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How to fix UVs w/o exploding problems (Maya, Max, Hexagon)

ZBrush Usage Questions
#1

Okay so I suffered way too hard for this thing. Turns out it was so simple.
I’ve tried every single method that was given all over different forums and nothing worked. I’ll just post here all the solutions that I came across.
Hopefully others won’t suffer as much as I did…

This is using Maya 8.5
Basically to fix the UVs, you have to:

  1. Export lowest mesh in Zbrush. **In the Export section in Tools, besure to turn off Grp and turn on Mrg. This will merge the UVs. Otherwise I’ve noticed that all the UVs are seperated.

  2. Import the OBJ in maya. IMPORTANT STEP
    Make sure u go to the Import options, and set “File Type” to OBJ. NOT BEST GUESS. This was the problem for me. I thought Best guess would just solve everything but it didn’t. Here’s a image for u the settings.

    File type Sepecific Options : FALSE THIS SETTING IS CRITICAL!

  3. Now import, fix those darned UVs. Make sure you check em carefully.

  4. Export out. (Default export settings worked fine for me)

  5. Back to Zbrush. On the lowest subd of your model, import in the fixed Obj.

  6. It should load in pretty fast and now to test it, hit Higher Res. If it doesn’t explode, you’re in the clear!

That’s the basic steps basically.
If you’re still have trouble, you should use these 2 methods that graycrump provided in this link:
http://www.zbrushcentral.com/zbc/showthread.php?t=47336

If those things STILL doesn’t work, another solution is to:

  1. In Zbrush, set your model to the lowest settings
  2. Click Morph Target (In 3D Model tab) > StoreMT
  3. Export out the OBJ, *Remeber Mrg on and Grp off
  4. Import to Maya Remember the settings up above. Fix the UVs
  5. Bring it back to Zbrush at the lowest subd.
  6. Import the model at the lowest subd.
  7. Go to Morph Target > Switch
  8. Try putting it higher rez and it should work.

Whew… If it still doesn’t work… I don’t know. You’ve got alot of researching to do. haha… Goodluck and happy modeling! :cool:

edit I do not take credit in any of this. All these solutions were suggested by other users and I just came across alot of them. I thought it’d be better to bring it in all at once.

#2

Wow, am I glad I found your post. This import thing into maya was the thing that made me go berserk :eek:
Since I use the sculps as blendshapes point order is crucial for me and now it works! Thanks to everybody who contributed! :smiley:

#3

man, you saved it! those maya setting were killing me.

thanks.

#4

Thank you SO much, I had gotten this process working with max but I haven’t yet with maya, UNTIL NOW! I can’t thank you enough for the trial and errors you must have gone through, I know what it’s like. Thanks.

#5

i noticed you said you know how to do this process with 3d max, im having this explode problem can you please tell me how you do it with max. my models got to be done by next week and this is driving me crazy!thanks

#6

Going from memory ( mind you I did this about 3 months ago so it probably wont work, and I was using zbrush 3.0 not 3.1 ) but! ill post the rough process anyways.

step 1 - in zbrush3 - export lowest res as an obj

step 2 - in 3dsmax - import obj file and lay out uv’s

step 3 - in 3dsmax - export geometry as obj .

step 4 - in 3dsmax - import the geometry you just exported from 3dsmax, back into 3dsmax.

step 5 - in 3dsmax - export from 3dsmax as an obj file. ( you must export the file from 3dsmax 2 times , something to do with vertex orders or something.)

step 6 - zbrush 3 - open file in zbrush and export it AGAIN! as an obj file. ( again something to do with vertex orders.)

step 7 - zbrush 3 - open the hi res model without uv’s and go to lowest sub-d level.

step 7 - zbrush 3 - import obj with uv’s, and under the morphtargat sub menu under the tool palette click the button named switch ( Tool > Moprh Target > Switch *the name morph target could be off, just going from memory here

that should switch one low res for another. Now mind you im just going from memory here, and after a lot of testing and experimentation i did get it to work for zbrush 3.0 NOT 3.1 so if it still doesn’t work, im really sorry. My friend and I found all of this out and im pretty sure he has a psd file documenting the entire process with screen shots on layers, sadly he’s gone to korea to teach english. If i can get in touch with him ill see what i can do to hook you up buddy. Hope this helps, let me know how it turns out too. just remember to export it from max twice, and then again from zbursh, thats important. and really long and annoying haha. GOOD LUCK!

#7

By Export It From Max Twice You Mean Export Then Re Inport Then Export Angain. Or Simply Export Then Straight Away Export Again?? It All Sounds Far More Complicated Than It Should Be,lol, Ill Give It A Shot Thanks.

#8

haha yeah it IS way too complicated. It’s just it’s the only way I’ve gotten it to work before I stumbled across this thread for a way to do it in maya.

by export it twice i meant, exporting the obj 2 times from max.

ie… file>import , file >export / new scene / file>import , file> export

#9

i did as you said and i can now go through the subdivisions with it working, but when i go to check uvs my whole face turns black, is this right? do i need to flip them or something?? i hope im nearly their, been doing it all day

#10

f*@k, it actually works! thanks you so much, sorry for language but i am so relieved, i did exactly what you said but also made sure the export options stated in that other tutorial are the same ( turn mrg on grd of) thank you so much. by the way looked at the pic you did in your gallery is that a full 3d model?? it really really good.

#11

Sweet dude! I’m so glad it worked out for you. You should take my step by step instructions and add in what you found out. Just so it’s on here in this Thread in working order for everyone to come back to if they run into similar problems.

As for my model,yeah it’s all 3d, haha and thanks a bunch I really appreciate the praise. If you have any questions just drop me an email. My e-mail is on my website in the contact section ( mail Icon )

Again, I’m really glad I could help out dude, nothing worse than a deadline with a huge technical hiccup.

#12

this is how you export your mesh to 3d max for uvs and bring it back to zbrush without the mesh exploding

  • in zbrush make sure the export settings are set to mrg on and grp off (very important)

  • goto your models lowest subdivision and export

  • load 3d max and import your model (make sure you select single not multiple objects in the settings, very important), i also unselected the import texture coordinates but dont know if that makes or breaks this process

  • do your uvs, a good tutorial for the ideas behind doing this is by eric masowski, search for eric masawski organic modeling in google and you will find it. (make sure you dont move or edit anything other than uvs on your model, as this alters the vertex order)

  • now export the model with texture coordinates, use name such as model export 1 so you dont get confused on the next few steps

  • now open a new project in 3d max and reset it, then import the exported model you just did (make sure texture coordinates are still on and its single not multiple objects.

  • then export it again (same as before), this time name it model export 2

  • open zbrush and import the obj you just exported from max

  • export it again, again make sure mrg is on grp off

  • i then closed zbrush, re opened it, loaded my high def model, turn that down to lowest subdivision (this should be the one you original exported at)

  • now import your just exported model from zbrush. this should now work when you go through the division levels. select uv check just to double check its applied your new coordinates. (they should appear in the texture panel on the left, i think no red areas means no overlapping which is what you need.

their you go, sorry for the amount of stages its just i wanted this to be as easy and basic to follow as possible as the last thing you want is for you to spend all day doing the uvs and then it still not work.

i dont take any credit for this, this was just a mix of two other peoples methods mixed and a bit of trial and error.

#13

Thank you for the walk thru for 3DS Max. I followed it exactly and it almost worked perfectly. I say almost because I got some geometry from my ear that intersected the whole head into the mouth. I can’t figure out why it’s doing this. I even tried doing a morph target, but that didn’t work. The only thing that I found about this area of the ear is that it has 1 triangle right next to the poly that explodes. My goal when redoing the topology was all quads, and it looks like I missed one. So if anyone else follows this method and runs into some weird stuff, check if there’s a tri in there.

I’m gonna start the unwrap process over and see if happens in the same spot again.

#14

how are you changing the topology in 3d max without altering the vertex order? i don think you can ,can you? because you would have to mess around with the vertices to create quads? i really don think it is because you have triangles as my model unfortunately has a few triangles on the ear (tricky thing to model) and it works fine. what you could check is that you dont have any overlapping or inverted areas on your uvs, i dont know if it has that effect but i know the tutorial i was watching said you will have a lot of problems if you have them and you want to take your work into zbrush. im only new to zbrush but id say check that first as its an easy thing to fix to test.

#15

Thanks to everyone who did the heavy lifting on this one already! :slight_smile: I will be importing my new uvws from max tonight and this info will undoubtedly save me loads of
trouble. Thanks again to all involved!

#16

I sculpted the initial shape from a PolySphere, and then did the topology in ZBrush, then sculpted the higher details. I then exported the lowest level, and followed the instructions for importing/exporting for max.

If I would have used max for the topology I would have had way worse results than just a single area messing up. Again, the only thing about the area exploding is that there’s a triangle there. Can’t say this is positively the reason for the problem, but it’s the only thing that is different about this area on the model.
What I don’t get is why the morph target is not working with it since that’s supposed to take UV’s only, and not the geometry. And there’s no overlapping or messed up UV’s. I’ll try to get a snapshot of what I’m talking about later.

#17

I was having the same eploding issue with Hexagon for creating new UVs on my Zbrush model. It was reordering everything, so after importing and trying higher subdivisions, it exploded.

My method is pretty simple and worked twice for a simple shape made with 3 zspheres and high poly detail applied. Don’t know if this will work for any application or has draw backs.

  1. I export the lowest subd from Zbrush, it has no UVs at all, no polygroups either.

  2. Import it into Hexagaon with default settings if I recall. Create the UV map. Export it as object file (again, this file is bad as it will explode).

  3. Open UVMapper. Load the original untouched Zbrush Object. Import UVs from the bad Hexagon object file. Save it as a new object.

That was it, instead of using the bad hexagon file, I used UVMapper to transfer the UVs to the Zbrush object file. So importing it back into Zbrush it doesn’t explode, and the new UVs work perfectly.

Here’s the simple test I did, rendered in Carrara with the 2048*2048 displacement map I was finally able to make, subdivided 6 times at render. Includes zbrush image, lowest polygons in Carrara, and final render:
http://other.toonguru.com/3D/displace_test.jpg

I finally feel like I’m getting somewhere with these programs working together.

Now comes tougher part, maybe my method won’t work with a more complicated UV map compared to this simple shape I did. Anyone know any drawbacks by doing it this way?

#18

wish my programs would work right

#19

I just came across the very same ‘exploding re-import’ problem; the solution was to export the mesh WITH UVs from zbrush. So I had to create some default GUV/AUV or whatever, and check ON the ‘Txr’ switch under Tool>Export.

You may not leave the UVs blank when exporting, that’s the deal. I guess. :wink:

#20

Hey guys, I got a question…(I am using ZBrush 3.1 and Max 8). I followed the aforementined steps for importing new UVs and worked fine the first try. Nice. Now, while working on the model with new UVs (7 subdivisions, system w/ 4Gb of RAM & dual processors), ZBrush crashes once every half hour or so for appearently no reason. Just closes. I’ve been working on this model for quite sometime, and I’ve had alot of crashing issues already, but they were usually always when saving or working on the highest subdivision level. These new crashes are just random and frequent. I’m guessing it might have something to do with the new UVs. Anybody else have an excessive crashing while working on a model with new Uvs issue? Is there any sort of way to “clean the history” of the model? Just wondering…