How to maintain Mesh Edge Hardness?

guys,. how do I control smoothing group after I export my model via OBJ?
I export Rhino Mesh (welded vertices) with “polygon” Obj setting and when I open it in MAYA all the edges are smoothed. (in 3dsmax this is called smoothing group)

how to make sure Rhino Mesh export without any smoothing group applied to all of my edges?


I’m pretty sure what you see is what you get when you export a mesh out of rhino, no matter the format. Are you previewing your mesh before export and liking what you see? Maybe share an example with us?

Hi Runnie- Unweld the mesh before exporting - Zero degrees in the Unweld settings - does that do it?


hi, if I unweld my mesh, I will have hard time welding it back in Maya (though I can use global welding with tolerance, sometimes it is very risky when the mesh is so complicated that I could miss out some vertices being welded because they are tucked in small crevices…) that is why I am pretty sure there is a way in rhino to set vertex normal direction before exporting. (although I couldnt find this option under OBJ setting, perhaps it exist in one of RHino tool?).

here I attach the breakdown process =

1.I created Mullion via Grasshopper and I set the final product to mesh with each vertices are welded, creating a solid mesh. I have searched through RHino’s command and couldnt find the tool to adjust Vertex normal, so the resulting mesh edges in RHino are all smoothed in every direction

and this is what I got when I open it in Maya =
notice that all edges are smoothed (due to vertex normal direction is automatically set to a high degree angle in Rhino)

I had to fix it in Maya… this is the result after I fix the vertex normal direction in Maya =

however it would be great if I can have full control of Mesh edge hardness in RHino so I dont have to fix it after exporting.

hope you guys understand what I mean

sorry for my bad english.

thanks :smile:

I’d think Unweld, at maybe 90 or a little less, judging from your images, and ModifyNormals=Yes would do it.


I see, thanks pascal,that would do the work :smile: