Light Linker Rules

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I was wondering if someone could tell me if I am missing something.

In my lops it seems the light linker rules are not being followed.(when running karma).

There is a background plane that should only be illuminated with the light named 'Bark',
ignoring all other lights.

The box over the background is suppose to ignore the Bark light.

I've turned off the box lights yet it still gets the green Bark light.(Rules say it shouldn't).

If the box lights are turned on most of the green goes away but you can still see a shadow being cast by the bark light and box.

In the file started with the prims and filled in rules with lights. I've tried it the other way around too, starting with lights and filled with prims to define rules. In either case the rules are ignored.

Attachments:
Light_Linker.hiplc (887.7 KB)

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Try setting the rules on the light itself. Adding the box to the bark light's exclusion list should do what you want.
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cubiccube
Try setting the rules on the light itself. Adding the box to the bark light's exclusion list should do what you want.

As I mentioned in my post, I've tried that. Appreciate your attempt to help though.
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Setting the exclusion rule on the bark light, in addition to whatever other rules you've already set, stops it from shining light on the box object on my machine. If you're getting a different result, perhaps it's a bug. To stop casting shadows, you have to create a separate shadow rule.

Attachments:
Light_Linker_fix1.hiplc (1000.8 KB)

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Note that KarmaXPU only got support for light linking very recently:

From the Changelog [www.sidefx.com]:
Houdini 19.0.423 | XPU: lightlinking implemented | Sat. October 30, 2021

You may have to download a new daily build to get it working with XPU.
Edited by jason_iversen - Nov. 2, 2021 17:49:55
Jason Iversen, Technology Supervisor & FX Pipeline/R+D Lead @ Weta FX
also, http://www.odforce.net [www.odforce.net]
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cubiccube
Setting the exclusion rule on the bark light, in addition to whatever other rules you've already set, stops it from shining light on the box object on my machine. If you're getting a different result, perhaps it's a bug. To stop casting shadows, you have to create a separate shadow rule.

Thanks...for some reason I was thinking shadows where controlled on the lights themselves...didn't realize although it is explicitly there in the docs of using + alt to get a shadow rule.

But the 'problem' still remains that why when starting with a prim and defining the rules with the lights that it doesn't work with excluding light from a prim. (and not the other way around which works when one starts with lights first). Although when starting with a prim and using a light shadow rule it does work.

I've simplified the file even more than last time. The box still gets the bark light even though it's specified not to.

jason_iversen
Note that KarmaXPU only got support for light linking very recently:

From the Changelog [www.sidefx.com]:
Houdini 19.0.423 | XPU: lightlinking implemented | Sat. October 30, 2021

You may have to download a new daily build to get it working with XPU.

I don't know anything about this XPU, I noticed this problem with 18.5 and have the same results with 19 production build.

Support suggested like you to try daily which I am doing atm...will post again to note if there are any changes.

Attachments:
Light_Linker_v1.hiplc (446.6 KB)

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I think I was able to get it to work the way you expect it to. I would remove the lights you have in your scene and add new ones. That helped for me. Did those lights maybe come from 18.5 ? or an older build?

Attachments:
Light_Linker_RS.hiplc (991.0 KB)

rob stauffer
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stovetop
I think I was able to get it to work the way you expect it to. I would remove the lights you have in your scene and add new ones. That helped for me. Did those lights maybe come from 18.5 ? or an older build?

You started with a light and defined the rules with the prims. That is not the issue since it works for me that way as well.

If you look at my file and see that it starts with the prims and the rules defined by the lights. It does not work.

Trying this with 427 daily which is same result as 18.5


Edit - SideFX - "Thank you for the new file and explanation.
I submitted this problem as bug #117269."
Edited by BabaJ - Nov. 3, 2021 19:18:48
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Hello!

I am experiencing something similar (im on the latest production build). I am totally new to Solaris, but since i can work with a basic scene, i added a light linker to control which objects get illuminated by which light.

The thing that happens is, in the process of adding rules in the light linker, some of my objects get no light even though the rule says it should get one. This way the geo simply becomes dark, and if i restart the render a couple of times, sometimes it fixes it, but usually it behaves something like a bug, and i can't get it to work really.

In the video from Rohan Dalvi on youtube, where he shows Solaris, his light linking works without problems.
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Here is an example.

Why does the sphere get both the red and blue light, when i have made a rule for it to only receive the red light?

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Screenshot 2021-12-07 135126.png (1.0 MB)

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