invert method
Inverts screen coordinates to geographic longitude, latitude.
Implementation
@override
(double, double) invert(double x, double y) {
final (rawX, rawY) = removeTransform(x, y);
final longitude = toDegrees(rawX) + centerLon;
final latitude = toDegrees(2 * math.atan(math.exp(-rawY)) - math.pi / 2);
return (clampLongitude(longitude), clampLatitude(latitude));
}