Question

I have a CLLocation defined, and I’d like to move that point x meters to the east and y meters to the south. How may I achieve that?

Answer 1

There is a C function that is close to what you are asking but it takes a bearing and distance. It’s in my UtilitiesGeo class on github. You would pass the latitude and longitude from your CLLocation to it and then create a new CLLocation from the resulting lat2 and lon2 that it returns:

/*-------------------------------------------------------------------------
* Given a starting lat/lon point on earth, distance (in meters)
* and bearing, calculates destination coordinates lat2/lon2.
*
* all params in degrees
*-------------------------------------------------------------------------*/
void destCoordsInDegrees(double lat1, double lon1,
                         double distanceMeters, double bearing,
                         double* lat2, double* lon2);

If you can’t use that, take a look at the algorithms that it was derived from here and here and perhaps you can modify it or those sites might have something closer to your needs.