Benchmark: scrolltop - MeasureThat.net

HTML Preparation code:

<div id="parent">
<div id="child">
<div id="target">target</div>
<div class="noid">noid</div>
</div>
</div>

Script Preparation code:

function gid(id) {
	return document.getElementById(id);
}

duration = 400;
parent = gid("parent");
target = gid("target");
preoffset = parent.offsetHeight/2 + parseInt(getComputedStyle(parent).marginTop);


function anim (parent, target, duration) {
  //console.log(parent, target, duration);
  var oldtime = null;
  var scrolltoOffset = target.offsetTop - preoffset;
  function step (framereadytime) {
    if (!oldtime) oldtime = framereadytime;
    var progress = framereadytime - oldtime;
    //console.log(parent, target, duration);
    if(progress < duration && callback(progress) !== false) {
      rafid = requestAnimationFrame (step);
    }
  }
  function callback (delta) {
  	parent.scrollTop = scrolltoOffset * delta/duration;
  }
  var rafid = requestAnimationFrame (step);
  setTimeout(function() {
  	cancelAnimationFrame(rafid);
  }, duration)
}
function step1 (timestamp) {
    if (!start) start = timestamp;
  	var progress = timestamp - start;
  	parent.scrollTop = Math.min(progress*goffset / duration, goffset);
  	if (progress < duration) {
   		requestAnimationFrame(step1);
  	}
}
function anim1 (parent, target, duration) {
  	start = null;
  	goffset = target.offsetTop - preoffset;
  	requestAnimationFrame(step1);
}

Tests:

anim (parent, target, duration);
test
1+1

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result

test

Fastest: N/A

Slowest: N/A

Latest run results:

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

LLMs can make mistakes. Check important info.

I'll break down the provided JSON and explain what's being tested, compared, and what pros/cons come with each approach.

**Benchmark Definition**

The benchmark is defined by two parts:

1. **Script Preparation Code**: This code sets up the necessary variables and functions for the animation:
	* `gid(id)`: A function that returns an HTML element using its ID.
	* `duration`, `parent`, `target`, `preoffset`: Variables set based on the `parent` and `target` elements.
2. **Html Preparation Code**: This code defines the HTML structure with two nested `div`s (`parent` and `child`) containing a target element (`target`) and another non-existent element (`noid`).
3. The actual animation function is defined in the Script Preparation Code: `anim(parent, target, duration)`. It takes three parameters: the parent element, the target element, and the animation duration.

**Options Compared**

Two different approaches are compared:

1. **`anim(parent, target, duration)`**: This is the original implementation of the animation function.
2. **`anim1(parent, target, duration)`**: A modified version of the `anim` function with a few changes:
	* The `start` variable is removed, and instead, the timestamp is calculated directly in the `step1` function.
	* The `goffset` variable is set to the target element's offset.

**Pros/Cons**

The two approaches have different pros and cons:

**Original Implementation (`anim(parent, target, duration)`):**

Pros:

* Easier to understand and maintain
* More straightforward code

Cons:

* Uses a separate `start` variable, which might be considered unnecessary

**Modified Implementation (`anim1(parent, target, duration)`):**

Pros:

* Eliminates the need for a separate `start` variable
* Possibly optimized for performance (by avoiding unnecessary calculations)

Cons:

* More complex code due to the removal of the `start` variable
* Might be harder to understand and maintain

**Library Used: RequestAnimationFrame**

The `requestAnimationFrame` function is used in both implementations. This API allows for smooth animation by scheduling animation frames directly on the browser's event loop.

**Special JS Feature/Syntax**

None are mentioned, but it's worth noting that the use of `requestAnimationFrame` is a modern JavaScript feature introduced in Safari 5 and supported by most browsers since then.

**Alternatives**

Other alternatives for animation frameworks or libraries could be used instead of implementing the animation function from scratch. Some popular options include:

* jQuery Animation
* AnimeJS
* GSAP (GreenSock Animation Platform)
* Pixi.js

Keep in mind that these alternatives might offer more features, flexibility, and performance compared to a custom implementation.

I hope this explanation helps you understand what's being tested and compared in the benchmark!

Related benchmarks:

scrolltop (version: 13)

Comparing performance of: vs test

Created: 9 years ago by: Registered User

Jump to the latest result

test

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

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