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Greenlaw
05-10-2019, 10:47 AM
Hi,

I'm not sure what the proper terminology for this is but does anybody know if there's a way in Modeler to merge polygons in a subdivided mesh to get you more or less back to the original mesh before it was subdivided?

Years ago I used a third party standalone program for this but I need to do this natively in Modeler now.

Thanks in advance for any useful help or suggestions.

(Oh, and what is this process called anyway? Un-sub-d?) :)

Greenlaw
05-10-2019, 10:56 AM
Here's what I actually need to do: I want to render a wireframe overlay to comp over a normal render but the mesh is too dense and I want to reduce it. I also want the polygons to have the same or similar flow.

So, if I can do this as a surface/render trick, that could work too.

Danner
05-10-2019, 10:58 AM
Blender has a modifier called "Decimate" and in it it has the option to "Un subdivide"

Greenlaw
05-10-2019, 11:00 AM
That's good to know. Thanks for the tip!

Unfortunately, we don't have Blender in the studio. Is there something similar in Maya?

Greenlaw
05-10-2019, 11:12 AM
Hmm...I just read elsewhere in these forums that a mesh can be sent to ZBrush and, if the polygons all quads (which this mesh is,) it's possible to reconstruct the mesh at a lower sub-D level.

We do have ZBrush here. Will look into that.

Greenlaw
05-10-2019, 11:18 AM
I think ZBrush's ZRemesher might work for me. Here's a video with the steps if anybody else needs this:

https://www.youtube.com/watch?v=_ips3GhWI0s

raymondtrace
05-10-2019, 12:12 PM
...Unfortunately, we don't have Blender in the studio...

I'm sure there's much more to this story. However if one needs a no-install version that does not leave anything on a system (nor require admin rights to run), consider portable Blender.

https://portableapps.com/apps/graphics_pictures/blender_portable

It is a great companion to a portable Lightwave.

Greenlaw
05-10-2019, 12:37 PM
Thanks but, unfortunately, that won't be possible where I work.

Also, the ZRemesher trick almost worked for me but not really. I think the mesh is just too complicated and I don't have the time to break it apart. Decided to take a different, simpler approach altogether.

Oh, well...at least I learned some new techniques for my personal 'bag of tricks' today. Thanks guys! :)

Greenlaw
05-10-2019, 04:30 PM
Took another look at this in ZBrush. D'oh! Using wrong tool. I did a quick test using simpler geometry and found that Reconstruct Subdiv is the tool that does what I needed.

No longer need this now but I'll know better for next time.

erikals
05-10-2019, 04:41 PM
i do it in Blender
https://www.youtube.com/watch?v=dObKKXbRehE

Greenlaw
05-10-2019, 04:55 PM
Nice! Thanks Erikals, I'm going to try that at home tonight.

I'm guessing there may be a legal reason we don't have Blender here. The studio is (rightfully) very particular about EULAs and licensing for everything, commercial or Open Source. But I'll ask. IMO, when it comes to software, you can't have too many options.

BTW, for the ZBrush test I did a few minutes ago, I just Go-Z'd the geo from Modeler to ZB, selected Geometry > Recontruct SubD, and it just worked. Then I just sent it back to Modeler. I didn't see any options but I didn't spend a lot of time with it either and I haven't tried this with anything more challenging yet. Will play some more at home this weekend.

erikals
05-10-2019, 07:36 PM
even though i don't own it, i've seen some nice Retopo/De-Res stuff in ZBrush, so definitely worth using.  https://i.imgur.com/bcwLfNX.gif

would also like to give Houdini a shot in terms of modeling features. but on hold for now.

Greenlaw
05-10-2019, 07:46 PM
Oh, that's something I should look into. Studio just installed Houdini on my box the other day. Unfortunately I have almost no experience with Houdini...yet. (Mostly from from watching other artists I work with using it.)

erikals
05-10-2019, 09:28 PM
love parts of it, but too "Nodie" in many many cases. however, for VFX... it is Awesome  https://i.imgur.com/JsBiFVj.gif
+some other things.

by the way, not what you need perhaps, found it cool never-the-less


https://www.youtube.com/watch?v=dVeE1ggo0Lg

Sensei
05-11-2019, 12:54 AM
Here's what I actually need to do: I want to render a wireframe overlay to comp over a normal render but the mesh is too dense and I want to reduce it. I also want the polygons to have the same or similar flow.

So, if I can do this as a surface/render trick, that could work too.


You have EasySpline (http://www2.trueart.pl/?URI=Products/Plug-Ins/EasySpline), if I recall correctly. You bought Modeling Pack in 2011.
There is tool Trace Spline. Select two points on your dense mesh, use Trace Spline. Repeat.
After a while you will have spline cage which looks like your original mesh.
Then you can use EasySpline to regenerate mesh with wanted precision.
With Spline Density you can regenerate splines to wanted precision.


https://www.youtube.com/watch?v=xtZUKmiltqY

erikals
05-11-2019, 03:58 AM
yep, worth a note.