Swift: SKConstraint for scale? (or equivalent) Stuttering

Question

At the minute I'm using the SKConstraint.positionX(rangex, y: rangey) to confine my SKCameraNode within the game board I've created. This is nice because when you hit the boundary there's no stuttering. But my current way to cap the scale of the camera creates a stutter as it hits the bound as it goes past and pings back.

    @objc func zoomedView(_ sender:UIPinchGestureRecognizer) {
        if newCamera.xScale > 0.148{
            let pinch = SKAction.scale(by: 1/sender.scale, duration: 0.0)
            newCamera.run(pinch)
            sender.scale = 1.0
        } else {newCamera.setScale(0.148)}
    } 

Is there an SKConstraint for scale (or equivalent) which is a better way to stop this stutter? Thanks :)

Answer 1

There is no direct SKConstraint equivalent for scale, however the reason you're experiencing the stuttering is as you go over the bound it snaps back the next time the function is called, rather before a frame is rendered, so theoretically you could zoom in massively instantaneously, and stay there until you activate the zoom function again.

A way to create an equivalent is to put the code checking whether the scale is greater than x in the rendering loop as outlined here.

So if you were to check at the last possible moment:

override func didFinishUpdate() {
    if newCamera.xScale < 0.148{
        newCamera.setScale(0.148)
    } else if newCamera.xScale > 10{
        newCamera.setScale(10)
    }
}