So I am preparing to create my own map editor for an XNA game I will be working on. The map editor will need the ability to import graphic sprite sheets, allow me to pick various tiles on those sprite sheets and plot them on a virtual game map. It will also need auto tiling and perhaps even other features later on. Upon saving the map the editor will transform the tile ID's, map layer ID's and sprite sheet file data into a single .map file.

I don't want to embed XNA in a forms project, but I do want to be able to run my map in XNA by use of a play button on the editor interface, to test the map in XNA.

Herein lies the problem, I am not sure where to start. Should I go with WPF? Or maybe forms and create a series of custom controls? Or perhaps a forms project where I go batty with GDI+? Or perhaps some other route for the editor. I need an outside the box opinion here.

P.S. - I know these types of editors already exist, some for free and others to purchase. However, I want to create a proprietary one that will be used for games created by my studio going forward. Thus I am not interested in trying or buying any pre-made editors.

Thanks in advance!

Is there any particular reason why you don't want to embed XNA in your WinForm? There are tutorials for doing so and I think if you are building an editor for an XNA game that you would want to see rendering that was as close to possible as what you would be seeing in game.

Alternatively you could use MonoGame or SlimDX. GDI+ could potentially be used on top of one of these options.