message: Generate enough dummy tex_coords
  We need three tex_coords per triangle, not only one!
diff: @@ -541,7 +541,7 @@ void load_obj(std::vector<std::string> const& filenames, model& mod)
  }
  // See that each triangle has (potentially dummy) texture coordinates
  - for (size_t i = mod.tex_coords.size(); i < mod.primitives.size(); ++i)
  + for (size_t i = mod.tex_coords.size(); i < mod.primitives.size() * 3; ++i)
  {
  mod.tex_coords.emplace_back(0.0f);
  mod.tex_coords.emplace_back(0.0f);
  