I have a UIView containing some points within, and I make it rotate according to the readings from magnetometer via CLLocationManager, as follow:
@interface PresentationVC () {
float initialBearing;
}
@end
@implementation PresentationVC
- (void)viewDidLoad {
self.locationManager = [[CLLocationManager alloc] init];
self.locationManager.delegate = self;
[self.locationManager startUpdatingHeading];
[self.locationManager startUpdatingLocation];
}
#pragma mark - CLLocationManager Delegate
- (void)locationManager:(CLLocationManager *)manager didUpdateHeading:(CLHeading *)newHeading {
if(initialBearing == 0) {
initialBearing = newHeading.magneticHeading;
}
NSLog(@"Magnetic Heading: %f", newHeading.magneticHeading);
viewMap.transform = CGAffineTransformMakeRotation(degreesToRadians(initialBearing - newHeading.magneticHeading));
}
@end
where viewMap is the UIView.
The above code works, but I want the transform of UIView set to 0 degree / radian, which is CGAffineTransformMakeRotation(0). Currently it sets to current bearing initially, which is, for example, 157 degree.
I try to use initialBearing in the above code to calculate the offset angle, but it still rotates to an angle initially. What did I miss?
Also, I can't rotate a full 360 degree; the CGAffineTransformMakeRotation() bounces back the rotation when I turn almost 180 degree instead. How can I rotate a full 360 degree rotation without bouncing? (I guess it's about radian degree issue)
