Strange Meshing problem

I am facing some problems meshing a closed polysrf (rhino 6)
Extracting the render mesh is giving me an open mesh no matter the settings I use.
meshing from the mesh menu gives me a closed one instead.

I am uploading a little piece of the original big masterplan file.
render mesh export test file.3dm (297.7 KB)

I know the object is far from origin and maybe that is the cause…
I am just curious to know what’s happening. @nathanletwory @andy

FWIW the render mesh is closed in Rhino 7. Not sure why it fails in v6, clearly some meshing issue.

Hi @Pitti
I think I remember running into this problem a loooong time ago and being told, that the “render mesh mesher” is optmized for speed over quality and the “mesh command mesher” is more optimized for quality. Since the mesher has been re-written for V7, it might have changed (and I unfortunately don’t recall who gave me the info, so it might be something I just made up).
HTH, Jakob

Hm - the object is only ~500 units from the world origin, so I do not think that is it, here… Using MatchMeshEdge closes up the extracted mesh.


Thanks. @pascal, I noticed it.

The fact is that I am working on a script to automatize the export process of big rhino files to 3dsmax.
For example I have like a thousand of those arcs in the original file…
At the moment I am exporting the render mesh, but if it’s safer i will use the mesh command…
I am also testing different mesh density options, I would like to give the user at least 3 levels of detail to chose from.
If there is something I don’t understand is why rhino meshing is so messed up :grin:
I don’t like to make comparisons but the same object exported with moi is incredibly clean…
I will post some images tomorrow …

Obviously moi is the mesh on the right , rhino the mesh on the left.

  • ngons applied on both.

Is it so hard to achieve a clean mesh quality?
I know in terms of precision maybe rhino is better and
the shading result is the same, but I think a cleaner meshing output it’s really important.
And polygons are 2022 for rhino vs 774 for moi after forced triangulation.