PhotonGI cash problem

Use this forum for general user support and related questions.
Forum rules
Please upload a testscene that allows developers to reproduce the problem, and attach some images.
PetrT
Posts: 68
Joined: Sun Dec 02, 2018 6:13 pm
Location: Russia
Contact:

Re: PhotonGI cash problem

Post by PetrT » Mon Aug 30, 2021 3:54 pm

kintuX wrote:
Sat Aug 28, 2021 7:24 pm
Use of PhotonGI Cache makes results a bit darker.
Not sure, but I think it was already mentioned...
This topic about another problem.
Problem with shading solves when Environment Light Cache is turned off

kintuX
Posts: 707
Joined: Wed Jan 10, 2018 2:37 am

Re: PhotonGI cash problem

Post by kintuX » Mon Aug 30, 2021 8:29 pm

Righty then... not a problem really :D

PetrT
Posts: 68
Joined: Sun Dec 02, 2018 6:13 pm
Location: Russia
Contact:

Re: PhotonGI cash problem

Post by PetrT » Tue Aug 31, 2021 7:15 am

pic of test
Attachments
004.jpg

User avatar
Dade
Developer
Posts: 5523
Joined: Mon Dec 04, 2017 8:36 pm
Location: Italy

Re: PhotonGI cash problem

Post by Dade » Thu Sep 02, 2021 12:29 pm

PetrT wrote:
Sat Aug 28, 2021 7:24 am
Test scene https://dropmefiles.com/lJ5Za
I'm looking into the problem.
Support LuxCoreRender project with salts and bounties

User avatar
Dade
Developer
Posts: 5523
Joined: Mon Dec 04, 2017 8:36 pm
Location: Italy

Re: PhotonGI cash problem

Post by Dade » Fri Sep 03, 2021 11:36 am

It looks like the problem is related to the use of constant infinite light, if I replace the light source with an HDR infinite light source, it works fine:

hdr.jpg
Support LuxCoreRender project with salts and bounties

PetrT
Posts: 68
Joined: Sun Dec 02, 2018 6:13 pm
Location: Russia
Contact:

Re: PhotonGI cash problem

Post by PetrT » Fri Sep 03, 2021 3:34 pm

thank you

User avatar
Dade
Developer
Posts: 5523
Joined: Mon Dec 04, 2017 8:36 pm
Location: Italy

Re: PhotonGI cash problem

Post by Dade » Mon Sep 06, 2021 12:50 pm

Fu*k, this scene was driving me crazy, I was getting out all kind non sense results.

Your problem is just caused by an extremely low clamping value. If you disable variance clamping (or raise the value by a significative amount). The rendering will be fine.

You were "clamping" a tons of light, this is a rendering with your clamping value:

clamp.jpg

and this without clamping:

noclamp.jpg

You are clearing cutting half of the transported light (and causing artifacts in the process).
Support LuxCoreRender project with salts and bounties

User avatar
Sharlybg
Donor
Posts: 2907
Joined: Mon Dec 04, 2017 10:11 pm
Location: Ivory Coast

Re: PhotonGI cash problem

Post by Sharlybg » Mon Sep 06, 2021 5:05 pm

Fu*k, this scene was driving me crazy, I was getting out all kind non sense results.
As a reminder this should be put in the tooltips of clamping. ""Too low value can break lighting and create artifacts with GI cache """
Support LuxCoreRender project with salts and bounties

Portfolio : https://www.behance.net/DRAVIA

PetrT
Posts: 68
Joined: Sun Dec 02, 2018 6:13 pm
Location: Russia
Contact:

Re: PhotonGI cash problem

Post by PetrT » Mon Sep 06, 2021 10:08 pm

Dade wrote:
Mon Sep 06, 2021 12:50 pm
this scene was driving me crazy, I was getting out all kind non sense results.
Sorry,It was not the aim of my post.
I guess just another interesting case
004.png

User avatar
Dade
Developer
Posts: 5523
Joined: Mon Dec 04, 2017 8:36 pm
Location: Italy

Re: PhotonGI cash problem

Post by Dade » Mon Sep 06, 2021 11:33 pm

PetrT wrote:
Mon Sep 06, 2021 10:08 pm
Sorry,It was not the aim of my post.
I guess just another interesting case
I'm not sure to understand the statement but I have the feeling you have to run the rendering without clamping to get a valid suggested value.
Support LuxCoreRender project with salts and bounties

Post Reply