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Baking single mesh with one area adjacent to another

Hello there.
I have a question regarding baking of a mesh with areas that are situated very close to each other. For example, a robe with a hood, where the hood touches the back, so to say (to show what I mean attaching a example from hogwarts legacy). So the whole robe is a single mesh so don’t think exploding is the way to solve the problem. And I guess there’s no way you can  adjust the cage so it saves you from baking issues. 

So my thoughts on it are:
The first possible way – cut the hp, cut the lp, bake separately the main part of the robe, and the hood (both having corresponding hp and lp parts) then combine maps in photoshop. 

The other – use layers in zbrush. Rotate the hood of the high poly at a certain degree. Then retopo the robe. Get the hood of hp to the initial position. But then how to sync it with the low poly so it matches hp perfectly. So I guess that’s not the way. Or I’m missing something here.

Actually, that’s not only about the hood, but same question arises when I think of baking collars that cling to shoulders, lips area with mouth closed, any tight places really.

I’d really like to know how such situations are handled on real projects in studios. 

Appreciated for the help in advance.


Replies

  • Benjammin
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    Benjammin polycounter lvl 6
    In substance painter, you have your highpoly and lowpoly separated into pieces within a single fbx file. Then, if they share the same name with the right suffix (_low/_high) they will bake separately without any need to combine maps in PS. In the case of clothing, if you separate it into pieces where real sewing seams would be it'll be fine.

  • dimwalker
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    dimwalker polycounter lvl 15
    In similar manner you can separate sleeves from torso to solve shoulder parts. Those pieces would be separate on UVs and vertex normals too, so visually it doesn't even matter if it's one object or two.
    If character is supposed to speak then it would probably be easier to model him with slightly open mouth.
    Or you can simply pump more geometry into lowpoly to closer match highpoly.
  • gnoop
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    gnoop polycounter
    I find this separating and piece re-naming  tedious and annoying . In many cases you have to  keep  UV on hi res. Especially when you start from low res and detail it.   Sometimes  UV on  hi res is necessary  just to do small details there.     Then it's just baking object space normal map and  converting it into tangent space in Designer  or just one more re-bake in your render.   No ray miss errors whatsoever since it surface bake, not  mesh to mesh .     Works perfectly on CAD curve style models for example.  
    Tiny floating geo on hi res   could  just use its UV  projected from main surface  and bakes straight into that object space image  perfectly well  too.

    But to be honest I never did it for such a complex model .    Just another option that might be helpful.   
  • 0_sum_0
    dimwalker said:
    In similar manner you can separate sleeves from torso to solve shoulder parts. Those pieces would be separate on UVs and vertex normals too, so visually it doesn't even matter if it's one object or two.
    If character is supposed to speak then it would probably be easier to model him with slightly open mouth.
    Or you can simply pump more geometry into lowpoly to closer match highpoly.
    @dimwalker thanks for the reply
    And do I separate the highpoly in corresponding places?
    Regarding mouth area.I probably seen no one (various tutorials) sculpting a realistic character with the mouth even sligttly open, yet they show great result with no baking errors. Also, all the head sculpts on Artstation - lips are pressed to each other. So maybe they use morphs or smth. And often times  the polycount isn`t that big. 
  • 0_sum_0
    @gnoop Hm, interesting. But it seems to me that the approach you mentioned cannot be applied very often. For example the robe has some sort of attachment which you need to stitch with the robe on low poly stage. Then you cannot use the method you mentioned, right?
  • gnoop
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    gnoop polycounter
    0_sum_0.    yeah, sometimes the method doesn't work and it requires certain thinking ahead.  Some attached details could be  baked in  just fine like the buttons  if you have them as floating geo without the back side , some clothes details too.      Projecting UVs  doesn't work well over seams   etc.          Also depends on a  baking renderer.   Those having special "baking" camera  do it better usually. 
  • dimwalker
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    dimwalker polycounter lvl 15
    0_sum_0 said:
    dimwalker said:
    In similar manner you can separate sleeves from torso to solve shoulder parts. Those pieces would be separate on UVs and vertex normals too, so visually it doesn't even matter if it's one object or two.
    If character is supposed to speak then it would probably be easier to model him with slightly open mouth.
    Or you can simply pump more geometry into lowpoly to closer match highpoly.
    @dimwalker thanks for the reply
    And do I separate the highpoly in corresponding places?
    Regarding mouth area.I probably seen no one (various tutorials) sculpting a realistic character with the mouth even sligttly open, yet they show great result with no baking errors. Also, all the head sculpts on Artstation - lips are pressed to each other. So maybe they use morphs or smth. And often times  the polycount isn`t that big. 
    Yes, as Benjammin suggested. Both low and high would have same parts separated

    HD.fbx
    ---torso_high
    ---sleeve_high

    LD.fbx
    ---torso_low
    ---sleeve_low

    As for mouth, same here. I see everyone working with closed mouth, but when I tried to do it like that it was a pain all the way through. Doesn't bake right, harder to skin, even just dragging vertices around is more work, because I can't see inside of the mouth.
    So either there is a neat technique that I don't know or other guys have their mouths open while camera is off.
  • 0_sum_0
    @dimwalker @Benjammin thank you guys
    I've run some tests. Spliting hp and lp into pieces works just fine - clean bake, no seams. 
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