947062 - Layerize animated background-position

Status: RESOLVED FIXED

(Core :: Graphics: Layers, defect)

Description

[Benoit Girard (:BenWa)]

Testcase: http://787.aircanada.com/en?mpch=ads

We scroll the page at 6 FPS on retina. We should layerize background-position. Even if the element isn't moving, it can be represented by a display item that is moving and thus we should be able to generate a layer that stays in place by modifying the valid region + transform to force the layer to rotate the contents without moving or repainting the whole thing.

Comment 1

[Benoit Girard (:BenWa)]

Attachment: testcase

Comment 2

[Benoit Girard (:BenWa)]

Attachment: testcase2 - elem doesn't move

Comment 3

[Markus Stange [:mstange]]

We can make the nsDisplayBackgroundImage create an ImageLayer if the frame's LayerActivity tells us that the background-position property is animated.

Comment 4

[Benoit Girard (:BenWa)]

Here's another example:
https://www.reddit.com/r/kerbalspaceprogram/

Currently the theme for this subreddit is a circular clip with an animated ground/cloud layer. With mask layers and animated background position we should be able to layerize this animation.

Comment 5

[Markus Stange [:mstange]]

Attachment: MozReview Request: Bug 947062 - Make background-position inline-style changes and CSS animations trigger layer activity. r?roc

Bug 947062 - Make background-position inline-style changes and CSS animations trigger layer activity. r?roc

Comment 6

[Markus Stange [:mstange]]

Attachment: MozReview Request: Bug 947062 - Refactor nsDisplayBackgroundImage::GetLayerState. r?mattwoodrow

Bug 947062 - Refactor nsDisplayBackgroundImage::GetLayerState. r?mattwoodrow

Comment 7

[Markus Stange [:mstange]]

Attachment: MozReview Request: Bug 947062 - Layerize background images with animated background-position if possible. r?mattwoodrow

Bug 947062 - Layerize background images with animated background-position if possible. r?mattwoodrow

Comment 8

[Markus Stange [:mstange]]

The examples in this bug won't layerize until we support ImageLayers for clipped and repeated images, but these patches lay the groundwork.

Comment 9

[Matt Woodrow (:mattwoodrow)]

Comment on attachment 8679497 [details]
MozReview Request: Bug 947062 - Refactor nsDisplayBackgroundImage::GetLayerState. r?mattwoodrow

https://reviewboard.mozilla.org/r/23437/#review20939

::: layout/base/nsDisplayList.cpp:2522
(Diff revision 1)
> + 

Trailing whitespace!

Comment 10

[Matt Woodrow (:mattwoodrow)]

Comment on attachment 8679498 [details]
MozReview Request: Bug 947062 - Layerize background images with animated background-position if possible. r?mattwoodrow

https://reviewboard.mozilla.org/r/23439/#review20941

Comment 11

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

Comment on attachment 8679496 [details]
MozReview Request: Bug 947062 - Make background-position inline-style changes and CSS animations trigger layer activity. r?roc

https://reviewboard.mozilla.org/r/23435/#review20969

Comment 12

[Markus Stange [:mstange]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/bbb83e48dbcef91b0efbcde557c9a4317b82da74
Bug 947062 - Make background-position inline-style changes and CSS animations trigger layer activity. r=roc

https://hg.mozilla.org/integration/mozilla-inbound/rev/d9da665e6f0dd1713e9e80c51edd54ca17998677
Bug 947062 - Refactor nsDisplayBackgroundImage::GetLayerState. r=mattwoodrow

https://hg.mozilla.org/integration/mozilla-inbound/rev/7e3476b5b99d8b18500ef3b6f41f6a0e9a915d99
Bug 947062 - Layerize background images with animated background-position if possible. r=mattwoodrow

Comment 13

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

https://hg.mozilla.org/mozilla-central/rev/bbb83e48dbce
https://hg.mozilla.org/mozilla-central/rev/d9da665e6f0d
https://hg.mozilla.org/mozilla-central/rev/7e3476b5b99d

Comment 14

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/releases/mozilla-b2g44_v2_5/rev/bbb83e48dbce
https://hg.mozilla.org/releases/mozilla-b2g44_v2_5/rev/d9da665e6f0d
https://hg.mozilla.org/releases/mozilla-b2g44_v2_5/rev/7e3476b5b99d