Hi there,

I'm currently playing around with using LiDAR data to generate high-quality terrains in Houdini and ran into a roadblock. I have these 'voids' or 'holes' in my point cloud that are not filled by the Particle Fluid Surface I'm using to generate the mesh.

Later, when projecting this mesh onto a Heightfield Project, these holes become an artifact as seen in the image.

I also tried a VDB From Particles route, by ended up with the same issue.

I've been trying lately with little success to isolate/mask these holes to scatter additional points in them, but I'm not sure if it's a good strategy.

Any suggestions would be highly appreciated.

Thanks!

Either you fix the holes before the projection or you project differently. I currently don't have the time to create an example but here's how I used to do it:

1. use polyfil with Patch Group active
2. use split with that group
3. delete any patch pointing downward
4. Merge and fuse

The other methode is to project with a Volume Wrangle. You use the intersect function and for any voxel that doesnt hit anything (primhit == -1), you use the xyzdist function and primuv function to get the nearest position.

-Olivier

Another way would be to follow your heightfield project with an inverted heightfield mask by geometry, and blur the masked height values.

You may get better results by using the Point Cloud Surface node. Also of interest: Point Cloud Normal and Point Cloud Reduce nodes.