how to set anchorPoint of view to 0.5 , 0.5 to get view in centre of screen? (Not scene)

Question

I want to make my game full screen not with the black bars on both sides and bottom. so I found this code for that and it works for scene and now it's on full screen but the assets are not correctly positioned. Because of the view's coordinates are different (don't know why maybe because of previously I tried to set all for safeAreaLayoutGuide but then I get black bars). So is there any way to set it back to 0.5 0.5 . Otherwise I will have to set back anchorPoint of scene to what ever is view's anchorPoint and set all assets in my sks file according to that.

Here is the code from GameViewController :

class GameViewController: UIViewController {

    override func viewWillLayoutSubviews() {
        super.viewWillLayoutSubviews()

        if let view = self.view as! SKView? {
            view.ignoresSiblingOrder = true
            view.showsFPS = true
            view.showsNodeCount = true

            let scene = HomeScene(size: view.bounds.size)
            scene.scaleMode = .aspectFill
            view.presentScene(scene)
        }
    }

    override func viewDidLoad() {
        super.viewDidLoad()

        print("---")
        print("∙ \(type(of: self))")
        print("---")
    }
}

this code from HomeScene :

let rectangle1 = SKShapeNode(rect: (self.view?.bounds)!)
rectangle1.strokeColor = .white
rectangle1.lineWidth = 20
addChild(rectangle1)

// Set (0, 0) as the centre of the screen
scene?.anchorPoint = CGPoint(x: 0.5, y: 0.5)

let rectangle = SKShapeNode(rect: self.frame)
rectangle.strokeColor = .green
rectangle.lineWidth = 20
addChild(rectangle)

This is how it looks the scene is at 0.5, 0.5 but, view is above that green is scene and white is view and button in middle of the view :

Thank you.

Natarajan your answer is gone because of edit can you please answer it again. — Ramesh Sanghar, Jan 02 '19 at 10:42
Thanks Alexandru and .P van der laan for your answers. I did something else but it will help many others. — Ramesh Sanghar, Mar 12 '19 at 04:34

score 2 · Accepted Answer · answered Jan 05 '19 at 18:56

You could fix the problem with a different anchorpoint, or you could position the white 'view' node differently in the scene.

Information about the coordinate system (and anchor points): apple documentation

The default anchor position is (0.5, 0.5) according to the documentation. To put the white view in the bottom left: subtract half of the width and height of the x and y. Note that the line width also affects the positioning. Position the white view to the bottom left:

let bottomLeft: CGPoint = CGPoint(x: -self.size.width/2 + rectangle1.lineWidth/2,
                                  y: -self.size.height/2 + rectangle1.lineWidth/2)
rectangle1.position = bottomLeft

To center the white view in the green view, subtract the width and height of rectangle1 (again, note the line width)

let center: CGPoint = CGPoint(x: -rectangle1.frame.size.width/2 + rectangle1.lineWidth/2,
                              y: -rectangle1.frame.size.height/2 + rectangle1.lineWidth/2)
rectangle1.position = center

Note that your green view is above the white view. Set the z position of the white view to some positive number to arrange it above the green view

rectangle1.zPosition = 1

score 2 · Answer 2 · answered Jan 16 '19 at 07:54

If you were loading your HomeScene from a .sks file, the anchorPoint was set by xcode to (0.5, 0.5) as shown in my image.

But when you are trying to create a custom class without loading it from file (.sks), you will not have the properties set like here. So you need to set the manually.

let scene = HomeScene(size: view.bounds.size) 
// at this point, you HomeScene has the anchorPoint set to (0.0, 0.0)

// lets set it back to (0.5, 0.5) as we want
scene.anchorPoint = CGPoint(x: 0.5, y: 0.5)
scene.scaleMode = .aspectFill
view.presentScene(scene)

how to set anchorPoint of view to 0.5 , 0.5 to get view in centre of screen? (Not scene)

2 Answers2