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Stahlberg
06-10-2005, 07:53 AM
Some questions recently came up, in a thread by drawdraw.com, about the topology and method I use in this face. I'm starting a new thread about it here.

"Using SOME triangles and 5-sides in the low-res base geometry can really help in keeping it lighter and more organic looking, and making it quicker and easier to model and to keep a good topology.

Here's an example, using Smooth Proxy. It works fine when deformed, too.

I never model and tweak and make UV's or Blendshapes on the high res mesh. I do all that in low-res and use a Smooth Proxy to convert to all quads, as the last step, at render time. Or when I export to Zbrush. Seems to work great."


http://www.androidblues.com/facescreen5.jpg


http://www.androidblues.com/neutralSmooth.jpg


http://www.androidblues.com/facescreenSmooth1.jpg


http://www.androidblues.com/449Lores1.jpg


KWAK wrote: it may just be the image compression, but it looks like you're getting some pinching on the bridge of the nose and the middle+upper brow, I'm wondering if that's due to how the smooth proxy is subdividing the 5-sides/tris.

It's not caused by 3- or 5-sides, it's caused by me turning certain edges into hard edges, on purpose, to get sharper creases and save on geometry. It's a calculated risk, because it might show up on certain shaders in extreme closeup, but in this case it didn't.

Phrenzy84
06-10-2005, 08:16 AM
i take it you used this hard edged method when it came to the cheek muscle/ laughter muscle (sorry my exactfacial muscle names is escaping me). I agree on some level that having 3 sided poly or n-gons can help in the topology etc. I also agree again on some level this can give organic effect, most of an non-procedural natural to the geometry.

At the moment, i am adopting a technique that i have never used on my female face, model low rez, smooth then tweak, slightly the hi res. May seem silly but it can tottaly change model and give it a feel that is something not made by poser or something. Great thing about it is that once you have finshed your model lowrez without any edges that have verticies that only share two edges everything becomes quads, which makes it eaier for uv, rigging etc.

I will probably do the rigging aspect in this stae aswell, as i havent tried it before it will be something to look forward to the results.

Your model has creases yet still looks young which i like, one thing that im sure alot of us have noticed when it come to life figure drawing, learning how to put a crease on a good looking model it difficult, as once you do it make him/her look old. Its all done with shading. So i like your apporach to it, especially the forehead, though because of the miss shader seem to wipe a away some of the detail.


love to see some more blendshape test. Low the high rez, seeing how the geometry deforms with it.

ynvamsi
06-10-2005, 09:24 AM
3 sided poly or n-gons are acceptable on face, upto now i didn't find any difficulty while doing blend shapes or uv's unwrapping for faces with 3 sided poly or n-gons.

hey Stahlberg u have started a good thread.

Stahlberg
06-11-2005, 02:51 AM
Ok, here's a smile Blendshape. (I somehow lost the hard edge on the middle of the upper eyelidfold, have to fix that later.)


http://www.androidblues.com/smileSmooth.jpg

ashakarc
06-11-2005, 02:56 AM
off topic, I like her ambiguous look, very dreamy, I don't want to see her smiling and earthly ;)

paperclip
06-11-2005, 10:04 AM
If you look at the previous pre- and post- rendered images, you'll see that the corners of the mouth are totally different AFTER smoothing.

I have a feeling this blendshape wasn't smoothed.

Stahlberg
06-11-2005, 02:50 PM
I'm not quite getting that, paperclip... 'the previous pre- and post- rendered images', which images exactly? Are you comparing image 2 with image 5? And you think those two are different somehow? All the images in this thread are smoothed, except the smaller one. ??

ThirdEye
06-11-2005, 02:55 PM
How many faces for the smooth proxy? Also can you tell us something about the SSS effect?

ps shouldn't this go in the modeling forum? :shrug:

paperclip
06-11-2005, 03:36 PM
This model
http://www.androidblues.com/neutralSmooth.jpg

and


http://www.androidblues.com/facescreenSmooth1.jpg
are the same model, right? The corners of the mouth are different in each- I was just commenting to ashakarc that the same difference would probably occur for the last image you just posted.

Squibbit
06-11-2005, 04:04 PM
Hey Stahlberg, since you're like hangin around, could you like
post a little something on how you came up with the texture for
that face and maybe show the UV map ?

Just like, if you got the time n stuff

that end result is pretty sweet :thumbsup:




.

Stahlberg
06-11-2005, 05:56 PM
ps shouldn't this go in the modeling forum?
Maybe, but there was a modeling tutorial posted here by drawdraw.com recently
http://www.cgtalk.com/showthread.php?t=247566
I replied with my opinion on triangles and 5-sides, and then I had to back it up with images, and people kept asking me more questions. Then I felt the thread was getting hijacked, so I started a new one here and moved my stuff to that. I'll see about moving it to the modeling forum in a little while, once they loose interest. :) Anyway, the modeling forum already has a couple threads about this I think.

How many faces for the Proxy? 713. For the Smooth (2 levels) about 11,000.
The SSS is the misss_fast_skin shader, which comes with Maya 6.5

paperclip - okay, I see.

Squibbit - well as you can see the texture is hardly visible, the bump map is strong but it's very close to being just a simple noise all over. I really should work more on the textures, but I wasn't going for ultimate realism, I wanted a bit of stylization. Not sure if it's working though. The UV mapping, it's nothing special, just a cylindrical unwrap.

Phrenzy84
06-13-2005, 12:37 AM
Squibbit - well as you can see the texture is hardly visible, the bump map is strong but it's very close to being just a simple noise all over. I really should work more on the textures, but I wasn't going for ultimate realism, I wanted a bit of stylization. Not sure if it's working though. The UV mapping, it's nothing special, just a cylindrical unwrap.

yeah its quite a well known side effect of using an SSS shader, esp the miss shader. Look at the CGchoice gallery, the guy who did thor, it was a soldier of rome or something like that, great work but he also posted the texture map with when you compare with the final image you can see alot of that texture detail gets washed away.

Stalhberg, i liking your workings, how do you feel about a clean topology, then doing blendshapes for facial expression, taking it as far as your can and then doing Displacement maps for each blendshape?
I havent used this method but for each blendshape there is a differnt displacement with a underlying base. So for example you bring in neutral pose face into zbrush, paint displacement, then go get same model but smiling, bring that into zbrush, apply same displacement, then paint in or away to get best results and use +-average nodes and blendshapes nodes to blend between the two?

I would think that is the best method if you have time for a creature character dunno for a good looking female but who knows, just wondering.

Stahlberg
06-13-2005, 02:28 AM
Yes I think that would be the best way for a creature, if you have time and resources... the way Taron does it. But I'm not sure if it's ideal for a pretty girl, though, because it's harder to make micro-adjustments to the shapes, and because most of the time, most of the skin has to be very smooth so no need for a lot of gnarly displaced geometry. So it should be possible to make it work with maybe just a bit more detail than my 700 polys, and some strategically placed and activated bump maps.

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