1248398 - canvas2d clearRect ignores clipping region

Status: RESOLVED FIXED

(Core :: Graphics, defect, P3)

Description

[neil.morrison44]

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/48.0.2564.109 Safari/537.36

Steps to reproduce:

http://jsfiddle.net/wbf2930a/3/

within a canvas 2d context, begin a path, draw an arc, then clip(), clearRect an area containing the clipped region.

FireFox 44.0.2 on OSX El Capitan version 10.11.3


Actual results:

The entirety of the canvas will be cleared, not just the rect defined in clearRect.


Expected results:

The cleared area should have been limited to the clipped region.
(as happens in Chrome, Safari, IE etc)

Comment 1

[Tooru Fujisawa [:arai]]

Possibly same issue as bug 1248525.

it's already fixed in firefox 46, but firefox 44 and 45 are affected.

Regression range:
https://hg.mozilla.org/integration/mozilla-inbound/pushloghtml?fromchange=e5746165c704a82fc92d059ef9303562d6b3c886&tochange=5ed72fdd632767e03d6862efd10fc15a34256845

and fixed by bug 1082598:
https://hg.mozilla.org/integration/mozilla-inbound/pushloghtml?fromchange=d8e260e1535f0ff3877b21d6846380dedf449453&tochange=6630a176477ef903dcf3057db755abc43ba5018d

Comment 2

[u279076]

[Tracking Requested - why for this release]: regression from enabling SkiaGL on Mac OS X (bug 1150944) and fixed with a Skia update in Firefox 46. As highlighted in bug 1248525 this is probably too risky to uplift and the alternative is turning off SkiaGL in Beta/Release. The work around is to simply use Developer Edition.

Comment 3

[Sylvestre Ledru [:Sylvestre]]

Same as in bug 1248525

Comment 4

[Lee Salzman [:lsalzman]]

(In reply to Sylvestre Ledru [:sylvestre] from comment #3)
> Same as in bug 1248525

Noting here as well that I had looked into this. I could not manage to isolat ea simple fix to backport for this one from the Skia update. So I agree on waiting for 46 for the fix to come in.

Comment 5

[Thayne]

I have seen this in Firefox 44 and 45 with this simple use case: http://jsfiddle.net/6r63fan0/3/. It should show a red square with two overlapping white squares in the top left corner. But in firefox on two macs it just shows a white square. (but not on my linux machine).

the user agents and graphics cards for the machines I saw it on are below:

Mozilla/5.0 (Macintosh; Intel Mac OS X 10.10; rv:45.0) Gecko/20100101 Firefox/45.0
AMD Radeon HD 6750M 512 MB

Mozilla/5.0 (Macintosh; Intel Mac OS X 10.11; rv:44.0) Gecko/20100101 Firefox/44.0
Intel HD Graphics 5000 (1536 MB VRAM)

Comment 6

[Thayne]

A workaround that worked for me, is using globalCompositeOperation = 'destination-out' and using fillRect instead of clearRect.

Comment 7

[Lee Salzman [:lsalzman]]

Fixed since long ago in 46 with Skia update, and older branches than that are wontfix, so just closing this out.