CGAL users discussion list

[Sebastian Bachmann <>]

Hi everyone,

I have an image from which I want to create a coarse surface mesh.
The code I use for that is based upon the example 
mesh_3D_image_with_features.cpp, however it is adopted to then extract 
the surface and write an OFF file: 
https://gist.github.com/reox/0df1f446f0ff9d46e0688b60e8e858b8

As you can see, the Mesh_criteria is set to a really coarse mesh. The 
input image (attached) I use has a voxel size of around 0.5mm and 
represents a proximal femur.
Now, for some reason, I get extremely fine triangle elements in certain 
places (see attached image).

I find that peculiar, as the facet_distance is already quite large, and 
I thought that this might be the main issue here. I remembered, that 
also the relative_error_bound in the create_labeled_image_mesh_domain 
can have an influence, but reducing this rather creates a "spiky" mesh 
than removing those small elements. (Eventually when it is set to 0.1, 
the small elements vanish, but then the vertices are all over the place 
and not on the isosurface anymore...)

Is there anything I missed here, maybe did I use wrong parameters? Or is 
there another way how I could produce such coarse meshes?

Best,
Sebastian

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