Gamedev Canvas Workshop - lesson 2

Move the ball.

by TR1N1TYF0XX

HTML

<canvas id="myCanvas" width="480" height="320"></canvas>

CSS

canvas { background: #eee; }

JavaScript

var canvas = document.getElementById("myCanvas");
var ctx = canvas.getContext("2d");
var x = canvas.width/2;
var y = canvas.height-30;
var dx = -20;
var dy = -20;

function drawBall() {
    ctx.beginPath();
    ctx.arc(x, y, 20, 0, Math.PI*2);
    ctx.fillStyle = "black";
    ctx.fill();
    ctx.closePath();
}

function draw() {
    ctx.clearRect(0, 0, canvas.width, canvas.height);
    drawBall();
    x += dx;
    y += dy;
}

setInterval(draw, 30);