Whenever the user zoom in or out the map i need to know how many meters are currently represented on the map (width or height).
What i need is the inverse function of MKCoordinateRegionMakeWithDistance to calculate the distance represented by the current map span.
I tried the following code but i get wrong results :
- (void)mapView:(MKMapView *)mapView regionDidChangeAnimated:(BOOL)animated {
MKMapRect mRect = self.map.visibleMapRect;
MKMapPoint northMapPoint = MKMapPointMake(MKMapRectGetMidX(mRect), MKMapRectGetMinY(mRect));
MKMapPoint southMapPoint = MKMapPointMake(MKMapRectGetMidX(mRect), MKMapRectGetMaxY(mRect));
self.currentDist = MKMetersBetweenMapPoints(northMapPoint, southMapPoint);
}
If i set the map region to 1500 meters i get something like 1800 as a result..
Thanks for your help, Vincent
Actually it was a really stupid mistake, if i do the same operation along the X axis then i get the correct value :
- (void)mapView:(MKMapView *)mapView regionDidChangeAnimated:(BOOL)animated {
MKMapRect mRect = self.map.visibleMapRect;
MKMapPoint eastMapPoint = MKMapPointMake(MKMapRectGetMinX(mRect), MKMapRectGetMidY(mRect));
MKMapPoint westMapPoint = MKMapPointMake(MKMapRectGetMaxX(mRect), MKMapRectGetMidY(mRect));
self.currentDist = MKMetersBetweenMapPoints(eastMapPoint, westMapPoint);
}