Hello,

I'm trying to set up a number of lights in which each individual light affects only certain objects.

In searching the lighting tutorials and net I could only find some reference to creating a light bank.

I did see an Odforce forum reference to a guy asking the same question but for some reason the forum seems to be inaccessible at the moment.

So in reading the docs it seems to do what I want I have to link my light to the specific objects I want to be only affected by that light.

The docs tell you how to create a light bank in a window pane, and my light is listed there.

However I can't do the next step that the docs describe, which is:

Link a light to specific objects

1. In the spreadsheet, click the “Link” cell for the light.

2. Click the icon to select the objects from a chooser, or if you know the paths of the objects you want to link, you can edit the cell contents directly.

Editing this cell automatically sets the Light mask on the linked objects. You can use a name pattern (for example hero*).

My problem is that I'm not sure what the docs mean by “Link” cell for the light.

I am assuming its my light listed in the data tree, and I've tried clicking on that and others but I can't seem to get any “objects from a chooser” which I am assuming if I could would let me link the desired object/s to my light.

Perhaps I need to go about this in a different way that what I am assuming.

Any help is much appreciated. Thanks.

* The attached image file is just a screenshot of my “Data Tree Light Bank” that I have.

Hi
Your'e missing a couple of columns in your lightbank. What version are you using?

-b

There is an actual screen type called “Light Linker”. Create one of those. Select a light on the left and whatever is highlighted in the objects on the right get lighting information from the light on the left.

It is pretty easy to use, just add one to your scene and it will make more sense.

In my scene I have three white objects and three colored lights. The RED pointlight1 is linked only to the white tube which gets colorized only by that light.

Thanks Guys for the feedback, really usefull.

I'm using 15.5 bonsak…it appears light bank won't let you use ambient light source.

As soon as I included a different light source like your area lights…the extra column showed up and I could select objects for that light source(area); Except..still wouldn't let me select objects for ambient light.

So thanks Enivob for your example because if I really want to use ambient light source, using light link lets me use ambient light source linked to objects.

On a side note, I originally came across the light link way but when I looked into the docs sidefx suggested after Houdini 13 to use light bank - don't know why, but being inexperienced that's what I tried doing first, hence this post.

http://www.sidefx.com/docs/houdini/ref/panes/linker [sidefx.com]

'ambient light' and ‘light linker’ are not really used anymore - old technology for most use cases.

I was about to comment last night Artye..that sometimes old technology is the best technology because instead of using ambient lights with Light Bank I tried using Enviroment Lights with Light Bank…but for some reason I ran into the same problem as ambient lights not being able to use the link column.

However, I gave it a try again today and I think I must have been doing something on my part last night that prevented it; Because otherwise Enviroment Lights and Light Bank work well together.

Just have to keep in mind that if making a copy of an Enviroment Light node the light bank has two references; One is the name of the light node and one is a tag reference. In copying the node it also copies the same tag so even though you have a different link for each row, if the tag is the same, your result won't be as expected (Probably what I had mixed up last night).

But for anyone that has been following this thread.

Not only did I wan't each object to have it's own light source, but that also other objects won't occlude each others light source.

Ambient light and Light Linker allowed me to do this..but so does Environment Light ( with shadows turned off ) with Light Bank allow me as well.

The “new” technology works.

Thanks again guys for the input.

Enivob
There is an actual screen type called “Light Linker”. Create one of those. Select a light on the left and whatever is highlighted in the objects on the right get lighting information from the light on the left.

It is pretty easy to use, just add one to your scene and it will make more sense.

In my scene I have three white objects and three colored lights. The RED pointlight1 is linked only to the white tube which gets colorized only by that light.

what if you wanted a group of objects inside your geometry node to be affected by a particular light?

You could create extra obj nodes and pull in specific geometry with object merge node.

On the obj node under the render tab you can put the name of the light/s in the light selection parameter.

The name of the lights are defined in their categories.

I use this method since my scenes are not large nor do I need to make many changes often for testing, variations, etc.