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Creating a modular bending tunnel for UT

polycounter lvl 12
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alexk polycounter lvl 12
I'm having a hard time figuring out how to create modular chunks for a tunnel with a bend, while keeping the modular chunks lining up properly to a grid. That way, I can easily assemble it within UT3.

I'm stuck at the bend, where I take my straight piece (a half cylinder, which is aligned to the grid) and apply a bend modifier with a 90 degree setting. The problem is the end of the bend does not land on the grid, and so in UT3, I can't snap my straight chunk to it. How do I get my bend chunk to fit nicely on a grid? I'm open to any other methods of doing this as well, so feel free to suggest anything.


tunnelprob.jpg

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  • Kawe
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    Kawe polycounter lvl 8
    Im guessing it's cause you have the pivots differently? If you put it in the corner you should be able to line them up I believe.
  • Ben Apuna
    You could take a cross section of your tunnel and extrude it along a spline. Just make sure the spline and the cross section align to the grid. For a perfect 90 degree turn like that just take a circle spline primitive turn it into an editable spline and delete 3 of the segments.
  • Mark Dygert
    I'd do it with a few rotated symmetry modifiers. As long as the pivot is placed on the inner corner of the straight piece, its going to line up perfect. Right now your inner corner is traveling off the grid which means the next straight piece you align is going to be off the grid also, that's kind of messy.

    3dsmaxCornerPiece.jpg

    Or for a more rounded corner you can push the walls in a bit.
    3dsmaxCornerPiece00.jpg
    But still keeping the pivot points on the grid. I think the key here, is stick to the grid.
  • Peris
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    Peris polycounter lvl 17
    heres how i usually do this:
    place a copy of the straight part at thesame location on the grid as you did in unreal, then align your curve to that by moving the bend modifier gizmo until it aligns. Then snap the vertexes to the straight copy so there will be no small gaps. voila!
  • Ryno
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    Ryno polycounter lvl 18
    In Maya or Max, I'd just instance the tunnel, rotate it, snap it to grid in the correct location, then move the verts of the original to snap up to the back end of the instance.
  • alexk
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    alexk polycounter lvl 12
    thanks guys. I used Peris suggestion and it worked out. Vig, if you have some time, can you explain more about your method? I couldn't seem to replicate it on my end, I don't fully understand how you used symmetry to create the bend. if it's not too much trouble, of course :)
  • Mark Dygert
    So here's whatca do.

    You can do this with with highly complex objects also, its pretty handy at transforming straight hallways into bends.
    The key is to use the grid to align the pieces not the pieces themselves. Build your pieces to the grid, snapping verts and edges as you go so everything is water tight, but separate objects.
    Engines use a grid also so it makes perfect sense to make sure your grids match before you start building.


    - Take your straight piece however detailed it might be, move the pivot to the upper right corner, I snap it to the grid.
    - Add symmetry so its mirrored and looks like a long hallway two units long.
    - Copy the symmetry modifier.
    - Turn on angle snap.
    - Paste symmetry and highlight it so its yellow.
    - Rotate the symmetry gizmo 15 degrees.
    - Copy symmetry and paste it, highlight it and rotate it 45 degrees this time, you should now have a 90 degree bend.
    - You'll notice you have two flat loops, you can pull these out or remove them, I normally pull them out to round the corner a bit.
    - Delete the extra straight pieces and you've got your corner!

    Note you can do the same thing to make a 90 degree corner, just use one symmetry modifier and bend it 90.

    Also you can script some of this so its automated, but I've not gotten around to doing any of that, its really not going to save that much time...
  • Saidin311
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    Saidin311 polycounter lvl 11
    Hey vig, I got a question. If you wanted to make a corner piece like your second one. You said you pushed it in a bit.

    But now it all of a sudden doesn't fit on the grid. Sure you're pivot point is still there but it's gonna be a lot more time consuming if you still have other sections of the wall to make. To have to line everything up in some sort of half-grid doesn't make sense to me. What would you do to solve this kinda thing?

    At the heart of it, If I want to make a corner section, I'm always blowing my brain up because I can't figure out how to get that nice inside rounded corner without making the entire corner section some huge-ass piece that bends around the actual points on the grid.
  • Mark Dygert
    The wall would snap to the sub grid. Say 75 not 100. Pivots stay on the major grid lines at 100.

    If you want to keep your straight wall sections snapped to the major grid lines and you want a rounded corner, you extend your corner to include a straight section of the hallway in both directions. Then move the wall into 75 do your bend, and push the entrances back to 100 leaving the corner pushed in slightly.
    3dsmaxCornerPiece01.jpg3dsmaxCornerPiece02.jpg

    Suggestions:
    - "Active Grid Object" (create tab > Helpers > Grid) is just like the default grid, but this one can be moved and rotated, say 90 degrees so now you have a vertical grid to work with on your walls.

    - You can have as many custom grid objects as you want, BUT you can only have one grid active at a time. So to activate it, select the grid object, right click and toggle on "Active grid". To set it back to the home grid (horiz) do the same thing but set it to activate the HomeGrid.

    - Key bind ActiveGrid(context) Nothing selected it will activate the home grid. With a custom grid selected it activates that one grid.

    - Figure out your grid sooner rather then later.

    - Recenter the pivot point while you work on pieces.

    - Use symmetry to make sure the entrances match. You don't need to do symmetry on the entire section, you can detach just the ends.

    - Create pieces like support beams, pipes, wires ect that cover seams, they can hang half on/off the grid. That way you're not stuck micro managing verts.
  • Tumerboy
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    Tumerboy polycounter lvl 16
    Vig, why do you have to distort the corner? If your piece is extended by the length of 1 straight piece in both directions, then you have all of THAT space to play with. Your pivot stays in the same place, but you can do what ever you want to the geo between the end points.
  • Mark Dygert
    Mostly for line of sight blocking. This being a 90 degree corner blocks more then a relaxed rounded corner that cuts across the the huge open space. Its perfectly fine to do it that way, but its not going to fit inside of a 90 degree boxed hallway without some changes or a bigger buffer.

    You could do something like this instead, and not use a full unit on either side. It still keeps to the grid, and is probably closer to what Alex was originally looking for?
    3dsmaxCornerPiece03.jpg
    Position the bend pivot to the opposite corner and bend it 90 degrees.
    It won't be perfect but you can then set the objects pivot to the inner major grid line (the true corner), and run symmetry on the piece.
    Rotate the symmetry 45 and it should come out perfect (might need to flip it).

    You could probably do the same thing by just moving the symmetry pivot to the true corner, but there might be some clean up work on the outer edges.


    Personally for a 90 degree bend. I'd use the top most example I listed with a sharp inner corner and a smooth rounded outside bend. Most people give two craps less about rounded inner corners and never notice, especially on a 90 degree bend. You also have to keep in mind that the detail on the inner corner is going to be smashed quite a bit, and it often looks better if its cut at 90 instead of bent and smashed.

    Six of one half dozen of another, there are a bunch of different ways to do corners. As long as you do them in a way that keeps to the grid.
  • Tumerboy
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    Tumerboy polycounter lvl 16
    Here's a quick and dirty version. I mocked it up with planes just because it's faster, but you can do it with whatever shape geo you want.

    This is all on a 10' grid. So you'll notice the pieces on the right are 10x10'. The Red Boxes show where each piece's pivot point is. I like keeping my Corner piece's pivots in the center, so that I can rotate it in place and easily connect up to whatever is on any of the 4 sides.

    A) is the usual approach, where you have a curve on the outside, but a sharp corner inside.

    B) is double size, so it covers a 20x20' area, but lets you do a more gradual curve without a sharp corner.

    C) However, is still in a 10x10' grid, but since the pieces don't fill ALL of that space (the straights are actually 8x10') you have a little room to round out the inside corner on the corner piece.

    3406486157_1f74dfdd66_o.jpg
  • Peris
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    Peris polycounter lvl 17
    Vig wrote: »
    3dsmaxCornerPiece01.jpg3dsmaxCornerPiece02.jpg


    vig, i dont really agree with that way of doing it, i used to do that before aswell but you'll run into problems when you want to have 2 tunnels right next to each other on the grid, they'll be sharing a paper thin wall!
  • Mark Dygert
    Well if this was actually a tunnel, it would be shelled and detailed inward a few units and any tunnels running parallel would more then likely be offset a few units so their outer bounding areas don't even touch.

    But if you really had to snap two parallel paper thin tunnels to the same grid line you can get around the problem by sloping the walls toward the center point of the roof. So the only point they share is a tiny fraction down by the floor.
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