The animations below show the mainspring being unwound from the perspective of the arbor wheel (and God) and wound from the perspective of the barrel.
Note that the barrel and its arbor rotate clockwise in order to rotate the center wheel and hands anti-clockwise.
Unwinding Relative to the Arbor Wheel:
the barrel rotates clockwise.
Winding Relative to the Barrel:
the arbor rotates clockwise.