gistify469120.m

  CAShapeLayer *maskLayer = [[CAShapeLayer alloc] init];
        CGRect maskRect = self.coneImageView.frame;
        NSLog(@"Mask rect is %@", NSStringFromCGRect(maskRect));
        // Create a path with the rectangle in it.
        CGPathRef path = CGPathCreateWithRect(maskRect, NULL);
        
        // Set the path to the mask layer.
        maskLayer.path = path;
        
        // Release the path since it's not covered by ARC.
        CGPathRelease(path);
        
        // Set the mask of the view.
        self.connectorLine.layer.mask = maskLayer;