 import MultipeerConnectivity
 
 struct PhysicsCategory {
-    //static let None      : UInt32 = 0
-    //static let All       : UInt32 = UInt32.max
+    static let None             : UInt32 = 0
+    static let All              : UInt32 = UInt32.max
     static let RightSquirrel    : UInt32 = 0x1 << 0
     static let LeftSquirrel     : UInt32 = 0x1 << 1
     static let LeftBomb         : UInt32 = 0x1 << 2

        //rightSquirrel.physicsBody?.isDynamic = false
        rightSquirrel.physicsBody?.categoryBitMask = PhysicsCategory.RightSquirrel
        rightSquirrel.physicsBody?.contactTestBitMask = PhysicsCategory.LeftBomb
        addChild(rightSquirrel)
        
        middleTree.position = CGPoint(x: 0, y: -4.238)

        middleTree.physicsBody = SKPhysicsBody(rectangleOf: middleTree.size)
        middleTree.physicsBody?.categoryBitMask = PhysicsCategory.Environment
        middleTree.physicsBody?.contactTestBitMask = PhysicsCategory.LeftBomb | PhysicsCategory.RightBomb
        middleTree.physicsBody?.collisionBitMask = PhysicsCategory.None
        middleTree.physicsBody?.affectedByGravity = false
        addChild(middleTree)
        
        leftTree.position = CGPoint(x: -147.94, y: -62.205)
