Quartz Composer: How to make a line bend

Question

I'm trying to make a straight vertical line which, when you drag across on the X axis, will bend a bit like an elastic band and snap back when you let go.

I've made a quick image mock up of what I'm trying to do, here https://dl.dropboxusercontent.com/u/57554153/Line.png

I'm really trying to figure out if you can actually bend the lines or if I have to fake it with a bunch of points instead. Just trying to prototype some animations for an app.

Thanks!

Answer 1

I suggest you try with the Kineme Spline Patch (www.kineme.net) and play with the control points and ratios with your X position.

The upper and lower points of your pline could be fixed, while you'd have 3 points moving :

• 1st : x * 0.25, y = 0.75 * view height
• 2nd : x * 0.5, y = 0.5 * view height
• 3rd : x * 0.25, y = 0.25 * view height