I'm currently working on a few tech demos to see how I can make a 2d tiled world look impressive. I've started with using Dot3 bump mapping to simulate lighting on a tile map.
At the moment the light fades linearly over a fixed distance but I can easilly work out more intersting way for the lights to operate, like giving them radiuses and attentuation factors. The one thing I wasn't able to do with the dot3 bump mapping was colored lighting because my graphics card didn't support D3DPMISCCAPS_PERSTAGECONSTANT and I was already using the texture factor render state to store the light vector. I could easilly do the colored lighting by writing a simple shader but I would like to keep this in the fixed function pipeline for as long as possible. Its a 2d game and really has no excuse not to work on most medium-end hardware.
I want to see how soft shaddow volumes look on top of this. I hadn't really been expecting to do any of the shading through the bump mapping but when I tried it out it looked surprisingly well. I'm going to have to write a second test app to see what soft shaddows ontop of plain bump mapping looks like compared to this.