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perfectly overlapping UVs

Saidin311
polycounter lvl 11
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Saidin311 polycounter lvl 11
I've done some searching around here and the net and putting things like overlapping and uvs in keywords just bring up things dealing with normal mapping and all that jazz.

I just have multiple pieces of a (sub objects) model that are the same and I want them to share the exact same texture space. But the only way I know how to do that is to manually stitch each of the objects how I want them, then manually scale and rotate them on top of each other, zoom in to some extreme and hopefully line up each vertex.

I tried using "copy" on the original piece and pasting the other piece (which has the exact same number of polys and seams in the same spot). But when I paste the new piece it jumbles up all the uvs into wacky spots. So it seems maybe I'm not using this tool properly?

Is there a script, or a tool or something that can just line up uvs for multiple same things automatically?

Replies

  • cholden
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    cholden polycounter lvl 18
    I'm not sure I fully understand your question, but is it possible you can copy and paste the UV data from one model to the other with this case?
  • Saidin311
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    Saidin311 polycounter lvl 11
    Hmm how about a screenshot?

    Perhaps I'm not going about this right from the start. Ignoring the baking aspect of things (since each part is the same I'm simply going to move things off to the side to bake and then overlap everything on the same spot in the unwrap to texture).

    All the spires on this object are exactly the same object. Within the model. I just moved them around and attached them to the original object.

    In my ideal world I'd like to unwrap one how I like, then select the faces of all the other objects and have everything overlap exactly the same on top of eachother.
    Untitled-2.jpg

    Nevermind the weird seams and such at this point.
  • bluekangaroo
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    bluekangaroo polycounter lvl 13
    hmmm I thought I already answered this....not too complicated but I do understand that having some1 actually show you is usually a million times easier than it being told to you.

    Basically all I do is unwrap 1 piece like you did already and then select 'select by element' so that you instantly grab all the faces of any pieces you have copied (IE your spires). Then in the edit UVW window I give the selected element/faces a planar or quick planar unwrap, scale em down and put them in an area where it makes sense and is easiest for me to select in a few moments. Then select the already unwrapped spire piece and right click 'copy'. Select the other spire piece and right click paste. Sometimes it wont copy all the faces. In that case its most likely because there is an unwelded verticy or edge in your original.

    Also, I make sure to have a checker pattern with numbers/letters written on the side so I can see that when I copy/paste my UVS on top each other that they arnt rotated 90 or 180 degrees in the wrong direction. If it ever does this, all I do is undo and then I paste it again until it is rotated correctly
  • Saidin311
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    Saidin311 polycounter lvl 11
    lol Eric, thanks for digging me out again. I couldn't find the post/message which you told me about the copy/paste method.

    I thought I was following things correctly. Following even your methods here this is the result I get.

    Untitled-1.jpg

    The cut-out image is my original piece unwrapped the way I want. And then the piece in the window is after I followed your steps. (My steps also net the weird result)
  • bluekangaroo
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    bluekangaroo polycounter lvl 13
    hmmm wierd....try again!

    i dont know what to say lol....it works for me tho.

    if that method is not working for you AT ALL, then all I can think of doing is to make a clone of your piece after you unwrap it.

    Which version of max are you using? that might be it
  • Saidin311
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    Saidin311 polycounter lvl 11
    It's 2008. I'll keep pluggin away! I thought of that clone idea too. Just means I have to go around placing things again but it would at least ensure the proper overlap.

    Thanks though! :)
  • bluekangaroo
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    bluekangaroo polycounter lvl 13
    np...give it a try in 9 if you have it just to be sure
  • Saidin311
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    Saidin311 polycounter lvl 11
    Here's a question/issue.

    Right now I stitch everything together. I bound a key to stitch selected. (to make it easy)

    So I run through my object stitching all the pieces together and then relax it out.

    Your comment about things being wonky if they weren't welded got me thinking. so I just took a chunk out, detatched it all and then manually welded all the verts together. It was time consuming, but after welding 2 identical pieces together the copy/paste method worked.

    So whats going on here then? Whats the difference between stitching seams and welding verts? Is there a way I can stitch an entire object together and then weld all its verts at once?


    Just to further this a little. There's obviously something wrong with parts of the mesh. I'm not sure how I'm going to fix that, but suffice to say copy/pasting has worked for 3 of these objects, but not for the other 3 (6 sided object).
  • bluekangaroo
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    bluekangaroo polycounter lvl 13
    My guess is max needs the correct information before going : "ooookay I see you have two identical pieces of geometry here, no problem Ill just duplicate the UVS ya got there". If even one vertex/verticy if un-welded, all of a sudden max has no idea what to do

    theres not really a difference between stitching and welding. When you're stitching 2 edges you're essentially welding 4 verticies together

    Im not sure what you mean by stitching an entire object together and welding its verts tho??
  • Saidin311
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    Saidin311 polycounter lvl 11
    Well one answers the other. If there's no difference between stitching and welding then I would never have need for trying to weld after a stitch. :)

    I'll chalk it up to some funky geometry, Not sure where it would have come from its not like these are very complicated shapes, its the low poly version afterall. It seemed to work for other parts of the model though so I pissed max off somewhere.

    It's frustrating when you think your doing something right, it turns out wrong, and it just ends up being something funky with max that I had no control over in the first place.
  • killingpeople
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    killingpeople polycounter lvl 18
    i didn't read the replies, sorry for any repeats. i know of three basic techniques to try, depending on the situation:

    1. delete all other instances, unwrap one, then copy the geo and re-place.

    2. copy & paste UV info (glitchy) select correctly UVed faces, copy, select similar set, paste.

    3. unwrap all, snap and vert align.
  • Tumerboy
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    Tumerboy polycounter lvl 16
    Also, dig up MoP's UV tools, he's got an align select to vertical, horizontal, or both (collapse)

    This is handy when you're in the original position, of having multiple pieces overlapping, and almost lining up but not quite. You can go through, select all the verts that should be together, hit collapse (doesn't weld them) then select the next set.

    Not as easy/fast as copy/paste, but handy none the less.
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