If true, panning will always be animated if possible.
If false, it will not animate panning, either resetting the map view
if panning more than a screen away, or just setting a new offset for
the map pane (except for panBy which always does the latter).
The curvature factor of panning animation easing (third parameter of the Cubic Bezier curve).
1.0 means linear animation, and the smaller this number, the more bowed the curve.