Only if it is glossy and I asked before (posting.php?mode=quote&f=4&p=8053#pr7607) to redo the test with mate material so I assume the above rendering is showing a different problem
Direct Light cache: how to avoid splotches?
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Please upload a testscene that allows developers to reproduce the problem, and attach some images.
Please upload a testscene that allows developers to reproduce the problem, and attach some images.
Re: Direct Light cache: how to avoid splotches?
Re: Direct Light cache: how to avoid splotches?
Well there's also the other issue which looks a lot like this one, when you use heavy clamping.. Remember? I think it's always the same thing going on, just very visible with heavy clamping and/or very rough reflections + multiple light sources.Dade wrote: ↑Mon Dec 03, 2018 4:09 pmOnly if it is glossy and I asked before (posting.php?mode=quote&f=4&p=8053#pr7607) to redo the test with mate material so I assume the above rendering is showing a different problem
Re: Direct Light cache: how to avoid splotches?
And what's up with the spot made of bright pixels here? Related?
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Re: Direct Light cache: how to avoid splotches?
I sent you a PM with the scene.Dade wrote: ↑Mon Dec 03, 2018 4:09 pmOnly if it is glossy and I asked before (posting.php?mode=quote&f=4&p=8053#pr7607) to redo the test with mate material so I assume the above rendering is showing a different problem
About the carpet on the floor I confirm I used a matte material
Re: Direct Light cache: how to avoid splotches?
The first step when checking a DLSC related problem is always to switch max. path depth to 1 so you will see only direct light sampling:
It becomes quite evident that at glancing angles the information of the cache are not correct due to "normal threshold" (10 degrees in this case). If you lower the normal angle threshold to 4 degrees (and increase the radius to 15cm just to speed up the pre-processing):
and with full path depth:
Re: Direct Light cache: how to avoid splotches?
Thanks, going to check but I have the strong feeling the problem is in the impossibility to have reliable cache information over the carpet (the particle system for hair simulating the carpet will likely to generate a surface over which is impossible to interpolate correct information).
Re: Direct Light cache: how to avoid splotches?
Some exclude list or something else to help the engine with samples estimation?
Could be helpful in this case?
Could be helpful in this case?
Re: Direct Light cache: how to avoid splotches?
Or maybe retracing problematic areas if they can be identified...?
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Re: Direct Light cache: how to avoid splotches?
Wow! This is a good step by step instruction for DLSC related issues. Thank you much, Dade.Dade wrote: ↑Tue Dec 04, 2018 11:08 amThe first step when checking a DLSC related problem is always to switch max. path depth to 1 so you will see only direct light sampling:
prob1.jpg
It becomes quite evident that at glancing angles the information of the cache are not correct due to "normal threshold" (10 degrees in this case). If you lower the normal angle threshold to 4 degrees (and increase the radius to 15cm just to speed up the pre-processing):
fix1.jpg
and with full path depth:
fix2.jpg
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Re: Direct Light cache: how to avoid splotches?
If I remember correctly, vray has this retracing threshold value for Light caching, I guess it's a workaround to deal with these type of problematic areas...? If we could detect shadow borders and these areas where cache has problems, maybe we could force "retracing" those areas, replacig cache with brute force?