Accurate exporting as OBJ. from Rhino to Blender

Hi guys, so I have the following problem:

I’m trying to export a file as an OBJ. from Rhino to use it in Blender, but when I export the file as an OBJ. (I already tried different export settings) and then import said OBJ. file to Blender, the Vertices are all over the place.

So my question is: Is there a way to export an object from Rhino as an OBJ. which doesn’t place Vertices all over the Object but ONLY in logical and needed Positions (e.g. Corners).

Thanks in advance for your help!

To what Blender version are you using?

Vertices all over the place makes me think you’re are trying to export something really, really big (unit-wise).

Have you tried the import_3dm add-on for Blender already? Just ensure you save your 3dm file with render meshes in it, then use the add-on to import your 3dm file directly into Blender.

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I didn’t try the add-on yet, but i have it installed now. How do I make sure that there are render meshes in my saved 3dm file?

btw thanks for the quick answer

You put the viewport in render view and click zoom to fit the whole objects in the file, then save the file with rendered viewport option enabled. At least that is how i do

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You don’t need to keep the Rendered viewport in use. But you should at least toggle once to it before saving your 3dm. The Rendered mode causes Rhino to generate the render meshes for geometry objects.

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Alright guys, at first thanks again for your help.

I attached an example Rhino file as well as screenshots from my export settings and the result in Blender using the recommended add-on. I also attached a similar “example cube” modeled directly in blender to illustrate how the ideal result from exporting from rhino and importing that file to blender would look like.

My export settings in Rhino and my screen before exporting:

This is how the mesh of the cube looks when I import the 3dm file to Blender:

When I create a similar cube in Blender the mesh looks like this:

Here is the Rhino File of the cube:
Cube.3dm (252.3 KB)

To sum everything up and rephrase my problem / question:
Is it possible to export a model made in Rhino in a way, that when I import it to Blender, the Mesh looks as clean and simple as the one in my reference pictures (from the Cube modeled in Blender)?

Or do I have to model the cube in Rhino in a certain way to achieve a clean mesh in Blender?

What you see after importing is the mesh as a result from the Rhino mesher code used for meshing all geometry (expect meshes).

As a comparison with the cube selected in Rhino run the command _ExtractRenderMesh. Hide the original cube so you can see the mesh that Rhino generated.

Not sure if there is any effort in getting clean(er) quad-meshes out of the mesher, but you can select an object and in its object properties panel set a custom render mesh. Not much you can do there though.

For more complex objects the results are generally quite acceptable, though.

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I know absolute zero of Blender, but couldn’t you use any of blender commands like MeshRebuild or something like that to simplify stuff already inside Blender?

Also, if you generate the mesh inside rhino then import, will the mesh be imported as it is or will it be remeshed during import?

I am downloading blender to try some stuff with it right now.

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Data gets imported as is where possible. At most approximations are made where a geometry type is different or none-existant. Mesh data does not get remeshed during import.

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Hi Nathan,

I have some subD models. Can I import the rendermeshes of the subD to blender, with your plugin? I tried it, but it doesnt work.

In the master branch there is already code that supports SubD. I have been waiting for the rhino3dm modules to get updated. I believe that happened yesterday. I’ll put out a new import_3dm version this week based on that updated rhino3dm version.

90 / 5.000

Übersetzungsergebnisse

Hi Nathan,
have you already managed to adapt the plugin for SubD?
Best regards
Nik

I have not yet tested with the latest rhino3dm, I hope to get to it soon.

Hi Nathan,

When trying to install the import_3dm in Blender for both v2.93 and v3.2 i get the following error.

Any idea?
Thanks in advance

UPDATE:
SORRY for the inconvenience just the installation Note in GitHub.
Please disregard my message :slight_smile:

look like you forgot to install the python rhino3dm module

open the python thingy or the cmd and run pip install --user rhino3dm

I think it is kinda the python interpreter for rhino files or something like that

That is not needed, the installation note says it all: there will be an error, restarting Blender solves it. The MacOS and Windows versions of the add-on come bundled with rhino3dm, installing other versions is not a good idea.

tried to install it after a restart but always got the same error list
dunno really how to solve
any ideas?

I’ll have to test against the officially released Blender 3.2.0, but this should work:

  1. install https://github.com/jesterKing/import_3dm/releases/download/0.0.10/import_3dm-v0.0.10-py3_10-windows.zip in Blender 3.2
  2. try enabling addon
  3. restart blender
  4. enable addon

There should be no need to reinstall the addon each time you restart Blender

addendum: make sure you unblock the ZIP file before attempting to install. In file explorer right-click on the ZIP file, select properties… and towards the bottom of the properties screen unblock if there is the checkbox for it. Apply.

I just went through the motions, it installed just fine.

oh, that is weird then, because when I had this problem I restarted both Blender and the Computer and it did not work, but it worked fine after I installed the rhino3dm package via cmd.

Worked fine
Thks
Gerry