What to do with alpha blending?

[mickey]

Seems like many people have been implementing their own support for per-pixel alpha blending, long-wanted in PF.
What operations with alpha-aware surfaces did you have to add, besides Blit? How did it affect the underlying design (surface format, etc) ?

What about the ability to blit one alpha-aware surface to another alpha-aware surface - and get alpha-aware results? It could be useful for pre-rendering composite pictures like a super-hero carrying a pile of weapons he's collected so far ( imagine )

Thanks