How to fix surface isocurves

I was sent a sketchup model. I ran MeshToNURBS, deleted the mesh, and now I have good geometry but the isocurves are all weird. How do I fix this?

Why you need them “fixed”?
If it is for visualization purpose I can suggest you to switch them off by the object properties.

Otherwise I can’t understand what’s improving. From my experience they’re not affecting the 3d modeling.

I still think it’s a fair question to ask why they ended up this way from the conversion process. They are, after all, isocurves and I expect them to align with the principal edges as they usually do when surfaces are originally created in Rhino. What’s different here? Or are my expectations naive?

This is a very helpful, and attitude-free, response. Thank you. Interested to see if the McNeel team have an answer.

Hi Thomas - the isocurve direction looks like it is aligned to the diagonals - I am not sure why ot does this - no doubt the two triangles making up the quad were like that - but in general it should not matter - if you need to align them some particular way you can try this-

PlanarFaceDirection.rhp (17 KB)

Unblock the plug-in in Windows Explorer and then drag and drop onto Rhino - the command is also PlanarFaceDirection and it gives you a few automatic alignment options as well as by hand.


Absolutely right to ask.
It’s a known behaviour in Rhino and should be fixed in the Wip8. pascal answered you with that script that should be integrated in wip8, @pascal am I wrong?

I remember the same discussion in another thread.