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I'm using irrlicht for linux and there seems to be a problem with lighting. If I enable shadows there's also a bug with the screen flashing blended with black too.
I'm using the ati drivers.
That is, I remember that the techdemo used lighting, right? Anyway; if it does not, then there's still the shadow bug.
The problem is that I was not able to check out the shaders under linux until now, because the last time I tried to install drivers for my ATI hardware, they corrupted my system. But I'll try again.