Ability to Use LightSelects WITH LightMix Enabled

[Joelaff]

Hi,

We would really like the ability to use LightSelects with LightMix enabled, at the very least at render time, but ideally in the UI as well. Why? LightMix is a great way to get a channel for every light in the scene very easily. If you later want to add a LightSelect you have to manually recreate a LightSelect for every light. No fun with more than a couple lights.

Also, if you forget to disable LightMix then all your LightSelects get disabled as well. This a massive problem in production, as mistakes inevitably happen without some sort of scripting solution.

Thanks.

[matanov]

Hi,

What's the idea behind this? Using LM ensures you have all lights sources in you scene automatically packed as LightSelects depending on your grouping choice. Adding manually LSs on top of those will duplicate light contribution, which in the end will result in something quite far from the original RGB, so yeah - what's the idea?

[Joelaff]

Primarily that we would like to add LPE passes. Right now we are blocked from doing this without recreating all the LightSelects.

Also other LightSelect only features like the ability to add a pass of just the direct specular for one light. I don’t think that matches the existing LightMix channel for the light multiplied by the VraySpecular pass. (Does it? Even if pixels exceed Max Ray Intensity?)

[matanov]

Primarily that we would like to add LPE passes. Right now we are blocked from doing this without recreating all the LightSelects.

Also other LightSelect only features like the ability to add a pass of just the direct specular for one light. I don’t think that matches the existing LightMix channel for the light multiplied by the VraySpecular pass. (Does it? Even if pixels exceed Max Ray Intensity?)

I don't think multiplying will get you the right thing. More like subtracting all other lights' contribution from the Specular RE..



Anyway - I'll make a note to allow LSs with LM even if the mode is not "manual light selects".

[Joelaff]

Great, thanks! And good suggestion on extracting the specular data for the single light. Thank you.

[M.Max]

I would like to have this option too for the exact same reason.
I wouldn't mind if the light mix ignored these manually created light select element

[Joelaff]

What do you mean by ignored them?

I would like to be able to use LightMix to autogenerate light selects for all lights and work with IPR, but then ALSO be able to use LightSelect however I want-- in any mode I want, and have those actually show up in the render, even if they are duplicates. The Light Selects should take precedence if the channels names would conflict (because that way you could override a single channel, but they could also just be auto-named in such a way that they cannot conflict (prepending "LS" for instance)).

Silently disabling manual LightSelects just because there is a LightMix is not really the way to go. It's confusing if nothing else. We so often just need to add one more pass right near the end of a project just to make some comping changes, and now this makes things far more complex than they need to be.

[M.Max]

What do you mean by ignored them?.

I meant that if the lightmix already created all the needed lightselects to re-build the scene lighting , then any additional light select that I create manually could be ignored and not to be shown under the lightmix tab in the VFB, that was a suggestion for Peter to avoid duplicate light contribution issue that's mentioned earlier .

Silently disabling manual LightSelects just because there is a LightMix is not really the way to go. It's confusing if nothing else. We so often just need to add one more pass right near the end of a project just to make some comping changes, and now this makes things far more complex than they need to be..

Totally Agree .

[Joelaff]

Ah, I see. I didn't understand what Peter meant be duplicate light contribution. I was thinking that I just wouldn't use those LightSelects unless I needed them for a specific purpose in post, which is of course why I would add them in the first place. Not to use in the VFB. But it would be nice for proofing if they did show up in the VFB, but, as you say, not in the LightMix. Just treat them like another element like VRayReflection, etc.

[Joelaff]

Any chance of this making into to the nightlies sometime soon?

Thanks.

[Joelaff]

Any update on this? We sure could use it in our current and last two projects. Might this be incorporated into the nightlies?

Thanks.

[matanov]

Any update on this? We sure could use it in our current and last two projects. Might this be incorporated into the nightlies?

Thanks.

No updates yet

[Joelaff]

Nudge, nudge. This sure would be nice to have. Just find in the LightSelect code where it checks if LightMix is enabled change it to if(1)

LightSelect is also a nice way to be able to easily get a DirectDiffuse and an Indirect Diffuse (or specular) for all lights (or individual lights). If this could just NOT be blocked from running when LightMix is enabled it would solve all sort of problems.

Would be nice to have the option to potentially disable LightMix when production rendering as well. (Note I am asking for it to remain active in conjunction with LIghtSelect above, but think it would be nice to also be able to have and option for LightMix to be on only for the IPR.)

Thanks.