I want to change the colors of the map, either to harsh black and white or some sort of inverted color or some similar effect.
I don't have the slightest idea of how that might be accomplished. My instinct is that it isn't possible with the current version of solarus...
I didn't see any functions that dealt directly with tilesets, and I don't think maps are drawn as Drawables that can be altered using blend modes...
I'm asking as a sort of last resort, does anyone have any ideas how I might change the look of the map in real time? (the whole map at once)
It is possible with the development version, with shaders. Today I think that Chris will stream a new development video about shaders, and I recommend you to watch the last one too, because he explains and shows many things.
I actually missed it while I was reading, but if I make a duplicate of each tileset, with the specific graphical alterations I need, there IS a function to swap tilesets while the map is loaded.
map:set_tileset(tileset_id)
It'll mean duplicating all my tilesets, but it'll work in lieu of waiting around for shaders...which I may not even figure out how to use.
I am not sure, but maybe shaders are already functional in the development version of the engine. Chris can tell you that. I don't know if that is included in the last snapshots.
In my opinion, duplicating all tilesets and sprites is too crazy and bad. Don't do it in that way. Wait 2-3 months until shaders are finished and do it with clean code.