Create a line with two CGPoints SpriteKit Swift

Question

I am trying to make a simple app where you touch a point, and a sprite follows a line through that point to the edge of the screen, no matter where you touch. I want to draw lin

Answer 1

Follow THIS tutorial step by step and you can achieve that.

Consider the below code:

override func touchesMoved(touches: NSSet, withEvent event: UIEvent) {
    let location = touches.anyObject()!.locationInNode(scene)
    if let pig = movingPig {
        pig.addMovingPoint(location)
    }
}

This is a simple method. You get the next position of the user’s finger and if you found a pig in touchesBegan(_:,withEvent:), as indicated by a non-nil movingPig value, you add the position to this pig as the next waypoint.

So far, you can store a path for the pig—now let’s make the pig follow this path. Add the following code to update() inside GameScene.swift:

dt = currentTime - lastUpdateTime
lastUpdateTime = currentTime

enumerateChildNodesWithName("pig", usingBlock: {node, stop in
    let pig = node as Pig
    pig.move(self.dt)
})

And you can see result:

Drawing Lines:

At the moment, only the pig knows the path it wants to travel, but the scene also needs to know this path to draw it. The solution to this problem is a new method for your Pig class.

func createPathToMove() -> CGPathRef? {
    //1
    if wayPoints.count <= 1 {
        return nil
    }
    //2
    var ref = CGPathCreateMutable()

    //3
    for var i = 0; i < wayPoints.count; ++i {
         let p = wayPoints[i]

    //4
    if i == 0 {
        CGPathMoveToPoint(ref, nil, p.x, p.y)
    } else {
        CGPathAddLineToPoint(ref, nil, p.x, p.y)
     }
 }

 return ref
 }

this method to draw the pig’s path:

func drawLines() {


//1
  enumerateChildNodesWithName("line", usingBlock: {node, stop in
    node.removeFromParent()
  })

  //2
  enumerateChildNodesWithName("pig", usingBlock: {node, stop in
    //3
    let pig = node as Pig
    if let path = pig.createPathToMove() {          
      let shapeNode = SKShapeNode()
      shapeNode.path = path
      shapeNode.name = "line"
      shapeNode.strokeColor = UIColor.grayColor()
      shapeNode.lineWidth = 2
      shapeNode.zPosition = 1

      self.addChild(shapeNode)
    }
  })
}

And here is your result:

And you can set that path for the pig.

You can modify that as per your need.

Hope it will help.