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ZBrush differences in global scale between Tools

CharacterCarl
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CharacterCarl greentooth
I understand that ZBrush is not very prolific at handling exact measurements (centimeters, etc.) as it uses its own system.

However, what has been bugging me lately is that, apparently, someteimes there's a different set of scale used for certain Tools/models which shows in the changing of brush sizes as demonstrated below (female base mesh by Eugene Fokin):

2IVfJxu.jpg
yTb1Awg.jpg
6lNAtvD.jpg
YhRsFgU.jpg
8ro8jgx.jpg

Appending the small Subtool onto the big one bears the same results, just the other way round (brush stays too big, even after deleting the bigger SubTool). "Unify" resolves the issue.

I hope that this is not just a special case with Eugene's base mesh. :poly136: It exports nicely into Maya with the scale intact, which never happens for anything I import over from ZBrush, ever:

c9nchCn.jpg

Models always turn out too small, but when scaled up and brought back into ZBrush the brushes always behave weirdly.
Is there something I'm missing? How do you handle size issues between ZBrush and other apps?


TL;DR: Is there a way to change the global scale of a Tool inside ZBrush?

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  • m4dcow
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    m4dcow interpolator
    So there is no way I know of to change the global scale.

    When you import a mesh into zBrush from what I can tell it makes a bounding box that encompasses the greatest magnitude axis and then uses that for its coordinate system. This affects how the brushes work etc... When you append to a tool, the appended tool inherits the bounds of the tool it is being appended to. So if the actual scales are off by a lot, you will have the issue you do.

    GOZ doesn't help, because the bounds are maintained when you bring the mesh back in. You could try scaling in maya or whatever you use, and then export as an obj and import into zrbush from scratch.
  • CharacterCarl
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    CharacterCarl greentooth
    I see, you're right. Well, sometimes I change the unit system inside of Maya to meters which helps a bit with models that are too small but other than that it's manual rescaling.

    Not that much of a deal if I stay inside ZBrush for most of the process. However, there comes a point where working close to "real" scale becomes beneficial:
    For example when baking (otherwise I'll need to adjust the scale inside xNormal) or if I'm testing assets inside a game engine and want to add the high poly details later on.

    How do you deal with this issue?
  • m4dcow
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    m4dcow interpolator
    I don't really deal with characters much, but I keep Maya units in cm and create my objects based on whatever scale they will be in engine, and don't really have any issues beyond that.
  • CafeNight
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    CafeNight polycounter lvl 5
    for avoid go to preference - draw and change max brush size and dynamic brush size
    and use Dynamesh Master this plugin work differently as Zbrush Dynamesh
    its just how to deal with it in zbrush you can't change global scale as say it before
    and just work part by part so there is no problem I belive

    well you still can use real scale just be careful
  • CharacterCarl
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    CharacterCarl greentooth
    Had to dig this up again just to show that it seems I've finally found a solution to my problem.
    I apologize if the way I posed the question was slightly confusing, but, as a matter of fact, all I was looking for was this slider:

    RJZFM7n.png

    All I have to do is keep this synchronized with the way I scale my model in Maya and everything works fine.
    Note that this doesn't just affect export but import as well (low poly on the left was imported)!

    Hope, this wasn't too obvious and actually helps someone. :)
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