Bug 218857

Summary:

Use native animations for scroll-behavior:smooth on Mac

Product:

WebKit

Reporter:

cathiechen <cathiechen>

Component:

Scrolling

Assignee:

Martin Robinson <mrobinson>

Status:

RESOLVED INVALID

Severity:

Normal

CC:

changseok, esprehn+autocc, ews-watchlist, fred.wang, glenn, kondapallykalyan, mrobinson, pdr, rik, simon.fraser, webkit-bug-importer

Priority:

Keywords:

InRadar

Version:

WebKit Nightly Build

Hardware:

Unspecified

OS:

Unspecified

See Also:

https://bugs.webkit.org/show_bug.cgi?id=230310

Bug Depends on:

Bug Blocks:

188043

Attachments:

Description	Flags
Patch	none
Patch	none
Patch	none
Patch	ews-feeder: commit-queue-
Patch	none

Description cathiechen 2020-11-12 10:24:50 PST

Try to use the native scroll animation of Mac (scrolling momentum) for smooth scroll.

Comment 1 Radar WebKit Bug Importer 2020-11-19 10:25:12 PST

<rdar://problem/71591918>

Comment 2 Martin Robinson 2021-06-29 02:18:59 PDT

Created attachment 432463 [details]
Patch

Comment 3 Martin Robinson 2021-06-30 03:48:14 PDT

Created attachment 432581 [details]
Patch

Comment 4 cathiechen 2021-07-02 01:54:41 PDT

Comment on attachment 432581 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=432581&action=review

> Source/WebCore/platform/ScrollAnimator.cpp:-125
> -    m_scrollAnimation->setCurrentPosition(adjustedPosition);

I wonder would this change affect the platform still using m_scrollAnimation?

> Source/WebCore/platform/ScrollView.cpp:-540
> -    setScrollBehaviorStatus(ScrollBehaviorStatus::NotInAnimation);

Looks like we can also remove this in RenderLayerScrollableArea::scrollToOffset()?

Comment 5 Martin Robinson 2021-07-02 02:11:08 PDT

Created attachment 432772 [details]
Patch

Comment 6 Martin Robinson 2021-07-02 02:12:49 PDT

(In reply to cathiechen from comment #4)

Thanks for taking a look at this!

> 
> View in context:
> https://bugs.webkit.org/attachment.cgi?id=432581&action=review
> 
> > Source/WebCore/platform/ScrollAnimator.cpp:-125
> > -    m_scrollAnimation->setCurrentPosition(adjustedPosition);
> 
> I wonder would this change affect the platform still using m_scrollAnimation?

I don't think this will, because setCurrentPosition is always called before starting a new animation with m_scrollAnimation.

> > Source/WebCore/platform/ScrollView.cpp:-540
> > -    setScrollBehaviorStatus(ScrollBehaviorStatus::NotInAnimation);
> 
> Looks like we can also remove this in
> RenderLayerScrollableArea::scrollToOffset()?

Nice catch! I thought I had gotten all of these, but I missed one.

I've uploaded a new version of the change.

Comment 7 Martin Robinson 2021-07-06 07:46:13 PDT

Created attachment 432928 [details]
Patch

Comment 8 Martin Robinson 2021-07-06 08:15:21 PDT

Created attachment 432931 [details]
Patch

Comment 9 Martin Robinson 2021-09-23 08:00:17 PDT

Now that ScrollAnimator and ScrollAnimatorMac use the same smooth animation, this change is no longer valid.

See: https://bugs.webkit.org/show_bug.cgi?id=230445

Comment 10 Simon Fraser (smfr) 2021-09-23 09:57:04 PDT

We still want to run smooth scrolling animations in the UI process on iOS, but we can do that via a separate bug.

Comment 11 Martin Robinson 2021-09-24 09:18:40 PDT

(In reply to Simon Fraser (smfr) from comment #10)
> We still want to run smooth scrolling animations in the UI process on iOS,
> but we can do that via a separate bug.

That's right. If I'm not mistaken it's tracked by: https://bugs.webkit.org/show_bug.cgi?id=204936.