Tile Selection via mouse

I currently need a solution to the following:



I have a isometric mape of tiles that when i select a tile I would like to highlight the tile with a frame around the border of the tile. My first thought is I could have two textures one highlighted and then the normal and then just update the texture. I don’t necessarily want to have two different textures for one tile though. I was thinking if there was a way to overlay a frame on top of the tile that might be better.



Any suggestions?





Bonus question:



I use nifty gui to overlay a HUD/Frame ontop of my screen. I setup in full screen. When I click my map I want only the tile visible within the frame to be selectable. This is currently not the case as I can select tile that exist behind my frame and they will be activated.



Any solutions to the following questions will be appreciated.



Thanks,

Put invisible but visible-to-mouse panels on your nifty screen to mask out the areas you don’t want clickable.