<html>
<head>
<script type="text/javascript">
player_pos = 0;
pewpew = 0;
document.onkeydown = onKeyDown;
function onKeyDown(e) {
e = e || window.event;
var player = document.getElementById("player");
if (e.keyCode == '37') { // left
player_pos -= 10;
player.style.left = player_pos;
}
if (e.keyCode == '39') { // right
player_pos += 10;
player.style.left = player_pos;
}
if (e.keyCode == '32') { // space = fire
shoot(player_pos);
}
}
shoots = [];
function shoot(player_pos) {
shoots[shoots.length] = [player_pos, 500];
// pewpew = 5;
}
function isCollided(a, b) {
var a_left = parseInt(a.style.left);
var a_right = a_left + a.offsetWidth;
var a_top = parseInt(a.style.top);
var a_bottom = a_top + a.offsetHeight;
var b_left = parseInt(b.style.left);
var b_right = b_left + b.offsetWidth;
var b_top = parseInt(b.style.top);
var b_bottom = b_top + b.offsetHeight;
return !(
(a_left > b_right) ||
(a_right < b_left) ||
(a_top > b_bottom) ||
(a_bottom < b_top)
);
}
function gameLoop() {
// detect collision
var enemydiv = document.getElementById("enemy");
for(var i = 0; i < shoots.length; i++) {
if (shoots[i]) {
var shootdiv = document.getElementById('shoot' + i);
if (shootdiv && isCollided(shootdiv, enemydiv)) {
pewpew = 10;
}
}
}
// render shoots
for(var i = 0; i < shoots.length; i++) {
if (shoots[i]) {
var shootdiv = document.getElementById('shoot' + i);
if (!shootdiv) {
shootdiv = document.createElement('div');
shootdiv.setAttribute('id', 'shoot' + i);
shootdiv.setAttribute('class', 'shoot');
shootdiv.innerHTML = '|';
var body = document.getElementsByTagName('body')[0];
body.appendChild(shootdiv);
}
shootdiv.style.left = shoots[i][0];
shootdiv.style.top = shoots[i][1];
} else {
if (deldiv = document.getElementById('shoot' + i)) {
var body = document.getElementsByTagName('body')[0];
body.removeChild(deldiv);
}
}
}
// render pew pew
var pewpewdiv = document.getElementById("pewpew");
if (pewpew > 0) {
pewpewdiv.innerHTML = "pew! pew!";
} else {
pewpewdiv.innerHTML = "";
}
// render enemy
var enemydiv = document.getElementById("enemy");
enemydiv.style.left = 300;
enemydiv.style.top = 10;
// animate shoots
for(var i = 0; i < shoots.length; i++) {
if (shoots[i]) {
shoots[i][1] -= 10;
if (shoots[i][1] < 0) {
delete(shoots[i]);
}
}
}
// animate pew pew
if (pewpew > 0) {
pewpew -= 1;
}
setTimeout("gameLoop()", 100);
}
</script>
<style type="text/css">
* {
font-size: 2em;
color: #ff00ff;
font-family: helvetica, arial;
}
#player {
position: absolute;
bottom: 10%;
/* -webkit-transform: rotate(90deg);
-moz-transform: rotate(90deg); */
}
#enemy {
position: absolute;
top: 10%;
/* -webkit-transform: rotate(90deg);
-moz-transform: rotate(90deg); */
border-style: solid; border-width: 1px;
}
#pewpew {
position:absolute;
top: 10%;
right: 10%;
}
div.shoot {
position:absolute;
border-style: solid; border-width: 1px;
}
</style>
</head>
<body onload="gameLoop();">
<div id="enemy">3</div>
<div id="player"><</div>
<div id="pewpew"></div>
</body>
</html>