var Boot = Container.expand(function () {
	var self = Container.call(this);
	var bootGraphics = self.createAsset('boot', 'Boot', .5, .5);
	self.realWidth = bootGraphics.width * 0.85;
	self.velocityX = 0;
	self.velocityY = 0;
	self.previousX = 0;
	self.previousY = 0;
	self.calculateVelocity = function () {
		self.velocityX = (self.x - self.previousX) / 5;
		self.velocityY = (self.y - self.previousY) / 5;
		self.previousX = self.x;
		self.previousY = self.y;
		var targetRotation = -Math.atan2(self.velocityY, 0) / 2 + Math.PI / 9;
		self.rotation += (targetRotation - self.rotation) * 0.1;
	};
});
var Ball = Container.expand(function () {
	var self = Container.call(this);
	var ballGraphics = self.createAsset('ball', 'Soccer Ball', .5, .5);
	self.velocityX = 0;
	self.velocityY = 0;
	self.gravity = 0.5;
	self.bounceFactor = 0.7;
	self.move = function () {
		self.x += self.velocityX;
		self.y += self.velocityY;
		self.velocityY += self.gravity;
		if (self.x - self.width / 2 < 0) {
			self.velocityX *= -0.7;
			self.x = self.width / 2;
		}
		if (self.x + self.width / 2 > 2048) {
			self.velocityX *= -0.7;
			self.x = 2048 - self.width / 2;
		}
	};
	self.bounce = function (boot) {
		var dx = self.x - boot.x;
		var dy = self.y - boot.y;
		var distance = Math.sqrt(dx * dx + dy * dy);
		var normalX = dx / distance;
		var normalY = dy / distance;
		var dotProduct = -normalX * (boot.velocityX - self.velocityX) - normalY * (boot.velocityY - self.velocityY);
		if (distance < boot.realWidth / 2 + self.width / 2) {
			var overlap = boot.realWidth / 2 + self.width / 2 - distance + 1;
			self.x += overlap * directionX;
			self.y += overlap * directionY;
			var directionX = dx / distance;
			var directionY = dy / distance;
			var relativeVelocityX = self.velocityX - boot.velocityX;
			var relativeVelocityY = self.velocityY - boot.velocityY;
			var speed = relativeVelocityX * directionX + relativeVelocityY * directionY;
			var velocityAlongX = directionX * speed;
			var velocityAlongY = directionY * speed;
			self.velocityX -= 2 * velocityAlongX;
			self.velocityY -= 2 * velocityAlongY;
			self.velocityX += boot.velocityX;
			self.velocityY += boot.velocityY;
			self.velocityX *= self.bounceFactor;
			self.velocityY *= self.bounceFactor;
		}
	};
});
var Game = Container.expand(function () {
	var self = Container.call(this);
	stage.on('move', function (obj) {
		var pos = obj.event.getLocalPosition(self);
		boot.x = pos.x;
		boot.y = pos.y;
	});
	var ball = self.addChild(new Ball());
	ball.x = 2048 / 2;
	ball.y = 2732 / 4;
	var boot = self.addChild(new Boot());
	boot.visible = true;
	var scoreTxt = new Text2('0', {
		size: 150,
		fill: "#ffffff"
	});
	scoreTxt.anchor.set(.5, 0);
	LK.gui.topCenter.addChild(scoreTxt);
	var isGameOver = false;
	var isGameStarted = false;
	stage.on('down', function (obj) {
		var pos = obj.event.getLocalPosition(self);
		boot.x = pos.x;
		boot.y = pos.y;
		boot.visible = true;
	});
	LK.on('tick', function () {
		boot.calculateVelocity();
		if (!isGameStarted) {
			var dx = boot.x - ball.x;
			var dy = boot.y - ball.y;
			var distance = Math.sqrt(dx * dx + dy * dy);
			if (distance < boot.realWidth / 2 + ball.width / 2) {
				ball.bounce(boot);
				isGameStarted = true;
			}
		} else {
			ball.move();
			var dx = boot.x - ball.x;
			var dy = boot.y - ball.y;
			var distance = Math.sqrt(dx * dx + dy * dy);
			if (distance < boot.realWidth / 2 + ball.width / 2) {
				ball.bounce(boot);
			}
		}
		if (ball.y > 2732 - ball.height / 2) {
			isGameOver = true;
		}
		if (isGameOver) {
			LK.effects.flashScreen(0xff0000, 1000);
			LK.showGameOver();
		}
	});
});

===================================================================
--- original.js
+++ change.js
@@ -42,8 +42,11 @@
 		var normalX = dx / distance;
 		var normalY = dy / distance;
 		var dotProduct = -normalX * (boot.velocityX - self.velocityX) - normalY * (boot.velocityY - self.velocityY);
 		if (distance < boot.realWidth / 2 + self.width / 2) {
+			var overlap = boot.realWidth / 2 + self.width / 2 - distance + 1;
+			self.x += overlap * directionX;
+			self.y += overlap * directionY;
 			var directionX = dx / distance;
 			var directionY = dy / distance;
 			var relativeVelocityX = self.velocityX - boot.velocityX;
 			var relativeVelocityY = self.velocityY - boot.velocityY;
@@ -55,11 +58,8 @@
 			self.velocityX += boot.velocityX;
 			self.velocityY += boot.velocityY;
 			self.velocityX *= self.bounceFactor;
 			self.velocityY *= self.bounceFactor;
-			var overlap = boot.realWidth / 2 + self.width / 2 - distance + 1;
-			self.x += overlap * directionX;
-			self.y += overlap * directionY;
 		}
 	};
 });
 var Game = Container.expand(function () {