ZBrushCentral

Trouble exporting painted obj back to max 9

ZBrush Usage Questions
#1

Sometimes it works…other times far from it!

I have a mesh from Max 9. An unwrap modifier on it. No overlapping uv’s. NO major distortion when fixing the overlapped uv’s.

I export out obj…quads…well I know my exporting is correct. There is something in my mesh that Zbrush doesn’t like.

I import the tool. Divide the geometry. Go to Texture - new set to 1024 by 1024. I go to Texture and hit “colorize” then hit “Txr>Clr”

I change my material and begin painting. All goes well so far. Then I hit Clr>Txr and small streaks appear on the object (they kind of look like the poly edges from my mesh but it is hard to tell as they only appear in certain places, not everywhere.

And the little texture patch on the left side of the screen looks all staccatto or broken up…it does not look smooth.

After going into Photoshop and flipping the image vertical and going back into Max and applying it to the original mesh there are black triangles within each poly.

I have three bean-characters. All very similar in construction. One of them goes through this process perfectly. The other two fall apart in the manner I described.

I am assuming I have UV problem but in checking the mapping in the unwrap editor in max, it looks pretty darn good. Very little difference in the way the three bean characters are unwrapped.

I cannot figure out what is wrong. I know Zbrush doesn’t like max very much but I hate to give up.

Does anyone have a clue as to what I might look for in my mesh?

I have done the proceedure from max to Zbrush and back more than a hundred times so I know the proceedure I am doing is correct so the problem must be within my mesh…but darn if I can find out why.

thanks for any help

#2

Sorry I can’t help.
Just wanted to mention I’m getting the same problem with some Mesh I’ve been trying to work on.

There are several elements seperately mapped in it which I later devide into subTools in Zbrush. One of the subtools gives the exact same erroneous result - a UV map in which Quad’s are devided into their two Tri’s, one of which remains in the correct color, the other black.

The mapping is fine. When I try reimporting the OBJ into max directly after exporting it, the UV is perfect.
It’s the importation to ZB which causes the error, as far as I know.

#3

If your texture looks triangular like you describe, (half of each poly missing), then there are two possibilities. Both are in Max.

  1. Make sure that # of Digits is set to 6 in the OBJ exporter.
  2. Try resetting the XForm
#4

Thanks Aurick. Seemed like I forgot to reset Xform for that specific object.

By the way, I`ve always known to set the digit number to 6 but never actually understood the logic behind it. Could you give it a minute to explain?

#5

Aurick, here is a jpeg of the problem. I did the reset Xform. The # of digits is set (and was set) to 6.

Funny that the Reset Xform flipped my polys. So I collapsed it to editable poly and reflipped the polys…just thought I should slip that in here in case that implies something else. I also did the Reset below the unwrap modifier in the stack.

Here is a screen grab of the process.

1 - a view of the mesh in max
2 - a view of the unwrap edit window - I did not include a snapshot of the template but there are no overlapping polys…I corrected those.
3 - the exporter window showing the settings
4 - Zbrush 3 showing the stripe of paint and how clean it looks. (this is not how I intend to paint but didn’t want to waste my time if there is a problem in the base mesh.
5 - Zbrush 3 after clicking Clr>Txr
6 - Image map in Photoshop - flipped vertical
7- back in max with the image applied

So the reset xform did not change the results. this is eactly what I got before.

I have another bean character that looks very similar to this one but the problem does not occur and it goes through the Zbrush process like a dream.

Hope you, or someone can see where my problem might lie.

Thanks for taking a look and trying to help.

Attachments

distortionExport.jpg

#6

This will probably won’t help your case here (I haven’t seen the triangle effect before), but it might be worth knowing?

I’ve hade problems in ZB2 in the past if I use pack uv in the UV unwrap mod. Even though it looks fine in max, zb2 always used to give me problems with the texture and uv’s. If I used pack uv’s all I had to do to fix it was select all the uv’s and scale them down very slightly and back into zb and it would work fine.

Good chance you know the below already.

Max 9 editable poly has some major problems with retaining all the previous modelling info and creating huge file sizes (known bug), you could also try convert to edit mesh, back to editable poly, reset xform, export as obj.

Or merge your base mesh into a fresh max scene and try again, taking into account that the max file might have become corrupted as it does sometime for no apparent reason and your other file works perfectly.

Delete your 3dsmax.ini file and restart max, this can also fix a currpted max. Remember that this will wipe all your custom short cut keys, viewport colours, quads etc. So you might want to save these out before hand.

That is if it is a 3dsmax problem and not a ZB3 one.

Ben :wink:

#7

thanks for the tips…well worth a try. Would be nice to circumvent having to completely rebuild…though they should be rebuilt as I have found some limitations that might cause problems down the line.

To convert to editable mesh would force me to lose all the unwrapping I did…I think. But I can save under another name and try it.

Thank you for your suggestions. Very much appreciated.

#8

Michael, please let us know if you manage to overcome this and how you did it :slight_smile:

Good luck! We will pray for your beans. :cool:

#9

the beans are grateful for the prayers. Hehe!

Tried all the above but looks like it is not do to a corrupter file but a corrupted modeler…me.

Using Topogun to retopo the mesh. Eldee.s told me there was a way inside Zbrush to retopo but he is traveling across the mainland right now.

Thanks again. If I find a fix I will post what I did.

#10

The Wiki is your friend. How to retopologize a mesh in ZBrush 3: http://www.zbrush.info/docs/index.php/Topology

#11

i don’t think converting to mesh would trash the uv’s- add an unwrapUV to check anyway
you could try polygons instead of quads in the export/import
good luck

#12

Thanks Aurick, I will check the Wiki.

As far as the not losing the Uvs when converting to edit mesh…unless I add an edit mesh to the stack…converting collapses the entire stack.

I will try the edit mesh or edit poly into the stack. This is a wierd problem.

Thanks for all the help you folks are providing.

#13

If you collapse the mesh with the UV Unwrap on it, the UV’s are now baked into your mesh (until you modify the UV’s again). Try it, then put another UV unwrap mod on top, if you enter into UV edit mode you can see that your UV’s are still there.

Same goes for the reset XForm mod apply it to the meshs stack and collapse to editable poly, then export from max.

Just clarifying skylertonne is suggesting trying Polys, in the OBJ export dialog instead of Quads.

#14

You guys are terrific! Thanks Scratchy. I never knew that. funny that I should learn so much about max on the Zbrush Central forum. Thanks again.

Regardless of whther I can troubleshoot my uv problem…all the tips I am learning here are going to shave hours, if not days, off my workload.

thank you all again…and again!

Once this goes into production…I will need to subcontract work out to you.

#15

I too have the same problem and after weeks of messing with the my mesh I haven’t found the solution.

#16

voyeur,

I Had trouble logging on to the forums here…

The problem I had was from overlapping polys in my UV mapping…when I used to do it in Max. I bought the program UVLayout from Headus and I have not had the problem since…it even makes setting up the UV’s fun!

If your problem is more than this…something like you cannot get Zbrush 3 and Max to shake hands…let me know the steps you are using in both programs and maybe I can spot what is wrong. I had lots of help here in learning how to do the painting in Zbrush and getting it back to Max.

#17

Yeah that might be the solution but, I cant seem to correct it, the over lapping uvs I mean, its happened to me twice. I will post pictures once i get home and a step by step of what I did.

#18

The problem hasnt been sloved and yet again foils my plans :open_mouth: