Working with light groups

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lighting_freak
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Working with light groups

Post by lighting_freak » Mon Apr 09, 2018 9:20 pm

Hello,

just realized that lux core renders all light groups that are available within a setup even when they were swithed off before starting the render.
Basically I like the idea that light groups could be switched on and off while rendering them, but on the other hand I'd like to permanently exclude some light groups from single renders.

Is there any suggested workflow to stop some light groups from being renderd. Ideally without touching the source or material definitions.
Thank you.

BR
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B.Y.O.B.
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Re: Working with light groups

Post by B.Y.O.B. » Mon Apr 09, 2018 9:35 pm

I also find this annoying and it is on my todo list but I didn't find the time to address it so far.
So no, currently there is no way (however maybe you can do it with Blender trickery, light groups are a scene property so if you create a second scene and link in all your objects, you should be able to define different/no lightgroups, but I did not test that so far).
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Dade
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Re: Working with light groups

Post by Dade » Mon Apr 09, 2018 9:38 pm

lighting_freak wrote:
Mon Apr 09, 2018 9:20 pm
just realized that lux core renders all light groups that are available within a setup even when they were swithed off before starting the render.
Basically I like the idea that light groups could be switched on and off while rendering them, but on the other hand I'd like to permanently exclude some light groups from single renders.

Is there any suggested workflow to stop some light groups from being renderd. Ideally without touching the source or material definitions.
It may be somewhat related is this iusse: https://github.com/LuxCoreRender/BlendL ... issues/101

But probably the simpler solution is to just keep light groups on different Blender layers and turn them on/off :idea: :?:
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B.Y.O.B.
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Re: Working with light groups

Post by B.Y.O.B. » Mon Apr 09, 2018 9:44 pm

Dade wrote:
Mon Apr 09, 2018 9:38 pm
But probably the simpler solution is to just keep light groups on different Blender layers and turn them on/off
They are a scene property.
Currently, if you define 4 custom light groups and assign no lights to them, you get the default light group plus 4 black images.
Obviously we need some kind of cache during export that checks if a lightgroup is not used by any light and skips the definition of the LuxCore outputs for this lightgroup in that case.
And a manual switch to disable a light group would be good as well (e.g. if you run into RAM issues).
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lighting_freak
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Re: Working with light groups

Post by lighting_freak » Tue Apr 10, 2018 7:14 am

Hi,

I think two buttons for light groups could solve the issue.
One is like hide/show, the other is ón/off.

Sounds somewhat too simple, probably I forgot to think about some setup situations.

BR
OS - Windows 7 X64
CPU - Intel CORE i7
GPU1 - Variants of notebook card from nVidia
GPU2 - Variants of notebook onboard card from Intel
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Dade
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Re: Working with light groups

Post by Dade » Tue Apr 10, 2018 9:44 am

B.Y.O.B. wrote:
Mon Apr 09, 2018 9:44 pm
Dade wrote:
Mon Apr 09, 2018 9:38 pm
But probably the simpler solution is to just keep light groups on different Blender layers and turn them on/off
They are a scene property.
Currently, if you define 4 custom light groups and assign no lights to them, you get the default light group plus 4 black images.
Obviously we need some kind of cache during export that checks if a lightgroup is not used by any light and skips the definition of the LuxCore outputs for this lightgroup in that case.
And a manual switch to disable a light group would be good as well (e.g. if you run into RAM issues).
I think the problem is not the memory usage but the rendering time: light sources of a light group with a 0.0 scale are still sampled (for obvious reasons). This means the rendering is a lot slower if you don't plan to change the light group scale.
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B.Y.O.B.
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Re: Working with light groups

Post by B.Y.O.B. » Tue Apr 10, 2018 9:51 am

Ok but we're talking about two different issues then.
I'm talking about lightgroups that have no light assigned to them.
You're talking about lightgroups that have lights, but are disabled at render start and still get sampled.
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lighting_freak
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Re: Working with light groups

Post by lighting_freak » Mon Apr 16, 2018 5:35 pm

Hi,
You're talking about lightgroups that have lights, but are disabled at render start and still get sampled.
yes, you're right. Do you think there might be an option in luxblend to disable lightgroups for rendering in near future?

BR
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dobe
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Re: Working with light groups

Post by dobe » Fri Jul 13, 2018 8:09 am

how can i use the LuxCoreRender Light Groups general in Blender?

set the light groups is not the problem, but can't find the controllsetting while rendering? i searched in the image editor!? :?
Win7 - i7 4770k - GTX 770 - GTX 1070 - 32RAM

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B.Y.O.B.
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Re: Working with light groups

Post by B.Y.O.B. » Fri Jul 13, 2018 8:51 am

Use the controls in the properties, scene tab.
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