compass-geolocation

I calculated the wind direction and now I want to show the wind direction pointing to 144 degrees (on compass). How can I show this arrow on Google Maps? In order to show an arrow over a google map you can create a Rich Marker that embed an image using the google-maps-utility-library-v3 , Next apply a rotation in degree to the image element with css3 tranformations. In example : // content element of a rich marker var richMarkerContent = document.createElement('div'); // arrow image var arrowImage = new Image(); arrowImage.src = 'http://www.openclipart.org/image/250px/' + 'svg_to_png/Anonymous

I've been experimenting with the compass and gyroscope on iPhone 4 and would like some help with an issue I'm having. I want to compensate for the slowness of the compass by using data from the gyroscope. Using CMMotionManager and its CMDeviceMotion object ( motionManager.deviceMotion ), I get the CMAttitude object. Correct me if I'm wrong (please), but here is what I've deduced from the CMAttitude object's yaw property (I don't need pitch nor roll for my purposes): yaw ranges from 0 to PI when the phone is pointing downwards (as indicated by deviceMotion.gravity.z ) and swinging

In my app I have a latitude-longitude of 1 fix location. Now user with iPhone device can move anywhere and even he rotate his device, the arrow (some uiimageview) should point to that fix location so User will get direction to that location every time. I tried as follows. -(void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation { CLLocationCoordinate2D here = newLocation.coordinate; [self calculateUserAngle:here]; } -(void) calculateUserAngle:(CLLocationCoordinate2D)user { NSLog(@"my destination is %f ; %f",

I'm working on a "compass" for a mobile-device. I have the following points: point 1 (current location): Latitude = 47.2246, Longitude = 8.8257 point 2 (target location): Latitude = 50.9246, Longitude = 10.2257 Also I have the following information (from my android-phone): The compass-direction in degree, wich bears to the north. For example, when I direct my phone to north, I get 0° How can I create a "compass-like" arrow wich shows me the direction to the point? Is there a mathematic-problem for this? thanks! EDIT: Okay I found a solution, it looks like this: /** * Params: lat1, long1 =>