1561395 - Improve drawSnapshot API

Status: RESOLVED FIXED

(Core :: Graphics, enhancement, P3)

Description

[Ryan Hunt [:rhunt] (on leave until early May)]

• Expose it off of WindowGlobalParent so we can snapshot the whole browser window or just a specific remote iframe
• Allow specifying 'capture the whole viewport' instead of an explicit rect

Here's some sample code you can put in your browser console to test this out:

img = await docShell.browsingContext.currentWindowGlobal.drawSnapshot(null, 1, 'white');
canvas = document.createElement('canvas');
canvas.width = img.width;
canvas.height = img.height;
ctx = canvas.getContext('2d');
ctx.drawImage(img, 0, 0);
uri = canvas.toDataURL()

Comment 1

[Ryan Hunt [:rhunt] (on leave until early May)]

I would've liked to split this patch up into cleaner parts, but the logic is pretty tangled up. I hope it's still simple enough to be reviewed. At the least, no code is actively using or testing this so it's a low risk change.

Comment 2

[Ryan Hunt [:rhunt] (on leave until early May)]

Attachment: Bug 1561395 - Move drawSnapshot API to WindowGlobalParent and allow specifying the whole viewport as a rect. r?mattwoodrow,nika

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/09fcee21b246
Move drawSnapshot API to WindowGlobalParent and allow specifying the whole viewport as a rect. r=mattwoodrow,nika

Comment 4

[Arthur Iakab [arthur_iakab]]

https://hg.mozilla.org/mozilla-central/rev/09fcee21b246