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[Maya] Transfer maps, two different object scales

So, I have my lowpoly object with uv's layed out and my highpoly, but these two have different scales, how can I match them up, so that I can transfer normals?

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  • JackDCaron
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    JackDCaron polycounter lvl 4
    There are a couple ways to do it, but I am curious: Why are they different sizes? Can you just scale one to match manually?
  • Ne0nfire
    Would be great if you can tell me how..
    I just exported the high from zBrush and the low was retopologized in 3D Coat, but I didn't changed the scale..
  • jfitch
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    jfitch polycounter lvl 5
    Press r to use the scale tool and scale it up? Make sure your transforms/rot/scale are all at zero too in the channels box.

    I saw you're also trying to do this in xNormal. xNormal will let you change the scale in the model settings when you import it.
  • oskarkeo
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    oskarkeo polycounter lvl 10
    what software are you using? apart from zbrush? do you have access to maya/max/blender etc?
  • Ne0nfire
    jfitch wrote: »
    Press r to use the scale tool and scale it up? Make sure your transforms/rot/scale are all at zero too in the channels box.

    I saw you're also trying to do this in xNormal. xNormal will let you change the scale in the model settings when you import it.

    Yea, but I thought they have to be 100% same size. I saw the option in xNormal, but how do I figure out the scale factor that I have to use on my low poly?
    I exported my low out of 3D Coat and my high out of zBrush, both time didn't touched scale
  • AdvisableRobin
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    AdvisableRobin polycounter lvl 10
    Bring your low poly and your highpoly into the same scene using some software, whether it is maya, zbrush or 3Dcoat, select your low poly and scale that until it closely matches your highpoly.

    When you go to export the lowpoly make sure that you zero out the transforms. If you don't know how too then google search it for the specific program you are using.
  • Ne0nfire
    Still not working D: What is this.. I imported low with uvs into zBrush, scaled the low that is was pretty equal to high, set scale to 1 and zeroed out everything, exported both.. result same as before:

    There's something weird going on, it takes my uv tile with chest and puts it in there somehow.. by the way I'm using Multi-UV Tiles


    0p2a4wU.jpg
  • jfitch
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    jfitch polycounter lvl 5
    Do you have maya? Can you take a screenshot of your objects next to each other/on top of each other in maya?
  • Ne0nfire
    I did the scaling in zBrush, my high poly has 12m polys, too much for maya:
    They are both overlapped pretty close on the both screenshots

    jqudpjZ.png
  • jfitch
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    jfitch polycounter lvl 5
    That shouldn't need to be 12m polys man...drop a couple sub divisions and bake from that or use decimation master to deduce it.

    Zbrush doesn't really have a concept of world scale, so my guess is you're getting some kind of scaling on export. The map definitely looks like they're different scales still.

    Have you tried baking directly in Zbrush? Do a projection from your low poly mesh to your high poly, increasing sub divisions and projecting as you go (I'd say 3 sub divisions should be sufficient). Then you can bake from the highest sub division to the lowest.That way you know its the right size because its the same model.

    Not everything he says in this is accurate, but you'll get the gist of it.
    https://www.youtube.com/watch?v=xaGMq1YJwio
  • oskarkeo
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    oskarkeo polycounter lvl 10
    Ne0nfire wrote: »
    There's something weird going on, it takes my uv tile with chest and puts it in there somehow.. by the way I'm using Multi-UV Tiles

    Does Zbursh support multiple UV tiles? I didn't think so.

    Regardless, i love that he has hands growing out of his eyebrows and a sixpack on his forehead, even if it is a baking error
  • Ne0nfire
    I already tried to bake in zBrush also in Maya, which didn't worked. I do need 12m polys because of my small details that I have on my hands and feet which you can't see on the screenshot. Anyway the polycount shouldn't be the reason for this problem.. there must be something else I'm missing. I don't know if zBrush support Multi Tile UV, but that shouldn't affect the baking if it doesn't..
  • oskarkeo
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    oskarkeo polycounter lvl 10
    it will if you're baking both sets to 0,0 -0,1 in uv space.

    how are you going to bake a texture into a channel zbrush doesn't understand?

    it looks like you're getting both sets of normals baking onto the same texture.
    I would suggest spilitting the head off from the body and try two separate bakes.
  • Butthair
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    Butthair polycounter lvl 11
    In ZBrush, go to the Tool menu palette. Near the very bottom is an "Export" dropdown.

    There should be something called scale, check to see what value this is and make sure it matches to any scaling factors from external software.

    Assuming you export out as obj, check to see if maya is setting any scale factor on export. Additionally, make sure the scale of the mesh in maya is 1,1,1. If you did scaling and froze transforms then that won't help.

    3D coat may also have similar issues on exporting.

    Idealling, you should be using GoZ whenever possible if your workflow involves multiple software.

    Another thing to try is bring in the unwrapped model and go to ZPlugin>UV Master and try doing a copy/paste of the UV's. It might not work depending if the vertex order was kept the same from 3D coat (i.e. matching to zBrush's vertex order)

    ....aaaannd something else you could do is reproject the hipoly data onto your unwrapped model that you scaled in zbrush using projection in the subtool. Then you can export low and hi versions.
  • JackDCaron
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    JackDCaron polycounter lvl 4
    Zbrush bakes onto multi (UDIM) UV tiles using the multi-map exporter plugin. I'd say yes to the last post. Import you low (UV'd) model, and project for each subdivision until you have all the detail on the clean model. Then bake.

    Also, decimation master should work and keep your little details, that's what it's designed to do. Probably going to make it a lot less frustrating than trying to tumble 12mil polys.
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