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The "curve"

zombie420
polycounter lvl 10
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zombie420 polycounter lvl 10
One thing that always baffles me is the smooth curve that so many artists apply to their work. It's aesthetically pleasing but I never understand how it's applied. It's hard to explain but I'll try:

I want to make an outdoor scene with an old asphalt road that smoothly curves away in the distance, most likely applied with something like UDK's terrain editor and terrain materials. My problem is that when making a texture, it's always in a straight line. So how do I get that smooth bend that's so common in so many scenes? Multiple textures? non-directional texture and multiple yellow-line decals?

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  • respawnrt
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    respawnrt polycounter lvl 8
    Make the road in line form, unwrap it and bend it after that :)
  • zombie420
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    zombie420 polycounter lvl 10
    By "bend it" do you mean bend a mesh? Because I'm not hoping to use any meshes for this
  • Kurt Russell Fan Club
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    Kurt Russell Fan Club polycounter lvl 9
    Could you show a picture of what you're after?
  • passerby
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    passerby polycounter lvl 12
    so why would you avoid uses meshes, when doing this is as simple as making a straight road(and texturing it as a straight road) and tossing on maya's bend deformer, or max's bend modifer?
  • Mark Dygert
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    What software are you using? If this was max you could in theory do it all with splines fairly easily, with Maya its a possible but to do with splines but more trouble than its worth.

    Depending on the curves of the road here is what I would do in max.
    1. Create a blocking model for a straight stretch of road (evenly sub-divided modular chunk that gets copied a bunch of times).
    2. Create a path spline, by drawing a spline on the surface of the terrain.
    3. PathDeform(WSM) an instance of the blocking model over the path spline
    4. Go back to the original straight blocking model and adjust the length to make sure it covers.
    5. Finalize the mesh model.
    6. Adjust the rotation of segments with soft select turned on as needed.
    7. Done.
    OR
    1. Create a road
    2. Use Geometry projection http://www.scriptspot.com/3ds-max/scripts/geometry-projection?ref=nf
    3. Done
    If you want to do zero mesh interactions it actually gets a lot harder...
  • zombie420
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    zombie420 polycounter lvl 10
    Sorry I was so vague. This is a crude example of what I'm trying to describe:
    dQ7OQ.jpg

    I feel like if I make a mesh, I'll have to make it modular. If I make it modular, I'll be constantly adjusting the terrain to cooperate with the mesh pieces. Also, wouldn't I have to do some working with the light maps to not give me seams where the flat geometry meets? I could be wrong though, never tackled something like this. But I feel like if I could just bend the terrain material, it'd make my life a lot easier.
  • r4ptur3
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    r4ptur3 polycounter lvl 10
    Using one giant piece of mesh is acceptable but expensive. You might also run into culling issues (it will pop in and out of existence) based off the pivot location. Try exporting your terrain as an obj or fbx and tracing it in Maya or Max. You can also split the road into modular pieces and lay them out based off the same mesh. It all depends how you want to handle it :)
  • Kurt Russell Fan Club
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    Kurt Russell Fan Club polycounter lvl 9
    I feel like if I make a mesh, I'll have to make it modular.

    I think this is your problem. You don't need to do that. You can create your terrain however you want and then model the road to match that terrain.

    You can break up your road into pieces but they don't have to be modular pieces. What I mean by that is that usually modular road sections (say for a city) will consist of a straight section, some curved sections at certain angles (45,90), some t-junctions and intersections, and the like. You don't need to do that -- the reason you'd break your road mesh up is primarily to stop from having one massive mesh that's always drawn - reusing the parts is important if you can, but (depending on the vert count) not necessary.

    But check out the features of whatever engine you'd be working with. A lot of engines have their own road system to go with a terrain system.

    Crysis: [ame="http://www.youtube.com/watch?v=m5kYD1jTSoc"]Crysis Sandbox Editor Tutorial 1, Roads - YouTube[/ame]
    Far Cry 3: [ame="http://www.youtube.com/watch?v=GjCQ-i80QGk"]Farcry 3 Map editor tutorial #04 Paths and roads - YouTube[/ame]

    The road systems will run better than a mesh solution, with engine-handled lodding and visibility. Unless you want something really specific (producing a look you can't get in the engine) then you should use them.
  • zombie420
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    zombie420 polycounter lvl 10
    Kurt Russel, thanks a lot. That is literally EXACTLY what I was hoping for/ asking about. I've been needing a reason to begin a CryEngine project and this may be it, but we don't know if UDK has a similar feature by chance?
  • Kurt Russell Fan Club
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    Kurt Russell Fan Club polycounter lvl 9
    No worries :)

    The closest in UDK that I know about is the spline loft actor. It's less "paint and forget" than normal roads, but it lets you use modular mesh pieces and to build your road (or whatever - it doesn't have to be roads) and then deform the shape using splines. If you want to see it in action, open up the FoliageMap demo and search for a SplineLoftActor.
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