optimization routines for 2d meshes

Mesh/meshGFaceOptimize.cpp

+#include "meshGFaceOptimize.h"
+#include "GFace.h"
+#include "GEdge.h"
+#include "GVertex.h"
+#include "MVertex.h"
+#include "MElement.h"
+#include <map>
+#include <vector>
+
+typedef std::map<MVertex*,std::vector<MTriangle*> > v2t_cont ;
+
+void buildVertexToTriangle ( GFace *gf ,  v2t_cont &adj )
+{
+  adj.clear();
+  for (unsigned int i=0;i<gf->triangles.size();i++)
+    {
+      MTriangle *t = gf->triangles[i];
+      for (unsigned int j=0;j<3;j++)
+	{
+	  MVertex *v = t->getVertex(j);
+	  v2t_cont :: iterator it = adj.find ( v );      
+	  if (it == adj.end())
+	    {
+	      std::vector<MTriangle*> one;
+	      one.push_back(t);
+	      adj[v] = one;
+	    }
+	  else
+	    {
+	      it->second.push_back(t);
+	    }
+	}
+    }
+}
+
+
+void parametricCoordinates ( MTriangle *t , GFace *gf, double u[3], double v[3])
+{
+  for (unsigned int j=0;j<3;j++)
+    {
+      MVertex *ver = t->getVertex(j);
+      GEntity *ge = ver->onWhat();
+      if (ge->dim() == 2)
+	{
+	  ver->getParameter ( 0,u[j]);
+	  ver->getParameter ( 1,v[j]);	  
+	}
+      else if (ge->dim() == 1)
+	{
+	  double t;
+	  ver->getParameter ( 0,t);
+	  GEdge *ged = dynamic_cast<GEdge*> (ge);
+	  SPoint2 p = ged->reparamOnFace ( gf , t , 1);
+	  u[j] =p.x(); 
+	  v[j] =p.y(); 
+	}
+      else
+	{
+	  GVertex *gver = dynamic_cast<GVertex*> (ge);
+	  SPoint2 p = gver->reparamOnFace ( gf , 1);
+	  u[j] =p.x(); 
+	  v[j] =p.y(); 
+	}      
+    }
+}
+
+void laplaceSmoothing (GFace *gf)
+{
+  v2t_cont adj;
+  buildVertexToTriangle ( gf ,  adj );
+
+  v2t_cont :: iterator it = adj.begin();
+  
+  while (it != adj.end())
+    {
+      MVertex *ver= it->first;
+      GEntity *ge = ver->onWhat();
+      // this vertex in internal to the face
+      if (ge->dim() == 2)
+	{
+	  double initu,initv;
+	  ver->getParameter ( 0,initu);
+	  ver->getParameter ( 1,initv);
+
+	  const std::vector<MTriangle*> & lt = it->second;
+
+	  double fact = lt.size() ? 1./(3.*lt.size()):0;
+
+	  double cu=0,cv=0;
+	  double pu[3],pv[3];
+	  for (unsigned int i=0;i<lt.size();i++)
+	    {
+	      parametricCoordinates ( lt[i] , gf, pu, pv);
+	      cu += fact*(pu[0]+pu[1]+pu[2]);
+	      cv += fact*(pv[0]+pv[1]+pv[2]);
+	      // have to test validity !
+	    }
+	  ver->setParameter(0,cu);
+	  ver->setParameter(1,cv);
+	  GPoint pt = gf->point(SPoint2(cu,cv));
+	  ver->x() = pt.x();
+	  ver->y() = pt.y();
+	  ver->z() = pt.z();
+	}
+    }
+  
+
+}
+
+