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How to subdivide a partly triangulated mesh.

ZBrush Artworks
#1

I have imported my model but when I sub divide my model who’s head had to be triangulated for optimization :< (dont know of any quad poly optimiser feel free to tell me) When I subdivide in Zbrush 1.55b to add detail and smooth it the head gets really screwed up as it gets little mesh deflects and the topology looks weird. I know how the subD’s work as they work like normal subd’s in any 3d package but the sub divide and the smooth elements are seperate.

However when i subdivide my imported .obj the topology doesnt seem to be right…

Also there are no loose vertecies anywhere. The model is clean from top to base…

Any help here would be hot!

The Images:

Cheers guys!

#2

Hi subspark
I think if you export and reimport your object in ZB the proGram will try to fix it because by default it uses quad poli instead tri poli.
I hope this help
Andreseloy

#3

I’ve worked succussfully with models that have a few tri’s, but nothing like you have there. I have found it best to plan ahead if you want to use ZB for texturing/detail modeling, and use all quads in your model. You have lot of tri’s in areas that I think could be optimised a bit, like the ears and nose area. Maybe try converting everything to quads before you import this model into ZB.

Here is an example of how I used an all quad low poly model for detailing and texturing. Maybe this will give you some ideas. The low poly model ended up with about, 1,200 quads, or 2400 tri’s (after conversion). High poly model is about 80,000 quads. Same UV layout space though.

Low Poly

High Poly

If you have any more questions about this, ask away!

Chad

#4

Cheers mate. Im optimising already however I still don’t get why a dozen more tri’s would chew up the mesh like that on Smoothing. I wonder if my export from Max was a bad idea. Maby ill try exporting straight from Maya. Darn I’ll have to install it all over again…

Thanks anyway guys…

#5

Hi wchamlet
Please, let me know how you get this map from you low and poli object?
Thanks
Andreseloy

#6

“Im optimising already however I still don’t get why a dozen more tri’s would chew up the mesh like that on Smoothing.”

because of the algorithm. for subd you should be using quads, sometimes you can sneak a tri in but it might have to be changed, so stay away from them as much as possible.

#7

If you have maya, which it seems that you do, convert your triangulated model to a subdiv then convert it back to a polygonal model using adaptive tesselation, 1 division per face. You’ll end up with more polys than when you started, but they will all be quads and you can tweak from there.

#8

3D Studio Max (my native program) seems to have a more up to date and more effective or flawless algorithm for subdividing models. As you all probably know and have seen or done yourself, most lowpoly models for games have a combination of quads and tri’s and even in the hi end modelling process your model will most likely contain a fair few tri’s on a mostly quad mesh. Its the way I work. Now when I subdivide in 3ds max or Maya the tri’s dont seem to chew up the mesh therefore the software seems to have a better algorithm for subdivision.

One question: Please Pixolator give me a hint, will the new Zbrush have a better or flawless algorithm for subdividing?

Gee I hope so.

Cheers all. Guess I’ll have to wait “sigh” or use maya to quadranglate my model.

#9

The question that I have first is: Are you going to be using this mesh in ZBrush, or do you intend to take it back to Max? If you will be using it in ZBrush, then it doesn’t matter what you do to the mesh and life is easier for us. If you plan to take it back to Max, does it need to remain tris? I’m guessing not or you wouldn’t have tried dividing the mesh, but I want to be sure.

If you plan to take it back to Max and need it to remain as triangles, then you shouldn’t even mess with any of this stuff. Just sculpt it as triangles and make sure Tool>Modifiers>Smooth remains set at 0 (or set it to .01 if you are using TextureMaster).

If the polygons don’t matter at all, then here is an option:

  1. Go to Tool>Inventory and maximize the Tris2Quads setting, then import the mesh using the import button there. ZBrush will then attempt to combine triangles into quads as much as possible while importing the mesh.

  2. After that has been done, the Tool>Modifiers>Deformation>Divide button should work better. You will most likely want to follow it up with the Smooth deformation in order to average adjacent vertices and get a smoother mesh.

The reason that you are having problems in your example is simply due to the poly arrangement in your model. Those puckers are happening wherever the mesh has a high number of polygons connected by a single vertex. If the tips above don’t work, you’ll need to use a non-ZBrush conversion method or restructure your mesh.

#10

<BLOCKQUOTE>quote:</font><HR> Hi wchamlet
Please, let me know how you get this map from you low and poli object?
Thanks
Andreseloy <HR></BLOCKQUOTE>

I explained how to make the UV layouts in this thread here.
http://www.pixolator.com/zbc-bin/ultimatebb.cgi?ubb=get_topic&f=1&t=013993

It’s really not very difficult. Just make your low poly model, assign AUV tiles to it, export it out. Import that model back in, and DO NOT adjust the UV’s in the texture palette. Thus, when you divide your mesh, all of your UV’s will share the same space as the low poly model.

If you are meaning how I got the screenshots of them, then I did that by capturing the UV editor in Maya. I decided to use AUV tiles for this test because I am finding out that it is indeed one of the most impressive features of Zbrush. So I’m going to force myself to learn to paint all of my textures using this technique, because quite frankly I think it’s a huge time saver. I don’t like laying out UV’s by hand! LOL

I Hope this helps.

Chad

#11

Hi wchamlet
Thanks very much for your attention¡
Andreseloy