From b6d198362c370458128dd0cd97eb1edd611dfc86 Mon Sep 17 00:00:00 2001
From: cignoni <paolo.cignoni@isti.cnr.it>
Date: Wed, 31 Oct 2012 06:58:08 +0000
Subject: [PATCH] Small changes to the compactVector (added a check on empty
 vectors) and improved the sample on allocation.

---
 .../trimesh_allocate/trimesh_allocate.cpp     | 19 ++++++++-----------
 vcg/complex/allocate.h                        |  3 ++-
 2 files changed, 10 insertions(+), 12 deletions(-)

diff --git a/apps/sample/trimesh_allocate/trimesh_allocate.cpp b/apps/sample/trimesh_allocate/trimesh_allocate.cpp
index 63b1df0c..428cee49 100644
--- a/apps/sample/trimesh_allocate/trimesh_allocate.cpp
+++ b/apps/sample/trimesh_allocate/trimesh_allocate.cpp
@@ -46,19 +46,17 @@ class MyMesh : public vcg::tri::TriMesh< std::vector<MyVertex>, std::vector<MyFa
 int main()
 {
   MyMesh m;
-  vcg::tri::Allocator<MyMesh>::AddVertices(m,3);
-  vcg::tri::Allocator<MyMesh>::AddFaces(m,1);
+  MyMesh::VertexIterator vi = vcg::tri::Allocator<MyMesh>::AddVertices(m,3);
+  MyMesh::FaceIterator fi = vcg::tri::Allocator<MyMesh>::AddFaces(m,1);
 
   MyMesh::VertexPointer ivp[3];
-  MyMesh::VertexIterator vi=m.vert.begin();
-  ivp[0]=&*vi;(*vi).P()=MyMesh::CoordType ( 0.0, 0.0, 0.0); ++vi;
-  ivp[1]=&*vi;(*vi).P()=MyMesh::CoordType ( 1.0, 0.0, 0.0); ++vi;
-  ivp[2]=&*vi;(*vi).P()=MyMesh::CoordType ( 0.0, 1.0, 0.0); ++vi;
+  ivp[0]=&*vi; vi->P()=MyMesh::CoordType ( 0.0, 0.0, 0.0); ++vi;
+  ivp[1]=&*vi; vi->P()=MyMesh::CoordType ( 1.0, 0.0, 0.0); ++vi;
+  ivp[2]=&*vi; vi->P()=MyMesh::CoordType ( 0.0, 1.0, 0.0); ++vi;
 
-  MyFace &f=m.face[0];
-  f.V(0)=ivp[0];
-  f.V(1)=ivp[1];
-  f.V(2)=ivp[2];
+  fi->V(0)=ivp[0];
+  fi->V(1)=ivp[1];
+  fi->V(2)=ivp[2];
 
   // a potentially dangerous pointer to a mesh element
   MyMesh::FacePointer fp = &m.face[0];
@@ -77,7 +75,6 @@ int main()
   vcg::tri::Allocator<MyMesh>::DeleteFace(m,m.face[3]);
 
   // If you loop in a mesh with deleted elements you have to skip them!
-  MyMesh::FaceIterator fi;
   for(fi = m.face.begin(); fi!=m.face.end(); ++fi )
   {
      if(!fi->IsD()) //    <---- Check added
diff --git a/vcg/complex/allocate.h b/vcg/complex/allocate.h
index 2c5b9350..939efb25 100644
--- a/vcg/complex/allocate.h
+++ b/vcg/complex/allocate.h
@@ -609,7 +609,8 @@ public:
 		*/
 		static void PermutateVertexVector(MeshType &m, PointerUpdater<VertexPointer> &pu) 
 		{
-			for(unsigned int i=0;i<m.vert.size();++i)
+		  if(m.vert.empty()) return;
+		  for(unsigned int i=0;i<m.vert.size();++i)
 			{
 				if(pu.remap[i]<size_t(m.vn))
                 {