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iosswiftsprite-kitcgpathskshapenode

Swift: How to get the position of SKShapeNode?

I'm having trouble with SKShapeNode's position. I'm storing a path from user touch of screen. Then I create a polygon of that and put it into pathOfShapevariable. I create SKShapeNode of that path and everything works fine. I get the user drawn polygon neatly drawn on screen.

However I would like to add more stuff on the polygon. For some reason I cannot get the position of the SKShapeNode. Instead if I try to use position attribute, it points to x:0.0, y:0.0 like below. What's going one here? How can I get the actual position of my SKShapeNode? 

var pathOfShape = CGPathCreateMutable()                       
//path of polygon added here to pathOfShape
var shapeNode = SKShapeNode()
shapeNode.path = pathOfShape 
shapeNode.name = "shape"
self.addChild(shapeNode)

let node1 = self.childNodeWithName("shape")
print(node1?.position)

results to Optional((0.0, 0.0))

Solution

  • Actually if you make a CGPath, for example a triangle:

    var pathOfShape = CGPathCreateMutable()
let center = CGPointMake(CGRectGetMidX(self.frame), CGRectGetMidY(self.frame))
CGPathMoveToPoint(pathOfShape, nil, center.x, center.y)
CGPathAddLineToPoint(pathOfShape, nil, center.x + 50, center.y + 50)
CGPathMoveToPoint(pathOfShape, nil, center.x + 50, center.y + 50)
CGPathAddLineToPoint(pathOfShape, nil, center.x - 50, center.y + 50)
CGPathMoveToPoint(pathOfShape, nil, center.x - 50, center.y + 50)
CGPathAddLineToPoint(pathOfShape, nil, center.x - 50, center.y - 50)
CGPathMoveToPoint(pathOfShape, nil, center.x - 50, center.y - 50)
CGPathAddLineToPoint(pathOfShape, nil, center.x, center.y)
CGPathCloseSubpath(pathOfShape)

    enter image description here

    And you decide to create a SKShapeNode based from this path:

    let shape = SKShapeNode(path: pathOfShape)

    You could ask to get the center of this shape:

    let center = CGPointMake(CGRectGetMidX(shape.frame),CGRectGetMidY(shape.frame))

    The correct position is always (0.0, 0.0) but almost you know where is your shape.