How does this compare to the classic css-native parallax effect? Before the scroll timeline APIs you'd use the "perspective" css property to create a container where the z plane is n pixels away from the screen, and then position each layer within it at a different z distance using transform: translateZ
That method is GPU accelerated too, so it is performant compared to some js solutions, and has worked well in every browser for around a decade
I like the idea of the scroll-timeline though, just keen to understand what the advantage is for this
No doubt quite a few folk with the same question. Keen to understand performance tradeoffs.
Obvious comparison note would be that the "new" method currently enjoys somewhat limited browser support (no Firefox without a flag, and only since Safari 26)
I was wondering the same thing. That translateZ is a bit fiddly to get right, so I could believe this is a bit easier to use, maybe? And presumably this could be used for other properties besides position, like colors, opacity or blurs.
The JS and bot check are for making additional functionality, beyond just showing the example, work easily. I.e. editing and sharing edits from a browser. If all you want is a static example, feel free to make it without these things.
You can make some really cool stuff with css scroll animations. I used SVG paths with a scroll animated dash offset to draw an image while scrolling. Zero javascript, it feels so smooth. https://thomaswelter.nl (the background)
In a world where it's increasingly overlooked, I'm glad the author mentions disabling it respecting user settings. I do think it should be reversed and only enabled with the `@media (prefers-reduced-motion: no-preference)`, but that is the opinion of someone who gets negative value from animations and is bemused by how much dev and compute time is spent on them.
That method is GPU accelerated too, so it is performant compared to some js solutions, and has worked well in every browser for around a decade
I like the idea of the scroll-timeline though, just keen to understand what the advantage is for this
Obvious comparison note would be that the "new" method currently enjoys somewhat limited browser support (no Firefox without a flag, and only since Safari 26)