Drawing circle outline with small gap Sprite Kit Swift

Question

I am currently creating a game in SpriteKit. In this game, I am trying to draw an outline of a circle with a small gap(s) in the outline of this circle (possibly about 1/8 the entire circumference of the circle). Here is a drawn picture of what I am visualizing.

How would I do this using SpriteKit? Would I use SKShapeNode? Any help would be appreciated. Thank you.

score 3 · Accepted Answer · answered Mar 19 '16 at 03:39

You can get something similar using the SKShapeNode in combination with SKEffectNode, like this:

override func didMoveToView(view: SKView) {

        let effectNode = SKEffectNode()
        let gap = CGFloat(M_PI_4 / 4.0)

        for i in 0...3 {

            let shape = SKShapeNode(circleOfRadius: 50)

            shape.fillColor = .clearColor()
            shape.lineWidth = 6.8
            shape.strokeColor = .darkGrayColor()

            let startAngle:CGFloat = CGFloat(i) * CGFloat(M_PI_2) + gap
            let endAngle:CGFloat = startAngle + CGFloat(M_PI_2) - gap * 2

            print("Iteration \(i) : start angle (\(startAngle * 180 / CGFloat(M_PI)), end angle (\(endAngle  * 180 / CGFloat(M_PI)))")

            shape.path = UIBezierPath(arcCenter: CGPointZero, radius: -50, startAngle: startAngle, endAngle: endAngle, clockwise: true).CGPath

            effectNode.addChild(shape)
        }

        effectNode.position = CGPoint(x: frame.midX, y: frame.midY)
        effectNode.shouldRasterize = true

        addChild(effectNode)
}

The result:

Or you could make a mask programatically and apply it to a SKCropNode. The SKCropNode of course will be a parent of a ring (SKShapeNode with fillColor set to .clearColor() and strokeColor set to appropriate value).

Drawing circle outline with small gap Sprite Kit Swift

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