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Help with High Poly

Hello, I've been creating models for a while now but I've never really learnt any High Poly techniques for Hard Surface modelling. With not having any work to do over the Winter period and the festivities not starting yet I wanted to try and teach my self.

So the problem is I'm creating a barrel (simple to start) and I created a clone with supporting edges and I applied the turbo smooth modifier, now as you can see on the left model which is the base with the normal map it's trying to create the roundness that the high poly created but it can't because of the more angular edges. I also created another clone with support edges running downwards down the barrel, these then made the normal map get rid of the smoothing group edges and show the edges. Although this did help with the horizontal sections.

help.jpg

if anyone can help and maybe point me in the direction of a nice High Poly tutorial to get me going. Thanks.

Replies

  • Eric Chadwick
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    About the chunky-curves normal map issue, I think the consensus is just add more polygons on your low-poly model to smooth it out some. But you'll never get rid of the problem completely. Some info here
    http://wiki.polycount.com/NormalMap#Solving_Wavy_Lines

    About subdivision surface modeling...
    http://wiki.polycount.com/SubdivisionSurfaceModeling
  • PredatorGSR
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    PredatorGSR polycounter lvl 14
    You can also do a workaround that fixes that issue, but the downside is it is harder to do, and you don't get super nice smoothing. Basically you have your high poly have the same number of curve points as the low.

    We had a big thread about this a while ago, if you read through it you should find the answers you are looking for.

    http://www.polycount.com/forum/showthread.php?t=72713&highlight=normal
  • Addieo
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    Thanks a lot for the help and the useful links!
  • EarthQuake
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    In this case, simply double the # of sides on the asset, remove all these really small bevels for the ridges etc, and you'll end up with a better result with much less tris. Sure you wont have those tiny little ridges, but they likely wouldn't be noticed ingame anyway.

    Quick test to show various methods.
    left to right:
    A. Most accurate to high, wonderful, but insane tricount, 32 sides + all details modeled
    B. Very accurate to high, except not enough sides. tricount quite high but has worst wavyness of all, 16 sides + all details modeled
    C. Boring silouhette, but least wavyness outside of A, very reasonable tricount, 32 sides + support loop on either end
    D. Boring silouhette, very little wavyness, very low tricount, simple 32 sided cylinder

    Also note, in the last shot, at a reasonable viewing distance there is little difference between any of the 4 methods.

    barrel01.jpg

    barrel02.jpg

    barrel03.jpg

    If the asset needs to be very high quality, seen up close, A. with some healthy LODs is the best method, if you're only going to see it at a medium distance, D is probably the best method, however ALL of these seem acceptable, the wavyness on B to me is well within acceptable margins from most angles.

    I should have included a simple 16 sided cylinder example too, oh well. Lower than 100 triangles isn't really worth discussing(and arguably lower than 500) as the drawcall for the mesh is going to be what hurts performance, not a prop of such little geometry.


    Rar with:
    Highpoly obj(un-subiveded)
    Lowpoly obj
    Maya 2008 bake scene
    normal map TGA

    http://dl.dropbox.com/u/499159/barrel.rar


    Now, general issues with your model:

    It looks like your highpoly's details are too sharp and fine, resulting in a poor bake, the bevels on your low are also too small, leaving not enough resolution to correctly represent them in your texture, and just giving a very wimpy feel to the asset. And you have some smoothing errors, or possibly normal map applied incorrectly(does the green channel need to be inverted?) as well?
  • Eric Chadwick
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    Another excellent EQ drop of luv. hahah. I think you meant green tho not blue.
  • EarthQuake
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  • Scruples
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    Scruples polycounter lvl 10
    I would like to take advantage of this thread and use it to get some thoughts on this, assuming the engine doesn't recompute vertex normals you could freeze the normals and add any geometry you need to deform the silhouette or add parallax....

    While in itself not useful it allows you to reuse the same normal map on the low-poly that you use on the high-poly.

    I am also wondering if it is actually any more optimized reducing the tricount 892>764 when the vertcount remains the same.

    barrels.jpg

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  • ZacD
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    ZacD ngon master
    vert counts is typically what matters in most engines, tris is just easier to visualize and reduce.
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