Kallikanzarid

I noticed on screenshots that you don't have a lighting system in place yet, so I thought I'd make suggestions. SSAO and SSDO are normally used in the post-processing stage to approximate indirect lighting effects, but there is no reason it can't work with prerendered backgrounds and sprites, as long as you include depth information and specify where the light sources are. You could use that to correctly light sprites or 3D models. Or you could go even further, leveraging frameworks like NVidia OptiX to raytrace indirect lighting on 3D models (or sprites with the depth information by first regenerating a part of their mesh). Modern GPUs can handle small scenes, and having prebaked backgrounds will simplify the task considerably. You could then draw approximate shadows on the backgrounds using cheaper techniques like SSDO. Or you could try something more bold, like raytracing the whole background scene and storing all rays so that you could then recast just a small portion of them intersected by the dynamic models and thus obtain a very good approximation to what you would see if you raytraced the whole thing dynamically. Not sure if GPUs can easily handle such a process, though.