-(void) setImage:(UIImage*)image;
-(void) setImageWithName:(NSString*)fileName;  // path or bundle. will check at both

 // auto-update (usually only one of these at a time is recommended)
-(void) setOrientToDevice:(BOOL)   // activate motion sensors
-(void) setTouchToPan:(BOOL)       // activate UIPanGesture

 // aligns z-axis (into screen)
-(void) orientToVector:(GLKVector3)
-(void) orientToAzimuth:(float) Altitude:(float)

-(void) setFieldOfView:(float)     // in degrees
-(void) setPinchToZoom:(BOOL)      // activate UIPinchGesture

-(void) setShowTouches:(BOOL)      // overlay latitude longitude intersects
-(BOOL) touchInRect:(CGRect)       // hotspot detection in world coordinates

-(CGPoint) screenLocationFromVector:(GLKVector3) // 2D screen point from a 3D point
-(GLKVector3) vectorFromScreenLocation:(CGPoint) // 3D point from 2D screen point
-(CGPoint) imagePixelAtScreenLocation:(CGPoint)  // 3D point from 2D screen point
  // except this 3D point is expressed as 2D pixel unit in the panorama image

panoramaView = [[PanoramaView alloc] init];
 // load image and any other customization
[self setView:panoramaView];

-(void) glkView:(GLKView *)view drawInRect:(CGRect)rect{
    [panoramaView draw];
}

class MainView: GLKViewController {
    
    var panoramaView = PanoramaView()
    
    override func viewDidLoad() {
        panoramaView.setImageWithName("imagename.jpg")
        panoramaView.touchToPan = true          // Use touch input to pan
        panoramaView.orientToDevice = false     // Use motion sensors to pan
        panoramaView.pinchToZoom = true         // Use pinch gesture to zoom
        panoramaView.showTouches = true         // Show touches
        self.view = panoramaView
    }
    
    override func glkView(view: GLKView, drawInRect rect: CGRect) {
        panoramaView.draw()
    }
}