Does anyone know how to specify that an HDA is a light so that you can choose to look through that light in the viewport? I'm creating a gobo light using an Octane Spectron shader applied to a grid geometry. I've configured everything I can find in the Operator Type Properties window that might relate, but for the life of me I can't figure out how to get Houdini to formally recognize it as a light.

As I'm using an Octane shader in the HDA, it works in the renders, but I'd love to be able to position it by “looking through it” as opposed to using the transform/rotate handles.

Thanks in advance!

Hi,

Maybe you can build this around this node (Light template object node):
https://www.sidefx.com/docs/houdini/nodes/obj/light.html [www.sidefx.com]

it should work if you update it with what you need.

Hey Milosz,

Thanks for the tip. I couldn't get Octane to recognize a light built on the Houdini Light Template node. It works if I build it in a Geo node, but then I don't get the ability to look through the light in the viewport as mentioned. There must be some code that Octane is referencing that is not accessible in the standard HDA creation process. Even if I just straight up create a copy of the Octane Spectron light node and save it in the same directory, Octane won't recognize it so I decided for the time being to just build a Spectron shader HDA that I can target as the shader path in a Spectron light node which works well despite being two separate nodes (light and shader). This is also probably the intention the Octane developer had in surfacing the shader path as an editable field

Best / Travis

travisrogers
Hey Milosz,

Thanks for the tip. I couldn't get Octane to recognize a light built on the Houdini Light Template node. It works if I build it in a Geo node, but then I don't get the ability to look through the light in the viewport as mentioned. There must be some code that Octane is referencing that is not accessible in the standard HDA creation process. Even if I just straight up create a copy of the Octane Spectron light node and save it in the same directory, Octane won't recognize it so I decided for the time being to just build a Spectron shader HDA that I can target as the shader path in a Spectron light node which works well despite being two separate nodes (light and shader). This is also probably the intention the Octane developer had in surfacing the shader path as an editable field

Best / Travis

Hello Travis

Did you ever manage to do you own Octane Light HDA ?

So far, as long as I keep the name of my HDA to replace that of the original octane light it works, but as soon as I try to differentiate it (by changing asset name plus type like Octane Light Custom) it doesn't render anymore.

What's more, even if I use a 'blank' geo and try to call a shader that's inside that new HDA, it won't work. I'll try to bug Juanjo on the Octane forums.

Hey Bernie,

Sorry for the delayed reply. I wasn't able to figure out a solution when creating my own or even copying an Octane light. It simply isn't fully recognized as a light in Houdini in so far as I'm able to look through it in the viewer. Ultimately I just wanted to add the ability to have a BlackBody light source for color temperature as opposed to just Texture in the Spectron light options. My solution was just to modify the existing Spectron light, which works, but the downside is that I need to redo my changes every time I update Octane. It only takes me 5 min so it could be worse.

Let me know if you figure out any tricks.

Best / Travis