After realizing the benefits of stencil shadow volumes for handling point-light shadows, I have been determined to add them to my own graphics engine. Days have turned into weeks and weeks into months. I can easily cast beautiful, clean shadows behind an occluder; but the self shadowing always suffers from ugly artifacts.
I thought I'd found my solution to cast smooth silhouette edges here, but issues involving z-fighting and the per-polygon nature of these calculations always ensure self-shadowing issues crop up. Countless tweaks and special case handling haven't gotten me out of the woods.
Even if I can get this working, I have more concerns. How well will GPU tessellation and displacement mapping work with stencil shadow volumes? Can I realistically expect to get the smoothness of shadow maps with these per-polygon calculations?
Moreover, all the literature I find on stencil shadow volumes seems to be at least 6 years old.. and it has me wondering are they just not practical anymore?
The only possibility I can see is if you used a hybrid: shadow-maps to handle self shadowing, and projected stencil shadow volumes elsewhere. But I wonder if you might as well go for all-shadow maps in that case.
If there are any proponents of stencil shadow volumes here, I'd love to know how you handle these concerns because if I switch to only shadow maps, I'll have to throw away a lot of work!