ios实现简单随便移动的AR功能

//两点的经纬度计算距离 
-(float) DistanceFromCoordinates:(CLLocationCoordinate2D) myDot other:(CLLocationCoordinate2D)otherDot 
{ 
  
 double EARTH_RADIUS = 6378137.0; 
  
 double radLat1 = (myDot.latitude * M_PI / 180.0); 
 double radLat2 = (otherDot.latitude * M_PI / 180.0); 
 double a = radLat1 - radLat2; 
 double b = (myDot.longitude - otherDot.longitude) * M_PI / 180.0; 
 double s = 22 * asin(sqrt(pow(sin(a / 2), 2) 
        + cos(radLat1) * cos(radLat2) 
        * pow(sin(b / 2), 2))); 
 s = s * EARTH_RADIUS; 
 s = round(s * 10000) / 10000; 
  
 return s; 
  
} 

- (float)getHeadingForDirectionFromCoordinate:(CLLocationCoordinate2D)fromLoc toCoordinate:(CLLocationCoordinate2D)toLoc 
{ 
 float fLat = DegreesToRadians(fromLoc.latitude); 
 float fLng = DegreesToRadians(fromLoc.longitude); 
 float tLat = DegreesToRadians(toLoc.latitude); 
 float tLng = DegreesToRadians(toLoc.longitude); 
  
 float degree = RadiansToDegrees(atan2(sin(tLng-fLng)*cos(tLat), cos(fLat)*sin(tLat)-sin(fLat)*cos(tLat)*cos(tLng-fLng))); 
  
 if (degree >= 0) { 
  return degree; 
 } else { 
  return (360+degree); 
 } 
 
} 

-(void) startMotion 
{ 
  
 if (![_mgr isDeviceMotionActive] && [_mgr isDeviceMotionAvailable]) 
 { 
   
 //设置采样间隔 
  _mgr.deviceMotionUpdateInterval = 0.1; 
 
 NSOperationQueue *queue = [[NSOperationQueue alloc] init]; 
 
  [_mgr startDeviceMotionUpdatesToQueue:queue 
   withHandler:^(CMDeviceMotion * _Nullable motion, 
      NSError * _Nullable error) { 
          
      double gravityX = motion.gravity.x; 
      double gravityY = motion.gravity.y; 
      double gravityZ = motion.gravity.z; 
          
          
   if (gravityY<=0 && gravityY>=-1) 
   { 
           
 //获取手机的倾斜角度(zTheta是手机与水平面的夹角， xyTheta是手机绕自身旋转的角度)： 
  zTheta = atan2(gravityZ,sqrtf(gravityX*gravityX+gravityY*gravityY))/M_PI*180.0; 
 
} 
  [[NSOperationQueue mainQueue] addOperationWithBlock:^{     
    [self updataPoint]; 
 
    }]; 
       
  //[self performSelectorOnMainThread:@selector(updataPoint) withObject:nil waitUntilDone:NO]; 
      
  }]; 
     
 } 
}