XYWindow background can't be loaded if image is not in format supported by the game (ref #141), neither if outside the VFS
The XYWindow background image is loaded using
QERApp_LoadImage which loads file from the VFS, ignoring all the formats that are not explicitly listed in
Because of this:
- a PNG XYWindow image can't be loaded if the game only supports TGA (similar to #141).
- a PNG XYWindow image can't be loaded from arbitrary directories like the user home directory.
In both case, I don't think so much restrictions makes sense. There can be legit uses case where the XYWindow background image is part of the mapper's workflow but does not have to be included in to-be-released game assets.