Mass and momentum

[antonioberetini]

Is it possible to control mass and momentum? I feel that with a bit more mass and momentum, the scroll would feel more natural. For instance comparing it to iOS native scroll, on shorter swipes, scroll moves longer and it eases out before it stops.

[idiotWu]

You can use the damping option to control the easing.

[antonioberetini]

Yeah I tired several options- if I go super low 0.07 even down to 0.04 (which feels close to ios), I it feels very smooth but it's super jumpy. If I go higher with damping it's super stiff. Mass would do the magic here.

[idiotWu]

(Not sure momentum is a proper word here, although people are calling it "momentum-based scrolling".)

As mass directly proportional to momentum, you can use the following plugin to multiply the momentum when releasing finger:

import Scrollbar, { ScrollbarPlugin } from 'smooth-scrollbar';
import OverscrollPlugin from 'smooth-scrollbar/plugins/overscroll'; // if you are using this

class MassPlugin extends ScrollbarPlugin {
  static pluginName = 'mass';

  static defaultOptions = {
    m: 1.0,
  };

  override transformDelta(delta: { x: number, y: number }, fromEvent: Event): { x: number, y: number } {
    if (fromEvent.type === 'touchend') {
      return {
        x: delta.x * this.options.m,
        y: delta.y * this.options.m,
      };
    }

    return delta;
  }
}

Scrollbar.use(MassPlugin, OverscrollPlugin);

Scrollbar.init(elem, {
  plugin: {
    mass: { m: 1.5 },
  },
});

[idiotWu]

I just tweaked some calculations to make the touch scrolling more natural, especially with damping: 0.05 on mobile devices. Can you update to v8.7.1 to give it a try?

[antonioberetini]

Is it live on your demo page? Get Outlook for Android<https://aka.ms/AAb9ysg>

…

________________________________ From: Daofeng Wu ***@***.***> Sent: Friday, December 24, 2021 11:32:00 AM To: idiotWu/smooth-scrollbar ***@***.***> Cc: Tony Beretini ***@***.***>; Author ***@***.***> Subject: Re: [idiotWu/smooth-scrollbar] Mass and momentum (Issue #427) I just tweaked some calculations to make the touch scrolling more natural, especially with damping: 0.05 on mobile devices. Can you update to v8.7.1<https://github.com/idiotWu/smooth-scrollbar/releases/tag/v8.7.1> to give it a try? — Reply to this email directly, view it on GitHub<#427 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/APUUMIBXHCW2E24IDWXJYFDUSSVBBANCNFSM5KV5LMUA>. You are receiving this because you authored the thread.Message ID: ***@***.***>

[idiotWu]

Yeah, but I didn't add the MassPlugin into it.

[antonioberetini]

Dude you are the God! The new version on your demo site behaves prettymuch like ios now with the following settings

[antonioberetini]

I just noticed that scroll is jittering after this update while slowing down

[idiotWu]

I just noticed that scroll is jittering after this update while slowing down

Have you unchecked the renderByPixels option?

[antonioberetini]

Yes Get Outlook for Android<https://aka.ms/AAb9ysg>

…

________________________________ From: Daofeng Wu ***@***.***> Sent: Saturday, December 25, 2021 11:36:12 AM To: idiotWu/smooth-scrollbar ***@***.***> Cc: Tony Beretini ***@***.***>; Author ***@***.***> Subject: Re: [idiotWu/smooth-scrollbar] Mass and momentum (Issue #427) I just noticed that scroll is jittering after this update while slowing down Have you unchecked the renderByPixels option? — Reply to this email directly, view it on GitHub<#427 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/APUUMIFBOC2Z63B5SM5XUFLUSX6IZANCNFSM5KV5LMUA>. You are receiving this because you authored the thread.Message ID: ***@***.***>

[idiotWu]

It behaves smoothly in my environments (MacBook Pro 13, 2019; Pixel 4 w/ Android 12). Maybe damping: 0.02 brings too many frames that slow down the rendering?

[antonioberetini]

Could be - I i don't think this was the case in the last version. I could be wrong ... Google Pixel 6 Pro here and iPhone 12 Pro MAX Get Outlook for Android<https://aka.ms/AAb9ysg>

…

________________________________ From: Daofeng Wu ***@***.***> Sent: Saturday, December 25, 2021 11:40:19 AM To: idiotWu/smooth-scrollbar ***@***.***> Cc: Tony Beretini ***@***.***>; Author ***@***.***> Subject: Re: [idiotWu/smooth-scrollbar] Mass and momentum (Issue #427) It behaves smoothly in my environments (MacBook Pro 13, 2019; Pixel 4 w/ Android 12). Maybe damping: 0.02 brings too many frames that slow down the rendering? — Reply to this email directly, view it on GitHub<#427 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/APUUMIBPJQPT5SYI3NUJAVDUSX6YHANCNFSM5KV5LMUA>. You are receiving this because you authored the thread.Message ID: ***@***.***>