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High to Low Texturing Workflow

Hey guys,

I'm going from a high rez sculpt in zbrush (no UV's) to a low rez mesh.

How would I go about getting the poly paint data from a high rez mesh (no UV's) to the low rez mesh (with UV's)?

I have tried to do a method that involves XNormal.

  1. Taking the high rez (polypainted)
  2. Making a blank texture map for it
  3. Generating GUVTiles
  4. Hitting New from Poly paint (poly paint is scene using GUVTiles)
  5. Taking the low rez and the high rez into XNormals
  6. Baking out the base texture from the high rez to the low rez
This works good, HOWEVER -- I am getting artifacting across my model (because of the GUVTiles being constructed of lots of little...well...tiles), and it's not as clean as I hoped.


What is a high poly paint to low rez workflow? Thanks!

Replies

  • passerby
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    passerby polycounter lvl 12
    just export out you polypainted high poly from zbrush, and bring it into xnormal, uncheck ingnore vertex colour on it's entry and in baking options check off bake highpolys vertex colour.

    make sure to set a good ray distance or setup a cage too.
  • SpeCter
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    SpeCter polycounter lvl 14
    As far as i know you can export the high res with polypaint. xNormal can read that out.

    edit:passerby beat me to it
  • krazypoe
    Thanks for the replies, I guess my next question is --

    My model is 54 Million polys and trying to export the model as a whole crashes my system -- How would I go about poly painting a model that has many different subtools, and then taking it and baking it using Xnormals onto a retopoed mesh of my model?

    If I exported the model in "groups" (so I can actually get it out of zbrush) -- when baking it using XNormals -- will I just have to do a couple of bakes and then take them into Photoshop, and combine them?
  • passerby
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    passerby polycounter lvl 12
    xnormal can take multiple high polys.

    so just bring them all into xnormal
    or try using decimation master.

    xnormal dosnt need to draw the model, so as long as you got enough ram, xnormal should be able to handle it all.
  • krazypoe
    passerby wrote: »
    or try using decimation master.

    When using decimation master on a subtool that has poly paint information on it, doesn't that destroy the poly paint because it's based on verts?

    Thanks again!
  • cryrid
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    cryrid interpolator
    Definitely use Decimation Master to try and reduce the file size; it should be able to preserve the detail and polypaint while drastically cutting down the number of polygons. You may even want to do a small test to see if the texture size you're aiming for would even be able to maintain all that detail in the first place, or if you're free to step down a subdivision level without a noticeable difference in quality.
  • krazypoe
    cryrid wrote: »
    it should be able to preserve the detail and polypaint while drastically cutting down the number of polygons..

    I did a small test where I took a poly painted sphere -- then decimated it -- the poly paint just disappeared. Is it hiding somewhere or am I missing something?

    Thanks for the replies!
  • cryrid
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    cryrid interpolator
    I would check to make sure polypaint is enabled, because it should preserve it if such data exists.
    dm_polypaint.gif
  • krazypoe
    I checked and under the Polypaint menu > Colorize was enabled. Yet when I decimate, the information disappears.

    Hmmmmm :/
  • cryrid
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    cryrid interpolator
    Go under Preferences: Decimation Master. There is an option to use and preserve Polypaint
  • krazypoe
    Upon trying to look up more information I saw your other post LOL

    http://www.polycount.com/forum/showthread.php?t=84917&page=2

    -- I didn't give my high rez generated UV's or bake the poly paint to the texture, or have DM preserve the UV's.

    ..........NOW I KNOW ! :D

    Thanks
  • cryrid
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    cryrid interpolator
    Past me was misinformed.
  • krazypoe
    After following those instructions though, I seemed to get a little bit of stretching on the poly paint upon decimating.

    Hmph.
  • krazypoe
    Oh... haha XD

    Well isn't this an interesting sequence of events.

    *UPDATE -- Baller, seemed to keep everything in place thar.
  • gray
    assuming you have one big mesh that is the problem. you can extract your maps by working in sections. this keeps your original highres mesh data intact.

    1) first model your lowres cage and do the uvs.

    2) now define two or more regions of your model based on uv seams.
    easy way to do this is just to assign a different shader to each region. you don't need to cut the model, just define some regions where the uv tiles from each region connect.

    (example) region one is all the uv tiles that make up the head and chest, region 2 is the hips and legs etc.

    3) in zbrush cut your highres model into pieces that match your lowres regions but overshoot the lowres region a little so the lowres is smaller then the highres. so along the border of each lowres region there is still some surface from the highres.

    4) export each lowres and highres region and extract each set of maps.

    edit: generally you can just use your full lowres without cutting it.

    5) now you can composite all your region maps in photoshop and have your full lowres model map.

    just make sure you keep all your seting the same when extracting the maps for each region.

    and if you have many different subtools you can generally use the same concept. just find places where you can group objects instead of tiles.
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