Light Groups (Noob)

Use this forum for general user support and related questions.
Post Reply
Gobo
Posts: 7
Joined: Fri Oct 25, 2019 2:12 pm

Light Groups (Noob)

Post by Gobo » Fri Oct 25, 2019 4:38 pm

Hello,

Is there any way to calculate the specific indirect components into a Light Group element?

Cheers,
Axel

User avatar
Dade
Developer
Developer
Posts: 3241
Joined: Mon Dec 04, 2017 8:36 pm
Location: Italy

Re: Light Groups (Noob)

Post by Dade » Fri Oct 25, 2019 5:22 pm

Gobo wrote:
Fri Oct 25, 2019 4:38 pm
Is there any way to calculate the specific indirect components into a Light Group element?
A light group always includes both Direct+Indirect: you have to render the image with only the light(s) you are interested and, at that point, you can use indirect light AOV.
Support LuxCoreRender project with salts and bounties

Gobo
Posts: 7
Joined: Fri Oct 25, 2019 2:12 pm

Re: Light Groups (Noob)

Post by Gobo » Mon Oct 28, 2019 4:08 pm

Then i am doing it wrong in Blender:

- Specify Light Groups in Blender View Layers
- Add lights to Groups
- The Light Groups appear as AOVs in the Compositor Render Layers
- Looking at one of them they are direct only

How can i approach it in a better way?

Thanks!

User avatar
B.Y.O.B.
Developer
Developer
Posts: 2997
Joined: Mon Dec 04, 2017 10:08 pm
Location: Germany
Contact:

Re: Light Groups (Noob)

Post by B.Y.O.B. » Mon Oct 28, 2019 10:21 pm

Can you show images?
Support LuxCoreRender project with salts and bounties

Gobo
Posts: 7
Joined: Fri Oct 25, 2019 2:12 pm

Re: Light Groups (Noob)

Post by Gobo » Tue Oct 29, 2019 8:07 am

01_original.png
Original render
02_lightgroup-channel.png
Lightgroup channel (Looks like direct only)
03_indir_hangs_on_default-channel.png
Default channel (Ha, indirect hangs around here - If i render all Lightgroups *all* indirects are mixed in here)

User avatar
Dade
Developer
Developer
Posts: 3241
Joined: Mon Dec 04, 2017 8:36 pm
Location: Italy

Re: Light Groups (Noob)

Post by Dade » Tue Oct 29, 2019 8:23 am

Ah, but are you using PhotonGI indirect cache ? It doesn't support light groups at the moment :idea:
Support LuxCoreRender project with salts and bounties

Gobo
Posts: 7
Joined: Fri Oct 25, 2019 2:12 pm

Re: Light Groups (Noob)

Post by Gobo » Tue Oct 29, 2019 8:49 am

I see. Ok, i used Photons, so that was it. Is that planned somewhen in the future, or is it technically not possible? Kind of tricky to render scenes like the ones attached with a pure path tracer at all.

Thanks for helping, Axel

User avatar
Dade
Developer
Developer
Posts: 3241
Joined: Mon Dec 04, 2017 8:36 pm
Location: Italy

Re: Light Groups (Noob)

Post by Dade » Tue Oct 29, 2019 10:10 am

Gobo wrote:
Tue Oct 29, 2019 8:49 am
I see. Ok, i used Photons, so that was it. Is that planned somewhen in the future, or is it technically not possible?
It is possible, it requires some work and it is not hard to do. But it is likely to have a separate cache for each light group so it can be quite expansive from memory usage point of view. It has also a little cost even if you use a single light group.

This is why you can do multiple renderings, one for each light group, enabling only the lights in the light group, mixing the results in post-processing and get the same result (aka light groups "by hand").
Support LuxCoreRender project with salts and bounties

Gobo
Posts: 7
Joined: Fri Oct 25, 2019 2:12 pm

Re: Light Groups (Noob)

Post by Gobo » Tue Oct 29, 2019 10:37 am

👍

Post Reply