Code review comment for lp:~widelands-dev/widelands/full_texture_atlas

I like the idea of adding a special loading screen when Widelands is first run - e.g. the text could read "Optimizing Widelands images for first usage" or some such, so the user will know that they won't have to wait for this in the future.

We should then build the texture atlas only for the current resolution + fullscreen mode - the other resolutions could be calculated when the user switches the resolution, with a similar loading screen.