1561003 - Support scaling rasterized content in OOP-iframes with webrender when ancestor remote browsers have transforms

Status: RESOLVED WORKSFORME

(Core :: Graphics: WebRender, enhancement, P3)

Description

[Ryan Hunt [:rhunt]]

If an OOP-iframe has rasterized content with webrender, we should scale it if it's under a transform in a different remote browser. This is supported for layers using EffectsInfo [1] [2].

[1] https://searchfox.org/mozilla-central/rev/928742d3ea30e0eb4a8622d260041564d81a8468/layout/generic/nsSubDocumentFrame.cpp#1420
[2] https://searchfox.org/mozilla-central/rev/928742d3ea30e0eb4a8622d260041564d81a8468/layout/painting/nsDisplayList.cpp#2882

Comment 1

[Liz Henry (:lizzard) (relman/hg->git project)]

Would this fix some of the regressions caused by bug 1558482?

Comment 2

[Ryan Hunt [:rhunt]]

No, but those regressions should be fixed by bug 1560272.

Comment 3

[Jonathan Watt [:jwatt]]

How far do we want to go with this. For CSS animations we try to evaluate the min/max scale that will be applied during an animation and use that to determine the size of surfaces under that transform.

Comment 4

[Matt Woodrow (:mattwoodrow)]

I don't think this is super important, since WebRender will be rasterizing most content on the compositor side, when all cross-process display items have been merged.

For non-WebRender this is much more important, but Ryan has implemented that already.

Comment 5

[Chris Peterson [:cpeterson]]

Tentatively moving all bugs whose summaries mention "Fission" (or other Fission-related keywords) but are not assigned to a Fission Milestone to the "?" triage milestone.

This will generate a lot of bugmail, so you can filter your bugmail for the following UUID and delete them en masse:

0ee3c76a-bc79-4eb2-8d12-05dc0b68e732

Comment 6

[Chris Peterson [:cpeterson]]

This is not a Fission MVP blocker.

Comment 7

[Glenn Watson [:gw]]

This is handled correctly by WR during scene builds.