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copied!<p>I ended up with a completely different strategy. Instead of adding by own overlay I now rely on <code>MKPolyLine</code>.</p> <p>Using the following code I'm able to add a pseudo animated line from point A to point B on a <code>MKMapView</code>. </p> <p>The code adds several overlays to the MKMapViews with a slight delay, giving the impression of an animation</p> <p>Not the most beautiful solution! - but it looks pretty good in action :-)</p> <pre><code>/*start the animation*/ -(void)plotRouteOnMap { [self.mapView removeOverlays:self.mapView.overlays]; //calculate a number locations between the two locations self.points = [self getPointsOnRouteFrom:<FROM_LOCATION> to:<TO_LOCATION> onMapView:self.mapView]; [self addOverlaysFromPointsWithStartFrom:[NSNumber numberWithInt:1]]; } /*convert a CGPoint to a CLLocation according to a mapView*/ - (CLLocation*)pointToLocation:(MKMapView *)mapView fromPoint:(CGPoint)fromPoint { CLLocationCoordinate2D coord = [mapView convertPoint:fromPoint toCoordinateFromView:mapView]; return [[[CLLocation alloc] initWithLatitude:coord.latitude longitude:coord.longitude] autorelease]; } /*get a list of Location objects between from and to*/ -(NSArray*)getPointsOnRouteFrom:(CLLocation*)from to:(CLLocation*)to onMapView:(MKMapView*)mapView { int NUMBER_OF_PIXELS_TO_SKIP =10; //lower number will give a more smooth animation, but will result in more layers NSMutableArray *ret = [NSMutableArray array]; CGPoint fromPoint = [mapView convertCoordinate:from.coordinate toPointToView:mapView]; CGPoint toPoint = [mapView convertCoordinate:to.coordinate toPointToView:mapView]; NSArray *allPixels = [self getAllPointsFromPoint:fromPoint toPoint:toPoint]; for (int i = 0 ; i < [allPixels count] ; i+=NUMBER_OF_PIXELS_TO_SKIP) { NSValue *pointVal = [allPixels objectAtIndex:i]; [ret addObject:[self pointToLocation:mapView fromPoint:[pointVal CGPointValue]]]; } [ret addObject:[self pointToLocation:mapView fromPoint:toPoint]]; return ret; } /*calulate alle pixels from point to toPint*/ -(NSArray*)getAllPointsFromPoint:(CGPoint)fPoint toPoint:(CGPoint)tPoint { /*Simplyfied implementation of Bresenham's line algoritme */ NSMutableArray *ret = [NSMutableArray array]; float deltaX = fabsf(tPoint.x - fPoint.x); float deltaY = fabsf(tPoint.y - fPoint.y); float x = fPoint.x; float y = fPoint.y; float err = deltaX-deltaY; float sx = -0.5; float sy = -0.5; if(fPoint.x<tPoint.x) sx = 0.5; if(fPoint.y<tPoint.y) sy = 0.5; do { [ret addObject:[NSValue valueWithCGPoint:CGPointMake(x, y)]]; float e = 2*err; if(e > -deltaY) { err -=deltaY; x +=sx; } if(e < deltaX) { err +=deltaX; y+=sy; } } while (round(x) != round(tPoint.x) && round(y) != round(tPoint.y)); [ret addObject:[NSValue valueWithCGPoint:tPoint]];//add final point return ret; } /*add a poly line overlay to mapview which start at position 0 and end in 'end' in the array points*/ -(void)addOverlaysFromPointsWithStartFrom:(NSNumber*)end { int intEnd = [end intValue]; //construct polyline view from start CLLocationCoordinate2D *locations = malloc(sizeof(CLLocationCoordinate2D)*2); CLLocation *loc1 = (CLLocation*)[points objectAtIndex:0]; CLLocation *loc2= (CLLocation*)[points objectAtIndex:intEnd]; locations[0] = loc1.coordinate; locations[1] = loc2.coordinate; MKPolyline *line = [MKPolyline polylineWithCoordinates:locations count:2]; [self.mapView addOverlay:line]; if((intEnd+1) < [points count])//add more overlays after delays unless this is the endpoint { [self performSelector:@selector(addOverlaysFromPointsWithStartFrom:) withObject:[NSNumber numberWithInt:intEnd + 1] afterDelay:0.01]; } } </code></pre>

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