1920580 - Add plumbing to allow compositor process to context reset individual canvases

Status: RESOLVED FIXED

(Core :: Graphics: Canvas2D, task)

Description

[Andrew Osmond [:aosmond] (he/him)]

We support context lost/restored for Canvas2D, but only for GPU process crashes. We should extend this to work for WebGL context resets with accelerated canvas. This will allow us to recover from a lost context in the case where we did not happen to have a snapshot saved already.

Comment 1

[Andrew Osmond [:aosmond] (he/him)]

Attachment: Bug 1920580 - Add plumbing to allow compositor process to context reset individual canvases.

This patch adds the necessary plumbing for accelerated canvas to trigger
a context lost / context restored events on the Canvas2D DOM object.
Currently we support this when the GPU process is crashed and restored,
but accelerated canvas can lose its WebGL context in a similar manner.

Note that not all accelerated canvases are impacted. Only the ones
without a recent snapshot and/or already fallen back to Skia will
require a context lost / restored event.

Comment 2

[Lee Salzman [:lsalzman]]

Attachment: Bug 1920580 - Detect WebGL context loss and notify Canvas2D of reset. r?aosmond

When AC2D fails to fall back to a software canvas due to not having a cached
surface available, we need to notify the canvas with an event so that it can
respond appropriately. This uses the newly added plumbing to do route this.

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/5287a74aad56
Add plumbing to allow compositor process to context reset individual canvases. r=lsalzman
https://hg.mozilla.org/integration/autoland/rev/2cb15593fa88
Detect WebGL context loss and notify Canvas2D of reset. r=aosmond

Comment 4

[agoloman]

https://hg.mozilla.org/mozilla-central/rev/5287a74aad56
https://hg.mozilla.org/mozilla-central/rev/2cb15593fa88