Comment by Rohansi
20 hours ago
> This is the kind of thing usually a human notices and says 'dont do that, that is kind of crazy'.
It's not crazy. That is literally what 99.99% of video games do. They repaint everything constantly, only limited by either your vsync rate or hardware.
A website shouldn't be pinning CPU or GPU. When people run a game they expect some sort of battery drain. People don't expect that some websites will thrash your CPU/GPU like a game.
> A website shouldn't be pinning CPU or GPU.
That's exactly what I was saying. Rendering a few widgets shouldn't pin your CPU or GPU because it's so little work.
This page, however, has an animated SVG and moving DOM elements in the header which consume far more resources than the widgets it is trying to showcase. Compare usage before and after deleting the header element (`section.hero`) in the inspector to see for yourself.
> > A website shouldn't be pinning CPU or GPU.
> That's exactly what I was saying. Rendering a few widgets shouldn't pin your CPU or GPU because it's so little work.
Your comment doesn't say this at all:
> > This is the kind of thing usually a human notices and says 'dont do that, that is kind of crazy'.
> It's not crazy. That is literally what 99.99% of video games do. They repaint everything constantly, only limited by either your vsync rate or hardware.
Am I missing something? Are you referring to some other part of the thread?
1 reply →
> Yes my car is running all night while it stands in front of my house, but it's not really a waste of resources or a nuisance because generators do the same thing.
Your analogy is wrong. The rendering engine is the generator.
You know nothing about software if you really think this.
He's right - the DOM also has observers.
The difference is what is rendered, not that observers are involved and the concept of looping.
Millions use React - you want to talk about performance?
It's mining Bitcoin!
The state of the web when you want to compare a website to the most intensive thing a pc can do.
Presumably in a video game the majority of the screen changes every frame. Not so in web pages.
My point was more that rendering a few widgets at 60+ FPS is nothing for anything with a GPU, and everything has a GPU these days.
Anyway, something like this only needs to paint when states change or animations are running. That's an easy optimization to make here if it doesn't do it already. And games don't even bother with it, they repaint all UI even if it doesn't change.
Waste the cycles, everyone has too many cycles, is it even waste if the cycles would just go unused, GPUs are expensive, they better do their bit, who's got no GPU, go play somewhere else without your GPU, pal. It's all a game, anyway.
Point being: your comment made me sad and I needed to lighten myself up a bit.
2 replies →
Video games only get away with this because their energy draw is obvious: one launched the video game, so one expects the power draw. Visiting a web page does not have that action-reaction causality in people’s minds. Having a random web page introduce maximally-inefficient repaints also leads browsers to start reducing timeslices — especially those with any sort of power drain cognizance, such as Safari — which, here, leads to hella janky animations that can’t cope without their inefficient repaint loop.
All this work to replicate the animated blobbiness of Liquid Glass. I thought everyone hated it! So, then, why is this a thing?
5 replies →
Is your browser running the javascript event loop on the GPU? Because mine isn't
A website isn’t a videogame
Braindead take.
A videogame is expensive to render because of several MB models, constantly moving camera, and other things.
The concept of observing elements is not even new.
I get what you're saying.
These downvoters act like native JS doesn't do the exact same thing with event listening and observing the DOM. So does React and other FE frameworks.
Philip J Fry is either being disingenuous or genuinely doesn't know that game rendering has often several MB models, is often raycasting, maintaining camera calculus, and a lot more.
If you take about optimizing then games are the prime example of doing that. You don't load textures every frame into gpu memory. Tou don't load vertices into memory every frame. Sure they repaint every pixel every frame. But low level your display driver is doing that anyway. The cpu cycles are not in sending the RGB value to each pixel. We are far beyond that bandwidth issue. Recalculating every single position in a css styled document is pretty heavy. There are millions of calculations done to solve flex boxes, floats, percentual widths etc. this example is doing something like that. Super heavy. Super inefficient. Super bad.
The browser and OS does that as well (unless absolute zero updates and you don't even move your pointer around).
But many smaht people out there don't know that.
This is just plain false. Retained UIs like the DOM and what your OS uses only ever render when something changes, so the vast majority of the time they sit idle. There's extensive effort throughout the entire stack to do as little work as possible.
For instance, the mouse cursor is composited on the GPU during scanout. That means simply moving your cursor requires zero rendering.
Another example: When typing only the newly typed character and caret are rendered. The rest of your entire screen is reused.
> Another example: When typing only the newly typed character and caret are rendered. The rest of your entire screen is reused.
You're right that they avoid unnecessary painting but it is not this granular anymore. It used to be but rendering is so much faster these days where it is cheaper to just render a bit more than tracking dirty regions. It's easily visible on Android where you can enable "Show view updates" and see the entire textbox view updates when the cursor flashes. The docs say the same thing.
https://developer.android.com/reference/android/view/View#in...
That doesn't mean that the process stops, it runs indefinitely because it has to.
The DOM does this. React does this.
Did you know CSS even invokes the GPU for certain tasks?
You guys really need more experience. I can't believe how many people apparently know nothing at all about web dev and computers.