Hi Darby,
Thanks so much! That sounds very much like the exact thing I was looking for.
As I’m still a bit new to After Effects, I’m not incredibly hot at expressions. I’ll have to go do some more in-depth learning about it before I try your solution. I’m the kind of guy that would like to know what each of those parameters do before I try them out (for instance, I’m so green that I don’t even know whether the “x” in your expression is an actual value, or whether it’s just a placeholder for something that I’ll need to manually fill in). I’ve just Googled some decent looking websites dedicated to expressions, so that should give me something to sink my teeth into later tonight, letting me dissect your code.
Thanks again, Darby. I sincerely appreciate it. I’ll get back to you in a day or two to let you know how I got on.
— Sam