How to animate a cylinder in on itself?

Hiya guys,

I’ve added a picture because I have no idea how to properly describe what I’m after.


How would I achieve this kind of animation?
The idea is to make a ‘jump-gate’ effect. I thought If I could animate this cylinder in such a way I could add a texture and have it move down the length and back on itself.

Any ideas guys?

Attachments


If you want to animate the geometry itself, you can think of your tube as a stretched-out torus. The torus in turn is made of a line of cylinders, curved into a circle. You can make something like your shape from one cylinder with array, curve, and lattice modifiers added to it in turn, like this crude example:


Select the highly modified cylinder object and rotate on its (local) Z axis, and you’ll get the motion you want.

Notes on construction:
Make sure the 3D cursor is always at the world origin for all these procedures.
Add the original cylinder in Top view, so the global Z axis is parallel to its long axis. Remove the end faces.
The Array modifier should be set to offset along Z.
Add a Bezier circle and use it as a Curve modifier on the arrayed cylinder. Adjust the array count so the cylinder segments go all the way around to form a torus.
Add a Lattice and use it as a Lattice modifier on the cylinder. In Edit mode, scale the Lattice on its Z axis to stretch the torus into an open cylinder.

You can UV unwrap the original cylinder to add a texture, but the texture would be highly distorted by all the modifications. I guess you could start with an already distorted texture; I haven’t tried it myself yet.

You could also dispense with the array modifier and start with an elongated, subdivided cylinder. It might be easier to texture, although you’d still have the stretching problems.

Here is a .blend file showing the rudiments: WRING torus.blend (488 KB)

I got interested in this inside-out/wringing effect while thinking about the end of Terminator 2, when the T-1000 is writhing around in the molten steel. The character turns inside out through its mouth while morphing into shapes it mimicked earlier. I’m still trying to get my head around how to simulate something like that in Blender.

CD38 thank you very much for the detailed post. It’s not quite the effect I’m after as the animation would have to be steady and constant but it’s very interesting indeed. I wish I was as good at problem solving as you obviously are.

Thank you, and I’m sorry it doesn’t work for you. Can you clarify what you mean by the animation being “steady and constant”? With this setup you can extrapolate a linear animation curve for the local Z rotation of the unit cylinder and have the wringing motion go on forever.

An alternate method is to keep the cylinder geometry fixed and animate the texture.

The first comment went over my head and that’s most probably the problem, my inexperience with this type of thing. Having an animated texture might work. Just paint a few streaks on a long texture? and somehow make the animation loop?

Ok. So this is the plan so far…

Fixed cylinder that will rotate slowly. A proceedural texture applied to the cylinder.

2 questions.

  1. Is it possible to animate the textures and if so how to make it in just one axis…say the y axis.

  2. Is it necessary to mark a seem on the cylinder as im pretty sure thay will ness up the seemless aspect. Or am i wrong?

Ok. So this is the plan so far…

Fixed cylinder that will rotate slowly. A proceedural texture applied to the cylinder.

2 questions.

  1. Is it possible to animate the textures and if so how to make it in just one axis…say the y axis.

  2. Is it necessary to mark a seem on the cylinder as im pretty sure thay will ness up the seemless aspect. Or am i wrong?

Ok. So this is the plan so far…

Fixed cylinder that will rotate slowly. A proceedural texture applied to the cylinder.

2 questions.

  1. Is it possible to animate the textures and if so how to make it in just one axis…say the y axis.

  2. Is it necessary to mark a seem on the cylinder as im pretty sure thay will ness up the seemless aspect. Or am i wrong?

Ok. So this is the plan so far…

Fixed cylinder that will rotate slowly. A proceedural texture applied to the cylinder.

2 questions.

  1. Is it possible to animate the textures and if so how to make it in just one axis…say the y axis.

  2. Is it necessary to mark a seem on the cylinder as im pretty sure thay will ness up the seemless aspect. Or am i wrong?

Ahhh this always happens when i post from my phone. Sincere appologies for spam…

  1. Yes you can animate texture position and rotation on selected axes. The exact method differs slightly depending which renderer you’re using and how you’ve mapped the texture.

  2. If you UV unwrap the cylinder you’ll want a seam for easiest texture mapping. If you use the modified cylinder technique I described, your texture would have to be seamless both vertically and horizontally no matter what mapping you use. The texture’s edges would wrap around the sides of the cylinder to meet, and the modifiers mean the texture would repeat, meeting at the cylinders’ open ends.

You can easily make any animation loop/repeat by using the Graph Editor and changing the extrapolation. See the Blender manual.

If I can find time today I’ll try to work up a textured example for you.

That would be great, appreciate it :smiley:

Below is a crude .blend file showing how to use an animated texture to achieve your effect in Cycles. I was lazy and applied all the modifiers in the above file to make the shape, but you could easily model it yourself.
Basically I mapped a texture to the UV-wrapped mesh and animated the X coordinate. Let me know if you have any questions.

Texture Torus.blend (582 KB)

That is exactly what I’m after! Thank you very much, I’ll try and replicate what you did :smiley: