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wrong light groups with OpenCL

Posted: Mon Mar 04, 2019 10:22 pm
by pixel_peeper
Hi!

I'm working on a project and I'm facing a quite big issue for me: I need 6 light group (5 differnt groups and the default one) and if I render with CPU everything is ok, but if I switch to openCL the last group is also visibe in the the default group. Moreover some obejects (group instance) that have an emitter material are completely dark with OpenCL.

I'm doing an animation where 5 different emitter material changes their intensity and since it's impossible to insert keyframes in the material node graph, I'm usingh the light groups. But I can't take advantages of fast OpenCL because the default light grup will always show also the last one.

This bug can be fixed or can I use any workaround? Thanks!

I'm sorry if I can't be more clear but I'm quite new to LuxCore and this bug is quite complex...

some specs:
Win 10 with i7 8600K and GTX 1070 Ti
Path tracing, Metropolis, Power light strategy and calmping active

example file: https://ufile.io/mh340

Re: wrong light groups with OpenCL

Posted: Mon Mar 04, 2019 10:59 pm
by Dade
The number of light groups supported in OpenCL is capped to 8 (default+7): https://github.com/LuxCoreRender/LuxCor ... m.cpp#L119

So it should work in your case. Tomorrow, I will check what is going wrong.

Re: wrong light groups with OpenCL

Posted: Tue Mar 05, 2019 6:11 am
by Floke
I have the same problem but I found that happens only when clamp output is on, if I disable it all works fine.

Re: wrong light groups with OpenCL

Posted: Tue Mar 05, 2019 6:14 am
by Floke
On CPU clamps output with light groups work perfect

Re: wrong light groups with OpenCL

Posted: Tue Mar 05, 2019 6:44 am
by pixel_peeper
Floke wrote: Tue Mar 05, 2019 6:11 am I have the same problem but I found that happens only when clamp output is on, if I disable it all works fine.
Thanks! I'll give it a try, since my scene is very difficult (3000 light sources through tranlucent mat) clamping is not effective at all.

Re: wrong light groups with OpenCL

Posted: Tue Mar 05, 2019 9:37 am
by pixel_peeper
Ok, if I disable clamp everything works fine on the scene I uploaded in this thread. But with my project scene the strange behaviour of some emitter that remains dark or with fewer samples is still present.

Here there is a simplified version of my project scene, the fewer samples issue in some random instance could be seen more clearly in Col-R and Col-B Render Layer.

https://ufile.io/huo7v

If anyone has also any tip on how to reduce render time (and fireflies) is much appreciated :D

Re: wrong light groups with OpenCL

Posted: Tue Mar 05, 2019 10:42 am
by Dade
Dade wrote: Mon Mar 04, 2019 10:59 pm The number of light groups supported in OpenCL is capped to 8 (default+7): https://github.com/LuxCoreRender/LuxCor ... m.cpp#L119

So it should work in your case. Tomorrow, I will check what is going wrong.
I fixed the problem. It was a quite obvious cut&paste typo: https://github.com/LuxCoreRender/LuxCor ... 6b98a02d2e

You can use LuxCoreRender daily/automatic builds if you need the fix, it should be ready in a couple of hours: viewtopic.php?f=9&t=736

Re: wrong light groups with OpenCL

Posted: Tue Mar 05, 2019 1:57 pm
by pixel_peeper
Dade wrote: Tue Mar 05, 2019 10:42 am
Dade wrote: Mon Mar 04, 2019 10:59 pm The number of light groups supported in OpenCL is capped to 8 (default+7): https://github.com/LuxCoreRender/LuxCor ... m.cpp#L119

So it should work in your case. Tomorrow, I will check what is going wrong.
I fixed the problem. It was a quite obvious cut&paste typo: https://github.com/LuxCoreRender/LuxCor ... 6b98a02d2e

You can use LuxCoreRender daily/automatic builds if you need the fix, it should be ready in a couple of hours: viewtopic.php?f=9&t=736
unfortunately I get the same result with both file I've uploaded here. I downloaded the latest build frome here https://github.com/LuxCoreRender/LuxCor ... tag/latest and I copied all the files to this folder on my PC C:\Users\myusername\AppData\Roaming\Blender Foundation\Blender\2.79\scripts\addons\BlendLuxCore\bin

It is correct? what I'm doing wrong? Thank you so much!
pixel_peeper wrote: Tue Mar 05, 2019 9:37 am Ok, if I disable clamp everything works fine on the scene I uploaded in this thread. But with my project scene the strange behaviour of some emitter that remains dark or with fewer samples is still present.
Also this thing still happens, I don't know if it's a bug or my fault, sorry.

Re: wrong light groups with OpenCL

Posted: Tue Mar 05, 2019 3:19 pm
by Dade
pixel_peeper wrote: Tue Mar 05, 2019 1:57 pm unfortunately I get the same result with both file I've uploaded here. I downloaded the latest build frome here https://github.com/LuxCoreRender/LuxCor ... tag/latest and I copied all the files to this folder on my PC C:\Users\myusername\AppData\Roaming\Blender Foundation\Blender\2.79\scripts\addons\BlendLuxCore\bin
I have downloaded the binaries and tested them (on Linux), they seems to work fine. Check if you have really updated the right files.

Try to delete the C:\Users\myusername\AppData\Roaming\Blender Foundation\Blender\2.79\scripts\addons\BlendLuxCore\bin\pyluxcore.pyd file and to run Blender, if BlendLuxCore doesn't gives you an error, it means you are updating the wrong file.

Re: wrong light groups with OpenCL

Posted: Tue Mar 05, 2019 3:58 pm
by pixel_peeper
I have downloaded luxcorerender-latest-win64-opencl.zip but I still get the same result. If I remove pyluxcore.pyd I get the error as expected and if I restore the file LuxCore works, but always with that bug...