Can anyone help me figure out the correct way to set this up? I have a little test scene attached using Cd to colour some emissive lines.

Here's where i'm stuck:

1. I need to set an emission above 0 in the shader as well as intensity on the geometry light. Should the shader emission just be left at 1? Why both seemingly conflicting settings?

2. How can i set the geometry light geo to not be visible nor cast a shadow (like from another light)? It seems like i need to combine -shadow and -primary but Render Geometry Settings doesn't allow for this


...ok since posting i've found and read through the below link regarding this. But i'm still unclear; what is the best method of using Cd/userdata to colour geometry lights?

https://www.sidefx.com/docs/houdini/solaris/support/geometry_lights.html [www.sidefx.com]

tomwcutler
1. I need to set an emission above 0 in the shader as well as intensity on the geometry light. Should the shader emission just be left at 1? Why both seemingly conflicting settings?

in the Material Glow Tints Light mode the material emission is multiplied with light settings for the actual light intensity, however the object still renders only with the Material itself
I'm not sure what you are asking exactly, but in case you would want your light geo visible I'd say tweak the Material emission intensity to the value you want the object to appear as and then use the Geometry Light settings as an additional multiplier for emitted light

tomwcutler
2. How can i set the geometry light geo to not be visible nor cast a shadow (like from another light)? It seems like i need to combine -shadow and -primary but Render Geometry Settings doesn't allow for this

this seems to work for me

the only thing I noticed is that when using this particular render visibility configuration, the light becomes sticky and doesn't update in the viewport until I force it with bypassing/unbypassing the geolight node or something, likely a Hydra2 issue

Thank you for taking the time to get back to me

1. Got it... so use the material as the visible light, Geometry Light for the actual lighting part...this is simple enough

2. works for CPU but not XPU... is this expected?