For fun I am trying to create a visualization of different sorting algorithms, but I've run into an issue with Canvas animations.
I assumed I would just be able to call a draw function within the sorter method, but this causes the browser to lock up until the array is fully sorted and then draws some middle frame.
How would I go about animating from within the sorting methods? Below is the code I have so far, I wouldn't run this snippet as it will hang the tab for a few seconds.
N = 250; // Array Size
XYs = 5; // Element Visual Size
Xp = 1; // Start Pos X
Yp = 1; // Start Pos Y
var canvas;
var l = Array.apply(null, {
length: N
}).map(Number.call, Number);
Array.prototype.shuffle = function() {
var i = this.length,
j, temp;
if (i == 0) return this;
while (--i) {
j = Math.floor(Math.random() * (i + 1));
temp = this[i];
this[i] = this[j];
this[j] = temp;
}
return this;
}
function map_range(x, in_min, in_max, out_min, out_max) {
return (x - in_min) * (out_max - out_min) / (in_max - in_min) + out_min;
}
function rainbow(x) {
var m = map_range(x, 0, N, 0, 359);
return 'hsl(' + m + ',100%,50%)';
}
function init() {
canvas = document.getElementById('canvas');
l.shuffle();
draw();
bubbleSort(l);
}
function draw() {
if (canvas.getContext) {
var ctx = canvas.getContext('2d');
for (var i = 0; i < l.length; i++) {
ctx.fillStyle = rainbow(l[i]);
ctx.fillRect((Xp * i) * XYs, Yp * XYs, XYs, XYs);
}
}
}
function bubbleSort(a) {
var swapped;
do {
swapped = false;
for (var i = 0; i < a.length - 1; i++) {
if (a[i] > a[i + 1]) {
var temp = a[i];
a[i] = a[i + 1];
a[i + 1] = temp;
swapped = true;
draw();
setTimeout(function() {}, 10);
}
}
} while (swapped);
}
<html>
<body onload="init();">
<canvas id="canvas" width="1500" height="1500"></canvas>
</body>
</html>
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