Yes, but this seems to be convoluting two distinct problems. one is how to handle user inputs to a camera/world with inertia while moving whith a lot more vari

Yes, but this seems to be convoluting two distinct problems. one is how to handle user inputs to a camera/world with inertia while moving whith a lot more variables to set for a certain desired feel, (why no long taps/mousedown to speed up the movement). While the button is just easing a fixed animation between two states with no intermediate input. Also what happens to the binary state of the app if the animation can be reversed before reaching final state, this is opening a can of worms for no obvious reason.