Forum: Poser Technical


Subject: What subdivision scheme does Poser's "polygon smoothing" use?

odf opened this issue on Jan 18, 2009 · 9 posts


odf posted Sun, 18 January 2009 at 2:49 AM

Hi folks,

I've tried various combinations of "Reyes" and "Vortex" with "smoothing", "subdivision" etc, but couldn't find any concrete information on what's actually going on. Is it a trade secret?

Basically what I'd like to do is the following: I have a ca. 9000 poly figure that renders nicely in Poser when I subdivide it once in Wings. Subdividing in this case means SubD a.k.a. Catmull-Clark. Poser's Firefly renderer does something different, and meshes that work well in SubD don't necessarily in Poser. Now fixing this while working in a SubD modeler is obviously a bit tricky, but if I knew the actual algorithm, I could try to reverse it, starting from the higher res figure and thus create a modified version of my original figure that would be closer to the higher res one after one subdivision step in Poser. So, presumably, it would render better and look smoother.

I hope I made myself halfway clear. Anyway, any info on how the subdivision works?

Cheers,
Olaf

-- I'm not mad at you, just Westphalian.


Cage posted Wed, 21 January 2009 at 3:24 PM

My understanding has been that Poser doesn't really apply subdivison in the sense that Blender, say, does (applying it to the actual geometry), but merely applies the smoothing during the render process. 

I think the Poser smoothing was being called "micropolygon smoothing" around the time Poser 5 introduced it.  Googling that phrase seems to bring up references to the Reyes which you mention. 

Not too informative.  Sorry.  😊  I'm sort of hoping someone more knowledgeable will come along to address the question.  I'd like to know, too!

===========================sigline======================================================

Cage can be an opinionated jerk who posts without thinking.  He apologizes for this.  He's honestly not trying to be a turkeyhead.

Cage had some freebies, compatible with Poser 11 and below.  His Python scripts were saved at archive.org, along with the rest of the Morphography site, where they were hosted.


Cage posted Wed, 21 January 2009 at 4:38 PM

Oh, I missed my editing wondow for the above post.  The Reyes page to which I provided a link states that Pixels 3D uses Reyes.  Wasn't Firefly based on Pixels 3D?  Or was that the material room nodes?  Hmm.

===========================sigline======================================================

Cage can be an opinionated jerk who posts without thinking.  He apologizes for this.  He's honestly not trying to be a turkeyhead.

Cage had some freebies, compatible with Poser 11 and below.  His Python scripts were saved at archive.org, along with the rest of the Morphography site, where they were hosted.


odf posted Wed, 21 January 2009 at 5:15 PM

Well, one could apply SubD for smoothing during the render process. In fact, I believe some render engines do just that, due to some nice limit properties of SubD surfaces. But you're right, that doesn't necessarily mean that any smoothing applied during rendering can be interpreted as a subdivision process on the mesh level. In fact, I'm starting to suspect that the micropolygon smoothing in Reyes might work entirely different.

Anyway, still interested in getting some more info on the process, if someone comes along who has it.

-- I'm not mad at you, just Westphalian.


msg24_7 posted Thu, 22 January 2009 at 12:08 PM

Maybe this site sheds some light on what's going on within Poser's Firefly renderer...
www.steckles.com/reyes1.html

Yesterday's the past, tomorrow's the future, but today is a gift. That's why it's called the present.


Miss Nancy posted Thu, 22 January 2009 at 5:11 PM

there are numerous references in these forums that FFRender is a reyes renderer.
I useta know how to examine the FFRender code in OS X with a package viewer,
but I forgot how.  maybe if ya read thru the FFRender code, it will say what subdivision
smoothing level (e.g. 4, 6, 8 et al.) it uses for render smoothing.  maybe it only smooths
the quads and skips the triangles.



odf posted Fri, 23 January 2009 at 4:32 AM

Quote - Maybe this site sheds some light on what's going on within Poser's Firefly renderer...
www.steckles.com/reyes1.html

Yep! Thanks for that. That actually clarifies what they mean by dicing (although I began to suspect it was something along those lines).

I'm still quite unclear how they do the smoothing, though, and haven't found any useful information in any of the descriptions of the Reyes algorithm I've seen.

-- I'm not mad at you, just Westphalian.


stewer posted Sat, 28 February 2009 at 8:11 PM

Attached Link: http://www.cise.ufl.edu/submit/files/file_020f70fe71888f602530143e2e326be2.pdf

Poser's "smooth polygons" converts polygons to bezier patches at render time. Do a search for "pn triangles", that should give you pointers in the right direction. I noticed that in Hexagon 2.5 you can select "bezier interpolation" as smoothing operator, which comes reasonably close. That could be of help when modeling content for Poser.

odf posted Sat, 28 February 2009 at 8:24 PM

Thanks! That's exactly the kind of information I was looking for.

-- I'm not mad at you, just Westphalian.