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Low poly from high poly workflow?

Discussion in 'Formats & External Tools' started by MrDude, Jun 22, 2011.

  1. MrDude

    MrDude

    Joined:
    Sep 21, 2006
    Posts:
    2,569
    Hi all.

    With pixologic now showing some love for Macs I am a bit more curious about something I've been wondering about for a while now.

    Okay... so... You create your low poly mesh and do your unwrapping and when you are done, you load your model into something like zBrush or Mudbox and subdivide like crazy and do your sculpting. Now you have your bump mapping and all is good with the world...

    Now, let's say you are NOT a low poly modeler and you only know zBrush. You are a master of your craft and can make awesome looking creature models using only 5 billion polygons! You are the man. Now you come into video games and want to make game content... As I understand it, zBrush only does high polygon. It does not do polygon reductions apart from if you start with low and subdivide then you can go back to the original version but that is as far as it goes...

    How useful is a tool like Mudbox or zBrush as a standalone choice for creating game content? Is it even possible for a workflow to exist that uses these as the sole development apps? I know Daz has a great poly reduction tool for their stuff and on thegamescreators.com they have a very decent poly reduction tool for Windows, but is there a way for Mac people to use Mudbox or zBrush as their sole development environment and then use some or other polycruncher to make the models game ready?
     
  2. Krobill

    Krobill

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    Nov 10, 2008
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    The main reason people stick to doing low poly stuff and then going high poly is : ease of unwrapping and animation. When it comes to the skinning process, you have to have your usual loops of vertices above and under every joints to make it simple and clean. It's unlikely a procedural polygon cruncher will be able to take that into account and you'll end up with a lot of manual work to correct all the 'irregularities'.
     
  3. larvantholos

    larvantholos

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    Oct 29, 2009
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    Alright, actually, Zbrush workflow lets you work from high to low as well. Because you are baking detail, all you need a mesh that resembles the overall shape if your main mesh, and there are a lot of ways to go about doing that, a few in zbrush itself for instance, it has re-topology tools, as well as you can make some solid starter meshes in zbrush itself, for going outside of zbrush, you have a few options, what a lot of people do is export a medium res mesh to make their low res mush from, in say maya or 3ds max or whatever your comfortable with. If you can't get your mesh low enough, while maintaining enough detail, you can also use zbrushes plug Decimination master which will dramaticly reduce the poly count while maintaining the meshes shape as closely as possible, this will let you take it out of zbrush and retopologize it to an optimized mesh for animation.

    It is possible to use zbrush alone, but your likely going to want to use some modeling program along with it to speed up any of your low poly workflow, as zbrush simply isn't designed to build fast efficient low res meshes.
     
  4. MrDude

    MrDude

    Joined:
    Sep 21, 2006
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    That was basically what I though. I was coaching someone recently about which modeling app to learn and I said that zBrush is a very popular tool and you can do quite a lot with it but for games, I would rather say learn something else and when you have some spare time, learnt that also...

    I was thinking what you just confirmed, but since I am no zBrush master I was afraid that I might be wrong in this.
    I was thinking: Build the high polygon model, export it to Maya, crunch it down, do the UV layout, take it back into zBrush and fall flat on your face because now you have two models with separate UV layouts... Obviously that can never work... so the better approach is to build it in high detail, texture it and be done with it and then crunch it down inside the same app... if possible.. that Decimination plugin seems like the thing I was thinking of... so the question remains... how well does this work.... Hmmmm...

    Either way, it seems starting high and going low is just plain simply a bad idea. Just as I thought.
    I was considering taking the time at some point to properly learn one of these tools and got to thinking: "I wonder if I would ultimately be able to replace Maya with one of these? Hmmm..". I assumed "No", but thought I'd ask, non the less.

    K, thanks :)
     
  5. LordMoggy

    LordMoggy

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    Aug 28, 2010
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    love your avatar! lol!
     
  6. Tudor_n

    Tudor_n

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    Dec 10, 2009
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    I've tried two basic workflows so far. Low to High and the other way around. Both have their downsides. Both need to use a sculpting app.

    High to low. When going from sculpting program (zbrush usually) to low-poly, it's simply easier to recreate the low poly mesh from scratch (using the high-poly as a guide) rather than Decimating and cleaning. Personally, I find this extremely annoying, especially when you're dealing with animated characters.

    Low to High is a wee bit easier imo. You create the low-poly in any poly modeling tool, drop an edit poly on top of it and process it for the sculpting program (chamfers, polygon density, etc). You then process it in the sculpting app (I prefer Mudbox with this workflow), delete the edit poly stack from the original and bake your normal maps using your sculpted mesh.
     
    Last edited: Jun 22, 2011
  7. larvantholos

    larvantholos

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    Well, there is one thing to consider, with Zbrush now, using its ShadowBox, you could feasable replace the low poly stage, just remeber you gotta create something low in EITHER way to get it into the game later on.
     
  8. Aaron_MyZ

    Aaron_MyZ

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    Apr 7, 2013
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    1
    hi can u help me between maya and zbrush
    1.i made base mesh in maya a human T model
    2.imported in z brush..worked on high poly ...painted textured..
    3.now in maya i unwraped low poly uv's
    4.now i am trying to apply low poly uv's to high poly model in zbrush and i done know how to go about it
     
    Last edited: Apr 7, 2013
  9. artzfx

    artzfx

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    Apr 28, 2008
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  10. larvantholos

    larvantholos

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    You can use uv master to import your low poly mesh uv's, however since you sculpted on it, those will now be distorted, if you just want uv's you can use uv master to generate them, you still should generate a low poly mesh first, from your high poly mesh you now sculpted, and uv that instead.
     
  11. kierenhovasapian

    kierenhovasapian

    Joined:
    Dec 23, 2014
    Posts:
    87
    I made this full workflow tutorial that would be a great help for this discussion.
     
    samana1407 likes this.