Polyhedra generate_polyhedra_from_points(const std::vector<std::array<double,3> >& vertices) { std::vector<Point_3> points(vertices.size()); for(int i=0;i<(int)vertices.size();i++) points[i] = Point_3(vertices[i][0],vertices[i][1],vertices[i][2]); Polyhedron_3 poly; CGAL::convex_hull_3(points.begin(), points.end(), poly); std::transform(poly.facets_begin(), poly.facets_end(), poly.planes_begin(), Plane_from_facet()); for(Halfedge_iterator half=poly.halfedges_begin();half!=poly.halfedges_end();++half) { Point_3 v1 = half->vertex()->point(); Point_3 v2 = half->next()->vertex()->point(); Point_3 v3 = half->next()->next()->vertex()->point(); Point_3 v4 = half->opposite()->vertex()->point(); Point_3 v5 = half->opposite()->next()->vertex()->point(); Point_3 v6 = half->opposite()->next()->next()->vertex()->point(); if(coplanar_handmade(v1,v2,v3,v4)&&coplanar_handmade(v1,v2,v3,v5)&&coplanar_handmade(v1,v2,v3,v6)&& coplanar_handmade(v1,v2,v4,v5)&&coplanar_handmade(v1,v2,v4,v6)&&coplanar_handmade(v1,v2,v5,v6)&& coplanar_handmade(v1,v3,v4,v5)&&coplanar_handmade(v1,v3,v4,v6)&&coplanar_handmade(v1,v4,v5,v6)&& coplanar_handmade(v2,v3,v4,v5)&&coplanar_handmade(v2,v3,v4,v6)&&coplanar_handmade(v2,v3,v5,v6)&& coplanar_handmade(v2,v4,v5,v6)&&coplanar_handmade(v1,v3,v5,v6)&&coplanar_handmade(v3,v4,v5,v6)) { poly.join_facet(half); half=poly.halfedges_begin(); } } int cur = 0; for(auto it=poly.points_begin(); it!=poly.points_end(); it++, cur++) points[cur] = *it; cur = 0; std::vector<std::vector<int> > faces; for(Facet_iterator i=poly.facets_begin(); i!=poly.facets_end(); i++) { faces.push_back(std::vector<int>()); Halfedge_facet_circulator j = i->facet_begin(); do {faces[cur].push_back(std::distance(poly.vertices_begin(), j->vertex()));} while (++j != i->facet_begin()); cur++; } return Polyhedra{points,faces}; }
void CGALConvexHull3D::run(const MatrixFr& points) { std::list<Point_3> cgal_pts; const size_t num_pts = points.rows(); const size_t dim = points.cols(); if (dim != 3) { std::stringstream err_msg; err_msg << "Invalid dim: " << dim << " Expect dim=3."; throw RuntimeError(err_msg.str()); } for (size_t i=0; i<num_pts; i++) { const VectorF& p = points.row(i); cgal_pts.push_back(Point_3(p[0], p[1], p[2])); } Polyhedron_3 hull; CGAL::convex_hull_3(cgal_pts.begin(), cgal_pts.end(), hull); assert(hull.is_closed()); assert(hull.is_pure_triangle()); const size_t num_vertices = hull.size_of_vertices(); const size_t num_faces = hull.size_of_facets(); m_vertices.resize(num_vertices, dim); m_faces.resize(num_faces, 3); size_t vertex_count=0; for (auto itr=hull.vertices_begin(); itr!=hull.vertices_end(); itr++) { const Point_3& p = itr->point(); m_vertices.coeffRef(vertex_count, 0) = p.x(); m_vertices.coeffRef(vertex_count, 1) = p.y(); m_vertices.coeffRef(vertex_count, 2) = p.z(); itr->id() = vertex_count; vertex_count++; } size_t face_count=0; for (auto f_itr=hull.facets_begin(); f_itr!=hull.facets_end(); f_itr++) { size_t edge_count=0; auto h_itr = f_itr->facet_begin(); do { m_faces.coeffRef(face_count, edge_count) = h_itr->vertex()->id(); edge_count++; h_itr++; } while (h_itr != f_itr->facet_begin()); face_count++; } compute_index_map(points); reorient_faces(); }
void CGALDelaunay::TriangulateUsingCGAL(vector<Vertex_handle> * DelaunayTriangulationVertices, vector<vector<float> > * PointsToBeInserted, Triangulation * T, vector<float> *bufferPointer, vector<float> *colorPointer, int*totalVertices) { //CHECK TO SEE IF THE POINT TO ADD NEEDS TO BE EITHER MODIFIED OR ADDED //ROS_INFO("SIZE OF DELAUNAY VERTICES:%i", DelaunayTriangulationVertices->size()); //ROS_INFO("SIZE OF VERTICES to be added:%i", PointsToBeInserted->size()); for(int i = 0;i<PointsToBeInserted->size();i++) { vector<float> currentPoint = PointsToBeInserted->at(i); T->insert(Point(currentPoint[0],currentPoint[1], currentPoint[2])); } //CONVERT DELAUNAY TRIANGULATION TO CONVEX HULL Polyhedron_3 chull; CGAL::convex_hull_3_to_polyhedron_3(*T, chull); int count = 0; int vec3Order[] = {0,1,2}; vector<float> emptyVector; *bufferPointer = emptyVector; *colorPointer = emptyVector; for( Polyhedron_3::Facet_iterator fit = chull.facets_begin(); fit != chull.facets_end(); ++fit){ vector<Point> currentFacet; HF_circulator h = fit->facet_begin(); size_t order = 0; vector<vector<float> > TriangleVec; do { Point currentPoint = h->vertex()->point(); vector<float> tempVec; tempVec.push_back(currentPoint.x()); tempVec.push_back(currentPoint.y()); tempVec.push_back(currentPoint.z()); TriangleVec.push_back(tempVec); } while(++h != fit->facet_begin()); BufferActions::addVec3ToBuffer(vec3Order, bufferPointer, &TriangleVec, 3); BufferActions::addVec3ToBuffer(vec3Order, colorPointer, &TriangleVec, 3); count += 3; } *totalVertices= count; }
std::vector<Plane_3> renumerateFacets(Polyhedron_3 polyhedron, std::vector<SimpleEdge_3> &edges, std::map<int, int> &indices) { DEBUG_START; std::vector<Plane_3> planes; for (const SimpleEdge_3 &edge : edges) { indices.insert(std::pair<int, int>(edge.iForward, UNINITIALIZED_MAP_VALUE)); indices.insert(std::pair<int, int>(edge.iBackward, UNINITIALIZED_MAP_VALUE)); } int i = 0; for (auto &pair : indices) { pair.second = i++; } i = 0; for (auto facet = polyhedron.facets_begin(); facet < polyhedron.facets_end(); ++facet) { ASSERT(facet->id == i); if (indices.find(i) != indices.end()) { planes.push_back(facet->plane()); } ++i; } for (auto &pair : indices) { std::cout << "map[" << pair.first << "] = " << pair.second << ", plane: " << planes[pair.second] << std::endl; } for (SimpleEdge_3 &edge : edges) { edge.iForward = indices[edge.iForward]; edge.iBackward = indices[edge.iBackward]; } DEBUG_END; return planes; }
Polyhedron_3 obtainPolyhedron(Polyhedron_3 initialP, std::map<int, int> map, IpoptTopologicalCorrector *FTNLP) { DEBUG_START; std::vector<Vector_3> directions = FTNLP->getDirections(); std::vector<double> values = FTNLP->getValues(); std::vector<Plane_3> planes(initialP.size_of_facets()); unsigned iFacet = 0; for (auto I = initialP.facets_begin(), E = initialP.facets_end(); I != E; ++I) { auto it = map.find(iFacet); if (it != map.end()) { int i = it->second; Vector_3 u = directions[i]; double h = values[i]; ASSERT(h > 0); planes[iFacet] = Plane_3(-u.x(), -u.y(), -u.z(), h); std::cout << "Changing plane #" << iFacet << ": " << I->plane() << " |--> " << planes[iFacet] << std::endl; } else { planes[iFacet] = I->plane(); } ++iFacet; } Polyhedron_3 intersection(planes); std::cout << "Change in facets number: " << initialP.size_of_facets() << " -> " << intersection.size_of_facets() << std::endl; ASSERT(initialP.size_of_facets() - intersection.size_of_facets() < map.size() && "It seems that all extracted facets have gone"); DEBUG_END; return intersection; }
int main() { CGAL::Random_points_in_sphere_3<Point_3, PointCreator> gen(100.0); // generate 250 points randomly on a sphere of radius 100.0 // and copy them to a vector std::vector<Point_3> points; CGAL::cpp11::copy_n( gen, 250, std::back_inserter(points) ); // define polyhedron to hold convex hull Polyhedron_3 poly; // compute convex hull of non-collinear points CGAL::convex_hull_3(points.begin(), points.end(), poly); std::cout << "The convex hull contains " << poly.size_of_vertices() << " vertices" << std::endl; // assign a plane equation to each polyhedron facet using functor Plane_from_facet std::transform( poly.facets_begin(), poly.facets_end(), poly.planes_begin(),Plane_from_facet()); return 0; }
/* FIXME: Copied from Polyhedron_io.cpp with slight modifications. */ static std::shared_ptr<Polyhedron> convertWithAssociation(Polyhedron_3 p, const Point_3 &C, const std::vector<Plane_3> &initPlanes) { /* Check for non-emptiness. */ ASSERT(p.size_of_vertices()); ASSERT(p.size_of_facets()); int numVertices = p.size_of_vertices(); int numFacets = p.size_of_facets(); /* Allocate memory for arrays. */ Vector3d *vertices = new Vector3d[numVertices]; Facet *facets = new Facet[numFacets]; /* Transform vertexes. */ int iVertex = 0; for (auto vertex = p.vertices_begin(); vertex != p.vertices_end(); ++vertex) { Point_3 point = C + vertex->point(); vertices[iVertex++] = Vector3d(point.x(), point.y(), point.z()); } /* * Transform facets. * This algorithm is based on example kindly provided at CGAL online user * manual. See example Polyhedron/polyhedron_prog_off.cpp */ int iFacet = 0; auto plane = p.planes_begin(); auto facet = p.facets_begin(); /* Iterate through the std::lists of planes and facets. */ do { int id = p.indexPlanes_[iFacet]; facets[id].id = id; /* Transform current plane. */ Plane_3 pi = centerizePlane(*plane, Point_3(-C.x(), -C.y(), -C.z()), signedDist(initPlanes[id], C)); facets[id].plane = Plane(Vector3d(pi.a(), pi.b(), pi.c()), pi.d()); /* * Iterate through the std::list of halfedges incident to the curent CGAL * facet. */ auto halfedge = facet->facet_begin(); /* Facets in polyhedral surfaces are at least triangles. */ CGAL_assertion(CGAL::circulator_size(halfedge) >= 3); facets[id].numVertices = CGAL::circulator_size(halfedge); facets[id].indVertices = new int[3 * facets[id].numVertices + 1]; /* * TODO: It's too unsafe architecture if we do such things as setting * the size of internal array outside the API functions. Moreover, it * can cause us to write memory leaks. * indFacets and numFacets should no be public members. */ int iFacetVertex = 0; do { facets[id].indVertices[iFacetVertex++] = std::distance(p.vertices_begin(), halfedge->vertex()); } while (++halfedge != facet->facet_begin()); /* Add cycling vertex to avoid assertion during printing. */ facets[id].indVertices[facets[id].numVertices] = facets[id].indVertices[0]; ASSERT(facets[id].correctPlane()); /* Increment the ID of facet. */ ++iFacet; } while (++plane != p.planes_end() && ++facet != p.facets_end()); return std::make_shared<Polyhedron>(numVertices, numFacets, vertices, facets); }