- read_mesh now throws a compile error if an Options::Flag enum is passed as an argument instead of an Options object

- added a unit test for writing and reading vertex colors to and from an OFF file. The default color type Vec3uc from DefaultTraits in Traits.hh is used.

refs #1404

git-svn-id: http://www.openmesh.org/svnrepo/OpenMesh/trunk@809 fdac6126-5c0c-442c-9429-916003d36597

src/OpenMesh/Core/IO/MeshIO.hh

@@ -89,19 +89,16 @@ namespace IO   {
 
     @param _mesh     The target mesh that will be filled with the read data
     @param _filename fill to load
-    @param _clear    Clear the target data before filling it (allows to
-                     load multiple files into one Mesh)
 
     @return Successful?
  */
 template <class Mesh>
 bool
 read_mesh(Mesh&         _mesh,
-	  const std::string&  _filename,
+	  const std::string&  _filename)
-	  bool                _clear = true)
 {
   Options opt;
-  return read_mesh(_mesh, _filename, opt, _clear);
+  return read_mesh(_mesh, _filename, opt, true);
 }
 
 
@@ -116,9 +113,12 @@ read_mesh(Mesh&         _mesh,
     @param _mesh     The target mesh that will be filled with the read data
     @param _filename fill to load
     @param _opt      Reader options (e.g. skip loading of normals ... depends
-                     on the reader capabilities)
+                     on the reader capabilities). Note that simply passing an
+                     Options::Flag enum is not sufficient.
     @param _clear    Clear the target data before filling it (allows to
-                     load multiple files into one Mesh)
+                     load multiple files into one Mesh). If you only want to read a mesh
+                     without clearing set _clear to false. Providing a default Options
+                     object is sufficient in this case.
 
     @return Successful?
 */

src/Unittests/unittests_loading.hh

@@ -49,6 +49,51 @@ TEST_F(OpenMeshLoader, LoadSimpleOFFFile) {
 }
 
 
+TEST_F(OpenMeshLoader, WriteAndReadVertexColorsToAndFromOFFFile) {
+
+    mesh_.clear();
+
+    mesh_.request_vertex_colors();
+
+    mesh_.add_vertex( Mesh::Point(0,0,1) );
+    mesh_.add_vertex( Mesh::Point(0,1,0) );
+    mesh_.add_vertex( Mesh::Point(0,1,1) );
+    mesh_.add_vertex( Mesh::Point(1,0,1) );
+
+    // using the default color type Vec3uc from DefaultTraits in Traits.hh
+    Mesh::Color testColor(255, 128, 64);
+
+    // setting colors (different from black)
+    for (Mesh::VertexIter vit = mesh_.vertices_begin(), vitend = mesh_.vertices_end(); vit != vitend; ++vit)
+      mesh_.set_color(vit, testColor);
+
+    // check if the colors are correctly setted
+    int count = 0;
+    for (Mesh::VertexIter vit = mesh_.vertices_begin(), vitend = mesh_.vertices_end(); vit != vitend; ++vit) {
+      Mesh::Color color = mesh_.color(vit);
+      if ( color[0] != testColor[0] || color[1] != testColor[1] || color[2] != testColor[2] )
+        ++ count;
+    }
+
+    EXPECT_EQ(0, count) << "Vertices have the wrong color!";
+
+    // write the mesh_
+    OpenMesh::IO::Options opt(OpenMesh::IO::Options::VertexColor);
+    OpenMesh::IO::write_mesh(mesh_, "temp.off", opt);
+    OpenMesh::IO::read_mesh(mesh_, "temp.off", opt);
+
+    // check if vertices still have the same color
+    count = 0;
+    for (Mesh::VertexIter vit = mesh_.vertices_begin(), vitend = mesh_.vertices_end(); vit != vitend; ++vit) {
+      Mesh::Color color = mesh_.color(vit);
+      if ( color[0] != testColor[0] || color[1] != testColor[1] || color[2] != testColor[2] )
+        ++ count;
+    }
+
+    EXPECT_EQ(0, count) << "Vertices should have the same color after writing and reading the OFF file!";
+
+    mesh_.release_vertex_colors();
+}
 
 /*
  * Just load a simple mesh file in stla format and count whether