Seperate land, tree and building in e57 file

Hello,

I am trying to separate land, tree and building in an e57 file(originally LAZ file, transformed through CloudCompare).
And I have two questions regarding it.

1 I opened the e57 file directly in Rhino.
I exploded the model to separate the points.
But the points look much larger after the explosion.
I am not sure if it is the right way to do this?
Before the explosion


After the explosion

2 After the points picking and separation, I want to turn the land points into a mesh.
I used the patch function by following the tutorial.
Because there are a lot of points, I set the patch as following image


But the result is out of control,

Could anyone help with this?

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Try meshpatch.
But remove duplicate points first.
(SelDup and delete)

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Why you do not estimate pointcloud normals and mesh it using Poisson surface reconstruction in CloudCompare? Poisson will create closed mesh, so output Distance Field to crop correctly.



2 Likes

Thank you!
Meshpatch works better than patch in this case!
And great to have the tip about SelDup : )

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Using Pointcloud normals and Poisson surface reconstruction in CloudCompare is much easier and have a better effect than doing it in Rhino!
Thank you for this!!

I still meet the problem of splitting mesh in Rhino. I cannot separate the tree part from the land and building part. Could you help with this?

3dm file attached, in case it is needed.

Mesh_3.3dm (11.8 MB)

Also in Cloudcompare use SOR filter, to discretize cloud into components, it would split the cloud into this landscape part and separate small elements.

For rhino, there is Volvox and other plugins, it is mainly , loading, cropping, section, distance functions. However, Volvox has command-line interface where you can call cloudcompare.

2 Likes

Thank you so much Petras!!

Sorry for the late reply.
My Laz meets a opening problem. I will figure out and try the SOR filter you mentioned!

Thank you for the recommendation and elaborations of the plugins!