I've noticed this behavior when rendering using path+opencl
It was discussed in some threads somewhat before. Long triangles are rendering dark. However on cpu it's not a problem, why is that?
Also raising min epsilon helps a bit but in my example rough glass is somewhat darker anyways. And in other cases with some cad files backfaces render dark/not black using gpu but on cpu it's ok.
Which can be pretty annoying when everything looks ok and then I switch to cpu+gpu and suddenly all kinds of artifacts appear. Is this something that can be fixed?
Attached also a primitive example scene(just use any hdri with it)
shading errors on opencl
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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.
shading errors on opencl
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- shadingerror.blend
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Re: shading errors on opencl
rough glass, cpu+gpu vs gpu only. 20 sec. rendering
Re: shading errors on opencl
put minimum epsilon value to 0.0001 instead of 0.00001 :
Re: shading errors on opencl
maybe for better illustration, cpu vs gpu roughglass.
cpu roughglass is also extremely slow to compute.
cpu roughglass is also extremely slow to compute.
Re: shading errors on opencl
I've mentioned this in my first post..
This doesn't help always, and it makes problem less visible not gone completely in other cases(and problem is not visible on cpu only). Also, rough glass is rendering differently with gpu than on cpu.