Workaround uninitialized colors

FileOBJT_impl.hh

@@ -144,6 +144,15 @@ Material& FileOBJPlugin::getMaterial(MeshT& _mesh, const OpenMesh::FaceHandle& _
 
     OpenMesh::Vec4f c = _mesh.color( _fh );
 
+    // If one of the entries is out of range, assume uninitialized color and set to default
+    // Ugly hack to ensure that materials will only be generated if initialized
+    if ( c[0] > 255.0 || c[1] > 255.0 || c[2] > 255.0 || c[0] < 0.0 || c[1] < 0.0 || c[2] < 0.0) {
+      c[0] = 155.0;
+      c[1] = 155.0;
+      c[2] = 155.0;
+      c[3] = 1.0;
+    }
+
     // First off, try to fetch texture index of current face/object...
     if(!textureIndexPropFetched_) {
         emit textureIndexPropertyName(_objId, textureIndexPropertyName_);
@@ -321,8 +330,8 @@ bool FileOBJPlugin::writeMesh(std::ostream& _out, QString _filename, MeshT& _mes
   // If mesh has halfedge tex coords, write them out instead of vertex texcoords
   if(optionVertexTexCoords && _mesh.has_halfedge_texcoords2D()) {
       int count = 1;
-      for (f_it = _mesh.faces_begin(); f_it != _mesh.faces_end(); ++f_it) {
-          for(fh_it=_mesh.fh_iter(*f_it); fh_it.is_valid(); ++fh_it) {
+      for ( auto f_it : _mesh.faces() ) {
+          for(fh_it=_mesh.fh_iter(f_it); fh_it.is_valid(); ++fh_it) {
               typename MeshT::TexCoord2D t = _mesh.texcoord2D(*fh_it);
               _out << "vt " << t[0] << " " << t[1] << '\n';
               vtMap.insert(std::pair<typename MeshT::HalfedgeHandle, int>(*fh_it, count));
@@ -333,19 +342,19 @@ bool FileOBJPlugin::writeMesh(std::ostream& _out, QString _filename, MeshT& _mes
 
   Material lastMat;
 
-  // we do not want to write seperators if we only write vertex indices
+  // we do not want to write separators if we only write vertex indices
   bool vertexOnly =     !(optionVertexTexCoords && _mesh.has_halfedge_texcoords2D())
                     &&  !(optionVertexTexCoords && !_mesh.has_halfedge_texcoords2D() && _mesh.has_vertex_texcoords2D())
                     &&  !(optionVertexNormals);
 
-  for (f_it = _mesh.faces_begin(); f_it != _mesh.faces_end(); ++f_it){
+  for ( auto f_it : _mesh.faces() ){
 
     if (useMaterial && optionFaceColors) {
 
-        Material& material = getMaterial(_mesh, *f_it, _objId);
+        Material& material = getMaterial(_mesh, f_it, _objId);
 
         // If we are ina a new material block, specify in the file which material to use
-        if(lastMat != material) {
+        if(lastMat.material_number() != material.material_number() ) {
             _out << "usemtl " << material << '\n';
             lastMat = material;
         }
@@ -354,7 +363,7 @@ bool FileOBJPlugin::writeMesh(std::ostream& _out, QString _filename, MeshT& _mes
     _out << "f";
 
     // Write out face information
-    for(fh_it=_mesh.fh_iter(*f_it); fh_it.is_valid(); ++fh_it) {
+    for(fh_it=_mesh.fh_iter(f_it); fh_it.is_valid(); ++fh_it) {
 
         // Write vertex index
         idx = _mesh.to_vertex_handle(*fh_it).idx() + 1;