In After Effects, I want to animate an object from a position A = (960, 540), being the center of my 1920x1080 composition, to a position B = (960 - offset, 540) to the left, where offset is a positive number. My composition will be used as Motion Graphics template, so this offset needs to be adjustable with a Slider Control so that users can tweak the amount of movement.
In this question, a method is shown where a slider can be used to interpolate between two positions. However, I want to have the temporal interpolation to be predefined, and it is more complicated than the simple linear or ease interpolation that expressions allow for.
Thus, I want to be able to set the keyframe values with the slider, but I want the keyframe interpolation to be done with the graph editor. How can I make this work?