 import MultipeerConnectivity
 
 struct PhysicsCategory {
-    static let None      : UInt32 = 0
-    static let All       : UInt32 = UInt32.max
-    static let RightSquirrel: UInt32 = 0b10
-    static let LeftSquirrel: UInt32 = 0b1
-    static let LeftBomb: UInt32 = 0b11
-    static let RightBomb: UInt32 = 0b100
-
+    //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
+    static let RightBomb        : UInt32 = 0x1 << 3
+    static let Environment      : UInt32 = 0x1 << 4
 }
 
 class GameScene: SKScene, SKPhysicsContactDelegate {

        
        bomb.physicsBody = SKPhysicsBody(rectangleOf: bomb.size)
        bomb.physicsBody?.categoryBitMask = bombCategory
        bomb.physicsBody?.contactTestBitMask = PhysicsCategory.All
        bomb.physicsBody?.collisionBitMask = physicsCategory

        
        addChild(bomb)

        rightSquirrel.anchorPoint.y = 0.5
        rightSquirrel.zPosition = 1
        rightSquirrel.physicsBody = SKPhysicsBody(rectangleOf: rightSquirrel.size)
        //rightSquirrel.physicsBody?.isDynamic = false
        rightSquirrel.physicsBody?.categoryBitMask = PhysicsCategory.RightSquirrel
        addChild(rightSquirrel)
        
