Performance Issues on iphones specialy Safari but also Chrome on iphone.

[hantha]

Hello Guys,  

it's my first Forum Article.
I'm using GSAP for nearly a year now. I'm using GSAP + GsapSmoothScroll + ScrollTrigger and Barba.js  I have some slightly complex Animations on my Site and its extremely laggy on iPhone Safari I tried a lot of Solutions that I found hear, but nothing really works.  Does someone have some Ideas how to fix. Here is a Link to the Website:
This is my config for the ScrollSmoother. 
The Lag is specially on the page uid42 thats the link i put in hear. The other pages are ok not perfekt but ok: 
I hope its enough information.
 

  scroll = ScrollSmoother.create({

                smooth: 0.2, // how long (in seconds) it takes to "catch up" to the native scroll position

                effects: true, // looks for data-speed and data-lag attributes on elements

                ignoreMobileResize: isMobile() && !document.querySelector("#uid1") ? true : false,

                normalizeScroll: isMobile() && !document.querySelector("body:not(#uid42)") ? true : false,

            })

On a Mission (hantha.net)


Hope someone could help me. 

[GSAP Helper]

Hi there! Sorry to hear you've run into some performance issues.

A lot of performance problems are down to how browsers and graphics rendering work. It's very difficult to troubleshoot blind and performance is a DEEP topic, but here are some tips: 

1. Try setting will-change: transform on the CSS of your moving elements. 
2. Make sure you're animating transforms (like x, y) instead of layout-affecting properties like top/left. 
3. Definitely avoid using CSS filters or things like blend modes. Those are crazy expensive for browsers to render.
4. Be very careful about using loading="lazy" on images because it forces the browser to load, process, rasterize and render images WHILE you're scrolling which is not good for performance. 
5. Make sure you're not doing things on scroll that'd actually change/animate the size of the page itself (like animating the height property of an element in the document flow)
6. Minimize the area of change. Imagine drawing a rectangle around the total area that pixels change on each tick - the bigger that rectangle, the harder it is on the browser to render. Again, this has nothing to do with GSAP - it's purely about graphics rendering in the browser. So be strategic about how you build your animations and try to keep the areas of change as small as you can.
7. If you're animating individual parts of SVG graphics, that can be expensive for the browser to render. SVGs have to fabricate every pixel dynamically using math. If it's a static SVG that you're just moving around (the whole thing), that's fine - the browser can rasterize it and just shove those pixels around...but if the guts of an SVG is changing, that's a very different story. 
8. data-lag is a rather expensive effect, FYI. Of course we optimize it as much as possible but the very nature of it is highly dynamic and requires a certain amount of processing to handle correctly.
9. I'd recommend strategically disabling certain effects/animations and then reload it on your laptop and just see what difference it makes (if any). 

Ultimately there's no silver bullet, like "enable this one property and magically make a super complex, graphics-heavy site run perfectly smoothly even on 8 year old phones" 

I hope this helps!  💚

[hantha]

Thanks for the infos and Tipps, 
i will try to implement some off your ideas and hopefully it makes some diffrence