Hi,

Is there any documentation or a sample .hip for Light Instancing in H20.5?
I guess, I could figure it out.
But how can we know to use `encodeattrib("light:color")` in the randomize attribute node?

I just discovered in the Hive video.



Is there really a difference of performance if we use point instancer vs. Reference?
I've made a setup for both in stage.



Attached my .hip

Here is some info in the Karma User Guide: https://www.sidefx.com/docs/houdini/solaris/kug/lights.html#instances [www.sidefx.com]

Houdini ships with the hip file that created those images; it can be found in $HFS/houdini/help/files/karma_user_guide.

tomtm
Is there really a difference of performance if we use point instancer vs. Reference?

The performance difference is usually down to composition overhead from instanceable references, so PointInstancers are just a single prim on the stage, so are usually lighter-weight. The renderer doesn't really know the difference between the two though, so either should work.

Hopefully this is helpful!

goldleaf
houdini/help/files/karma_user_guide

Thank you goldleaf, it's good to have some sample files. It's rocket science :-)

Just another question: What exactly means in Karma Primary Samples Minimum Samples -1? What is -1?


Thanks Tom

tomtm
Thank you goldleaf, it's good to have some sample files. It's rocket science :-)

No problem. We've also just added a related example to the Content Library. It's the Warehouse scene used for some of our launch demos. It has some complex and simple examples of light instances (as well as some other features/workflows).

https://www.sidefx.com/contentlibrary/warehouse-lights/
[www.sidefx.com]

tomtm
Just another question: What exactly means in Karma Primary Samples Minimum Samples -1? What is -1?

It means Karma will automatically pick the minimum number of Primary Samples to fire, before it starts the adaptive sampling. We'll have to make a not to clarify that info in the docs/user guide.