It seems that “Mirroring” a layer completely destroys the base level geometry’s UVs on one side.

This puzzled me for 3 days until i realized what was happening.

This breaks the whole import layer geometry work flow. If u have mirrored a layer then export the base geo and high geo…

then do:

import low res geo
import as layer (vertex position) high res geo.

The mesh explodes on half of the model.

However if you were to export level 2 rather than level 1(base level)… it will import fine.

Mirror seems to be destroying the base level uvs on half the object. BUT its not just the UVs. I even tried pasting good uv’s back over the bad UVs in softimage… The result was that it just would not take the good UVs without exploding half of it. So something gets screwed with the geometry that I could not figure out. I just know the “explosive evidence” is noticeable in the UVs on half the model because each polygon will no longer be welded on half the model.

This may be because I had some triangles on the base… but i’m not sure.

Anyone else notice this?

Anyways… All in all, 2011 seems much more stable and nicer than previous versions I beta tested (2009 and 2010)… Its a huge improvement I feel. Good job guys.

never had such issue… are you sure your geo is clean.?
have you tried the mudbox base head..?

if its possible capture a vid and send it to autodesk for bug tracking…
in the help menue --> report a problem

http://www.linkedin.com/pub/christoph-schaedl/6/558/73b

The geo was fine from i could tell.

I just tried to reproduce it with new geometry…

First i tried with all quads

Then i tried na object with mostly quad but 2 tris

Both symmed ok and imported back in ok.

I swear there is nothing wrong with the geometry i tried. Theres no double faces, etc. Its all very clean geo.

Again after symming a level then exporting etc… the uv’s get exploded (each poly uv unwelds)

This si the only sign of anything odd on the geometry and it only happened after symming a layer in mudbox.

some weird settings in the maya import export..?

maybe send the mesh to autodesk for a closer look…

http://www.linkedin.com/pub/christoph-schaedl/6/558/73b

x_rintintin:

I use topogun as well. I was a beta tester for a while on it, and I’ve never had it blow up UVs etc when working with Zbrush.

I think this is mudbox’s doing somehow.

I actually just came to post about another oddity with the Mirror X function on layers. Its mirroring artifacts (sometimes)

I use Smart Rsym in Zbrush quite a bit, and have never had errors with it like this. Mirroring is a key function I would need.

Also slightly related to symmetry.. although a different symmetry.

I noticed that zooming really close to an object while having Mirror X on your brush… it doesnt mirror over. You can actually see the “mirrored brush dot” right next to your brush on the part your zoomed all the way into.

You have to zoom in real close for this to happen.

When you paint, when its like this, its not mirrored over the actual X at all.

Strange behavior.

A.Baroody 06 May 2010 10:49 PM

I think this is mudbox’s doing somehow.

Mirroring in Mudbox is just moving vertices on one side to match up with corresponding vertices on the other side.  So it’s not touching UVs or doing anything complex with the geometry.  But if you post the mesh or a section of the mesh, I’d be happy to examine your issue.

I noticed that zooming really close to an object while having Mirror X on your brush… it doesnt mirror over.

I’m not able to reproduce this.  Can you post a video or series of screen grabs?

I wonder if this might be related to an issue I have with X symmetry when I have the camera between the two sides of the model. Say I’m sculpting the palm of the base human mesh and the camera is in close looking at one palm. The second side is off the screen behind the clip plane. In this case the display doesn’t seem to update properly leaving the box around the active area (the bit you’ve sculpted) visible as you sculpt. In addition to this and worse, the sculpting isn’t smooth, it’s all lumpy and irregular and the frame rate goes through the floor.

it doesn’t do this in tangent symmetry mode (although you can’t use that on unconnected geometry like a pair of gloves).

it’s been the same since Mud2009.

I just posted my problem with the uv’s exploding on one half of my model, and I bet it’s from the exact same thing.  I mirrored the geometry from one eye over to the other before redoing my uv’s.  Now, after doing my uv’s and re-importing, my mesh explodes on one half of my model once I go up one level.  I would say this is definitely a mudbox issue.  Did anyone come up with a solution?

If you want to see a pic, I added one to my other post.

Matt Dragovits
3D Modeler - Maya/Mudbox

I just did a little more testing and I think I know what’s causing it a little more…

I did have two triangles on my model. (one on each side on the bottom of the boots.  In order to active symmetry in mudbox it told me I had to set the topological axis on level two for symmetry to work.  I believe this is why when you re-import your uv’s it looks fine on level one, but once you step up to level two they start to explode.  I don’t know technically why it does this, but this does seem to be a big part of the equation.

Furthermore, if you lay out your uv’s and re-import them, then mirror the symmetry with the new uv’s it won’t explode.  It definitely has something to do with setting the topological axis on level two for a model that has triangles.

Matt Dragovits
3D Modeler - Maya/Mudbox

I submitted the error to Autodesk

Matt Dragovits
3D Modeler - Maya/Mudbox