Untitled

<html>

<canvas id="gameCanvas" width="800" height="600"></canvas>

<script>
var canvas;
var canvasContext;
var ballX = 50;
var ballY = 50;
var ballSpeedX= 10;
var ballSpeedY= 10;

var player1Score = 0;
var player2Score = 0;
const WINNING_SCORE = 5;

var showingWinScreen = false;

var paddle1Y = 250;
var paddle2Y = 250;
const PADDLE_THICKNESS = 10;
const PADDLE_HEIGHT = 100;


function calculateMousePos(evt) {
	var rect = canvas.getBoundingClientRect();
	var root = document.documentElement;
	var MouseX = evt.clientX - rect.left - root.scrollLeft;
	var MouseY = evt.clientY - rect.top - root.scrollTop;
	return {
		x:MouseX,
		y:MouseY
	};
}
function handleMouseClick(evt) {
	if (showingWinScreen) {
		showingWinScreen = false;
		player1Score = 0;
		player2Score = 0;
	}
}
window.onload = function() {
	canvas = document. getElementById('gameCanvas');
	canvasContext = canvas.getContext('2d');

	var framesPerSecond = 30;
	setInterval(function () {
		moveEverything();
		drawEverything();
	 }, 1000/framesPerSecond );

	canvas.addEventListener('mousedown',handleMouseClick);

	canvas.addEventListener('mousemove',
		function(evt) {
			var mousePos = calculateMousePos(evt);
			paddle1Y = mousePos.y-(PADDLE_HEIGHT/2);
		});
}

function ballReset() {
	if(player1Score >= WINNING_SCORE ||
	   player2Score >= WINNING_SCORE) {
			player1Score= 0;
			player2Score= 0;
	}

	ballSpeedX = -ballSpeedX;
	ballX = canvas.width/2;
	ballY = canvas.height/2;

}

function computerMovement() {
	var paddle2YCenter = paddle2Y + (PADDLE_HEIGHT/2);
	if(paddle2YCenter < ballY-25) {
		paddle2Y += 6;
	} else if(paddle2YCenter > ballY+25) {
		paddle2Y -= 6;
	}
}

function moveEverything() {
	if(showingWinScreen)  {
		return;
	}
	computerMovement();

	ballX += ballSpeedX;
	ballY += ballSpeedY;
	if(ballX < 0) {
		if(ballY > paddle1Y &&
		  ballY < paddle1Y+PADDLE_HEIGHT) {
			ballSpeedX = -ballSpeedX;

			var dektaY = ballY
				-(paddle1Y+PADDLE_HEIGHT/2);
			ballSpeedY = deltaY * 0.35;
		} else {
			player2Score++; //must be BEFORE ballReset()
			ballReset();
			showingWinScreen = true;
		}
	}
	if(ballX > canvas.width) {
		if(ballY > paddle2Y &&
		  ballY < paddle2Y+PADDLE_HEIGHT) {
			ballSpeedX = -ballSpeedX;

			var dektaY = ballY
				-(paddle2Y+PADDLE_HEIGHT/2);
			ballSpeedY = deltaY * 0.35;
		} else {
			player1Score++; //must be BEFORE ballReset()
			ballReset();
			showingWinScreen = true;
		}
	}
	if(ballY < 0) {
		ballSpeedY = -ballSpeedY;
	}
	if(ballY > canvas.height) {
		ballSpeedY = -ballSpeedY;
	}
}

function drawEverything() {


	// next line blanks out the screen with black
	colorRect (0,0,canvas.width,canvas.height,'black');

	if(showingWinScreen)  {
	canvasContext.fillStyle = 'white';
	canvasContext.fillText ("click to continue", 100, 100);
		return;
	}

	// this is left player paddle
	colorRect (0, paddle1Y, PADDLE_THICKNESS, PADDLE_HEIGHT,'white');

	// this is right computer paddle
	colorRect (canvas.width-PADDLE_THICKNESS, paddle2Y, PADDLE_THICKNESS, PADDLE_HEIGHT,'white');

	//next line draws the ball
	colorCircle(ballX, ballY, 10, 'white');

	canvasContext.fillText (player1Score, 100, 100);
	canvasContext.fillText (player2Score, canvas.width-100,100);
}

function colorCircle(centerX, centerY, radius, drawColor) {
	canvasContext.fillStyle = 'drawColor';
	canvasContext.beginPath();
	canvasContext.arc(centerX, centerY, radius, 0,Math.PI*2, true);
	canvasContext.fill();
}

function colorRect(leftX,topY, width,height, drawColor) {
	canvasContext.fillStyle = drawColor;
	canvasContext.fillRect(leftX,topY,width,height);
}


</script>

</html>