08.04.2012, 09:59
You need only save two coordinates, two opposite corners.
Save the top-right (north-east) corner and the bottom-left (south-west) corners.
North-east will be maxy and maxx, and the south-west corner will be minx and miny.
Save the top-right (north-east) corner and the bottom-left (south-west) corners.
North-east will be maxy and maxx, and the south-west corner will be minx and miny.