/**** 
* Classes
****/ 
var Background = Container.expand(function () {
	var self = Container.call(this);
	var bg1 = self.attachAsset('background', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	var bg2 = self.attachAsset('background', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	bg1.y = 0;
	bg2.y = -2732;
	self.update = function () {
		bg1.y += 2;
		bg2.y += 2;
		// Update background
		background.update();
		//Always call move and tick methods from the main tick method in the 'Game' class.
		if (bg1.y >= 2732) {
			bg1.y = bg2.y - 2732;
		}
		if (bg2.y >= 2732) {
			bg2.y = bg1.y - 2732;
		}
	};
});
// Diver class
var Diver = Container.expand(function () {
	var self = Container.call(this);
	var diverGraphics = self.attachAsset('diver', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	// Add a sideways movement to the diver
	self.movement = 0;
	self.direction = 1;
	self.update = function () {
		self.movement += self.direction * 0.03;
		if (self.movement > 0.5 || self.movement < -0.5) {
			self.direction *= -1;
		}
		self.x += self.movement;
	};
	// Add flippers to the diver
	var leftFlipper = self.addChild(new Flipper());
	leftFlipper.x = -50;
	leftFlipper.depth = -1;
	var rightFlipper = self.addChild(new Flipper());
	rightFlipper.x = 50;
	rightFlipper.depth = -1;
});
// Flipper class
var Flipper = Container.expand(function () {
	var self = Container.call(this);
	var flipperGraphics = self.attachAsset('flippers', {
		anchorX: 0.5,
		anchorY: 1.0
	});
	// Set flipper movement
	self.movement = 0;
	self.direction = 1;
	// This is automatically called every game tick, if the flipper is attached!
	self.update = function () {
		// Move the flipper subtly to simulate flipping
		self.movement += self.direction * 0.03;
		if (self.movement > 0.5 || self.movement < -0.5) {
			self.direction *= -1;
		}
		self.rotation = self.movement;
	};
});
// Obstacle1 class
var Obstacle1 = Container.expand(function () {
	var self = Container.call(this);
	var obstacle1Graphics = self.attachAsset('obstacle1', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	// Set obstacle1 speed
	self.speed = -5;
	// This is automatically called every game tick, if the obstacle1 is attached!
	self.update = function () {
		// Check if the obstacle is colliding with the shield
		if (self.intersects(shield)) {
			// Push the obstacle to the right if the shield is on its left
			if (self.x < shield.x) {
				self.x -= 5;
				// Prevent shield from overlapping with obstacle
				if (self.intersects(shield)) {
					self.x -= 5;
				}
			}
			// Push the obstacle to the left if the shield is on its right
			else if (self.x > shield.x) {
				self.x += 5;
				// Prevent shield from overlapping with obstacle
				if (self.intersects(shield)) {
					self.x += 5;
				}
			}
		}
		// Check for collision with diver
		if (self.intersects(diver)) {
			// Flash screen red for 1 second (1000ms) to show game over
			LK.effects.flashScreen(0xff0000, 1000);
			// Show game over. The game will be automatically paused while game over is showing.
			LK.showGameOver();
		}
		// Continue moving upwards
		self.y += self.speed;
		if (self.y < 0) {
			self.y = 2732;
		}
		// Check if the obstacle is colliding with another obstacle
		for (var i = 0; i < obstacles.length; i++) {
			var otherObstacle = obstacles[i];
			if (self !== otherObstacle && self.intersects(otherObstacle)) {
				// Push the obstacle to the right if the other obstacle is on its left
				if (self.x < otherObstacle.x) {
					self.x -= 5;
					// Prevent obstacle from overlapping with other obstacle
					if (self.intersects(otherObstacle)) {
						self.x -= 5;
					}
				}
				// Push the obstacle to the left if the other obstacle is on its right
				else if (self.x > otherObstacle.x) {
					self.x += 5;
					// Prevent obstacle from overlapping with other obstacle
					if (self.intersects(otherObstacle)) {
						self.x += 5;
					}
				}
			}
		}
	};
});
// Shield class
var Shield = Container.expand(function () {
	var self = Container.call(this);
	var shieldGraphics = self.attachAsset('shield', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.down = function (x, y, obj) {
		dragNode = self;
	};
});

/**** 
* Initialize Game
****/ 
// Create a diver instance
//<Assets used in the game will automatically appear here>
var game = new LK.Game({
	backgroundColor: 0xADD8E6 //Init game with light blue background
});

/**** 
* Game Code
****/ 
// Create background instance
var background = game.addChild(new Background());
// Create a shield instance
var shield = game.addChild(new Shield());
// Position the shield at the center of the screen
shield.x = 2048 / 2;
shield.y = 2732 / 2;
// Create a diver instance
var dragNode = null;
var diver = new Diver();
diver.depth = 2;
// Position the diver at the top center of the screen, 200 pixels down from the top
diver.x = 2048 / 2;
diver.y = 500;
// Position the flippers relative to the diver
diver.children[0].y = diver.height / 2 - 20; // Left flipper
diver.children[0].y = diver.children[0].y; // Right flipper
// Set diver to a higher depth than flippers
diver.depth = 2;
// Create an obstacle1 instance
game.move = function (x, y, obj) {
	if (dragNode) {
		dragNode.x = x;
		dragNode.y = y;
	}
};
var obstacles = [];
var obstacle1 = new Obstacle1();
game.addChild(diver);
game.setChildIndex(diver, game.children.length - 1);
game.addChild(obstacle1);
// Position the obstacle1 at the bottom center of the screen
obstacle1.x = 2048 / 2 - 100;
obstacle1.y = 2732;
obstacles.push(obstacle1);
var obstacle2 = game.addChild(new Obstacle1());
// Position the obstacle2 next to obstacle1
obstacle2.x = 2048 / 2 + 100;
obstacle2.y = 2732;
obstacles.push(obstacle2);
;
game.up = function (x, y, obj) {
	dragNode = null;
};

===================================================================
--- original.js
+++ change.js
@@ -1,7 +1,33 @@
 /**** 
 * Classes
 ****/ 
+var Background = Container.expand(function () {
+	var self = Container.call(this);
+	var bg1 = self.attachAsset('background', {
+		anchorX: 0.5,
+		anchorY: 0.5
+	});
+	var bg2 = self.attachAsset('background', {
+		anchorX: 0.5,
+		anchorY: 0.5
+	});
+	bg1.y = 0;
+	bg2.y = -2732;
+	self.update = function () {
+		bg1.y += 2;
+		bg2.y += 2;
+		// Update background
+		background.update();
+		//Always call move and tick methods from the main tick method in the 'Game' class.
+		if (bg1.y >= 2732) {
+			bg1.y = bg2.y - 2732;
+		}
+		if (bg2.y >= 2732) {
+			bg2.y = bg1.y - 2732;
+		}
+	};
+});
 // Diver class
 var Diver = Container.expand(function () {
 	var self = Container.call(this);
 	var diverGraphics = self.attachAsset('diver', {
@@ -135,8 +161,10 @@
 
 /**** 
 * Game Code
 ****/ 
+// Create background instance
+var background = game.addChild(new Background());
 // Create a shield instance
 var shield = game.addChild(new Shield());
 // Position the shield at the center of the screen
 shield.x = 2048 / 2;