstripIntersection(seg, edge))
444 double* ptB = new double[3];
445 calcIntersectionPtSegmentHalfstrip(seg, edge, ptB);
446 _polygonB.push_back(ptB);
447 LOG(3,"Segment-halfstrip : " << vToStr(ptB) << " added to B");
453 for(TriCorner corner = P ; corner < NO_TRI_CORNER ; corner = TriCorner(corner + 1))
455 // { XYZ - inclusion only possible if in Tetrahedron?
457 if(testCornerInTetrahedron(corner))
459 double* ptA = new double[3];
460 copyVector3(&_coords[5*corner], ptA);
461 _polygonA.push_back(ptA);
462 LOG(3,"Inclusion tetrahedron (corner " << strTriC(corner) << "): " << vToStr(ptA) << " added to A");
466 if(testCornerOnXYZFacet(corner))
468 double* ptB = new double[3];
469 copyVector3(&_coords[5*corner], ptB);
470 _polygonB.push_back(ptB);
471 LOG(3,"Inclusion XYZ-plane (corner " << strTriC(corner) << "): " << vToStr(ptB) << " added to B");
474 // projection on XYZ - facet
475 if(testCornerAboveXYZFacet(corner))
477 double* ptB = new double[3];
478 copyVector3(&_coords[5*corner], ptB);
479 ptB[2] = 1 - ptB[0] - ptB[1]; // lower z to project on XYZ
480 assert(epsilonEqual(ptB[0]+ptB[1]+ptB[2] - 1, 0.0));
481 _polygonB.push_back(ptB);
482 LOG(3,"Projection XYZ-plane (corner " << strTriC(corner) << "): " << vToStr(ptB) << " added to B");
490 * Calculates the intersection polygon A, performing the intersection tests
491 * and storing the corresponding point in the vector _polygonA.
493 * @post _polygonA contains the intersection polygon A.
496 void TransformedTriangle::calculateIntersectionPolygon()
498 assert(_polygonA.size() == 0);
499 // avoid reallocations in push_back() by pre-allocating enough memory
500 // we should never have more than 20 points
501 _polygonA.reserve(20);
502 // -- surface intersections
504 for(TetraEdge edge = OX ; edge <= ZX ; edge = TetraEdge(edge + 1))
506 if(testSurfaceEdgeIntersection(edge))
508 double* ptA = new double[3];
509 calcIntersectionPtSurfaceEdge(edge, ptA);
510 _polygonA.push_back(ptA);
511 LOG(3,"Surface-edge : " << vToStr(ptA) << " added to A ");
515 // -- segment intersections
516 for(TriSegment seg = PQ ; seg < NO_TRI_SEGMENT ; seg = TriSegment(seg + 1))
521 // check beforehand which double-products are zero
522 // Test for "== 0.0" here is OK since doubleProduct has been fixed for rounding to zero already.
523 for(DoubleProduct dp = C_YZ; dp < NO_DP; dp = DoubleProduct(dp + 1))
524 isZero[dp] = (calcStableC(seg, dp) == 0.0);
527 for(TetraFacet facet = OYZ ; facet < NO_TET_FACET ; facet = TetraFacet(facet + 1))
529 // is this test worth it?
531 !isZero[DP_FOR_SEG_FACET_INTERSECTION[3*facet]] &&
532 !isZero[DP_FOR_SEG_FACET_INTERSECTION[3*facet + 1]] &&
533 !isZero[DP_FOR_SEG_FACET_INTERSECTION[3*facet + 2]];
535 if(doTest && testSegmentFacetIntersection(seg, facet))
537 double* ptA = new double[3];
538 calcIntersectionPtSegmentFacet(seg, facet, ptA);
539 _polygonA.push_back(ptA);
540 LOG(3,"Segment-facet : " << vToStr(ptA) << " added to A");
545 for(TetraEdge edge = OX ; edge <= ZX ; edge = TetraEdge(edge + 1))
547 const DoubleProduct edge_dp = DoubleProduct(edge);
549 if(isZero[edge_dp] && testSegmentEdgeIntersection(seg, edge))
551 double* ptA = new double[3];
552 calcIntersectionPtSegmentEdge(seg, edge, ptA);
553 _polygonA.push_back(ptA);
554 LOG(3,"Segment-edge : " << vToStr(ptA) << " added to A");
559 for(TetraCorner corner = O ; corner < NO_TET_CORNER ; corner = TetraCorner(corner + 1))
562 isZero[DoubleProduct( EDGES_FOR_CORNER[3*corner] )] &&
563 isZero[DoubleProduct( EDGES_FOR_CORNER[3*corner+1] )] &&
564 isZero[DoubleProduct( EDGES_FOR_CORNER[3*corner+2] )];
566 if(doTest && testSegmentCornerIntersection(seg, corner))
568 double* ptA = new double[3];
569 copyVector3(&COORDS_TET_CORNER[3 * corner], ptA);
570 _polygonA.push_back(ptA);
571 LOG(3,"Segment-corner : " << vToStr(ptA) << " added to A");
578 for(TriCorner corner = P ; corner < NO_TRI_CORNER ; corner = TriCorner(corner + 1))
580 // { XYZ - inclusion only possible if in Tetrahedron?
582 if(testCornerInTetrahedron(corner))
584 double* ptA = new double[3];
585 copyVector3(&_coords[5*corner], ptA);
586 _polygonA.push_back(ptA);
587 LOG(3,"Inclusion tetrahedron : " << vToStr(ptA) << " added to A");
596 * Returns the surface of polygon A.
598 * @return the surface of polygon A.
600 double TransformedTriangle::calculateSurfacePolygon()
602 const std::size_t nbPoints = _polygonA.size();
604 double sum[3] = {0., 0., 0.};
606 for(std::size_t i = 0 ; i < nbPoints ; ++i)
608 const double *const ptCurr = _polygonA[i]; // pt "i"
609 const double *const ptNext = _polygonA[(i + 1) % nbPoints]; // pt "i+1" (pt nbPoints == pt 0)
611 cross(ptCurr, ptNext, pdt);
615 const double surface = norm(sum) * 0.5;
616 LOG(2,"Surface is " << surface);
621 * Calculates the barycenters of the given intersection polygon.
623 * @pre the intersection polygons have been calculated with calculateIntersectionAndProjectionPolygons()
625 * @param poly one of the two intersection polygons
626 * @param barycenter array of three doubles where barycenter is stored
629 void TransformedTriangle::calculatePolygonBarycenter(const IntersectionPolygon poly, double* barycenter)
631 LOG(3,"--- Calculating polygon barycenter");
633 // get the polygon points
634 std::vector<double*>& polygon = (poly == A) ? _polygonA : _polygonB;
636 // calculate barycenter
637 const std::size_t m = polygon.size();
639 for(int j = 0 ; j < 3 ; ++j)
646 for(std::size_t i = 0 ; i < m ; ++i)
648 const double* pt = polygon[i];
649 for(int j = 0 ; j < 3 ; ++j)
651 barycenter[j] += pt[j] / double(m);
655 LOG(3,"Barycenter is " << vToStr(barycenter));
659 * Sorts the given intersection polygon in circular order around its barycenter.
660 * @pre the intersection polygons have been calculated with calculateIntersectionAndProjectionPolygons()
661 * @post the vertices in _polygonA and _polygonB are sorted in circular order around their
662 * respective barycenters
664 * @param poly one of the two intersection polygons
665 * @param barycenter array of three doubles with the coordinates of the barycenter
668 void TransformedTriangle::sortIntersectionPolygon(const IntersectionPolygon poly, const double* barycenter)
670 LOG(3,"--- Sorting polygon ...");
672 using INTERP_KERNEL::ProjectedCentralCircularSortOrder;
673 typedef ProjectedCentralCircularSortOrder SortOrder; // change is only necessary here and in constructor
674 typedef SortOrder::CoordType CoordType;
676 // get the polygon points
677 std::vector<double*>& polygon = (poly == A) ? _polygonA : _polygonB;
679 if(polygon.size() == 0)
682 // determine type of sorting
683 CoordType type = SortOrder::XY;
684 if(poly == A && !isTriangleInclinedToFacet( OXY )) // B is on h = 0 plane -> ok
686 // NB : the following test is never true if we have eliminated the
687 // triangles parallel to x == 0 and y == 0 in calculateIntersectionVolume().
688 // We keep the test here anyway, to avoid interdependency.
690 // is triangle inclined to x == 0 ?
691 if(isTriangleInclinedToFacet(OZX))
693 type = SortOrder::XZ;
695 else //if(isTriangleParallelToFacet(OYZ))
697 type = SortOrder::YZ;
701 // create order object
702 SortOrder order(barycenter, type);
704 // sort vector with this object
705 // NB : do not change place of first object, with respect to which the order
707 sort((polygon.begin()), polygon.end(), order);
709 LOG(3,"Sorted polygon is ");
710 for(size_t i = 0 ; i < polygon.size() ; ++i)
712 LOG(3,vToStr(polygon[i]));
718 * Calculates the volume between the given polygon and the z = 0 plane.
720 * @pre the intersection polygones have been calculated with calculateIntersectionAndProjectionPolygons(),
721 * and they have been sorted in circular order with sortIntersectionPolygons(void)
723 * @param poly one of the two intersection polygons
724 * @param barycenter array of three doubles with the coordinates of the barycenter
725 * @return the volume between the polygon and the z = 0 plane
728 double TransformedTriangle::calculateVolumeUnderPolygon(IntersectionPolygon poly, const double* barycenter)
730 LOG(2,"--- Calculating volume under polygon");
732 // get the polygon points
733 std::vector<double*>& polygon = (poly == A) ? _polygonA : _polygonB;
736 const std::size_t m = polygon.size();
738 for(std::size_t i = 0 ; i < m ; ++i)
740 const double* ptCurr = polygon[i]; // pt "i"
741 const double* ptNext = polygon[(i + 1) % m]; // pt "i+1" (pt m == pt 0)
743 const double factor1 = ptCurr[2] + ptNext[2] + barycenter[2];
744 const double factor2 =
745 ptCurr[0]*(ptNext[1] - barycenter[1])
746 + ptNext[0]*(barycenter[1] - ptCurr[1])
747 + barycenter[0]*(ptCurr[1] - ptNext[1]);
748 vol += (factor1 * factor2) / 6.0;
751 LOG(2,"Abs. Volume is " << vol);
756 ////////////////////////////////////////////////////////////////////////////////////
757 // Detection of (very) degenerate cases /////////////
758 ////////////////////////////////////////////////////////////////////////////////////
761 * Checks if the triangle lies in the plane of a given facet
763 * @param facet one of the facets of the tetrahedron
764 * @return true if PQR lies in the plane of the facet, false if not
766 bool TransformedTriangle::isTriangleInPlaneOfFacet(const TetraFacet facet) const
768 // coordinate to check
769 const int coord = static_cast<int>(facet);
771 for(TriCorner c = P ; c < NO_TRI_CORNER ; c = TriCorner(c + 1))
772 if(_coords[5*c + coord] != 0.0)
779 * Checks if the triangle is parallel to the given facet
781 * @param facet one of the facets of the unit tetrahedron
782 * @return true if triangle is parallel to facet, false if not
784 bool TransformedTriangle::isTriangleParallelToFacet(const TetraFacet facet) const
786 // coordinate to check
787 const int coord = static_cast<int>(facet);
788 return (_coords[5*P + coord] == _coords[5*Q + coord]) && (_coords[5*P + coord] == _coords[5*R + coord]);
792 * Checks if the triangle is not perpedicular to the given facet
794 * @param facet one of the facets of the unit tetrahedron
795 * @return zero if the triangle is perpendicular to the facet,
796 * else 1 or -1 depending on the sign of cross product of facet edges
798 int TransformedTriangle::isTriangleInclinedToFacet(const TetraFacet facet) const
800 // coordinate to check
801 const int coord = static_cast<int>(facet);
802 const int ind1 = ( coord+1 ) % 3, ind2 = ( coord+2 ) % 3;
803 const double uv_xy[4] =
806 _coords[5*Q+ind1] - _coords[5*P+ind1], _coords[5*Q+ind2] - _coords[5*P+ind2],
808 _coords[5*R+ind1] - _coords[5*P+ind1], _coords[5*R+ind2] - _coords[5*P+ind2]
811 double sign = uv_xy[0] * uv_xy[3] - uv_xy[1] * uv_xy[2];
812 if(epsilonEqual(sign, 0.))
814 return (sign < 0.) ? -1 : (sign > 0.) ? 1 : 0;
818 * Determines whether the triangle is below the z-plane.
820 * @return true if the z-coordinate of the three corners of the triangle are all less than 0, false otherwise.
822 bool TransformedTriangle::isTriangleBelowTetraeder() const
824 for(TriCorner c = P ; c < NO_TRI_CORNER ; c = TriCorner(c + 1))
825 // check z-coords for all points
826 if(_coords[5*c + 2] >= 0.0)
833 * Prints the coordinates of the triangle to std::cout
836 void TransformedTriangle::dumpCoords() const
838 std::cout << "Coords : ";
839 for(int i = 0 ; i < 3; ++i)
840 std::cout << vToStr(&_coords[5*i]) << ",";
842 std::cout << std::endl;