Properly Converting a point in `SKScene` to a location for a `UIView`

Question

I have a UIView that I want to position on top of a certain area in an SKScene.

This is the point that I have in my SKScene:

 guard let point = elementCGPoints.centroid() else {
        return
    }

And I'm trying to use this SKView method to convert from scene coordinates to view coordinates; based on this SO discussion:

    let convertedPoint = canvasScene.convertPoint(toView: point)
    
    selectionBox.frame = CGRect(x: convertedPoint.x, y: convertedPoint.y, width: 100, height: 100)

However, this ends up always displaying at a point far beyond the range of my view.

Any intuition about how to do this right?

Answer 1

here are two ways. the first is responding to UITouch inside SKScene

override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
    guard let touch = touches.first else { return }
    let locationInWindow = touch.location(in: touch.window)
    let locationInView = touch.location(in: self)
    gameSceneDelegate?.moveView(toPosition: locationInWindow) //move a UIView to window position (via delegate pattern)
    shape.position = locationInView //move a SKNode to same position in scene
}

this is easiest. but your question suggests you want to use convertPoint in which case you could convert an arbitrary point from scene to view like this

//inside SKScene
let random_point = CGPoint(x: CGFloat.random(in: 0...100), y: CGFloat.random(in: 0...100))
let converted_point = self.convertPoint(toView: random_point)
gameSceneDelegate?.moveView(toPosition: converted_point) //move a UIView to window position (via delegate pattern)
shape.position = random_point //move a SKNode to same position in scene

and the UIViewController delegate would look like this

protocol GameSceneDelegate : UIViewController {
    func moveView(toPosition position:CGPoint)
}

class GameViewController: UIViewController, GameSceneDelegate {
    [...]
    func moveView(toPosition p:CGPoint) {
        myView?.frame.origin = p
    }
}