Perspective shadow maps

I’m working in a opengl application and we use shadow maps to generate shadows. Because of the aliasing, we are trying to add a variation, the Perspective Shadow Maps, as shown in this paper:*
But i think that’s a teoric approach, so i want to know if there’s a sample code, or someone has made a succesfully implementation of the algorithm and can explain me how exactly the post-perspective projection of the light shadow map is done.
Thanks in advance

There’s a presentation from GDC at that talks about how to do stable perspective shadow mapping in real applications.
Maybe that helps.



I’d suggest you take a look at this:

It’s not psm, but it’s a similar technique, and according to the author, a more robust one. I don’t know about that, but I’ve recently implemented it, and I’m quite satisfied about the results. The shadow resolution is ok and it makes great use of shadowmap precision. It was also quite easy to implement.