I have a question about the intricacies of C's .obj import/export.

I'm modeling a vehicle body in the vertex modeler. You can see the shape is very planar & angular. The model shot shows the blue edges as creased (sharp) and the gray links as smooth. The render looks good. I export as a .obj to make a UV texture map, then import the .obj. I suspect the .obj format ignores a creased edge and turns everything smooth (all the gray links in the model shot). You'll notice the render makes it look like gummi-truck. Of course, I can't explode it in the vertex modeler to crease the sharp edges - this negates the UV mapping! Is there a trick? A setting? Is the .obj / UV map only good for smoothed organic shapes?

I have to add, I've enjoyed using the vertex modeler after doing Litst's vertex Head tutorial. First-rate! Thanks!

When you export from Mac UVMapper, it will produce those smoothed edges if you don't check "Split Vertices", but all the Mac versions of UVMapper I've tried have crashed when I've used that command. I think Steve Cox is aware of the problem, and may be fixing it in the upcoming Mac version of UVMapper Pro. Carrara seems to split vertices by default, so it may help to re-export the UVMapper object from Carrara, then re-import it, but I haven't tried it. Another option is to try to create the mapping mode in Carrara (probably parametric for each group of polygons, using the texture "room"), then use UVMapper to produce only the 2D template, which would be one of those "multi-layer" jumbles until you separate out the various groups. By the way, I heard that Metacreations Carrara 1.0 was unstable with the Save command, but yours is the first time I heard it was a conflict with Navigation services. I've been using Carrara Studio with OS 9.x, so I missed out on that, but I do recall problems with OS 8.1 and GraphicConverter 3.x, where I had to turn off Navigation services or some similar action due to crashes.

Glad you liked my head tutorial, Thirteener :) One thing you can try is to export the model to 3DS, then re-import it in Carrara . You'll keep the UVmapping and the import options will let you define a smoothing angle (it works for 3DS but not always with OBJ) . I hope it will work, i haven't checked . litst

Problem solved. In short, it's all Carrara's fault. Or it might be the .obj format. I experimented along the lines as nvar1ath0tep suggested, splitting apart the different sides: back, top, left, etc., grouped them together and exported the group as obj. I opened it up in UVmapper and selected the Box projection to show the six sides, then selected each object and projected each one as Planar and arranged them on the sheet. Opening it back up in Carrara, no problem, it took the Parametric texture map. The edges of each object - top or left or back etc. - were creased, but the edges inside each object were smooth and gummi. So I started experimenting with cubes. The results are shown above. Either in the export to obj, or in the import to Carrara, all edges are made smooth, whether they were creased or smooth to begin with, and no matter what the angle of their facets. All edges, that is, except the edges of a polymesh. The outer edges were left sharp. I tried one cube of one polymesh, and one cube broken into two polymeshes. You can the the two meshes pulled apart in the model room image. The two halves are put close together, but their vertices are not welded. So sharp-edged obj imports can be made of seperate objects, or one object with seperate polymeshes. Live and learn. 13r

Nah, it's definately Carrara's fault - try importing a mesh from RDS - you get the same problem - all the angles are smoothed over - try importing the object and reducing the smoothing angle - The only imports that seem to hold their creases are 3ds files. I hate Carara's import ability - I've had too many problems with crossing over from RDS to Carrara and having to re crease all the damn edges! I end up just exporting from RDS as a 3ds file (which doesn't work all the time) and importing that way. It's a bug that hasn't been fixed or even bothered with - and it's anoying as hell :)