Hi all, When I go into the group editor for an OBJ file, I am a bit confused by all of the different logical sub-divisions of an OBJ file. For example, if you import an OBJ file into your Poser scene, you have defined groups, materials etc. I am wondering if anyone has written a comprehensive tutorial on the structure of an OBJ file ? regards, Andrew

Andrew: Personally I think it would be very difficult for someone to write such a tutorial. Reason: no 2 model makers structure/name their model parts in the same way. The way I define my groups, materials, etc., would no doubt be very different to someone elses. Just my opinion ziggie

Yes, I am sure that is the case, ziggie. But I am talking about the overall general structure of an OBJ file (i.e. what applies to every OBJ file). If you go into the group editor in Poser with an OBJ file loaded, you can see that this presents a lot of options - this is what I am trying to demystify.

That sounds like something for Google to handle. Try searching for 'wavefront obj format specs' or similar.

Attached Link: http://www.renderosity.com/messages.ez?Form.ShowMessage=195387

I just found a text file that discusses OBJ files, but it is unattributed, so I will not reproduce it. Besides, OBJ files can do way more than the small part that Poser uses. There is way more in the description that does not apply than does.

We can give some of it here.

The "v" section (geometric vertices) locates the points. This one is all you need for a morph to be applied in Poser.
The X is first number in a row and -X is the figure's right side.

The "vt" section, (texture vertices) I keep forgetting what is does. But I think that if an OBJ is UV mapped, it defines the relative position of each point as a fraction of the zero:one in the X and Y dimensions of the 2D texture.

The "vn" section is the normals - Poser does not use this one itself.

The "f" faces section is the texturing and grouping.

g ____ everything below this line is that group - until or unless another g line shows up.

usmetl ____ is a material - same rules as groups.

Inside each "f" line is normals data - which is why Poser does not "vn" The progression - cw or ccw defines the direction the normal faces , but which point is the first is arbitrary as far as the net effect.

s line is smooth, I think, but P4 does not use it and I am not sure P5 notices it either.

http://www.renderosity.com/messages.ez?Form.ShowMessage=195387

Perhaps these links will help.http://www.royriggs.com/obj.html http://www.3d-cc.com/tutorials/GroupTutorial/group1.htm

http://www.tnt.uni-hannover.de/js/soft/compgraph/fileformats/docs/OBJ.format.txt http://netghost.narod.ru/gff/graphics/summary/waveobj.htm