It was very hard to discern which tiles were walls and which tiles where not walls.
Viewing post in Calefaction jam comments
I had a few ideas to resolve that, all of which would have required more work than I had time for during the jam. First, re-doing the pixel art to have consistent, stronger contrast between the floor and walls. Second, a shadow-cast effect with the wall tiles, likely using another shader. Third, layered tilemaps, so that walls do not have to use an entire tile and instead are overlayed above the floor tiles, to make the difference more defined. I’ll be testing all of these for later versions, alongside reducing the strength of some other visual effects, as together they can cause eye-strain.