They’re great. In Blender you can do some awesome things with curves.
Today I’m going to show you one of the less awesome but still pretty cool things you can do with curves.
Well, I’ll take it as far as having one pleated ribbon in a circular shape. You can probably do the rest.
Before we begin, here’s a look at what we’re going to make.
The overall shape is made up of three curves.
The first curve describes the shape/profile of the pleat.
The second one describes the shape of the ribbon.
The third and final curve determines the shape the ribbon is formed into, in this case a circle, but you could use other curves for things like frilly cuffs or collars on shirts or… well, there’s probably other things you could use this for.
Step 1. Defining the pleat profile.
Start by removing the default cube (don’t we always).
Next hit shift-a to add, then select curve, then path.
Why a path? I find them easier to use when I’m messing around with s-bends and suchlike as it makes sense for me to think about how they might look if they were 3D subdivision surfaces. You could use a Bezier or NURBS curve I suppose, but make sure you’re happy with how to manipulate them, because I won’t be detailing that here. There’s also the added benefit of the points on the path starting out straight, which they don’t with the other two. (For a great tutorial using Bezier curves, check out Dani Epstien’s site here )
It makes sense to name your curve at this point. I called mine “pleat”.
Tab into edit mode and jump to the Front (numpad-1) Ortho (numpad-5) view.
So now we want to make an S shape (ish) but we also want it to loop nicely so we have to make sure that the first and last points on the path are at the same z axis location.
Grab the points on the path as shown and rotate the pair of them around their centre (r) on the y axis (y) by, let’s say 90 degrees for now (90)
It’s becoming apparent that we don’t have enough points on the path to make the shape we want so go ahead and select them all (a, a) open the specials menu (w) and hit subivide (s)
With the outer two new points selected as shown, scale (s) them up a bit on the z axis (z)
Now to pretty much finish this shape off, select all but the outer two points (bearing in mind that there are now some extra ones in the middle due to the subdivide) and rotate (r) around the y axis (y) until it looks as shown.
This is probably an excellent time to save your work.
Step 2. Defining the ribbon width.
Tab out of edit mode and add (shift a) another path (curve menu, path).
We’re going to use this as the extrusion object for the first curve.
With your new path selected, set it’s name (I called mine “ribbon”, this is totally optional but comes in handy at times).
Then pop into top view (numpad-7) so we can rotate it the way we want it.
We want to rotate it (r) on the z axis (z) by 90 degrees (90) (r, z, 90, enter).
Righto, with that all set up, we can test that it works by reselecting the “pleat” curve, popping into the curve properties panel and setting the “Bevel Object” link to the “ribbon” object, as shown.
What you end up with is a lovely s-bendy ribbon shape. That’s sort of what we wanted, but theres lots more to do before we can get there. One thing to note is (as shown in the following picture), the density of the mesh is probably already too high for what we want to make (we’ll probably subdivide later anyhow). This is controlled by the “U” count of each of the curves. In each curves’ curve properties panel, set the “Preview U:” value down to something like 5 for the “pleat” curve and 1 for the “ribbon” curve for now.
Another good time to save perhaps…
Step 3. Extending the pleat curve.
The next thing to do is to make the pleat curve longer. I don’t mean stretch it, I mean repeat it. Logically speaking, you want as many repeats of the pleat curve as you want pleats in the finished model, but I bet you don’t know how many that is right now do you? 😉
FIrst things first, some of the stuff we may end up doing, we don’t want to do with the “Bevel Object” link set, so click the little “x” at the right hand side of the “Bevel Object” box on the curve properties panel for the “pleat” curve.
Next, hop over to the modifier panel and add an array modifier as shown.
We still don’t know how many we’re going to need but it doesn’t matter right now, it’s enough that we have the modifier in place for the moment.
Add a curve modifier as shown in the next picture.
We don’t have a curve to bend it round yet though so add (shift-a) a new curve->circle and set its name to “circle” (again, optional).
By default, the new circle will have a radius of 1 Blender Unit, which is too small for the ribbon we’re building, so scale (s) the circle on all axes by a factor of 3 (3)
Reselect the “pleat” curve and set the “Object:” link in the Curve modifier to “circle”. It should now be making its way round part of the circle as shown below.
Now increase the “Count” value of the Array modifier until it goes all the way around. Mine took a count of 5 before it was overlapping a little as shown.
This bit is slightly tricky, but it’s easy enough if you hold down shift while doing it. Reselect the “circle” curve and scale (s) on all axes until the “pleat” curve looks like it fits nicely, as shown below.
Now that we have our “pleat” going round the circle, let’s put the depth back in. Reselect the “pleat” curve and go to the curve properties panel and set the “Bevel Object” link to “ribbon” again. (Consider hopping into solid view mode (z) to get a better look at that mess!)
Huge, isn’t it.
Not to worry. With the “pleat” curve (which is now a surface) selected scale (s) on all axes to about 0.5 (0.5) (s, 0.5) and crank up the number of repeats on the array modifier, then scale the circle as before to make it fit if you need to (I didn’t because I’d used 0.5 as my scale so all i had to do was double the number of array repeats).
Looking good! Just a couple more things to tidy it up a bit. So save your work and then go set the “Merge” checkbox in the array modifier to on so it
merges one repeat to the next.
There’s no point turning “First Last” on because as far as the Array modifier is concerned, the last repeat goes nowhere near the first one, despite what’s on the screen.
This is because the Array modifier is executed first, then the Curve modifier, but trust me, you don’t want to try swapping those around.
Well, maybe you do. Try it. It won’t be a rosette, but you might like it for something else I guess. If you want to see what it is that the array modifier sees just after executing (to understand why First Last won’t work) just hop into edit mode with the “pleat” curve selected and you’ll see (provided you haven’t fiddled around with the modifier visibility settings that is).
The trouble with what I’ve just been talking about is that it does seem to mean that unless you apply both modifiers, there’s no way to get Blender to automatically close the loop so regardless of how “close” to fitting the curve it may look, there will always be a logical break between one end of the ribbon and the other.
I’ve chosen to live with that for now, and settled with the fact that eventually, when I have the model how I want it, I’ll just
apply the modifiers and close the gap by hand (well, with “Bridge Edge Loops” – woohoo!).
The other thing you might want to add is a SubSurface modifier, a Solidify modifier, an Edge Split modifier (if you’ve subsurfed) or all of these.
If you *do* add a subsurf, go and select your “ribbon” curve and crank the “U” count up a notch or two or the First-Last problem will be *really* obvious.
Once you’ve done that, slap a nice material on it and you’re away.
(Niceness of material is not guaranteed)
To make it easy to alter, keep the modifiers un-applied so you can change the size, and don’t convert it to a mesh until the last second, keep it as curves, then you can alter the profile of the pleat and stuff like that. The only thing to be careful of is if you move one of this little cluster of objects, you want to move them all or you’ll get some whacky (but useful in some cases) results. You could parent each of them to an empty perhaps which you would then use for position, rotation and scale, which would be super handy if you were trying to put loads of them on things that had won things I guess.
Disclaimer: In the image at the beginning, I went as far as adding a lattice and a lattice modifier to “squish” the middle bit in. If you want to know how to do that, leave a comment and I’ll tack that bit on the end of this.