1 // Gmsh - Copyright (C) 1997-2021 C. Geuzaine, J.-F. Remacle
2 //
3 // See the LICENSE.txt file in the Gmsh root directory for license information.
4 // Please report all issues on https://gitlab.onelab.info/gmsh/gmsh/issues.
5
6 #include <set>
7 #include "GModel.h"
8 #include "MLine.h"
9 #include "ExtrudeParams.h"
10 #include "GmshMessage.h"
11
createElements(GEdge * ge)12 static void createElements(GEdge *ge)
13 {
14 // create elements
15 for(std::size_t i = 0; i < ge->mesh_vertices.size() + 1; i++) {
16 MVertex *v0 = (i == 0) ? ge->getBeginVertex()->mesh_vertices[0] :
17 ge->mesh_vertices[i - 1];
18 MVertex *v1 = (i == ge->mesh_vertices.size()) ?
19 ge->getEndVertex()->mesh_vertices[0] :
20 ge->mesh_vertices[i];
21 MLine *newElem = new MLine(v0, v1);
22 ge->lines.push_back(newElem);
23 }
24 }
25
extrudeMesh(GVertex * from,GEdge * to)26 static void extrudeMesh(GVertex *from, GEdge *to)
27 {
28 ExtrudeParams *ep = to->meshAttributes.extrude;
29
30 MVertex *v = from->mesh_vertices[0];
31 for(int j = 0; j < ep->mesh.NbLayer; j++) {
32 for(int k = 0; k < ep->mesh.NbElmLayer[j]; k++) {
33 double x = v->x(), y = v->y(), z = v->z();
34 ep->Extrude(j, k + 1, x, y, z);
35 if(j != ep->mesh.NbLayer - 1 || k != ep->mesh.NbElmLayer[j] - 1) {
36 Range<double> r = to->parBounds(0);
37 double t = r.low() + ep->u(j, k + 1) * (r.high() - r.low());
38 MEdgeVertex *newv = new MEdgeVertex(x, y, z, to, t);
39 to->mesh_vertices.push_back(newv);
40 }
41 }
42 }
43 createElements(to);
44 }
45
copyMesh(GEdge * from,GEdge * to)46 static void copyMesh(GEdge *from, GEdge *to)
47 {
48 ExtrudeParams *ep = to->meshAttributes.extrude;
49
50 int direction = (ep->geo.Source > 0) ? 1 : -1;
51
52 Range<double> u_bounds = from->parBounds(0);
53 double u_min = u_bounds.low();
54 double u_max = u_bounds.high();
55
56 #if 0
57 // old version, which directly uses nodes; this can lead to unexpected results
58 // if the nodes in from->mesh_vertices.size() are not sorted, which can happen
59 // e.g. if createTopology() has been called
60 for(std::size_t i = 0; i < from->mesh_vertices.size(); i++) {
61 int index = (direction < 0) ? (from->mesh_vertices.size() - 1 - i) : i;
62 MVertex *v = from->mesh_vertices[index];
63 double x = v->x(), y = v->y(), z = v->z();
64 ep->Extrude(ep->mesh.NbLayer - 1, ep->mesh.NbElmLayer[ep->mesh.NbLayer - 1],
65 x, y, z);
66 double u;
67 v->getParameter(0, u);
68 double newu = (direction > 0) ? u : (u_max - u + u_min);
69 MEdgeVertex *newv = new MEdgeVertex(x, y, z, to, newu);
70 to->mesh_vertices.push_back(newv);
71 }
72 #else
73 // so it's better to go back to the elements, which are assumed to be stored
74 // in the correct order
75 for(int i = 0; i < (int)from->lines.size() - 1; i++) {
76 int index = (direction < 0) ? (from->lines.size() - i - 2) : i;
77 MVertex *v = from->lines[index]->getVertex(1);
78 double x = v->x(), y = v->y(), z = v->z();
79 ep->Extrude(ep->mesh.NbLayer - 1, ep->mesh.NbElmLayer[ep->mesh.NbLayer - 1],
80 x, y, z);
81 double u;
82 v->getParameter(0, u);
83 double newu = (direction > 0) ? u : (u_max - u + u_min);
84 MEdgeVertex *newv = new MEdgeVertex(x, y, z, to, newu);
85 to->mesh_vertices.push_back(newv);
86 }
87 #endif
88
89 createElements(to);
90 }
91
MeshExtrudedCurve(GEdge * ge)92 int MeshExtrudedCurve(GEdge *ge)
93 {
94 ExtrudeParams *ep = ge->meshAttributes.extrude;
95
96 if(!ep || !ep->mesh.ExtrudeMesh) return 0;
97
98 if(!ge->getBeginVertex() || !ge->getEndVertex()) {
99 Msg::Error("Cannot extrude curve %d with no begin or end point", ge->tag());
100 return 0;
101 }
102
103 Msg::Info("Meshing curve %d (Extruded)", ge->tag());
104
105 if(ep->geo.Mode == EXTRUDED_ENTITY) {
106 // curve is extruded from a point
107 extrudeMesh(ge->getBeginVertex(), ge);
108 }
109 else {
110 GEdge *from = ge->model()->getEdgeByTag(std::abs(ep->geo.Source));
111 // curve is a copy of another curve (the "top" of the extrusion)
112 if(!from) {
113 Msg::Error("Unknown source curve %d for extrusion", ep->geo.Source);
114 return 0;
115 }
116 else if(from->geomType() != GEntity::DiscreteCurve &&
117 from->meshStatistics.status != GEdge::DONE) {
118 // cannot mesh this edge yet: will do it later
119 return 1;
120 }
121
122 copyMesh(from, ge);
123 if(ge->getMeshMaster() == from) {
124 // explicit periodic constraint, to store node correspondance
125 ge->setMeshMaster(from, ge->affineTransform);
126 }
127 }
128
129 ge->meshStatistics.status = GEdge::DONE;
130 return 1;
131 }
132