message: Return early in contour fitting if given image_edges is empty
diff: @@ -354,6 +354,12 @@ find_occluding_edge_correspondences(const core::Mesh& mesh, const morphablemodel
  using Eigen::Vector2f;
  using std::vector;
  + // If there are no image_edges given, there's no point in computing anything:
  + if (image_edges.empty())
  + {
  + return {};
  + }
  +
  // Compute vertices that lye on occluding boundaries:
  const auto occluding_vertices =
  occluding_boundary_vertices(mesh, edge_topology, glm::mat4x4(rendering_parameters.get_rotation()));
  