jim chang

Hi everyone,

I've recently run into an issue with Agent Layer versions in my crowd simulations. I've noticed that when using the new Agent Layer (2.0) compared to an older version of Agent Layer, I'm getting different results even though I'm using the exact same model and the same bind points.

Everything works as expected with the older version, but after switching to Agent Layer 2.0, the same setup produces different behaviors/outcomes. This has me quite puzzled. 😖

I've prepared a comparison video and the relevant hip file to demonstrate the problem more clearly.

Has anyone else encountered a similar situation, or could anyone offer some insight into why this might be happening? Any suggestions or ideas would be greatly appreciated! 🙏

I will attach the comparison video and hip file shortly.

Thanks, everyone!

Hi everyone,

I'm working on rendering whitewater in Karma XPU and I'm trying to achieve a more realistic "wet look," similar to what can be done with the default Houdini whitewater VEX shader.

In a Rebelway tutorial, the instructor demonstrated how to get a nice wet appearance using the default whitewater shader by calculating gradients. This works great, but as that shader is VEX-based, it's not supported in Karma XPU.

I've tried rendering the whitewater in XPU by converting it to a volume and applying an mtlx volume shader. While it renders, the result lacks the wetness and looks quite dry compared to the VEX shader output.

Here are two images to illustrate the difference:

Image 1 (VEX Shader): This shows the desired wet look achieved with the default VEX whitewater shader. (You would ideally link or attach this image here in your forum post)
Image 2 (Karma XPU with mtlx Volume Shader): This is my current result using Karma XPU and an mtlx volume shader. You can see it's missing that wet, clumpy appearance. (You would ideally link or attach this image here in your forum post)
Does anyone have experience or suggestions on how to adjust the mtlx volume shader settings, or perhaps a different approach within Karma XPU, to make the whitewater look more realistic and achieve that wet, almost semi-transparent, clumpy feel where the foam meets the water? Are there specific mtlx nodes or techniques I should be looking into to simulate the effect of varying water absorption or specular breakup that the gradient calculation in the VEX shader might have been providing?

Any advice or pointers would be greatly appreciated!

Thanks!

Hi everyone,

I'm encountering an issue with whitewater rendering in Karma XPU and would appreciate your expertise.

Scenario:

Simulated ocean waves with Karma XPU

Dynamic whitewater: Volume-rendered

Stationary/splash whitewater: Uniform-rendered particles

Problem:
The dynamic whitewater appears unnaturally fog-like instead of having distinct foam shapes, even though stationary/splash particles render correctly with uniform mode.

Current Setup:

Dynamic whitewater: Volume rendering with @pscale attribute

Stationary/splash: Point cloud + Karma particle uniform rendering


Side-by-side comparison video (simulation vs render)
Attached:



Key Questions:

Is this caused by insufficient particle count for volume rendering?

Could there be hidden parameter conflicts between volume/particle renders?

Any recommended Karma XPU-specific optimizations for hybrid rendering setups?

Thank you in advance for any insights!