/**** 
* Classes
****/
// Hero class
var Hero = Container.expand(function () {
	var self = Container.call(this);
	var heroGraphics = self.createAsset('hero', 'Hero character', 0.5, 0.5);
	self.speed = 9;
	self.jumpPower = -18;
	self.gravity = 0.5;
	self.isJumping = false;
	self.velocityY = 0;
	self.update = function () {
		// Apply gravity
		if (self.isJumping || self.isFalling) {
			self.velocityY += self.gravity;
			self.y += self.velocityY;
			if (self.y > game.height - heroGraphics.height / 2) {
				self.isJumping = false;
				self.isFalling = false;
				self.jumpCount = 0;
				self.y = game.height - heroGraphics.height / 2;
			}
		}
		self.isFalling = false;
	};
	self.jumpCount = 0;
	self.maxJumps = 2;
	self.isFalling = false;
	self.jump = function () {
		if (self.jumpCount < self.maxJumps) {
			self.jumpCount++;
			self.isJumping = true;
			self.velocityY = self.jumpPower;
		}
	};
	self.fallQuickly = function () {
		self.isFalling = true;
		self.velocityY = self.gravity * 50;
	};
});
// Obstacle class
var Obstacle = Container.expand(function () {
	var self = Container.call(this);
	var obstacleGraphics = self.createAsset('obstacle', 'Obstacle', 0.5, 1);
	self.speed = -10;
	self.move = function () {
		self.x += self.speed;
	};
});
// Bullet class
var Bullet = Container.expand(function () {
	var self = Container.call(this);
	var bulletGraphics = self.createAsset('bullet', 'Hero Bullet', 0.5, 0.5);
	self.speed = 15;
	self.move = function () {
		self.x += self.speed;
	};
	self.checkCollisionWithObstacles = function (obstacles) {
		for (var i = obstacles.length - 1; i >= 0; i--) {
			if (self.intersects(obstacles[i])) {
				obstacles[i].destroy();
				obstacles.splice(i, 1);
				self.destroy();
				return true;
			}
		}
		return false;
	};
});

/**** 
* Initialize Game
****/
var game = new LK.Game({
	backgroundColor: 0x000000 // Init game with black background
});

/**** 
* Game Code
****/
// Initialize hero
var hero = game.addChild(new Hero());
hero.x = game.width / 4;
hero.y = game.height - hero.height / 2;

// Initialize obstacles array
var obstacles = [];

// Initialize score
var score = 0;
var scoreTxt = new Text2(score.toString(), {
	size: 150,
	fill: "#ffffff"
});
scoreTxt.anchor.set(0.5, 0);
LK.gui.top.addChild(scoreTxt);

// Game tick event
LK.on('tick', function () {
	// Update hero
	hero.update();

	// Move and check obstacles
	for (var i = obstacles.length - 1; i >= 0; i--) {
		obstacles[i].move();
		// Check for collision with hero
		if (hero.intersects(obstacles[i])) {
			// Check if hero jumps on top of the obstacle
			if (hero.y + hero.height / 2 <= obstacles[i].y - obstacles[i].height / 2 && hero.velocityY > 0) {
				// Remove the obstacle if jumped on top
				obstacles[i].destroy();
				obstacles.splice(i, 1);
			} else {
				// Game over if collided from the side
				LK.effects.flashScreen(0xff0000, 1000);
				LK.showGameOver();
				return;
			}
		}
		// Remove off-screen obstacles
		if (obstacles[i].x < -obstacles[i].width) {
			obstacles[i].destroy();
			obstacles.splice(i, 1);
		}
	}

	// Increment score
	score++;
	scoreTxt.setText(score.toString());

	// Move and check bullets
	for (var b = bullets.length - 1; b >= 0; b--) {
		bullets[b].move();
		if (bullets[b].checkCollisionWithObstacles(obstacles)) {
			bullets.splice(b, 1);
		} else if (bullets[b].x > game.width) {
			bullets[b].destroy();
			bullets.splice(b, 1);
		}
	}
	// Add new obstacles
	if (LK.ticks % 100 == 0) {
		var obstacle = new Obstacle();
		obstacle.x = game.width;
		obstacle.y = game.height;
		obstacles.push(obstacle);
		game.addChild(obstacle);
	}
});

// Prepare for swipe detection
var swipeStart = null;
var swipeThreshold = 50; // Minimum distance for a swipe to count

// Touch start event to record the start position of a swipe
game.on('down', function (obj) {
	var event = obj.event;
	swipeStart = event.getLocalPosition(game);
});

// Touch end event to detect a swipe
game.on('up', function (obj) {
	var event = obj.event;
	var swipeEnd = event.getLocalPosition(game);
	if (swipeStart) {
		if (Math.abs(swipeEnd.y - swipeStart.y) > swipeThreshold) {
			if (swipeStart.y > swipeEnd.y) {
				hero.jump();
			} else if (swipeStart.y < swipeEnd.y) {
				hero.fallQuickly();
			}
		}
	} else {
		// Shoot a bullet when the player taps
		var bullet = new Bullet();
		bullet.x = hero.x + hero.width / 2;
		bullet.y = hero.y;
		bullets.push(bullet);
		game.addChild(bullet);
	}
	swipeStart = null; // Reset swipe start position
});

===================================================================
--- original.js
+++ change.js
@@ -47,16 +47,27 @@
 	self.move = function () {
 		self.x += self.speed;
 	};
 });
-// Platform class
-var Platform = Container.expand(function () {
+// Bullet class
+var Bullet = Container.expand(function () {
 	var self = Container.call(this);
-	var platformGraphics = self.createAsset('platform', 'Platform', 0.5, 1);
-	self.speed = -10;
+	var bulletGraphics = self.createAsset('bullet', 'Hero Bullet', 0.5, 0.5);
+	self.speed = 15;
 	self.move = function () {
 		self.x += self.speed;
 	};
+	self.checkCollisionWithObstacles = function (obstacles) {
+		for (var i = obstacles.length - 1; i >= 0; i--) {
+			if (self.intersects(obstacles[i])) {
+				obstacles[i].destroy();
+				obstacles.splice(i, 1);
+				self.destroy();
+				return true;
+			}
+		}
+		return false;
+	};
 });
 
 /**** 
 * Initialize Game
@@ -94,18 +105,15 @@
 	for (var i = obstacles.length - 1; i >= 0; i--) {
 		obstacles[i].move();
 		// Check for collision with hero
 		if (hero.intersects(obstacles[i])) {
-			// Check if hero lands on top of the platform
-			if (hero.y + hero.height / 2 <= obstacles[i].y && hero.velocityY > 0) {
-				// Land the hero on the platform
-				hero.isJumping = false;
-				hero.isFalling = false;
-				hero.jumpCount = 0;
-				hero.y = obstacles[i].y - hero.height / 2;
-				hero.velocityY = 0;
-			} else if (hero.x + hero.width / 2 > obstacles[i].x && hero.velocityY >= 0) {
-				// Game over if collided from the side while falling or not jumping
+			// Check if hero jumps on top of the obstacle
+			if (hero.y + hero.height / 2 <= obstacles[i].y - obstacles[i].height / 2 && hero.velocityY > 0) {
+				// Remove the obstacle if jumped on top
+				obstacles[i].destroy();
+				obstacles.splice(i, 1);
+			} else {
+				// Game over if collided from the side
 				LK.effects.flashScreen(0xff0000, 1000);
 				LK.showGameOver();
 				return;
 			}
@@ -120,15 +128,25 @@
 	// Increment score
 	score++;
 	scoreTxt.setText(score.toString());
 
+	// Move and check bullets
+	for (var b = bullets.length - 1; b >= 0; b--) {
+		bullets[b].move();
+		if (bullets[b].checkCollisionWithObstacles(obstacles)) {
+			bullets.splice(b, 1);
+		} else if (bullets[b].x > game.width) {
+			bullets[b].destroy();
+			bullets.splice(b, 1);
+		}
+	}
 	// Add new obstacles
 	if (LK.ticks % 100 == 0) {
-		var platform = new Platform();
-		platform.x = game.width;
-		platform.y = game.height - platform.height / 2;
-		obstacles.push(platform);
-		game.addChild(platform);
+		var obstacle = new Obstacle();
+		obstacle.x = game.width;
+		obstacle.y = game.height;
+		obstacles.push(obstacle);
+		game.addChild(obstacle);
 	}
 });
 
 // Prepare for swipe detection
@@ -152,7 +170,14 @@
 			} else if (swipeStart.y < swipeEnd.y) {
 				hero.fallQuickly();
 			}
 		}
+	} else {
+		// Shoot a bullet when the player taps
+		var bullet = new Bullet();
+		bullet.x = hero.x + hero.width / 2;
+		bullet.y = hero.y;
+		bullets.push(bullet);
+		game.addChild(bullet);
 	}
 	swipeStart = null; // Reset swipe start position
 });
\ No newline at end of file