c++ versions of t2.geo and t16.geo

demos/api/t16.cpp

+#include <gmsh.h>
+
+// this reimplements gmsh/tutorial/t16.geo
+
+int main(int argc, char **argv)
+{
+  gmshInitialize(argc, argv);
+  gmshOptionSetNumber("General.Terminal", 1);
+
+  gmshModelCreate("boolean");
+
+  int o;
+  std::vector<std::pair<int, int> > ov;
+  std::vector<std::vector<std::pair<int, int> > > ovv;
+  gmshModelOccAddBox(1, 0,0,0, 1,1,1, o);
+  gmshModelOccAddBox(2, 0,0,0, 0.5,0.5,0.5, o);
+  gmshModelOccBooleanDifference(3, {{3,1}}, {{3,2}}, ov, ovv);
+  double x = 0, y = 0.75, z = 0, r = 0.09 ;
+  std::vector<std::pair<int, int> > holes;
+  for(int t = 1; t <= 5; t++){
+    x += 0.166 ;
+    z += 0.166 ;
+    gmshModelOccAddSphere(3 + t, x,y,z,r, o);
+    holes.push_back({3, 3 + t});
+  }
+  gmshModelOccBooleanFragments(-1, {{3,3}}, holes, ov, ovv);
+
+  gmshModelOccSynchronize();
+
+  double lcar1 = .1;
+  double lcar2 = .0005;
+  double lcar3 = .055;
+
+  gmshModelGetEntities(ov);
+  gmshModelSetMeshSize(ov, lcar1);
+  gmshModelGetBoundary(holes, ov, false, false, true);
+  gmshModelSetMeshSize(ov, lcar3);
+
+  double eps = 1e-3;
+  gmshModelGetEntitiesInBoundingBox(0.5-eps, 0.5-eps, 0.5-eps,
+                                    0.5+eps, 0.5+eps, 0.5+eps, ov, 0);
+  gmshModelSetMeshSize(ov, lcar2);
+
+  gmshModelMesh(3);
+
+  gmshExport("t16.msh");
+
+  gmshFinalize();
+  return 0;
+}
+

demos/api/t2.cpp

+#include <gmsh.h>
+
+// this reimplements gmsh/tutorial/t2.geo
+
+int main(int argc, char **argv)
+{
+  gmshInitialize(argc, argv);
+  gmshOptionSetNumber("General.Terminal", 1);
+
+  gmshModelCreate("t2");
+
+  // copy/paste from t1.cpp
+  double lc = 1e-2;
+  int o;
+  gmshModelGeoAddPoint(1, 0, 0, 0, o, lc);
+  gmshModelGeoAddPoint(2, .1, 0,  0, o, lc);
+  gmshModelGeoAddPoint(3, .1, .3, 0, o, lc);
+  gmshModelGeoAddPoint(4, 0,  .3, 0, o, lc);
+
+  gmshModelGeoAddLine(1, 1, 2, o);
+  gmshModelGeoAddLine(2, 3, 2, o);
+  gmshModelGeoAddLine(3, 3, 4, o);
+  gmshModelGeoAddLine(4, 4, 1, o);
+
+  gmshModelGeoAddLineLoop(1, {4, 1, -2, 3}, o);
+  gmshModelGeoAddPlaneSurface(1, {1}, o);
+  gmshModelAddPhysicalGroup(0, 1, {1, 2});
+  gmshModelAddPhysicalGroup(1, 2, {1, 2});
+  gmshModelAddPhysicalGroup(2, 6, {1});
+  gmshModelSetPhysicalName(2, 6, "My surface");
+  // end copy/paste
+
+  gmshModelGeoAddPoint(5, 0, .4, 0, o, lc);
+  gmshModelGeoAddLine(5, 4, 5, o);
+  gmshModelGeoTranslate({{0, 3}}, -0.05, 0, 0);
+
+  std::vector<std::pair<int, int> > ov, ov2;
+  gmshModelGeoCopy({{0, 3}}, ov);
+  gmshModelGeoTranslate(ov, 0, 0.1, 0);
+
+  gmshModelGeoAddLine(7, 3, ov[0].second, o);
+  gmshModelGeoAddLine(8, ov[0].second, 5, o);
+  gmshModelGeoAddLineLoop(10, {5,-8,-7,3}, o);
+  gmshModelGeoAddPlaneSurface(11, {10}, o);
+
+  gmshModelGeoCopy({{2, 1}, {2, 11}}, ov);
+  gmshModelGeoTranslate(ov, 0.12, 0, 0);
+
+  std::printf("New surfaces '%d' and '%d'\n", ov[0].second, ov[1].second);
+
+  gmshModelGeoAddPoint(100, 0., 0.3, 0.13, o, lc);
+  gmshModelGeoAddPoint(101, 0.08, 0.3, 0.1, o, lc);
+  gmshModelGeoAddPoint(102, 0.08, 0.4, 0.1, o, lc);
+  gmshModelGeoAddPoint(103, 0., 0.4, 0.13, o, lc);
+
+  gmshModelGeoAddLine(110, 4, 100, o);
+  gmshModelGeoAddLine(111, 3, 101, o);
+  gmshModelGeoAddLine(112, 6, 102, o);
+  gmshModelGeoAddLine(113, 5, 103, o);
+  gmshModelGeoAddLine(114, 103, 100, o);
+  gmshModelGeoAddLine(115, 100, 101, o);
+  gmshModelGeoAddLine(116, 101, 102, o);
+  gmshModelGeoAddLine(117, 102, 103, o);
+
+  gmshModelGeoAddLineLoop(118, {115, -111, 3, 110}, o);
+  gmshModelGeoAddPlaneSurface(119, {118}, o);
+  gmshModelGeoAddLineLoop(120, {111, 116, -112, -7}, o);
+  gmshModelGeoAddPlaneSurface(121, {120}, o);
+  gmshModelGeoAddLineLoop(122, {112, 117, -113, -8}, o);
+  gmshModelGeoAddPlaneSurface(123, {122}, o);
+  gmshModelGeoAddLineLoop(124, {114, -110, 5, 113}, o);
+  gmshModelGeoAddPlaneSurface(125, {124}, o);
+  gmshModelGeoAddLineLoop(126, {115, 116, 117, 114}, o);
+  gmshModelGeoAddPlaneSurface(127, {126}, o);
+
+  gmshModelGeoAddSurfaceLoop(128, {127, 119, 121, 123, 125, 11}, o);
+  gmshModelGeoAddVolume(129, {128}, o);
+
+  gmshModelGeoExtrude({ov[1]}, 0, 0, 0.12, ov2);
+
+  gmshModelGeoSetMeshSize({{0,103}, {0,105}, {0,109}, {0,102}, {0,28},
+                           {0, 24}, {0,6}, {0,5}}, lc * 3);
+
+  gmshModelAddPhysicalGroup(3, 1, {129,130});
+  gmshModelSetPhysicalName(3, 1, "The volume");
+
+  gmshModelGeoSynchronize();
+
+  gmshModelMesh(3);
+
+  gmshExport("t2.msh");
+
+  gmshFinalize();
+  return 0;
+}