Ken wrote:
> I believe this is supposed to unify the normals of the triangles
> as it reads in the mesh. If you haven't tried it do so now.
> 
> If you have it checked try unchecking it and see if it makes a difference.


Arg! So close! I checked unify and indeed, it did make a
remarkable difference both to the preview and the export, but
although it made the top 4/5ths of the test object solid, the
underside was still inverted (although, to its credit, it was
now inverted consistantly for all polygons across the bottom,
which, I suppose qualifies as an improvement in a weird, 
Dilbertian kind of way <g>)
 
> You might also give Crossroads a whirl. Is has a normalize triangles
> option that might or might not help.

Tried it. I've got both 3DWin and Crossroads installed, and
I'm getting pretty much equivalent results with Crossroads
conversions. The smoothing results don't help (although its
no worse than before)

Since my original post, I've tried a few tricks and outright
deceptions, like deliberately reversing the normal on every
alternate triangle (Poser didn't care or notice, and 3DWin did 
the software equivalent of saying "what the @#$@#$" and locked up
Windows) and I haven't found an option for backface culling as
Warp suggested, so my tentative opinion at this point is to go
with Ron's idea that the normals I supply are being for some
reason thrown out and new ones computed "for" me. Oddly, Rhino
couldn't care less, and both its shader and render modes show
a solid object, so I'm guessing it has something to do with what
manner of shaded preview is used by the package in question.
It just puzzles me that OBJ files I've obtained elsewhere don't
do it. I've even tried converting them to smoothed RAW and then
back to OBJ, so it isn't the process of going from RAW to OBJ,
so right now I'm doing a slow laborious line by line analysis 
looking for anything that isn't like my output. Current odds 
are 9:4 I get bored before I find something though :(

Thanks all for the suggestions. If I figure it out, I'll
follow up on this post.

Charles

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