/**** 
* Plugins
****/ 
var tween = LK.import("@upit/tween.v1");

/**** 
* Classes
****/ 
// AimBar class (player's horizontal aim)
var AimBar = Container.expand(function () {
	var self = Container.call(this);
	var aimGfx = self.attachAsset('gun', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.gfx = aimGfx;
	return self;
});
// Tile class (falling note)
var Tile = Container.expand(function () {
	var self = Container.call(this);
	var tileGfx = self.attachAsset('tile', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.gfx = tileGfx;
	self.speed = 0; // Set per tile
	self.hit = false;
	self.update = function () {
		if (self.hit) return;
		self.y += self.speed;
	};
	// Flash tile when hit with explosion effect
	self.flashHit = function () {
		self.hit = true;
		// Store original values
		var origScaleX = self.gfx.scaleX || 1;
		var origScaleY = self.gfx.scaleY || 1;
		var origRotation = self.gfx.rotation || 0;
		// Explosion effect: scale up and rotate while changing color
		tween(self.gfx, {
			tint: 0xffe100,
			scaleX: origScaleX * 1.5,
			scaleY: origScaleY * 1.5,
			rotation: origRotation + Math.PI * 0.25
		}, {
			duration: 80,
			onFinish: function onFinish() {
				// Scale back down and continue rotation while changing to final color
				tween(self.gfx, {
					tint: 0x00eaff,
					scaleX: origScaleX * 0.8,
					scaleY: origScaleY * 0.8,
					rotation: origRotation + Math.PI * 0.5,
					alpha: 0.7
				}, {
					duration: 120
				});
			}
		});
	};
	return self;
});

/**** 
* Initialize Game
****/ 
var game = new LK.Game({
	backgroundColor: 0x0a0a1a
});

/**** 
* Game Code
****/ 
// --- Tiles now fall in sync with the music rhythm (BPM-based pattern) ---
// --- Add background image ---
var bg = LK.getAsset('bgimg', {
	anchorX: 0.5,
	anchorY: 0.5,
	scaleX: GAME_W / 2048,
	scaleY: GAME_H / 2732,
	x: GAME_W / 2,
	y: GAME_H / 2
});
game.addChild(bg);
// --- Game constants ---
// Tiles (falling notes)
// Gun (player's shooter)
// Bullet
// Sound: gunfire
// Sound: tile hit
// Music: EDM track (looping)
var GAME_W = 2048,
	GAME_H = 2732;
var GUN_Y = GAME_H - 320;
var TILE_ROWS = 4; // Number of tile lanes
var TILE_LANE_W = GAME_W / TILE_ROWS;
var TILE_SPAWN_Y = -60;
var TILE_TARGET_Y = GAME_H - 520; // Where tiles should be hit
var TILE_SPEED = 22; // px per frame (tuned for rhythm)
var TILE_INTERVAL = 32; // frames between tiles (tuned for rhythm)
var BULLET_SPEED = -60;
var BULLET_FIRE_INTERVAL = 6; // frames between bullets when holding
var HIT_WINDOW = 90; // px vertical window for hit
var GUN_MOVE_LIMIT = 180; // px from screen edge
// --- Game state ---
var aimBar;
var tiles = [];
var score = 0;
var dragAim = false;
var dragOffsetX = 0;
var tickCount = 0;
var nextTileTick = 0;
var tilePattern = []; // Array of {lane, tick}
var patternIndex = 0;
var gameOver = false;
// --- UI ---
var scoreTxt = new Text2('0', {
	size: 120,
	fill: 0xFFFFFF
});
scoreTxt.anchor.set(0.5, 0);
LK.gui.top.addChild(scoreTxt);
// --- Music ---
LK.playMusic('edm1');
// --- Helper: Generate a rhythm pattern based on music BPM ---
function generatePattern() {
	// Example: EDM1 is 128 BPM, so 128 beats per 60 seconds = 2.133 beats/sec
	// 60 FPS, so 1 beat = ~28 frames
	var BPM = 128;
	var BEATS = 64; // Number of beats/tiles
	var FRAMES_PER_BEAT = Math.round(60 * 60 / BPM); // 60 seconds * 60 FPS / BPM
	tilePattern = [];
	// Add 1.5 second delay (90 frames at 60fps) before first tile
	var t = 90;
	// Example rhythm: every beat, random lane, but you can use a fixed pattern for more musicality
	for (var i = 0; i < BEATS; i++) {
		var lane = Math.floor(Math.random() * TILE_ROWS);
		tilePattern.push({
			lane: lane,
			tick: t
		});
		t += FRAMES_PER_BEAT;
	}
}
// --- Helper: Spawn a tile at a given lane ---
function spawnTile(lane, speedup) {
	var tile = new Tile();
	// All tiles spawn at the horizontal center of the screen
	tile.x = GAME_W / 2;
	tile.y = TILE_SPAWN_Y;
	// Calculate speed so tile reaches the hit line exactly on the beat
	// Find the next pattern entry for this lane
	// We'll use the default: time from spawn to hit = FRAMES_TO_HIT
	var FRAMES_TO_HIT = 60; // 1 second to reach hit line (tune as needed)
	var distance = TILE_TARGET_Y - TILE_SPAWN_Y;
	tile.speed = distance / FRAMES_TO_HIT * (speedup || 1);
	tile.lane = lane;
	tile.hit = false;
	tiles.push(tile);
	game.addChild(tile);
}
// --- Helper: Fire a bullet from gun towards a lane ---
function fireBullet() {
	var barrel = gun.getBarrel();
	var bullet = new Bullet();
	bullet.x = barrel.x;
	bullet.y = barrel.y;
	bullet.speed = BULLET_SPEED;
	bullets.push(bullet);
	game.addChild(bullet);
	LK.getSound('gunfire').play();
}
// --- Helper: Check if bullet hits a tile ---
function checkBulletTileCollision(bullet, tile) {
	// Only check if tile not hit
	if (tile.hit) return false;
	// Check if bullet and tile are in same lane (x overlap)
	var dx = Math.abs(bullet.x - tile.x);
	if (dx > TILE_LANE_W / 2 - 30) return false;
	// Check if bullet is within hit window (y)
	var dy = Math.abs(bullet.y - tile.y);
	if (dy < HIT_WINDOW) return true;
	return false;
}
// --- Helper: End game ---
function endGame() {
	if (gameOver) return;
	gameOver = true;
	LK.effects.flashScreen(0xff0033, 800);
	LK.showGameOver();
}
// --- Helper: Win game ---
function winGame() {
	if (gameOver) return;
	gameOver = true;
	LK.effects.flashScreen(0x00ff99, 800);
	LK.showYouWin();
}
// --- Initialize game objects ---
function resetGame() {
	// Remove all tiles
	for (var i = 0; i < tiles.length; i++) tiles[i].destroy();
	tiles = [];
	score = 0;
	scoreTxt.setText('0');
	tickCount = 0;
	nextTileTick = 0;
	patternIndex = 0;
	gameOver = false;
	dragAim = false;
	// AimBar
	if (aimBar) aimBar.destroy();
	aimBar = new AimBar();
	aimBar.x = GAME_W / 2;
	// Move the gun a bit higher (e.g. 200px higher than before)
	aimBar.y = GUN_Y - 200;
	game.addChild(aimBar);
	// Pattern
	generatePattern();
}
resetGame();
// --- Input: Drag to move aim bar horizontally ---
game.down = function (x, y, obj) {
	// Only allow drag if touch is on aim bar or below
	if (y >= aimBar.y - aimBar.gfx.height / 2 - 60) {
		dragAim = true;
		dragOffsetX = x - aimBar.x;
	}
};
game.move = function (x, y, obj) {
	if (dragAim) {
		// Clamp aim bar movement to screen
		var nx = x - dragOffsetX;
		nx = Math.max(GUN_MOVE_LIMIT, Math.min(GAME_W - GUN_MOVE_LIMIT, nx));
		aimBar.x = nx;
	}
};
game.up = function (x, y, obj) {
	dragAim = false;
};
// --- Main game loop ---
game.update = function () {
	if (gameOver) return;
	tickCount++;
	// --- Accelerate tile speed over time ---
	var speedup = 1 + Math.min(1.5, tickCount / 1200); // up to 2.5x speed after ~20 seconds
	// --- Spawn tiles according to pattern ---
	while (patternIndex < tilePattern.length && tilePattern[patternIndex].tick <= tickCount) {
		spawnTile(tilePattern[patternIndex].lane, speedup);
		patternIndex++;
	}
	// --- Move tiles and check for hits ---
	for (var i = tiles.length - 1; i >= 0; i--) {
		var tile = tiles[i];
		tile.update();
		// Missed tile? (passed target line)
		if (!tile.hit && tile.y > TILE_TARGET_Y + HIT_WINDOW) {
			endGame();
			return;
		}
		// Remove tile if off screen
		if (tile.y > GAME_H + 100) {
			tile.destroy();
			tiles.splice(i, 1);
			continue;
		}
		// Check for hit: if tile is within hit window and aimBar is aligned horizontally
		if (!tile.hit && Math.abs(tile.y - TILE_TARGET_Y) < HIT_WINDOW) {
			var dx = Math.abs(tile.x - aimBar.x);
			if (dx < TILE_LANE_W / 2 - 30) {
				tile.flashHit();
				score += 10;
				scoreTxt.setText(score);
				// --- Rotate aimBar randomly left or right 90deg and return to original ---
				var origRot = aimBar.gfx.rotation || 0;
				var origScaleX = aimBar.gfx.scaleX || 1;
				var origScaleY = aimBar.gfx.scaleY || 1;
				var dir = Math.random() < 0.5 ? -1 : 1;
				tween(aimBar.gfx, {
					rotation: origRot + dir * (Math.PI / 2),
					scaleX: origScaleX * 1.1,
					scaleY: origScaleY * 1.1
				}, {
					duration: 120,
					onFinish: function onFinish() {
						tween(aimBar.gfx, {
							rotation: origRot,
							scaleX: origScaleX,
							scaleY: origScaleY
						}, {
							duration: 120
						});
					}
				});
				// Remove tile after short delay
				(function (tileObj) {
					LK.setTimeout(function () {
						tileObj.destroy();
						var idx = tiles.indexOf(tileObj);
						if (idx !== -1) tiles.splice(idx, 1);
					}, 80);
				})(tile);
				// Endless: No win condition
			}
		}
	}
};
// --- Reset game on game over/win ---
LK.on('gameover', function () {
	resetGame();
});
LK.on('youwin', function () {
	resetGame();
});

===================================================================
--- original.js
+++ change.js
@@ -145,12 +145,10 @@
 }
 // --- Helper: Spawn a tile at a given lane ---
 function spawnTile(lane, speedup) {
 	var tile = new Tile();
-	// Clamp tile X so it never gets close to the left/right edge (wider margin)
-	var TILE_EDGE_MARGIN = 220;
-	var idealX = TILE_LANE_W * (lane + 0.5);
-	tile.x = Math.max(TILE_EDGE_MARGIN, Math.min(GAME_W - TILE_EDGE_MARGIN, idealX));
+	// All tiles spawn at the horizontal center of the screen
+	tile.x = GAME_W / 2;
 	tile.y = TILE_SPAWN_Y;
 	// Calculate speed so tile reaches the hit line exactly on the beat
 	// Find the next pattern entry for this lane
 	// We'll use the default: time from spawn to hit = FRAMES_TO_HIT