coherence of surface mesh in extrusion

Mesh/3D_Extrude.cpp

-// $Id: 3D_Extrude.cpp,v 1.14 2001-08-01 15:52:33 geuzaine Exp $
+// $Id: 3D_Extrude.cpp,v 1.15 2001-08-01 18:01:04 geuzaine Exp $
 
 #include "Gmsh.h"
 #include "Const.h"
@@ -412,9 +412,11 @@ void Extrude_Seg (Vertex * V1, Vertex * V2){
         if (are_exist (v3, v2, Tree_Ares)){
           s = Create_Simplex (v3, v2, v1, NULL);
           s->iEnt = THES->Num;
+	  s->Num = -s->Num; //Trick to tag triangles to re-extrude!
           Tree_Add (THES->Simplexes, &s);
           s = Create_Simplex (v3, v4, v2, NULL);
           s->iEnt = THES->Num;
+	  s->Num = -s->Num; //Trick to tag triangles to re-extrude!
           Tree_Add (THES->Simplexes, &s);
         }
         else{
@@ -422,9 +424,11 @@ void Extrude_Seg (Vertex * V1, Vertex * V2){
           are_cree (v1, v4, Tree_Ares);
           s = Create_Simplex (v3, v4, v1, NULL);
           s->iEnt = THES->Num;
+	  s->Num = -s->Num; //Trick to tag triangles to re-extrude!
           Tree_Add (THES->Simplexes, &s);
           s = Create_Simplex (v1, v4, v2, NULL);
           s->iEnt = THES->Num;
+	  s->Num = -s->Num; //Trick to tag triangles to re-extrude!
           Tree_Add (THES->Simplexes, &s);
         }
       }
@@ -635,6 +639,25 @@ int Extrude_Mesh (Surface * s){
 
 }
 
+static Tree_T* tmp;
+void Free_NegativeSimplex (void *a, void *b){
+  Simplex *s = *(Simplex**)a;
+  if(s){
+    if(s->Num>=0){
+      Tree_Add (tmp, &s);
+    }
+    else{
+      delete s;
+      s = NULL;
+    }
+  }
+}
+
+void Untag_NegativeSimplex (void *a, void *b){
+  Simplex *s = *(Simplex**)a;
+  if(s && s->Num<0) s->Num = -s->Num;
+}
+
 int Extrude_Mesh (Volume * v){
   int i, j;
   Surface *ss;
@@ -690,17 +713,24 @@ int Extrude_Mesh (Volume * v){
     // so that now, the surface mesh is ok (edge swapping is easy in 2d).
     // cretainly not the most efficient way to do it but it seems to work
 
-    // but it doesn't :-(
-    /*
-    for (i = 0; i < List_Nbr (v->Surfaces); i++)
-      {
-	List_Read (v->Surfaces, i, &ss);
-	Tree_Action(ss->Simplexes, Free_Simplex);
-	Tree_Delete(ss->Simplexes);
-	ss->Simplexes = Tree_Create (sizeof (Simplex *), compareQuality);
-	Extrude_Mesh(ss);
-      }
-    */
+    // j'ai rajoute un truc assez horrible pour ne pas supprimer les
+    // tri/qua qui ne doivent pas l'etre, i.e. tous ceux qui ne sont
+    // pas crees par l'extrusion. Je les tagge avec un numero negatif
+    // (qu'ils garderont si on ne maille pas en 3d...).
+
+    for (i = 0; i < List_Nbr (v->Surfaces); i++){
+      List_Read (v->Surfaces, i, &ss);
+      tmp = Tree_Create (sizeof (Simplex *), compareQuality);
+      Tree_Action(ss->Simplexes, Free_NegativeSimplex);
+      Tree_Delete(ss->Simplexes);
+      ss->Simplexes = tmp;
+      Extrude_Mesh(ss);
+    }
+
+    for (i = 0; i < List_Nbr (v->Surfaces); i++){
+      List_Read (v->Surfaces, i, &ss);
+      Tree_Action(ss->Simplexes, Untag_NegativeSimplex);
+    }
 
     return true;
   }