Jelly scroll example starts to desync from your drag-point

[Permik]

https://targetj.io/examples/g-jelly-scroll.html

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Hiya! I've noticed a bug that seems to affect every device that supports touch based scrolling.

How to reproduce:

1. Scroll a bit into the example as you'll need to have "open space" on the both sides of the scrollable area.
2. Start a scrolling gesture and note the point you're starting it at.
3. Swipe the scrollable area wildly to the left and right in a shaking motion.
4. Note that your finger is most probably not on the same number you started at.

Bonus: If you keep your finger still pressed here, sometimes the tracking completely gives up and the scroller still scrolls to a direction by just leaving your finger touching the screen.

Otherwise, the project looks cool! Thanks for making it open!

[wasfi2]

Thanks for reporting the first bug and for the clear explanation. I made a quick improvement today while fixing other issues, but there is still some drifting. I will work on a more robust fix in the near future.

[wasfi2]

I think I have resolved the drifting issue. Please review it and let me know. Thank you.

[Permik]

After testing the issue of leaving the finger pressed on the screen, the scroller doesn't drift off anymore, but the scroll position still desyncs.

How to replicate:

1. Scroll a bit into the scroller that you have space on either side of the scroll viewport.
2. Pick a point on the scroller where you start the scroll (e.g. 300)
3. Swipe wildly left and right on the scroller without lifting your finger.
4. Observe as you continue this, the value under your finger gets smaller and smaller.

[Permik]

Returning to this, this still seems to be an issue on touch devices. Just thought that you'd want a head's up.

[wasfi2]

Hey Permik, thanks for the head's up. I think it is fixed now when it uses window scrolling as shown in this example: https://targetjs.io/examples/g-Infinite-scrolling.html.
I also wrote a small section about scrolling at https://targetjs.io/docs/scrolling.html.
I think for accurate scrolling it is best to leave it to be handled by window events. The custom scrolling is handled synchronously and events get queued when the app is hit by more event than it can handled and some calculation gets off track as they all use the same cycle.

[Permik]

Oh wow, that was a fast one!
Now it works flawlessly, kudos.

[wasfi2]

Glad to hear it is fixed. Please let me know if you find any other issues. Thanks again for reporting it and following up.