add note explaining last bits to change to make meshers thread-safe

Mesh/Generator.cpp

@@ -403,18 +403,31 @@ static void Mesh2D(GModel *m)
   double t1 = Cpu();
 
   // skip short mesh edges
-  geomTresholdVertexEquivalence inst (m);
+  geomTresholdVertexEquivalence inst(m);
 
   // boundary layers are special: their generation (including vertices
   // and curve meshes) is global as it depends on a smooth normal
   // field generated from the surface mesh of the source surfaces
   if(!Mesh2DWithBoundaryLayers(m)){
+
+#if 1
     std::for_each(m->firstFace(), m->lastFace(), meshGFace());
+#else 
+    // test openmp
+    std::vector<GFace*> faces;
+    faces.insert(faces.begin(), m->firstFace(), m->lastFace());
+#pragma omp parallel for schedule(dynamic)
+    for(unsigned int i = 0; i < faces.size(); i++){
+      meshGFace mesher;
+      mesher(faces[i]);
+    }
+#endif
+
     int nIter = 0;
     while(1){
       meshGFace mesher;
       int nbPending = 0;
-      for(GModel::fiter it = m->firstFace() ; it!=m->lastFace(); ++it){
+      for(GModel::fiter it = m->firstFace(); it != m->lastFace(); ++it){
         if ((*it)->meshStatistics.status == GFace::PENDING){
           mesher(*it);
           nbPending++;

Mesh/meshGFace.cpp

@@ -368,6 +368,11 @@ static bool recover_medge_old(BDS_Mesh *m, GEdge *ge, std::set<EdgeToRecover> *e
 // Builds An initial triangular mesh that respects the boundaries of
 // the domain, including embedded points and surfaces
 
+// FIXME: to make the algorithm thread-safe, we need to change the way
+// we renumber the boundary vertices (and the associated u/v reparam):
+// using setIndex leads to unpredicatbel results if meshing
+// concurrently two surfaces that share a common edge!
+
 static bool gmsh2DMeshGenerator(GFace *gf, int RECUR_ITER, 
                                 bool repairSelfIntersecting1dMesh, bool debug = true)
 {