Hi,

Since the Houdini 18.5 we can normally do lpe tag in lop but I didn't find information about that. Do you knows how can we do that?

I have a other question : I try to add a crypto pass to my render but for this I think I need to create a primvar but I didn't find how can I do that ?

Thanks in advance,

Hi Jeremy

LightPath expressions can be found here.. https://www.sidefx.com/docs/houdini/render/lpe.html [www.sidefx.com]

For Cryptomatte (Karma) I have s screen grab for you as my version of Houdini is education so my HIP file will not load for you. This pic should be enough to get you going. Best Mark

Hi Mark Wallman,

Thank for your help
I finally got my cryptomatte path with your parameters + and attribute on my geo named “myname” imported by the sopcreate.

For the LPE I write my expression but I didn't find the way to add the tag “leftwall” to my geo. With renderman it's easy because you can set it in the parameter but how can we set this lpe tag in lop for karma ?

If I write * instead of “leftwall”. It's working so i think my expression is good

Edit : It's the Render Geometry Settings node for create a lpe tag on a geometry