Hello,

Trying to figure out a way to use noise on a deforming volume at render time. I successfully got it work by reading a rest attribute from a point cloud at render time using Karma Point Cloud Read. The issue is that render time is drastically increased. This increase happens with cpu and xpu, but it is far worse with karma xpu. The render time of a frame goes from around 14 seconds to over a minute. I included the hip file. Please note you have to run the rop geo in the setup node at /obj for this to work. This saves the point cloud with the material in stage uses. If you look at the material, you can see the difference in render speed by cutting the wire to Karma Point Cloud Read.

I found a faster way of doing this, instead of using the karma pc read, I just convert the point cloud to a volume and use that in the material. Great work around, but would still like to know why this node is so slow.

evanrudefx
I found a faster way of doing this, instead of using the karma pc read, I just convert the point cloud to a volume and use that in the material. Great work around, but would still like to know why this node is so slow.

What is the basis of comparison for 'slow'? Is it slower than using a comparable point cloud look up in Mantra?

jsmack

evanrudefx
I found a faster way of doing this, instead of using the karma pc read, I just convert the point cloud to a volume and use that in the material. Great work around, but would still like to know why this node is so slow.

What is the basis of comparison for 'slow'? Is it slower than using a comparable point cloud look up in Mantra?

The basis of comparison was stated in my previous post. I said in my first post when you use karma pc read (instead of just using the position for the noise) the render time of that simple volume goes from 14 seconds to over a minute. In the new method I found, the render time stays at 14 seconds, hence why it is faster. As I was saying, still unsure why pc read is so slow (or maybe that is normal, this is why I am posting).