http://moi3d.com/download/Obj23dmWireframe.zip
A converter who translate OBJ file format to format 3DM but...

Structure keeping but surfaces are not created!
So you can create yourself surface with Planar, loft etc..


With the convector inside Moi : a sort of Helpers lines in 3D ;)

You can use it for make some plan facettes ;)

Thanks, Frenchy, I know about that little app. Not the way I'd prefer to go.

Jonah, it should work when I convert the SU file to 3dm, right? I mean, that's the format that MoI uses ...

I believe that is quasi impossible to translate a polygon mesh to a nurbs mesh ;)
(only structures, not the surfaces for complex objects!
Like make an apple from the apple juice ;)

> <...> it should work when I convert the SU file to 3dm, right? I mean,
> that's the format that MoI uses ...

Hi Stinkie, MoI does use the .3dm format, but there are a lot of different kinds of things that can be stored in a .3dm file, like NURBS solids, polygon meshes, spotlights, dimensions, annotation text, etc...

MoI does not read every single kind of object out of a .3dm file, it only reads in NURBS surface objects, and single point objects.


What is probably happening, is that Deep Exploration is storing the SketchUp model into the .3dm file as a polygon mesh object - that is an object made up of triangle and quad facets.

Currently MoI does not work directly with that type of data, instead MoI uses NURBS surface data, which is a much different kind of 3D data than polygon mesh data.

It can be kind of difficult to go back and forth between MoI and SketchUp since the kind of data that they use is pretty different (polygons in SketchUp and NURBS in MoI).

You might try using Rhino for that, they may have an option over there to read in the SketchUp file and turn it into trimmed NURBS data instead of into polygon data, I'm not quite sure about that though.

- Michael

Hi Stinkie, hi Pilou,

Pilou wrote:
> I believe that is quasi impossible to translate a polygon mesh to a
> nurbs mesh ;)
> (only structures, not the surfaces for complex objects!
> Like make an apple from the apple juice ;)

Yeah, the thing that especially doesn't work well is that curved surfaces in a polygon mesh file are made up of a large number of little tiny triangle or quad facets.

NURBS are not designed to work with little tiny individual pieces, they are more designed to have a curved surface as one single spline sheet.

It's possible to process a smooth NURBS sheet into a bunch of little polygon facets by dicing it up into pieces, but it is quite difficult to go the other way and take a bunch of little tiny polygon facets and try to reconstruct a single big smooth spline sheet from it.

Usually I compare this to how you can take apples and mash them into applesauce without a problem, but starting with applesauce it is really hard to get back to whole apples again.


Now, there is an exception to this - if your object in Sketchup does not have curved pieces in it and is made up of all large planar pieces, that that type of thing could be converted more properly over into NURBS where each large planar piece becomes a trimmed NURBS plane. I think there may be an option for this in the Rhino Sketchup Importer, so if your object is made like that, that could possibly work.

- Michael

Ah! Now I see. Thanks for explaining y'all.

Rhino can import Sketchup files. And then you can run the command "MeshToNurb" which will convert every polygon face into a Nurbs plane. The new faces will be joined to adjacent planes in the same manner as the mesh was joined. then you can Copy/Paste that Nurbs object into MoI...

jonah

Hi Jonah, the problem with that method is that will result in SketchUp's n-gons being diced into triangles.

I think I remember there was another option specifically for SketchUp....

Here it is: http://en.wiki.mcneel.com/default.aspx/McNeel/ThreedWareHouse.html - that updated SketchUp importer for Rhino seems to have an additional "SketchUpImportOptions" command you can run to turn on the "TrimmedPlane" option, which sounds like it will bring in SketchUp n-gons as trimmed NURBS planes.

So that is probably the best way right now to convert SketchUp files into a .3dm file.

It still probably won't be great if you have "smooth" parts in SketchUp, but it would probably work for bringing stuff made of planes over.

- Michael

Ah, i forgot about that prototype importer. That should be the way to go. But if using the MeshToNurb version, one can always merge all the planar faces by running the command "MergeAllFaces". So i think the end result is the same...

But also it mentions that textures are lost if you import with "TrimmedPlane" option. But dicing up a mesh won't erase the textures. Anyway i guess that's not a problem for Stinkie in this case...

jonah

Thanks for your thoughts, people!

Seems I need Rhino. As I've just bought Maxwell, that's not an option. lol. What - I got a money tree? ;) I'm gonna keep your suggestions in mind, though.

I use 3d_coat for shapes difficult to do in rhino40.
Then import the obj file in rhino.
Apply some meshplanes through the obj obect.
Then Mesh intesect to find the curves i need.
Then loft to reconstruct the shape in nurbs.