sora0077

import MapKit

// http://troybrant.net/blog/2010/01/set-the-zoom-level-of-an-mkmapview/

private let mercadorRadius: Double = 85445659.44705395
private let mercadorOffset: Double = 268435456

private func longitudeToPixelSpaceX(longitude: Double) -> Double {
    return round(mercadorOffset + mercadorRadius * longitude * .pi / 180.0);
}