Collision detection, score counting etc.

Author: iBednar

FlappyBird/GameScene.swift

@@ -8,23 +8,42 @@
 
 import SpriteKit
 
-class GameScene: SKScene {
+class GameScene: SKScene, SKPhysicsContactDelegate{
     let verticalPipeGap = 150.0
-
+    
     var bird:SKSpriteNode!
     var skyColor:SKColor!
     var pipeTextureUp:SKTexture!
     var pipeTextureDown:SKTexture!
     var movePipesAndRemove:SKAction!
-   
+    var moving:SKNode!
+    var pipes:SKNode!
+    var canRestart = Bool()
+    var scoreLabelNode:SKLabelNode!
+    var score = NSInteger()
+    
+    let birdCategory: UInt32 = 1 << 0
+    let worldCategory: UInt32 = 1 << 1
+    let pipeCategory: UInt32 = 1 << 2
+    let scoreCategory: UInt32 = 1 << 3
+    
     override func didMoveToView(view: SKView) {
+        
+        canRestart = false
+        
         // setup physics
         self.physicsWorld.gravity = CGVectorMake( 0.0, -5.0 )
+        self.physicsWorld.contactDelegate = self
 
         // setup background color
         skyColor = SKColor(red: 81.0/255.0, green: 192.0/255.0, blue: 201.0/255.0, alpha: 1.0)
         self.backgroundColor = skyColor
 
+        moving = SKNode()
+        self.addChild(moving)
+        pipes = SKNode()
+        moving.addChild(pipes)
+        
         // ground
         let groundTexture = SKTexture(imageNamed: "land")
         groundTexture.filteringMode = SKTextureFilteringMode.Nearest
@@ -38,7 +57,7 @@ class GameScene: SKScene {
             sprite.setScale(2.0)
             sprite.position = CGPointMake(i * sprite.size.width, sprite.size.height / 2.0)
             sprite.runAction(moveGroundSpritesForever)
-            self.addChild(sprite)
+            moving.addChild(sprite)
         }
 
         // skyline
@@ -55,7 +74,7 @@ class GameScene: SKScene {
             sprite.zPosition = -20
             sprite.position = CGPointMake(i * sprite.size.width, sprite.size.height / 2.0 + groundTexture.size().height * 2.0)
             sprite.runAction(moveSkySpritesForever)
-            self.addChild(sprite)
+            moving.addChild(sprite)
         }
 
         // create the pipes textures
@@ -96,15 +115,27 @@ class GameScene: SKScene {
         bird.physicsBody.dynamic = true
         bird.physicsBody.allowsRotation = false
 
+        bird.physicsBody.categoryBitMask = birdCategory
+        bird.physicsBody.collisionBitMask = worldCategory | pipeCategory
+        bird.physicsBody.contactTestBitMask = worldCategory | pipeCategory
+        
         self.addChild(bird)
 
         // create the ground
         var ground = SKNode()
         ground.position = CGPointMake(0, groundTexture.size().height)
         ground.physicsBody = SKPhysicsBody(rectangleOfSize: CGSizeMake(self.frame.size.width, groundTexture.size().height * 2.0))
         ground.physicsBody.dynamic = false
+        ground.physicsBody.categoryBitMask = worldCategory
         self.addChild(ground)
 
+        // Initialize label and create a label which holds the score
+        score = 0
+        scoreLabelNode = SKLabelNode(fontNamed:"MarkerFelt-Wide")
+        scoreLabelNode.position = CGPointMake( CGRectGetMidX( self.frame ), 3 * self.frame.size.height / 4 )
+        scoreLabelNode.zPosition = 100
+        scoreLabelNode.text = String(score)
+        self.addChild(scoreLabelNode)
 
     }
 
@@ -123,6 +154,8 @@ class GameScene: SKScene {
 
         pipeDown.physicsBody = SKPhysicsBody(rectangleOfSize: pipeDown.size)
         pipeDown.physicsBody.dynamic = false
+        pipeDown.physicsBody.categoryBitMask = pipeCategory
+        pipeDown.physicsBody.contactTestBitMask = birdCategory
         pipePair.addChild(pipeDown)
 
         let pipeUp = SKSpriteNode(texture: pipeTextureUp)
@@ -131,21 +164,57 @@ class GameScene: SKScene {
 
         pipeUp.physicsBody = SKPhysicsBody(rectangleOfSize: pipeUp.size)
         pipeUp.physicsBody.dynamic = false
+        pipeUp.physicsBody.categoryBitMask = pipeCategory
+        pipeUp.physicsBody.contactTestBitMask = birdCategory
         pipePair.addChild(pipeUp)
 
+        var contactNode = SKNode()
+        contactNode.position = CGPointMake( pipeDown.size.width + bird.size.width / 2, CGRectGetMidY( self.frame ) )
+        contactNode.physicsBody = SKPhysicsBody(rectangleOfSize: CGSizeMake( pipeUp.size.width, self.frame.size.height ))
+        contactNode.physicsBody.dynamic = false
+        contactNode.physicsBody.categoryBitMask = scoreCategory
+        contactNode.physicsBody.contactTestBitMask = birdCategory
+        pipePair.addChild(contactNode)
+        
         pipePair.runAction(movePipesAndRemove)
-        self.addChild(pipePair)
+        pipes.addChild(pipePair)
+        
+    }
+    
+    func resetScene (){
+        // Move bird to original position and reset velocity
+        bird.position = CGPointMake(self.frame.size.width / 2.5, CGRectGetMidY(self.frame))
+        bird.physicsBody.velocity = CGVectorMake( 0, 0 )
+        bird.physicsBody.collisionBitMask = worldCategory | pipeCategory
+        bird.speed = 1.0
+        bird.zRotation = 0.0
+        
+        // Remove all existing pipes
+        pipes.removeAllChildren()
+        
+        // Reset _canRestart
+        canRestart = false
+        
+        // Reset score
+        score = 0
+        scoreLabelNode.text = String(score)
+        
+        // Restart animation
+        moving.speed = 1
     }
 
     override func touchesBegan(touches: NSSet, withEvent event: UIEvent) {
         /* Called when a touch begins */
-        
-        for touch: AnyObject in touches {
-            let location = touch.locationInNode(self)
-            
-            bird.physicsBody.velocity = CGVectorMake(0, 0)
-            bird.physicsBody.applyImpulse(CGVectorMake(0, 30))
-            
+        if moving.speed > 0  {
+            for touch: AnyObject in touches {
+                let location = touch.locationInNode(self)
+                
+                bird.physicsBody.velocity = CGVectorMake(0, 0)
+                bird.physicsBody.applyImpulse(CGVectorMake(0, 30))
+                
+            }
+        }else if canRestart {
+            self.resetScene()
         }
     }
 
@@ -165,4 +234,34 @@ class GameScene: SKScene {
         /* Called before each frame is rendered */
         bird.zRotation = self.clamp( -1, max: 0.5, value: bird.physicsBody.velocity.dy * ( bird.physicsBody.velocity.dy < 0 ? 0.003 : 0.001 ) )
     }
+    
+    func didBeginContact(contact: SKPhysicsContact) {
+        if moving.speed > 0 {
+            if ( contact.bodyA.categoryBitMask & scoreCategory ) == scoreCategory || ( contact.bodyB.categoryBitMask & scoreCategory ) == scoreCategory {
+                // Bird has contact with score entity
+                score++
+                scoreLabelNode.text = String(score)
+                
+                // Add a little visual feedback for the score increment
+                scoreLabelNode.runAction(SKAction.sequence([SKAction.scaleTo(1.5, duration:NSTimeInterval(0.1)), SKAction.scaleTo(1.0, duration:NSTimeInterval(0.1))]))
+            } else {
+                
+                moving.speed = 0
+                
+                bird.physicsBody.collisionBitMask = worldCategory
+                bird.runAction(  SKAction.rotateByAngle(CGFloat(M_PI) * CGFloat(bird.position.y) * 0.01, duration:1), completion:{self.bird.speed = 0 })
+                
+                
+                // Flash background if contact is detected
+                self.removeActionForKey("flash")
+                self.runAction(SKAction.sequence([SKAction.repeatAction(SKAction.sequence([SKAction.runBlock({
+                    self.backgroundColor = SKColor(red: 1, green: 0, blue: 0, alpha: 1.0)
+                    }),SKAction.waitForDuration(NSTimeInterval(0.05)), SKAction.runBlock({
+                        self.backgroundColor = self.skyColor
+                        }), SKAction.waitForDuration(NSTimeInterval(0.05))]), count:4), SKAction.runBlock({
+                            self.canRestart = true
+                            })]), withKey: "flash")
+            }
+        }
+    }
 }