Add a couple of more variable bindings, make all the set visual gear values optional, to allow skipping trailing params or specifying ones in the middle as nil to not set. Should make using it more convenient in simple cases.
<!doctype html>
<html>
<head>
<title>Hedgewars Theme Editor</title>
<script type="text/javascript">
var sky, clouds, horizont, water, land, border;
var skyColor, waterTopColor, waterBottomColor;
var elements = 7;
var landArray;
function landFunction(x){
return 384 - 192 * Math.sin(x * Math.PI/512);
}
function tryToDraw(){
if (--elements <= 0) {
draw();
}
}
function load(){
var canvas = document.getElementById('preview');
if (canvas.getContext){
var ctx = canvas.getContext('2d');
ctx.fillStyle = '#0b294b';
ctx.fillRect(0, 0, 512, 384);
ctx.font = "40pt Arial";
ctx.fillStyle = '#2b7bd5';
ctx.fillText('Loading Images...', 32, 212);
}
sky = new Image();
sky.onload = tryToDraw;
sky.src = 'http://hedgewars.googlecode.com/hg/share/hedgewars/Data/Themes/Nature/Sky.png';
clouds = new Image();
clouds.onload = tryToDraw;
clouds.src = 'http://hedgewars.googlecode.com/hg/share/hedgewars/Data/Graphics/Clouds.png';
horizont = new Image();
horizont.onload = tryToDraw;
horizont.src = 'http://hedgewars.googlecode.com/hg/share/hedgewars/Data/Themes/Nature/horizont.png';
land = new Image();
land.onload = tryToDraw;
land.src = 'http://hedgewars.googlecode.com/hg/share/hedgewars/Data/Themes/Nature/LandTex.png';
border = new Image();
border.onload = tryToDraw;
border.src = 'http://hedgewars.googlecode.com/hg/share/hedgewars/Data/Themes/Nature/Border.png';
water = new Image();
water.onload = tryToDraw;
water.src = 'http://hedgewars.googlecode.com/hg/share/hedgewars/Data/Graphics/BlueWater.png';
landArray = new Array(512);
for (var x = 0; x < landArray.length; x++)
landArray[x] = landFunction(x);
skyColor = '#131252';
document.getElementById('skyColor').value = skyColor;
waterTopColor = '#555C9D';
document.getElementById('waterTopColor').value = waterTopColor;
waterBottomColor = '#343C7D';
document.getElementById('waterBottomColor').value = waterBottomColor;
tryToDraw();
}
function draw(){
var canvas = document.getElementById('preview');
if (canvas.getContext){
var ctx = canvas.getContext('2d');
ctx.fillStyle = skyColor;
ctx.fillRect(0, 0, 512, 384);
ctx.drawImage(sky, 0, 64, 512, 256);
for (var i = 0; i < 4; i++)
ctx.drawImage(clouds, 0, i * 128, 256, 128, i * 128, 64, 128, 64);
ctx.drawImage(horizont, 0, 192, 512, 128);
ctx.save();
ctx.beginPath();
ctx.moveTo(0, 384);
for (var x = 0; x < landArray.length; x++)
ctx.lineTo(x, landArray[x]);
ctx.clip();
for (var i = 0; i < 2; i++)
for (var k = 0; k < 2; k++)
ctx.drawImage(land, i * 320, k * 240, 320, 240);
ctx.restore();
var k = 0;
for (var x = 0; x < landArray.length; x++) {
if (++k == 64)
k = 0;
ctx.drawImage(border, k, 0, 2, 16, x, landArray[x] - 4, 1, 8);
}
var gradient = ctx.createLinearGradient(0, 320, 0, 384);
gradient.addColorStop(0, waterTopColor);
gradient.addColorStop(1, waterBottomColor);
ctx.fillStyle = gradient;
ctx.fillRect(0, 320, 512, 384);
for (var i = 0; i < 8; i++)
ctx.drawImage(water, i * 64, 308, 64, 24);
}
}
</script>
<style type="text/css">
canvas { border: 1px solid black; }
</style>
</head>
<body onload="load();">
<h1>Hedgewars Theme editor</h1>
<canvas id="preview" width="512" height="384">Sorry, your browser does not support Canvas.</canvas><br>
<table>
<tr><td>Sky:</td><td>
<input id="sky" type="file" accept="image/png" onchange="sky.src = window.URL.createObjectURL(this.files[0])"></input>
</td></tr>
<tr><td>Sky Color:</td><td>
<input id="skyColor" type="color" onchange="skyColor = this.value; draw()"></input>
</td></tr>
<tr><td>Clouds:</td><td>
<input id="clouds" type="file" accept="image/png" onchange="clouds.src = window.URL.createObjectURL(this.files[0])"></input>
</td></tr>
<tr><td>Horizont:</td><td>
<input id="horizont" type="file" accept="image/png" onchange="horizont.src = window.URL.createObjectURL(this.files[0])"></input>
</td></tr>
<tr><td>Land:</td><td>
<input id="land" type="file" accept="image/png" onchange="land.src = window.URL.createObjectURL(this.files[0])"></input>
</td></tr>
<tr><td>Border:</td><td>
<input id="border" type="file" accept="image/png" onchange="border.src = window.URL.createObjectURL(this.files[0])"></input>
</td></tr>
<tr><td>Water:</td><td>
<input id="water" type="file" accept="image/png" onchange="water.src = window.URL.createObjectURL(this.files[0])"></input>
</td></tr>
<tr><td>Water Top Color:</td><td>
<input id="waterTopColor" type="color" onchange="waterTopColor = this.value; draw()"></input>
</td></tr>
<tr><td>Water Bottom Color:</td><td>
<input id="waterBottomColor" type="color" onchange="waterBottomColor = this.value; draw()"></input>
</td></tr>
</table>
</body>
</html>