使用单个SKShapeNode呈现多个重叠的多边形？

Question

我发现，它可能使用单一SKShapeNode对象呈现多个多边形：

class GameScene: SKScene { 

    override func didMove(to view: SKView) { 
     let polygons = [ 
      [ 
       CGPoint(x: 0, y: 0), 
       CGPoint(x: 100, y: 100), 
       CGPoint(x: 100, y: 0) 
      ], 
      [ 
       CGPoint(x: 50, y: 50), 
       CGPoint(x: 50, y: 150), 
       CGPoint(x: 150, y: 150), 
       CGPoint(x: 150, y: 50), 
      ], 
     ] 

     let path = CGMutablePath() 

     for points in polygons { 
      path.addLines(between: points) 
      path.closeSubpath() 
     } 

     let node = SKShapeNode(path: path) 
     node.fillColor = UIColor.red 

     addChild(node) 
    } 
} 

然而，在多边形重叠的任何空间呈现为空：

是否有可能填补那些空白的空间，同时继续使用单个节点？

Answer 1

如果你不关心边界，这里是一个kluge解决方法。

class GameScene: SKScene { 

    override func didMove(to view: SKView) { 
     let polygons = [ 
      [ 
       CGPoint(x: 0, y: 0), 
       CGPoint(x: 100, y: 100), 
       CGPoint(x: 100, y: 0) 
      ], 
      [ 
       CGPoint(x: 50, y: 50), 
       CGPoint(x: 50, y: 150), 
       CGPoint(x: 150, y: 150), 
       CGPoint(x: 150, y: 50), 

      ] 
     ] 

     let path = CGMutablePath() 

     for points in polygons { 
      path.addLines(between: points) 
      path.closeSubpath() 
     } 

     let first = CGMutablePath() 
     first.addLines(between: polygons[0]); 
     first.closeSubpath() 

     let second = CGMutablePath() 
     second.addLines(between: polygons[1]); 
     second.closeSubpath() 

     let node = SKShapeNode(path: first) 
     node.fillColor = .red 
     node.strokeColor = .red 

     let child = SKShapeNode(path: second) 
     child.fillColor = .red 
     child.strokeColor = .red 
     node.addChild(child) 


     addChild(node) 
    } 
} 

如果你关心的边界，然后...

class GameScene: SKScene { 

    override func didMove(to view: SKView) { 
     let polygons = [ 
      [ 
       CGPoint(x: 0, y: 0), 
       CGPoint(x: 100, y: 100), 
       CGPoint(x: 100, y: 0) 
      ], 
      [ 
       CGPoint(x: 50, y: 50), 
       CGPoint(x: 50, y: 150), 
       CGPoint(x: 150, y: 150), 
       CGPoint(x: 150, y: 50), 

      ] 
     ] 

     let path = CGMutablePath() 

     for points in polygons { 
      path.addLines(between: points) 
      path.closeSubpath() 
     } 

     let first = CGMutablePath() 
     first.addLines(between: polygons[0]); 
     first.closeSubpath() 

     let second = CGMutablePath() 
     second.addLines(between: polygons[1]); 
     second.closeSubpath() 

     let node = SKShapeNode(path: first) 
     node.fillColor = .red 
     node.strokeColor = .white 
     node.lineWidth = 2 

     let child = SKShapeNode(path: second) 
     child.fillColor = .red 
     child.strokeColor = .white 
     node.lineWidth = 2 
     node.addChild(child) 

     let child2 = SKShapeNode(path: first) 
     child2.fillColor = .red 
     child2.strokeColor = .clear 
     node.lineWidth = 2 
     node.addChild(child2) 


     addChild(node) 
    } 
}