Run details:
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/113.0.0.0 Safari/537.36
Chrome 113
Windows
Desktop
one year ago
Test name Executions per second
fillRect/concat 595.5 Ops/sec
fillRect/join 569.5 Ops/sec
1×1 Image Data 22.5 Ops/sec
HTML Preparation code:
AخA
 
1
<canvas id="c" width="800" height="300"></canvas>
Script Preparation code:
 
$c = document.getElementById('c');
$ctx = $c.getContext('2d');
$ctx.clearRect(0, 0, 800, 300);
$px = $ctx.createImageData(1, 1);
$pxls = [];
for (var i=0; i<10000; ++i) $pxls.push({
   x: Math.random() * 800 << 0,
   y: Math.random() * 300 << 0,
   r: Math.random() * 255 << 0,
   g: Math.random() * 255 << 0,
   b: Math.random() * 255 << 0,
   a: Math.random() * 128 << 0 + 128
});
$i = 0;
Tests:
  • fillRect/concat

     
    for (var i=500;i--;){
    var px = $pxls[$i++ % 10000];
    $ctx.fillStyle = 'rgba(' + px.r + ',' + px.g + ',' + px.b + ',' + (px.a / 255) + ')';
    $ctx.fillRect(px.x, px.y, 1, 1);
    }
  • fillRect/join

     
    for (var i=500;i--;){
    var px = $pxls[$i++ % 10000];
    $ctx.fillStyle = 'rgba(' + [px.r,px.g,px.b,px.a/255].join() + ')';
    $ctx.fillRect(px.x, px.y, 1, 1);
    }
  • 1×1 Image Data

     
    for (var i=500;i--;){
    var px=$pxls[$i++ % 10000], d=$px.data;
    d[0] = px.r;
    d[1] = px.g;
    d[2] = px.b;
    d[3] = px.a;
    $ctx.putImageData($px, px.x, px.y);
    }