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getting straight unwrap from pips/cylinders

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Notes polycounter lvl 4
In the picture, the first unwrap is what im trying to get out of the unwrap...the first on all the edges are connected together nicely so I can texture with a nice flow from one poly to another...but this unwrap was automatically generated when I hit the unwrap uvw modifier, this was the only cylinder that was unwrapped like this by max...the rest weren't as desirable.
the 2nd unwrap is the one I keep getting from using various unwrap/mapping options...no matter which unwrap option I've used, I could not produce the same unwrap as the first model...help?

im using max 2012 btw...thanks again guys

6yh3jo.jpg

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  • Mark Dygert
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    I prefer to work with splines for this kind of thing. It's a great way to generate UV's, the high poly and the low poly all from one tiny little spline.

    Spline > Lathe > Generate Mapping Coords
    Lathe:
    LabLathe.gifLabLatheUV.jpg
    Create a profile spline (point, click, point, click, or use a spine drawing tool, there is one in Graphite Modeling as well as scripts (soulburn scripts is great)
    Then apply the lathe modifier, then you can refine and tweak the original profile spline and it changes the shape of the entire piece.

    Applying turbosmooth to the top of the stack is a great way to get a good preview, you can then go back down to the profile spline and work on one set of verts and it effects the entire piece. Need reenforcing edges? Click refine, click two points and you're done, no chamfer, no messing with caddies or cutting in loops, just drop in two points.

    You can also remove points easily which is a great way to create your low poly. I select all the verts, then choose which one are the most important to the silhouette and deselect them. Again no unwrapping because its a spline. I love this method.
    Oh but that doesn't do much for you now does it... well actually you can select a vertical edge and in edit poly click create shape and then add the lathe modifier. You probably want to center the objects pivot before creating the spline and applying lathe.
  • EarthQuake
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    "gridmapping" on cylinders that have varying widths can often result in very heavy distortion, I prefer to just clamp on one axis.

    some images from an older thread:
    uvtest3.jpg

    Like the middle layout above^

    from: http://www.polycount.com/forum/showthread.php?t=80947
    http://www.polycount.com/forum/showpost.php?p=1286315&postcount=55
  • Mark Dygert
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    Oh also, there is a newer option in 3dsmax 2012 called "Straighten Selection" which can be helpful also, it helps square off UV's again.

    Like EQ said the distortion on pieces is going to depend on difference in the shape and the way you unwrap it depends greatly on the material that is going to be applied. I'm not sure squared off UV's in your top example is the best way to go. If you're baking from a higher poly source then the distortion will be handled to a good degree by RTT.
  • EarthQuake
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    Even if distortion is handled by the bake, heavily skewed/stretched uvs are going to look bad if the texture has any noise/pattern to it. So unless its a totally smooth surface without any material detail, I would avoid heavy distortion.
  • r4ptur3
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    r4ptur3 polycounter lvl 10
    If you buy the pro version of headus3dLayout you can accomplish this by pressing R, I think. Stumbled across this awesome hotkey by mistake.
  • NoltaN
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    NoltaN polycounter lvl 15
    The way that I handle this problem in 3ds max is to use the WHITE align tools. The tools are hidden under the traditional align tools in the Quick Transform tab. To access them you must click and hold on the orange handled align tool and then select the white one.

    I hope this image explains the process. You can leave the UV's at step 2 for less distortion as Earthquake suggested.

    Also, I use hotkeys to ring and loop select the UV's faster. The whole process of pelt mapping, relaxing, then straightening takes about 15 seconds.

    UVstraighten.jpg
  • Mark Dygert
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    EarthQuake wrote: »
    Even if distortion is handled by the bake, heavily skewed/stretched uvs are going to look bad if the texture has any noise/pattern to it. So unless its a totally smooth surface without any material detail, I would avoid heavy distortion.
    It's not guaranteed to look bad. It would help even in your middle example where you clamp to one axis. I really think you need to play with it some more.

    You and I both know you can't get rid of distortion but you can minimize it to acceptable levels.

    Here is an example taken from the projection painter demo which illustrates the point pretty well and works off the same principle.
    DistortedUVs.jpg
    On the left:
    The diffuse map, with distortion. That distortion would be hard to mimic on your own. It would take a life time trying to get rid of the distortion so a non-distorted greenthooth looked as right as it does in the example on the right.

    On the right:
    This is how it looks applied to the model. Because the greentooth was distorted automatically it looks better than if you just applied a non distorted greentooth over the distorted UV's.

    It's the same reason why people don't try to paint waves into normal maps to round out cylinders. I'm not saying this is a cure all method that works for everything but it can help work around mild to moderate distortion.

    People need to pick the best method that works for them in that specific case. They get there by having a variety of methods in their arsenal.
  • Mark Dygert
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    NoltaN wrote: »
    Also, I use hotkeys to ring and loop select the UV's faster. The whole process of pelt mapping, relaxing, then straightening takes about 15 seconds.
    If you're on 3dsmax 2010 or lower you'll need to use one of several UV alignment scripts that where floating around before they included the feature into 3dsmax. James Haywood and Neil Blevins both have good UV align scripts.

    I wrote one for myself that works just like NoltaN described.
    http://dl.dropbox.com/u/2336353/UVFlatten.ms
    Run the script one from anywhere then you can assign it to a hotkey from the Customize UI menu, category: VigTools.
  • Notes
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    Notes polycounter lvl 4
    NoltaN wrote: »
    The way that I handle this problem in 3ds max is to use the WHITE align tools. The tools are hidden under the traditional align tools in the Quick Transform tab. To access them you must click and hold on the orange handled align tool and then select the white one.

    I hope this image explains the process. You can leave the UV's at step 2 for less distortion as Earthquake suggested.

    Also, I use hotkeys to ring and loop select the UV's faster. The whole process of pelt mapping, relaxing, then straightening takes about 15 seconds.

    UVstraighten.jpg

    THANKS ALOT!!!!! took a few mins for me to grasp what you did from the pic but im on a roll now :)

    thanks to the other replies as well...I will have to try out some of those suggestions when Im done with my hw...
  • EarthQuake
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    Mark: You missed the point of what I was saying, of course on a completely unrelated example(minor distortion on an organic object with even texal density) a little distortion is going to be just fine. Baking from a high is excellent in that it covers for minor distortion, I never suggested otherwise.

    However; if you're clamping all your edges on a model like the OP's, you could end up with 1:4 pixel stretching on the thinest areas, which is bad no matter how you look at it. I mean if you think stretching your uv layout 1:4 is a good method to work with ok... but I wouldn't agree with that.

    You're also ignoring technical concerns, its generally best to split your UVs and smoothing groups at 90 degree angles(even with a synced workflow there are advantages). So while you can't negate distortion completely, generally there are common sense methods we can use to limit distortion and work well with the technical aspects of art creation.
  • EarthQuake
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    Relevant example:

    uvtest5.jpg

    A: Virtually distortion free, will bake better/more friendly with smoothing groups(which means more compatible with various engines, compresses better, easier to generate detail map from etc), will look better if texture has any surface detail or pattern, slightly more annoying to paint on.

    B: Easier to paint on, reduced vertex count, no other benefits.

    Honestly, B isn't "guaranteed " to look worse, there are some extremely specific situations where you might not be able to tell the difference, but its sort of like saying "a dog pissing on your leg doesn't guarantee that you'll have a bad day".
  • gsokol
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    Usually if I need to straighten out cylinder stuff, especially complex,bendy type stuff (and I was dumb and didn't use a spline and generate uvs) I'll use pelt mapping to get what I want pretty quickly.

    Just pick the seam where you want the uvs to split, pelt map, relax it, then straighten edges. Usually gets you what you want pretty quick.
  • Mark Dygert
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    EarthQuake wrote: »
    Mark: You missed the point of what I was saying, of course on a completely unrelated example(minor distortion on an organic object with even texal density) a little distortion is going to be just fine. Baking from a high is excellent in that it covers for minor distortion, I never suggested otherwise.
    It works with non-organic hard surface models that have minor to moderate distortion also.
    EarthQuake wrote: »
    However; if you're clamping all your edges on a model like the OP's, you could end up with 1:4 pixel stretching on the thinest areas, which is bad no matter how you look at it. I mean if you think stretching your uv layout 1:4 is a good method to work with ok... but I wouldn't agree with that.
    That's probably going to happen with it clamped in one direction also... But I agree, I'm not sure either approach would work best, probably the "wrong" example from the OP is best, but that depends on a few things that aren't said and he wasn't asking which was best, he was asking how to get UVs that where clamped in both directions.

    Solutions seem to be:
    • Straighten Selection, max's one button solution to grid-ify messy UV's.
    • Rebuild the geometry quickly using edge selection and splines that generate mapping coords.
    • UV align the loops and possibly rings? (use scripts if on older versions)
    EarthQuake wrote: »
    You're also ignoring technical concerns, its generally best to split your UVs and smoothing groups at 90 degree angles(even with a synced workflow there are advantages). So while you can't negate distortion completely, generally there are common sense methods we can use to limit distortion and work well with the technical aspects of art creation.
    That's starting to split hairs. Generally speaking less UV seams, means less verts overall, better performance.

    In the case of the OP I don't think the number of verts matters that much, but if that decision gets made on many parts over the entire model or even multiple models, it can start to add up. Those are risk/rewards that need to be hammered out and adjusted, probably with in engine tests and the help of a graphics programer.
  • EarthQuake
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    In the case of the OP I don't think the number of verts matters that much, but if that decision gets made on many parts over the entire model or even multiple models, it can start to add up. Those are risk/rewards that need to be hammered out and adjusted, probably with in engine tests and the help of a graphics programer.

    Urghhhh don't remind me, the pain of getting quality bakes with a broken tangent basis while paying attention to real vert count. agfdgfdagfd....

    Anyway the rest of the shit I think we pretty much agree on but are arguing semantics.
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