Curved Arches tutorial
polycounter
Hey guys! A few of you mentioned that you wanted a tutorial on how to make arches (or other geometry) curve around a cylinder.
Well, this is my first tutorial, and so if it ends up being confusing let me know and I can rewrite it. I took too many pictures, but I'm more of a visual learner.
Here goes.
Let me start off by stressing the importance of the grid. Any sort of modular assets (even curved or radial) MUST be confined to the grid or you will encounter frustrating complications while modeling and using your assets. The grid is designed to keep things clean and simple.
In fact, I use it so much, I gave the grid options it's own hotkey: ctrl+alt+g
You'll end up using this a lot, as you'll be changing the size of the grid often. Keep it to 5, 10, 20, 40, and so on.
We'll start off by making an arch. This is just one way of doing it, but you are free to make the arch in whatever way you feel. I have found that this works well with more complex molding.
And so we start with a box. This will become our archivolt (decorative band of arch) in a moment.
Make whatever shape you want, but be certain that the top and bottom of this shape are filled, flat, and have only 1 face. This will likely be an n-gon.
Copy it, move it a number of units over, rotate it and combine both shapes. Remember that the center of these shapes will end up getting cut in half, so have them 4, 8, or 16 units away center-to-center. (probably have it wrong in this image, please don't count it).
Select the top faces and go to Edit Mesh > Bridge (options) near the top.
Be sure to have smooth path+curve selected and enough divisions to give you something to work with. I haven't figured out just how it works, but putting one more division than what you want seems to keep it even (for example, I put in 17, one more than the usual 16).
This will give you something ugly like this:
But we'll fix that, by referencing from a cylinder. Match the size as close as you can. The radius will likely be 1 unit bigger than the typical 4 or 8 (like 5 or 9 or something).
go into an ortho view, and select the curve you see in the arch. You may need to right-click and select control vertex
Just mess with the top 2. Drag it up, and scale it sideways until it gets as close as you can make it.
Much better
Here's why we had you move your two initial shapes away from eachother center-to-center. We'll be cutting off the ends with booleans. MAKE SURE EVERYTHING IS SNAPPING TO THE GRID. Or I'll slap you. Srysly.
Merge any stray verts
But that's just an example of how to make a simple arch. I know you can make something more elegant and beautiful than that. So we won't be working with that bulky piece of garbage. This is much better.
Well, this is my first tutorial, and so if it ends up being confusing let me know and I can rewrite it. I took too many pictures, but I'm more of a visual learner.
Here goes.
Let me start off by stressing the importance of the grid. Any sort of modular assets (even curved or radial) MUST be confined to the grid or you will encounter frustrating complications while modeling and using your assets. The grid is designed to keep things clean and simple.
In fact, I use it so much, I gave the grid options it's own hotkey: ctrl+alt+g
You'll end up using this a lot, as you'll be changing the size of the grid often. Keep it to 5, 10, 20, 40, and so on.
We'll start off by making an arch. This is just one way of doing it, but you are free to make the arch in whatever way you feel. I have found that this works well with more complex molding.
And so we start with a box. This will become our archivolt (decorative band of arch) in a moment.
Make whatever shape you want, but be certain that the top and bottom of this shape are filled, flat, and have only 1 face. This will likely be an n-gon.
Copy it, move it a number of units over, rotate it and combine both shapes. Remember that the center of these shapes will end up getting cut in half, so have them 4, 8, or 16 units away center-to-center. (probably have it wrong in this image, please don't count it).
Select the top faces and go to Edit Mesh > Bridge (options) near the top.
Be sure to have smooth path+curve selected and enough divisions to give you something to work with. I haven't figured out just how it works, but putting one more division than what you want seems to keep it even (for example, I put in 17, one more than the usual 16).
This will give you something ugly like this:
But we'll fix that, by referencing from a cylinder. Match the size as close as you can. The radius will likely be 1 unit bigger than the typical 4 or 8 (like 5 or 9 or something).
go into an ortho view, and select the curve you see in the arch. You may need to right-click and select control vertex
Just mess with the top 2. Drag it up, and scale it sideways until it gets as close as you can make it.
Much better
Here's why we had you move your two initial shapes away from eachother center-to-center. We'll be cutting off the ends with booleans. MAKE SURE EVERYTHING IS SNAPPING TO THE GRID. Or I'll slap you. Srysly.
Merge any stray verts
But that's just an example of how to make a simple arch. I know you can make something more elegant and beautiful than that. So we won't be working with that bulky piece of garbage. This is much better.
Replies
Now we'll make our radial reference grid. Start with a cylinder that has 16 segments, and a radius of 4, or 8, or if you're feeling really ambitious, 16 or higher. Snap it to the center of your scene.
And another one. But this time, 128 segments around, and 16 segments on the caps.
Move your arch into position. It'll need to be rotate along Y exactly 11.25 degrees.
FREEZE TRANSFORMATIONS. Found in the Modify dropdown
We're going to create a lattice that will be our primary deformer to bend the arch around this curve.
In the animation menu, go to Create Deformers > Lattice (options)
No need for local mode, make it 9x2x2.
This makes it 8x1x1 segments.
Start snapping each lattice vertex from the top ortho to your radial grid that you made. The large 16 sided cylinder defines where the edges of your arch should go. The large 128 sided grid guide the verts in between.
Be careful. When snapping to vertexes, you must be sure to use the transform tool arrows. Otherwise, you will flatten your arch. Check in perspective view often to make sure you didn't screw it up.
One more thing. Even though it's curved, it's not quite matching up with the actual curvature of the cylinder. You'll need to move the lattice verts in the middle outward so the geometry of the arch matches up. Helps to do this in Object Transform mode in your tools options.
Let's take a look. OMG it's too tall!
Easy fix. Be sure to be using grid snapping throughout all this.
So you have one arch. Lets make an array of arches. Make sure you freeze the transformations of your first arch if you haven't already. Take note of these angles. You may use every one, or every other one, depending on the size of your arches.
You got this one. I don't have to tell you how to do everything.
Use a calculator if you need to. Keep adding 11.25
Then just duplicate your quadrant of arches, freeze transformations, and rotate again until you have a full circle.
There you have it! I forgot to note that you can delete the faces on the sides of the arches, so you can merge them seamlessly. If you did this right, you will be able to merge all the verts of each arch perfectly into one solid mesh.
POST AND QUESTIONS YOU MAY HAVE HERE, and I will try to answer them
edit: haha, I've been editing the crap out of this post for some reason. But you replied to it so I guess I'm going to leave the last part there.
Those last images are renders from a school project I did last year. That project is where I developed this method.
tristamus: no problem, man!
Anyhow, cool tut (:
I'm a max user and I normally I create a path/spline for the arch, create a shape path and sweep it over the arch. You can adjust either the shape and the default UV's that are generated work for most things really well.
You can also create a straight piece of geometry and path deform (WSM) it over the arch path/spline, I suggest doing it to an instance that way you can work on the straight piece while the curved one is updated as you work.
If that doesn't make sense I can kick up a few visual examples.
EDIT:
sltrOlsson: I'm not familiar with the blender modifier, but I use the lattice because you can precisely snap the verts to the grid or other verts. This is what gave the arch it's precision.
set up your curves for the arch and the profile:
Go to Surfaces>Extrude>options with the curves selected (profile first):
If the tube/arch is inside out, you can rotate the profile curve or go to Curves>Reverse Curve Direction.
A node called nurbsTessellate has the value for the number of divisions (polygon count):
modifying either curve afterwards will affect the shape/profile of the arch:
I like the Tesselation Method: General as well where you get to decide U and V spans.
Just make two point spline, then refine, add another point somwhere in middle of spline, make that point Bezier, tweak, you can also make it Bezier Corner. Next enable rendering in Viewport. Voila, we have arch of any shape we can possibly imagine. From moorish horse arch to gothic
Also dont forget about symmetry, as you get only half of arch. Then.. Then you are welcome to weak, add more details or just export to zbrush/mudbox.
First I make my base shape, in this case I just beveled a cube for a brick. I snap the pivot of the cube to one of the corners, making sure that it's in one of the outermost verticles.
I duplicate the cube and snap the copy to the matching opposite corner.
I click shift+D to duplicate with transform which will make a new duplicate and move it the same distance as the previous. I keep clicking shift+D many times to make a nice row of evenly spaced bricks.
I grouped and rotated the cubes 90 degrees so they stand straight up. Of course I could have duplicated them straight up from the start but... I forgot.
I make a bend deformer.
I input a value of 1.570796 which is half the value of pi. If you wanted to make a perfect circle you would input 3.141592, if you wanted a quarter of a circle you'd input pi/4 which is 0.785398, and so on. Keep in mind that while it displays 1.571 you should type in about six decimals as maya will actually note the difference. This can cause issues if you want to perfectly line up verticles for merging. Especially if you want to make a perfect circle.
And here's my arch.
Of course you don't need to use bricks. You can make elaborate tileable segments and merge them afterwards. Or if you want to make it look more interesting you can rotate, offset and add details to the bricks before you apply the bend deformer.
Deformers are incredibly useful modeling tools, they can save you a ton of time of used properly.
???
Create one arch, copy it a bunch of times in a straight line, instance it (so you can work on unbent arches later)
At this point you can do it two ways:
A) Apply the bend modifier to one of the instances of arches (be mindful of your pivot).
- You can then scale and edit the straight arches (in sub object mode like element) to close any gaps and make the arches fit more or less perfectly.
OR
Note: Create Shape + Sweep is VERY handy for all kinds of things like doing trim around windows & doors, creating gutters, pipes and wires, all kinds of stuff.
- Apply path deform(WSM) to the instance of arches and target the path you just made.
- Adjust the "Stretch" value to close the gap and use "percent along path" to slide the arches around the cylinder.
- You can also edit the geometry in sub-object mode to push it out away, or scale it in just by sliding it forward or back, siding them side to side will also slide them around the cylinder like "percent along path". It just depends on which option you're closest too.
For me, B gives me more flexibility and control but takes a little longer, A is quick and if its a quick and easy job where I know bend will work fine I'll do it.
Create an object and set the pivot to the desired location
Shift+d to create a duplicate object
Transform the object any way you like, but make sure you do not unselect
Shift+d again to duplicate with previous transform
Keep pressing Shift+d!
If you use this method all you have to do is rotate your arch 11.25 degrees and Maya will fill in the rest
Hope this helps
I will use the following shape or shapes similar for my arches (top view):
First Method is the easiest but doesn't give you specific control over the arch after you make it. Go into edit mode (tab) and use the spin function:
and as far as arraying along a curve i'll just post my tutorial that covers a few of the others as well:
(4:48 for array+curve specific)
[ame]
I'll work on getting these included into the Wiki after the Brawl winds down. If you could hold off on removing any images or videos until I get a chance to download and archive them that would be awesome!
Thanks again guys for a great thread.
Part 1
Part2
Final render
(Of course, I will remove the pics if it's a problem)
Sticking it anyway .... thanks a lot