I want to create a game environment that supports a 2D map. This is a really basic map, but must be split along lines that are not necessarily straight. So imagine a country with county boundaries. I then want to be able to detect drag / drop events within these counties.
What I'm really looking for here is a pointer to where to start on this (how it has been done before - any existing libraries out there), as I'm sure that what I'm trying to do is not new - although I can't find a beginners guide for this anywhere.