From 2239cbd7470abfb3840008a97927a912438b9da6 Mon Sep 17 00:00:00 2001
From: cignoni <paolo.cignoni@isti.cnr.it>
Date: Wed, 11 May 2011 10:04:33 +0000
Subject: [PATCH] added simple boundary capper. Takes a edge mesh and caps its
 boundaries.

---
 wrap/gl/glu_tessellator_cap.h | 72 +++++++++++++++++++++++++++++++++++
 1 file changed, 72 insertions(+)
 create mode 100644 wrap/gl/glu_tessellator_cap.h

diff --git a/wrap/gl/glu_tessellator_cap.h b/wrap/gl/glu_tessellator_cap.h
new file mode 100644
index 00000000..3675e377
--- /dev/null
+++ b/wrap/gl/glu_tessellator_cap.h
@@ -0,0 +1,72 @@
+#ifndef GLU_TESSELLATOR_CAP_H
+#define GLU_TESSELLATOR_CAP_H
+#include "glu_tesselator.h"
+
+namespace vcg {
+namespace tri {
+
+// This function take a mesh with one or more boundary stored as edges, and fill another mesh with a triangulation of that boundaries.
+// it assumes that boundary are planar and exploits glutessellator for the triangulaiton
+template <class MeshType>
+void CapEdgeMesh(MeshType &em, MeshType &cm)
+{
+  typedef typename MeshType::EdgeType EdgeType;
+  std::vector< std::vector<Point3f> > outlines;
+  std::vector<Point3f> outline;
+  UpdateFlags<MeshType>::EdgeClearV(em);
+  UpdateTopology<MeshType>::EdgeEdge(em);
+  int nv=0;
+  for(size_t i=0;i<em.edge.size();i++)
+  {
+    if (!em.edge[i].IsV())
+    {
+      EdgeType* startE=&(em.edge[i]);
+      int startI = 0;
+      int curI = startI;
+      EdgeType* curE = startE;
+      EdgeType* nextE; int nextI;
+      do
+      {
+        curE->SetV();
+        outline.push_back(curE->V(curI)->P());
+        nextE=curE->EEp((curI+1)%2);
+        nextI=curE->EEi((curI+1)%2);
+        curE=nextE;
+        curI=nextI;
+        nv++;
+      }
+      while(curE != startE);
+
+      outlines.push_back(outline);
+      outline.clear();
+    }
+  }
+  if (nv<2) return;
+//  printf("Found %i outlines for a total of %i vertices",outlines.size(),nv);
+
+  typename MeshType::VertexIterator vi=vcg::tri::Allocator<MeshType>::AddVertices(cm,nv);
+  for (size_t i=0;i<outlines.size();i++)
+  {
+    for(size_t j=0;j<outlines[i].size();++j,++vi)
+      (&*vi)->P()=outlines[i][j];
+  }
+
+  std::vector<int> indices;
+  glu_tesselator::tesselate(outlines, indices);
+  std::vector<Point3f> points;
+  glu_tesselator::unroll(outlines, points);
+  typename MeshType::FaceIterator fi=tri::Allocator<MeshType>::AddFaces(cm,nv-2);
+  for (size_t i=0; i<indices.size(); i+=3,++fi)
+  {
+    (*&fi)->V(0)=&cm.vert[ indices[i+0] ];
+    (*&fi)->V(1)=&cm.vert[ indices[i+1] ];
+    (*&fi)->V(2)=&cm.vert[ indices[i+2] ];
+  }
+  Clean<MeshType>::RemoveDuplicateVertex(cm);
+  UpdateBounding<MeshType>::Box(cm);
+}
+
+} // end namespace tri
+} // end namespace vcg
+
+#endif // GLU_TESSELLATOR_CAP_H