Search Unity

Construct new, simpler mesh by "tracing" complex collection of meshes?

Discussion in 'World Building' started by JoeStrout, Sep 20, 2018.

  1. JoeStrout

    JoeStrout

    Joined:
    Jan 14, 2011
    Posts:
    9,859
    I have a level that was constructed originally by overlapping a bunch of high-res rock pieces. We want to reduce both the poly count and the overdraw, by replacing a whole collection of these with a single, lower-poly mesh.

    I'm picturing a tool where we can click on the existing mesh to create vertices for a new mesh. Click click click, make a triangle; click again, make another triangle connected to the first, and so on to create a whole triangle strip, and eventually a nice low-poly mesh that approximates the original collection of meshes.

    Is this possible with ProBuilder? Or is there some other tool for the job?
     
    JoeStrout, Sep 20, 2018
    #1

  2. gabrielw_unity

    gabrielw_unity

    Unity Technologies

    Joined:
    Feb 19, 2018
    Posts:
    963
    Hmm, 2 solutions I think of first:

    1. ProBuilderize the whole thing, then manually delete the hidden faces, maybe even do some custom cuts/etc to extra-optimize things
    2. Pull the whole thing into 3DS Max/Blender/etc, and do a series of Boolean operations to precisely-and-automagically remove all extra surfaces.

    The 1st option will result in an easy-to-tweak mesh, ie if you decide to move some parts around later, but will be plenty of manual labor. The 2nd option will be more exact, and look just fine, but under the surface you'll have really messy, high-poly mess of geometry.
     
    gabrielw_unity, Sep 20, 2018
    #2

  3. JoeStrout

    JoeStrout

    Joined:
    Jan 14, 2011
    Posts:
    9,859
    Hmm. Neither of those is too appealing — I'd sooner make my own tool that works as I imagined above.

    @MediaGiant? Is this something Mesh Builder could do?
     
    JoeStrout, Sep 20, 2018
    #3

  4. neoshaman

    neoshaman

    Joined:
    Feb 11, 2011
    Posts:
    6,493
    the correct term is "retopology", if that help you find more alternatives, solution, tutorials, etc ...
     
    neoshaman, Sep 21, 2018
    #4

  5. MediaGiant

    MediaGiant

    Joined:
    Sep 14, 2013
    Posts:
    304
    With my tools all I could suggest is something similar to what Gabriel was talking about. Use Prefab Maker to create one mesh and then trim away the hidden triangles using Mesh Cutter. The only downside might be that Prefab Maker cannot handle tiled textures (UVs outside of 0 to 1) so that does limit the types of models it is suitable for.
     
    MediaGiant, Sep 21, 2018
    #5

  6. JoeStrout

    JoeStrout

    Joined:
    Jan 14, 2011
    Posts:
    9,859
    I should have mentioned, UVs are not relevant here (I'm using a triplanar shader). So that simplifies the problem a bit.

    But I really don't think cutting away triangles is what I want. I can picture what I need; pity there's no good tool to do it.
     
    JoeStrout, Sep 21, 2018
    #6