Benoit Girard (:BenWa) Reporter
	Description • 11 years ago

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.

	Markus Stange [:mstange] Assignee
	Comment 3 • 9 years ago

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

	Benoit Girard (:BenWa) Reporter
	Comment 4 • 9 years ago

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.

	Markus Stange [:mstange] Assignee
	Comment 5 • 9 years ago

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

	Markus Stange [:mstange] Assignee
	Comment 6 • 9 years ago

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

	Markus Stange [:mstange] Assignee
	Comment 7 • 9 years ago

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

	Markus Stange [:mstange] Assignee
	Comment 8 • 9 years ago

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

	Matt Woodrow (:mattwoodrow)
	Comment 9 • 9 years ago

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!

	Matt Woodrow (:mattwoodrow)
	Comment 10 • 9 years ago

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

	Robert O'Callahan (:roc) (email my personal email if necessary)
	Comment 11 • 9 years ago

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

	Markus Stange [:mstange] Assignee
	Comment 12 • 9 years ago

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

	Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)
	Comment 13 • 9 years ago
bugherder

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

	Carsten Book [:Tomcat]
	Comment 14 • 9 years ago
bugherder uplift

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