Page 1 of 1

32 Bit Texture clamped in Emission Channel

Posted: Tue Sep 10, 2019 8:28 am
by Yader
With some of my 32Bit Textures there's a difference in the render between CPU and GPU Mode. It looks like the 32Bit Texture gets clamped. See attached image. Is there a specific way my 32Bit Textures have to be set up, so they work the same in both modes?

Re: 32 Bit Texture clamped in Emission Channel

Posted: Tue Sep 10, 2019 10:02 am
by Zom-B
a great example for the terminator artifact issue.
Please have a ultra high subdivided sphere, instead of this "low poly" one and also give the CPU more time, that should "fix" this issue.

Re: 32 Bit Texture clamped in Emission Channel

Posted: Tue Sep 10, 2019 10:04 am
by Yader
So my CPU render will get darker over time? This was just for demonstration purposes, the content of the scene isn't just a sphere...

Re: 32 Bit Texture clamped in Emission Channel

Posted: Thu Sep 12, 2019 8:47 pm
by Zom-B
best to upload the pigs, so the devs have a testscene :)

Re: 32 Bit Texture clamped in Emission Channel

Posted: Mon Sep 16, 2019 3:40 am
by Yader
Here's the scene as a .pigs file aswell as a C4D scene.
The clamping is very much visible if you look at the light while turning GPU rendering on and off.
Thanks in advance.
https://www.dropbox.com/s/7usvgqrfji17x ... g.zip?dl=0

Re: 32 Bit Texture clamped in Emission Channel

Posted: Mon Sep 16, 2019 11:40 pm
by Zom-B
Hey Yader,

thanks a lot for your testscene!

Tested and reproduced your issue. Talked to the devs and it seems this is a "known limitation" that for GPU rendering 32bit emitters (all but EnvMap) get converted to 8bit at the moment, will be fixed in the future...

Re: 32 Bit Texture clamped in Emission Channel

Posted: Tue Sep 17, 2019 7:47 am
by Yader
Hey Zom-B,

thanks for testing, confirming and talking to the devs. I really do hope that this gets fixed as soon as possible :)