Tightening a point cloud mesh hull

[arquitextonica (Miguel Villegas Ballesta)]

Hi All.
I´m hitting a wall with this problem and I wonder if there is a cleaner easier solution.
I got a filled point cloud I want to wrap with a mesh hull.
When I use the convex hull, as reasonable, it creates a convex hull and I loose the concave parts of the shape.
Voxeling and smoothing makes me loose a lot of precision because it goes too deep inside the points.
Any suggestions? I MUST avoid coding, just pre-fab GH and GH plugins.
Thanks in advance!

SPACE FIELDS 20200605B.gh (18.6 KB)

[Joseph_Oster]

Strategy for removing points inside PointCloud

For any pointcloud, I’d like to keep only a band of the “outermost” existing points around the cloud, like the blue marked ones: [image] I would have no other input data than the cloud itself, and a desired width of that “blue band” of points to keep, [Edit:] so I wouldn’t have any curve boundary etc to know where to cull. It must all be derived from the cloud itself. At first glance I didn’t really grasp how the definition works which you posted, but I’ll have a closer look asap. Thank you…

[arquitextonica (Miguel Villegas Ballesta)]

I internalized the point cloud for you to see the result.
I had already looked at your answer to @RIL but it does not yield the results I need.
Thanks @Joseph_Oster!
I want to get the mesh hull for ANY filled (so no volumetric but massive) point cloud. I´m afraid I must be doing something wrong…

Oster answer.gh (129.4 KB)

[DanielPiker]

Maybe this is useful: Alpha Shape 3D

[arquitextonica (Miguel Villegas Ballesta)]

Thanks @DanielPiker I haven´t managed to make it work yet but I´ll try. For now I think voxelization and cocoon are the two “nearest” solutions.
Is it such a difficult computational problem? In my “human” approach an algorithm shouldn´t be hard to devise. I read about the pivoting ball, but I couldn´t find an implementation.