1009679 - Layerize the scrollbar thumb / scroll indicator on Desktop

Status: RESOLVED FIXED

(Core :: Graphics: Layers, defect)

Description

[Markus Stange [:mstange]]

Attachment: v1

This was implemented for B2G in bug 813041 but not enabled for Desktop.

Comment 1

[Robert O'Callahan (:roc) (email my personal email if necessary)]

Comment on attachment 8421853 [details] [diff] [review]
v1

Review of attachment 8421853 [details] [diff] [review]:
-----------------------------------------------------------------

::: layout/base/nsLayoutUtils.cpp
@@ +1564,2 @@
>      // Treat the slider thumb as being as an active scrolled root
>      // on mobile so that it can move without repainting.

Fix comment

Comment 2

[Markus Stange [:mstange]]

https://tbpl.mozilla.org/?tree=Try&rev=e9359e213855

Comment 3

[Markus Stange [:mstange]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/83fd85b082d1

I had to make three tests as fuzzy on Linux because Linux has scrollbar thumbs with partially transparent pixels, and they blend differently with the background depending on whether they get painted into the same layer or are blended by the compositor.

Comment 4

[Ed Morley [:emorley]]

Push backed out for one of the commits inside it causing reftest + crashtest failures on OS X:
https://tbpl.mozilla.org/?tree=Mozilla-Inbound&rev=4b2db2286258&jobname=reftest|crashtest

remote:   https://hg.mozilla.org/integration/mozilla-inbound/rev/87349c65ee72
remote:   https://hg.mozilla.org/integration/mozilla-inbound/rev/055fe4ccf919

Comment 5

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

https://hg.mozilla.org/mozilla-central/rev/83fd85b082d1

Comment 6

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

https://hg.mozilla.org/mozilla-central/rev/055fe4ccf919

Comment 7

[Markus Stange [:mstange]]

It turns out that the scrubber of the <video> controls also gets its thumb layerized with these patches. The scrubber is a XUL <scale> which contains a xul:slider element in its anonymous content, just like scrollbars do.

The tbpl failures happened because the additional layers inside the video controls caused the container layer of the opacity effect to require an intermediate surface, and due to the component alpha text inside the controls that forced us to copy up the background into the container layer surface, and the background copying (CompositorOGL::CreateFBOWithTexture) checked the GLContext for errors and picked up an unrelated error left by an earlier test (see bug 1016437).

Comment 8

[Markus Stange [:mstange]]

https://tbpl.mozilla.org/?tree=Try&rev=0fea291b94cd

Comment 9

[Markus Stange [:mstange]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/a0586a5ec2da

Comment 10

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/a0586a5ec2da

Comment 11

[Alfred Kayser]

Themed scrollbars sometimes fail on Windows with custom themes such as Walnut and Littlefox.
Probably they need the same handdling as on MacOs:
    if ((aWidgetType == NS_THEME_SCROLLBAR ||
         aWidgetType == NS_THEME_SCROLLBAR_SMALL) &&