Run results for: Setting Canvas Pixel Concat/Join/template vs Image data

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:87.0) Gecko/20100101 Firefox/87.0

Browser: Firefox 87

Operating system: Windows

Device Platform: Desktop

Date tested: 3 years ago

Test name	Executions per second
fillRect/concat	1217.2 Ops/sec
fillRect/join	1146.4 Ops/sec
1×1 Image Data	71.3 Ops/sec
fillRect/template	1144.5 Ops/sec

HTML Preparation code:

<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); }
fillRect/template
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); }

Run results for: Setting Canvas Pixel Concat/Join/template vs Image data

Testing the speed of various pixel setting methods. Forked to add template string.

fillRect/concat

fillRect/join

1×1 Image Data

fillRect/template