Benchmark: Setting Canvas Pixel actually working

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/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);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
fillRect/join
1×1 Image Data

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/115.0

Browser/OS: Firefox 115 on Linux

View result in a separate tab

Test name	Executions per second
fillRect/join	411.5 Ops/sec
1×1 Image Data	9868.2 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

LLMs can make mistakes. Check important info.

Measuring performance differences is an important aspect of software development, and tools like MeasureThat.net provide valuable insights.

The provided JSON represents a JavaScript microbenchmark test case that compares two approaches for rendering 1x1 pixels on a canvas element. Here's a breakdown of what's being tested:

**Script Preparation Code**

This code sets up the necessary variables and contexts for the benchmark:
```javascript
$c = document.getElementById('c'); // Get the canvas element
$ctx = $c.getContext('2d'); // Get the 2D drawing context
$ctx.clearRect(0, 0, 800, 300); // Clear the canvas to a solid color (not relevant for this benchmark)
$px = $ctx.createImageData(1, 1); // Create an image data object for a single pixel
$pxls = []; // Array to store pixel data

for (var i=0; i<10000; ++i) {
  $pxls.push({ // Generate 10,000 pixels with random RGB and alpha values
    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; // Reset the loop counter
```
**Html Preparation Code**

This code sets up the HTML structure for the benchmark:
```html
<canvas id="c" width="800" height="300"></canvas>
```
**Test Cases**

There are two test cases:

1. **fillRect/join**
This test case uses the `fillRect` method to draw a single pixel, and then joins the RGBA values into a string using the `join()` method. The benchmark compares the performance of this approach.
2. **1×1 Image Data**
This test case uses the `putImageData` method to draw a single pixel from an image data object. The benchmark compares the performance of this approach.

**Library: `createImageData`**

The `createImageData` method creates an image data object that can be used to store pixel data. In this benchmark, it's used to create an array of pixels with random RGB and alpha values.

**Pros and Cons of Each Approach**

1. **fillRect/join**: This approach is simple and efficient, but it may not work well for all types of pixels (e.g., those with alpha values that are not multiples of 128).
2. **1×1 Image Data**: This approach uses a more explicit way of storing pixel data, which can be beneficial for certain use cases. However, it may be slower than the `fillRect` method.

**Other Considerations**

* The benchmark uses a large number of pixels (10,000) to ensure that the results are representative.
* The canvas element is set to a fixed size (800x300), which ensures that the benchmark runs consistently across different devices.
* The benchmark does not account for any potential differences in rendering performance between browsers or devices.

**Alternatives**

Other ways to render pixels on a canvas element include:

* Using `getContext('webgl')` and drawing pixels using WebGL APIs
* Using a library like Pixi.js or Fabric.js, which provide optimized pixel rendering capabilities
* Using a library like WebAssembly (WASM), which allows for low-level pixel manipulation

These alternatives may offer better performance or more features than the benchmarked approaches, but they also introduce additional complexity and dependencies.

Related benchmarks:

Setting Canvas Pixel actually working (version: 0)

Comparing performance of: fillRect/join vs 1×1 Image Data

Created: one year ago by: Guest

Jump to the latest result

fillRect/join

1×1 Image Data

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):