Question about Light Instancing performance & Light Instancing light pass

[freed-kenneth]

Hello,

Currently we're planning to do a large scene in Houdini with thousands of lights.
Before we start it, I would like to know more about the VrayLight.

Question1:
Is there any performance advantage of using Instancer to spawn lights instead of actually create each single light as a single node?
I'm asking this because our artists think it's much easier to adjust a light from a node. It's easy to select or see the light in the viewport.

Question2:
If I use Instancer to spawn lights, is there any way I can make a light pass of specify points?
The lightSelect element can only take a node as the input.

Thank you.

[glacierise]

With thousands of lights having each as a separate node is unwieldy, I've had good experience with point instancing them. Then you can use the point attributes for intensity and color and paint cool shapes. Light selects - you can have several instancers/lights that use different point sets and feed different light selects. Performance is quite nice too

[freed-kenneth]

With thousands of lights having each as a separate node is unwieldy, I've had good experience with point instancing them. Then you can use the point attributes for intensity and color and paint cool shapes. Light selects - you can have several instancers/lights that use different point sets and feed different light selects. Performance is quite nice too

Thank you for your reply glacierise.
I appreciate your answer, and I totally think they are the standard.

However...
The problem of point instance light is artists cannot manipulate the light directly in the viewport. And the Vray Light Lister is very helpful but only supports light nodes.

About the light pass, splitting instancer is not practical for us and is not working for some cases. e.g. If we want a same light appear in two light passes, this mean we create two instancers for that light and it leads to duplication of that light.

Anyway, if this is the limit of Vray for Houdini right now, we have to accept it.

[glacierise]

If you want to control them in the viewport, you can go with object lights - they perform as quick as the instanced ones. And to make a light show in two light selects, you can use wildcard expressions - for example cave_key light will show up in cave* light select and in *key light select.