A better way to animate this dynamic web

[star_space]

Hello everyone, I'm hoping to figure out a better way to achieve my desired outcome. The idea is to have a set of of lines connected to circular nodes that changes position. Think of molecules, but more of a 2D web. First I moved the nodes individually (in one layer), then I put each line on its own layer. Although now I realize that it's more than just position that I'm animating, now it's also rotation, and I also need to change the length of the lines. I'm not sure how to lengthen the line without scaling (which changes the stroke size), since I need to re-fit the line to the new space between the moved nodes.

After trying the first line, I realize that it's not just the scale that I need a solution for. Since the ends of the lines aren't attached to the nodes, there are breaks or gaps between the ends of the lines and the circular nodes before they reach their final position.

Is there not a way to animate a line getting longer without scaling? Is there no way to pin the end of the line to the circle and move them together without losing the straight lines? Hopefully there's an easier way to approach this particular challenge. Any help is greately appreciated, thank you.

[Rick Gerard · Accepted solution]

1. Create a bunch of two-point paths on a single shape layer to form the straight lines
2. Open Window/Create Nulls From Paths.jsx and select one path at a time and choose Points Follow Nulls for every point you have selected
3. Shift + Parent each null at the end of a line to the null on another null until you get the initial web pattern you want
4. Select all of the parented layers and lock them
        (You should now be able to reshape the web by simply dragging around the parented nulls)
5. Create another shape layer with a single circle at the comp center (Transform Ellipse 1/Potioin = 0, 0)
6. Duplicate Ellipse 1 (Ctrl/Cmnd + d) until you have enough circles to cover every intersection
7. Select the Ellipse 1/ Ellipse Path 1/Position and add an expression that ties the Position of the first null to the position of the first circle (example follows).

You can copy the first part of the expression and paste it and then use the Pickwhip to attach the appropriate Null position to speed things up and avoid typos. When you have it all together, you can just animate the position of each null to move the web around. 

The other option is to invest in Plexus, or Newton, or Connect Layers Pro over at AE Scripts.com. I have all three and they simplify all kinds of things, like the project you are describing, and offer lots of different options in a couple of minutes instead of a couple of hours. 

I uploaded a project file for you to look at. 

[Mylenium]

Way too convoluted for something that trivial...

Mylenium

[star_space]

Thank you so much for this thorough explanation and how-to. I'm going to try and put your solution to use today!

[Mylenium]

Effects --> Generate --> Beam

Effects --> Generate --> Circle

Connect the point controls with pickwhip expressions, transform the layer as a whole as you see fit.

Mylenium

[star_space]

Interesting. Thank you for sharing. Would this work for a lottie file, though?

[Mylenium]

Nope. But then again neither would Rick's method. This is stuff you would have to code in Animate or directly to have the lines adapt correctly.

Mylenium 

[Rick Gerard · Accepted solution]

I prefer my points follow the nulls method because it's a lot easier to grab a null and make an animation than it is to identify and grab a generated circle effect center and move it around the comp. You would at least have a chance to generate an efficient web-based file with shape layers. It's impossible with the pixels from the beam and circle effect. You gotta have vectors.