578511 - Aero Peek needs an API from Canvas to disable sync decoding of images

Status: RESOLVED FIXED

(Core :: Graphics: Canvas2D, defect)

Description

[Bobby Holley (:bholley)]

Canvas drawImage calls RenderDocument:
http://mxr.mozilla.org/mozilla-central/source/content/canvas/src/nsCanvasRenderingContext2D.cpp#3675

RenderDocument forces sync decoding on all drawn images, which will take effect when image discarding is switched back on (bug 563088):
http://mxr.mozilla.org/mozilla-central/source/layout/base/nsPresShell.cpp#5290

Unfortunately, this will slow down Aero Peek, because it has to sync decode the images for 20 pages. We want to let those images show up and render asynchronously.

Comment 1

[Bobby Holley (:bholley)]

Attachment: flag patch v1

Added a patch to make the flag available. Pushed to try as aa413bf0b2e0, and flagging roc for review.

Rob - Can you whip up a quick aero-peek patch to add this flag in the right place?

Comment 2

[Bobby Holley (:bholley)]

this looks green on try.

Comment 3

[Bobby Holley (:bholley)]

Comment on attachment 458108 [details] [diff] [review]
flag patch v1

oh hm I guess this needs sr too. Flagging vlad.

Comment 4

[Bobby Holley (:bholley)]

This blocks turning discarding back on (bug 563088), which is a blocker. Nominating.

Comment 5

[Rob Arnold [:robarnold]]

Attachment: Aero Peek frontend bits

Here's the frontend bits. Pop is clearly seen when loading the thumbnails. Not going to be seen for the live previews since we cache the thumbnail at full size and use it for the live preview.

Comment 6

[Bobby Holley (:bholley)]

Pushed to mozilla-central:
http://hg.mozilla.org/mozilla-central/rev/ac9dca1f6260
http://hg.mozilla.org/mozilla-central/rev/2e3fbf618f08

Resolving fixed.