Hi, I was just wondering if there was a way to take a polygon object from Modo to Moi and then back to Modo while maintaining the same scale and positon information. I'm using the 'import obj' script I found on these forums to import a polygon object into Moi from Modo. However, I found that this script seems to alter transform information in strange ways. I did a small test where I created a 1 meter cube in Modo and then used the 'import obj' script to get it into Moi. I checked the unit length of the cube in Moi and it read 22 Meters. I then created five 1 meter cubes in Modo and then used the 'import obj' script again to get them into Moi. Strangely, the size of all the cubes were now 7 meters, instead of the 22 meters when I just imported one cube. I then tried importing twenty 1 meter cubes and found they converted to a 6 meter size. In short, I believe the 'import obj' script is messing with the transform info. I don't know if this is the cause for sure, but it seems to be so. I wanted to know if anyone knew how to go back and forth between the programs while maintaining the same transform information. Thank you so much. I also attached a Moi screenshot of the cubes.

Hi ratman, yes I think that import obj script does rescale objects by default, if I remember right you can set it up to not do that though. Here it is:
http://moi3d.com/forum/index.php?webtag=MOI&msg=6674.201

So for your shortcut key that you use to launch the import obj script, give it an additional paramter "exact" like this:

_ImportObj exact

That should then disable the automatic scaling.


But one thing to note is that MoI is not designed to work on polygon model data, the import obj script will make a separate individual NURBS plane for every polygon in the .obj file which is ok for a few boxes like you show there but it won't work well for something that has higher density. The way each surface in a CAD program is set up there is more information needed for each face because of how it works with an "underlying surface" that has trim curves on it marking different areas as holes. So a NURBS model made up of hundreds of thousands of little tiny flat facets just doesn't work very well, a NURBS model should be made up of a smaller number of surfaces each of which is a larger curved surface patch.

So because of that typically the workflow is more one directional like model in MoI and import into Modo. Usually the best way for this direction is to export from MoI to .lwo format, and to preserve unit size make sure the option is set in MoI under Options > Import/Export > LWO options > "Scale output units to meters".

- Michael

Thanks a lot Michael for all of the information. Now everything is importing and exporting how I want. -- I love the way moi converts nurbs to polygons, and I use this process a lot. But I also thought it might be useful to be able to go back and forth from the two programs for a few reasons. For one, I might be blocking out a design in polygons, but want to create some pieces with nurbs modeling. I could send blockout polygon geometry from modo to moi just as a placeholder so I can continue developing parts of the design in the context of the whole. Even if I didn't use the polygons directly it could be useful for this. Also, I thought you could send a sub-d mesh over to moi and the nurbs tools will work on it with the _Subdiv script. I havn't tried anything complicated yet, but it might be useful to do some finishing work, with booleans for example, on a sub-d mesh. Maybe it won't work well, I don't know. I still want to try though. Thanks again for helping me out. --worls980