Inertia effect to end pan

[Seiifer]

Hello,

I was thinking about adding the inertia effect when panning the SVG.
By Inertia effect I mean that after we are done panning, the pan continues for a few milliseconds at a slower (ideally decreasing) speed.
If you are wondering how it would look like, check on Google Map, they use this effect when panning.

I'm not quite sure how to achieve that.
Maybe if there were a afterPan function, but I don't really see how to get the speed of the mouse (unless we just check the time and the distance between the 2 clicks that triggered the pan.)
Or maybe by calling panBy after each pan but the direction of the pan is also needed.

[bumbu]

Currently there is no such functionality and there is no plan for that.
It can be an idea for a plugin as per #98 but someone has to build that.

You could do that by listening for onPan callbacks, but it will not give you any information about when pan ended (as user may still hold the click even if he is not moving the mouse).
A solution would be to handle mouse events by yourself (as in [custom events](Custom events example)). There you'll have to compute by yourself velocity and direction of drag. After mouseup/touchend you'll have to call pan/panBy as long as you want your inertia to execute.