question: public float computeScale ( ) { double kmPerInch = 0.0254e-3 ; double kmPerDeg = Position . EARTH_RADIUS * Math . toRadians ( 1.0 ) ; return ( float ) ( dotsPerDeg / dotsPerInch * kmPerInch / kmPerDeg ) ; }
target:  Returns the scale. 1 / 100 000 means one cm on the screen corresponds to 1 km in real world. 