[Bug 31830] [bisected] broken shadows in Unigine Sanctuary and Lightsmark

https://bugs.freedesktop.org/show_bug.cgi?id=31830

--- Comment #12 from Marek Olšák maraeo@gmail.com 2011-01-27 02:20:19 PST --- Well, if I disable the register rename pass, the Penumbra shadows are rendered more or less correctly, so it must be a bug somewhere in the pair passes (or maybe even rename_regs).

My hypothesis is that a few unitialized shadow-map coordinates shouldn't influence the results computed from other shadow maps and those undefined shadow map samples should not contribute much to the final color, considering that the majority of samples are still computed correctly.

Also, disabling rename_regs speeds up Lightsmark by about 50%, so we should really reconsider whether having such a pass is worth the cost.