Render glitch

[bigben]

This has been driving me nuts for the past month as I first thought it was something that I had done wrong.

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I first thought I screwed up the distribution of one of the snow sublayers resulting in these white peaks, although it didn't quite make sense.  It happened with both Lucio's embossed snow and cbalaskas' ice and snow.

I finally scrapped everything and started from scratch with just a powder snow layer using fake stones.
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...and this time it extends beyond the snow onto a piece of terrain with no additional shaders.

I've disabled just about everything after this (fill lights, shaders with translucency/transparency, GI, fractal detail ON or OFF) and it's still there so it seems to be terrain related.

TGD with TER: http://www.path.unimelb.edu.au/~bernardk/tgdemo/lighting_problem.zip (5.3Mb)

[helentr]

I tried your files and the problem seems to disappear if you uncheck ray traced shadows in the render tab (both quick and full render). As to what causes it, I have no idea ...

Helen

[bigben]

Many thanks Helen. This is a huge relief 

[rcallicotte]

That's interesting.  I discovered a problem with Ray Traced Shadows, too.

[Oshyan]

Hi Ben, we're looking into this issue. If there is indeed a bug here it will be resolved.

- Oshyan

[bigben]

I just had this happen again in my Ben Nevis image. The only change I made to the file was adding some nodes to add displacement to the terrain so there may be a possible link here. There were some displacements already in the snow but the scale of these are relatively small.

I'll keep a copy of the before and after files for later testing to see if I can narrow it down further.

[Volker Harun]

I had this one,too. I had to raise the clouds very very high to get rid of this issue - in my case it was an intersection of clouds with terrain, where no clouds were.