ScrollTrigger animation jerks on mobile

[Jusi]

Hey

I'm using GSAP for the first time. I created some basic scrolltrigger animations but experienced that my animation jerks a bit on mobile. I use a iPhone 13 to test.

 

Is this already too much animation? Would SmoothScroller help in anyway? I heard that mobile handles scrolling slower or something similar than a desktop.

 

Here is my simple website:

https://wwsite.justin-winistoerfer.dev/

 

thanks in advance

[GSAP Helper]

It's pretty tough to troubleshoot without a minimal demo - the issue could be caused by CSS, markup, a third party library, your browser, an external script that's totally unrelated to GSAP, etc. Would you please provide a very simple CodePen or Stackblitz that demonstrates the issue? 

 

Please don't include your whole project. Just some colored <div> elements and the GSAP code is best. See if you can recreate the issue with as few dependancies as possible. If not, incrementally add code bit by bit until it breaks. Usually people solve their own issues during this process! If not, then at least we have a reduced test case which greatly increases your chances of getting a relevant answer.

 

Here's a starter CodePen that loads all the plugins. Just click "fork" at the bottom right and make your minimal demo: 

See the Pen aYYOdN by GreenSock (@GreenSock) on CodePen

 

Using a framework/library like React, Vue, Next, etc.? 

CodePen isn't always ideal for these tools, so here are some Stackblitz starter templates that you can fork and import the gsap-trial NPM package for using any of the bonus plugins: 

• React (please read this article!)
• Next
• Svelte
• Sveltekit
• Vue
• Nuxt

 

Please share the StackBlitz link directly to the file in question (where you've put the GSAP code) so we don't need to hunt through all the files. 

 

Once we see an isolated demo, we'll do our best to jump in and help with your GSAP-specific questions. 

[Rodrigo]

Hi @Jusi and welcome to the GSAP Forums!

 

35 minutes ago, Jusi said:

I heard that mobile handles scrolling slower or something similar than a desktop.

What happens in mobile devices is that the scroll is handled in a different thread, that's why sometimes there is some lag in terms of the updates. For that we have normalize scroll in order to move the scrolling into the JS thread and keep everything in sync:

https://gsap.com/docs/v3/Plugins/ScrollTrigger/static.normalizeScroll()

 

I recommend you to use normalizeScroll only on touch devices, for that you can use the isTouch property ScrollTrigger offers to give you a basic information regarding the device being used:

https://gsap.com/docs/v3/Plugins/ScrollTrigger/static.isTouch

 

Hopefully this helps.

Happy Tweening!