I finally got around to giving the Athene model a combined normal mapping and depth-shadowmapping shader - you might have noticed I’d avoided doing any close-ups of it in previous shots, it’s because it I hadn’t gotten around to it yet and Athene was still using the old normal mapping shader. As you can see she self-shadows nicely now and the shadow detail nicely follows the normal mapped detail like the folds in her cloak. These shots were taken with LiSPSM projection and a 5-tap percentage closest filter.
I’ve also implemented the GLSL versions of the shaders and it’s working fine in GL now. Strangely I found I had to revert to half-float textures in GL since full-float was not only pig-slow, the texture alignment appeared to be completely off. Not sure why currently, but the half-float version works ok in GL given the right bias values and is quite quick on my relatively lowly 6800 GS.
Next on my list is turning those bias tweak boxes into sliders so people can play with them, not only will it allow people to experiment but it will also clearly indicate to potential users that tweaking the appropriate bias for your projection basis / rendersystem / scene setup is very important with this approach, and maybe they won’t post in the forums quite so often complaining of shimmering shadows when using default settings ;).