I may attempt some high dynamic range (
http://en.wikipedia.org/wiki/High_dynamic_range_rendering) effects with shader model 3.0 since Wikipedia says 32bit precision per component colour is guaranteed and it seems to be the highest shading model supported by Direct3D9.
The only immediate gain I can think of would be the possibility of white light overwhelming the texture... so if the lights were bright enough the texture would become whited out, which is not currently possible, as the brightest white under classic d3d/Som can only be as bright as the texture under non-additive lighting conditions (which is basically what Som uses)
I have seen Som go into an additive blending mode but I couldn't find anything in the scene (around Thedecks Keep's entrance in DD) that was actually being rendered??
Also in theory black (negative) lighting could be used for some weird effects. But I'm thinking without some indirect work around you'd have to offset the lighting for maps/lamps (so zero starts somewhere in the middle) and textures also if you wanted those black. Some black light magic spells might be be cool. I think for sure I'm going to do some texture recognition work after I can finish up with the light management stuff. Recognizing the textures is the only clean cut way I can think of to really correct for some stuff without breaking older games like Dom and DD and whatever new games keep using bad objects. Recognizing textures also will open the door to replace textures with better ones / additional effect layers like specular/dirt maps (which I think would add a lot for not a whole lot)
I've also seen some indicators that maybe .x files store parameters which map directly to DirectX. So it may be possible for mdo files at least to even extend what Som is currently capable of. Though not beyond what parameters Som actually applies. It might even be possible to use values which weren't defined in Som's day.
