Growing along path animation


Can’t seem to figure out how to animate the growth of an object (say a vertex, a rectangle, a cube) along a given path (curve, straight line, polyline, …). The idea is to make it appear out of nowhere and “grow” along the given path, in the way of what would happen if you hit the S key and constrained size of an object to just one dimension (x, y or z), with the added difficulty of having to adhere to the trajectory of a specific path.
When modeling you have extrusion along a path, but i’m not sure you can animate an extrusion… can you?

I’m sure it’s something relatively east to do, but i’m overwhelmed by now… Could someone point me in the right direction ??


You could create an IPO curve for the size and set it to go until a certain frame. Have that certain frame go past the amount of frames your animating for that will give you a continuous growing effect. Or if you want it to do certain growth and and shrink effect just change the direction of the curve/constant line.

Also if you want it to go along a path then just track it to a path.

If your talking about growth as in a plant your going too complicated for me. I would think that if its a plants growth then you might be better off animating it yourself unless you get really clever.

Thanks for your reply Bobfree!
What I’m looking for is described in the picture below.
Now, I would like to be able to do it in 2 different ways:

  1. Starting out with just one vertex, making it repeat itself along the path (is it feasible in Blender?)
  2. Using a cube or a cylinder to behave in the exact same manner.

Thanks for your input


Yes, you can do that in Blender!

Check out the Build Modifier found in the Editing buttons window. I’m assuming you know how to create your model. After that, add a Build modifier and play the animation to see the effects. Tweak as needed.

If it’s just along a path / line try using a curve with an animated taper

Thanks for your input. I went with the Build modifier method:

  1. Imported an SVG path from elsewhere
  2. Converted the path to mesh in Blender
  3. Added build modifier

It is very close to what I want but ran into a few quirks:

  1. Sometimes a few dots (vertices) seem not to render
  2. Due to the fact that vertex distribution is not uniform along the path, it grows at an uneven rate, when in fact I’d like it to grow at a steady speed.
    How could I have a path with homogenous vertex distribution?

A few frames from my text animation:


I meant test animation…

This is a draft of the steps to use to get uniform distribution of vertices along a path:

  • Import your SVG path or create it in Blender
  • create a plane and delete all but one of the vertices
  • “centre new” that vertex
  • have the vertex follow the path of the curve with dupliframes
  • move the original vertex around to tweak the dupliframes
  • make the dupes “real”
  • select all the dupes and join them into one mesh

At that point, Stirfry (that’s making me hungry BTW :)), you can apply the Build modifier to the new mesh.

I’ve seen this problem enough times that I’ll create a step-by-step tutorial (probably HTML-based or PDF) this weekend and post it on my site.

Hope that helps.

Brilliant! Right on the money!
Thanks kernond. Great website, by the way!

Case closed. See you all soon.

Thanks! :slight_smile:

Sorry if this is a dumb question, but how do you make the verts “real” as you suggest :confused: :smiley: