Am 12.02.2011 20:10, schrieb Stephen:
> I rendered a scene with SSLT but forgot to add #version 3.7 to the
> scene. It rendered fine with little difference between them, just noise
> on the Mesh. There was no warning about the version, should there be?

As a general rule-of-thumb, the #version setting only affects /changed/ 
features (that would otherwise break backward compatibility), not new ones.

> I re-rendered the #version 3.7 again and there are differences on all
> the images as if I was using crand. Does it matter which noise generator
> you use. I was using Perlin.

No, the Perlin-alike-noise generator used for patterns (e.g. bozo) and 
turbulence (which is always Perlin-alike) has nothing to do with it; 
SSLT doesn't need a 3D random pattern - just a stream of pseudo-random 
numbers and vectors.

The difference in the noise is simply due to differences in the order in 
which pixels are rendered. In POV-Ray 3.6 that's line-by-line, and in 
POV-Ray 3.7 it's block-by-block (with the order of blocks being somewhat 
arbitrary due to the use of multiple parallel threads, making results 
differ even from render to render).

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