Obeida Zakzak

Hello,

Noticed same thing on these nodes in Houdini 20.

Looking inside, these nodes use a visualize sop with "Attribute As Is" mode. So it looks like the behaviour of this mode has changed from black/red to black/white in Houdini 20, this applys to any attribute, on any class.

Current method for me is to set a Scene Visualizer with desired color ramp on @curvemask attribute, as it's used by Guide Mask and Guide Process nodes for visualization. This way you get same behaviour on all nodes without adding a visualize sop.

Here's a possible method without having to loop over samples, which executes fast on 13M points.

Couldn't find your model to test over it, as it wasn't attached on your post.

1. Create f@h attribute and zero-out altitude on points
2. Use a Fuse SOP to snap points and average their f@h value : this will result with an average along Y-axis
3. Transfer f@h from fused/averaged points to the zero-altitude points
4. Copy back f@h to original points

In Houdini 20, SideFX introduced a new syntaxe for OpenCL, similar to VEX with @-syntaxe, and they provided a documentation for this one https://www.sidefx.com/docs/houdini/vex/ocl.html [www.sidefx.com]

So it might help in case you are familiar with VEX.