Growing curves, new feature request?

I know that this kind of request may sound useless or not interesting for most of other users here. I also know that the same thing is achievable in other ways…
Well, it’s simply about growing curves. There’s the taper obj. option, if I’m right there’s the shape keys way as well… why not simply have in 2.5 a growing option as well?

Each of the current methods, while they work good, are not fast.
Let me explain a little bit the issue.
In last days I’ve been on a job full of 3D growing splines. Thinking to control the growing via taper or shape keys is not that easy. With regret I’ve had skip Blender as 3D choice…
It’s true that you can achieve almost everything, is not the tool but the designer, et cetera, but what about when you’ve got tight deadlines? the idea to handle tapers to have curves growing is not that good…

I have my own reservations about the curve system, specifically how they animate.

Have you tried curve deforming geometry, and making a shape key of it growing straight out?

The Anti-Christ that is The Z-Twist

  	 		The Anti-Christ that is The Z-Twist 	

Didn’t they say somewhere that’s on the ToDo list for 2.5?

That’s what I meant by the shape keys way.
If I’m right the steps are:
1 - Create a curve
2 - Create a cylinder
3 - Add the curve modifier to the cylinder
4 - Create the shape keys - this needs more steps, since the cylinder needs to be subdivided along the z-axis to keep the mesh smoothed along the curve, then to have a nice growing from the base of the cylinder along the z-axis you need to select the vertexes at its base, cursor selection, scale it down…

Now, imagine to do this for, let’s say, 50-80 or even more cylinders. You can do that, for sure, but when the time to get the job done is 1 hour, and this is a part of the job, I believe this become a hard challenge.

Repeating that 50-80 times? I would make one, including the shape keys, animation, and then duplicate it a bunch of times, then just tweak the mesh a little in each one.
Unless each of them are dramatically different, that would speed things up considerably.

I find it not so fast to do mikahl… anyhow, mine was just an idea. As I told I can see if nobody would like or would be interested in things like this. But I would find definitely much more fast have just a growing parameter instead of setup shape keys.

Can’t recall, still always worth mentioning. :slight_smile:

You can apply a shrinkwrap modifier in projection mode to a curve and reveal it using a plane. There is no need to add another cylinder then deform it along the same curve. You can make the curve, itself, a rendered cylinder simply by increasing the bevel depth parameter. Then you can use RenResolU to control the subdivisions.

I never liked the way taper would never go completely flat. I am always left with a point on the end. BevOb should be a list, then you could do lofting 3DSMax style.

growing parameter
Blender is not really known for being a parametric based system. One of the let downs I encountered coming from 3DSMax, which is.

I’m not quite sure that the shrink wrap is actually faster, I’ll give it a try.
About the curve: it’s ok when it has to look like a simple cylinder, but what about when you have to give it a different beveling shape? After all I think this is not a problem, I cannot imagine another way to bevel it without using a beveling shape.

P.S. thumbs up for how Blender handle the beveling shape! You can reuse the same beveling object as much times as you want, of course at least you don’t need different size of the same shape or different shapes. But in Cinema4D for example, doesn’t matter if the shape it’s always the same, you have to duplicate it as much curves as you have.

That’s really the main reason why I try to stay away from Curves. However annoying this might be.

I see your point Divine, but curves are really useful in mograph. That’s why I’m trying to push this matter…

I find Blender’s curves very limiting for this type of thing. Other programs aren’t without their faults too of course. I’ve seen older versions of Maya randomly explode a curve extrusion at a given frame.

Personally, how I want to be able to deal with curves is the following:

You’d create a 3D curve object.
You’d be able to add frame pointers onto the curve that said any extrusion along it would reach this point at this frame.
You’d be able to add a bezier circle shape along the curve (not separately - it would be a curve property). These circles would be facing along the curve shape and you’d be able to edit the positions of their points. The number of points for all circles would be defined by some resolution parameter. You’d also be able to move the circles along the curve as you would with the frame pointers. The shape then just interpolates between these circles.

Both the circle positions and frame pointers should remain fixed on the curve as you edit the curve. This means that if you add CVs to the curve, it doesn’t affect your curve timing.

Interesting idea.
If I’ve got it the circles are meant to define the width of the extrusion, right?
In that case wouldn’t set radius be good as well for this purpose?
Anyhow, it’s nice to see other way to achieve similar things.

Yes they define the width but the circles can also be edited to any given bezier shape and the extrusion would interpolate between adjacent circle shapes.

So you can for example make a square cable. I know that you can already extrude a single separate bezier shape along a curve but this gives the option of multiple shapes so for example, a cylindrical curve can change into a square curve as the extrusion goes on or even into a very complex shape so long as the resolution is high enough.

Naturally, it would help if increasing the resolution didn’t affect the shape.

If you wanted the shape of a tree root for example, you’d add a circle to the end of the curve in the ground. It would then interpolate between that and the next circle. If no other circle is found, it tapers to a point where the animation end-point is defined. If you can animate this end-point (one of the frame pointer positions) then you can animate a growing root.

Say it’s a tentacle and the octopus is pushing the tentacle through a small square box. The tentacle would be cylindrical to begin with but it would need to fill the square box so you could define square extrusion inside the box and it could move back to cylindrical when it comes out or stay square.

Being able to animate the positions and shapes of the circles is useful too because you can make an animation that looks as though a bulge is moving along a pipe. Say a water hose. You would define 3 circles close to each other with the center one being larger. Then you animate their position along the curve.

Being able to view each circle shape flat would help define the shapes better too but they can maybe be loaded into the UV editor for this when selected. They’d still need to be editable in the 3D view for constraints etc.

Now I see, it works like the Loft Nurbs in Cinema 4D.
Nice tool, indeed.
Btw, I still hope some developer would find the requests here intriguing… :wink:

The Anti-Christ that is The Z-Twist

Was it this one ?

[Bf-blender-cvs] SVN commit: /data/svn/bf-blender [23019] trunk/blender/source/blender: Option to correct for 3D curve twist error.

yezz, zat waz it.

indeed, been doin the victory dance here… :slight_smile:

Model a single segment of the cylinder, add an array modifier and let the curve length control the number of segments. This way you can make the cylinder grow to arbitrary lengths without worrying about subdivisions.