I've done this in the past but can't locate my old project, and my head is throbbing from last nite.....
I'd like to apply an expression to my null's position. I want it to pan horizontally at a speed specified with a slider control. I'd like it to be able to start, stop, and then continue. Doesn't need to ease in, but it'd be nice.
Speed = effect("Speed")("Slider");
OffsetX = effect("Offset")("Point");
fps = 24;
x = OffsetX - (Speed * time * fps);
My problem multiplying "speed" with time means that when it stops (speed=0), it returns to the start position.... I need it to stay in place, and then continue when I animate the speed value back up.