408898 - Drawing page with drawWindow duplicates flash content

Status: VERIFIED FIXED

(Core :: Graphics: Canvas2D, defect, P3)

Description

[Dave Townsend [:mossop]]

Attachment: screenshot

Don't know if this is us or flash, but when my extension does a drawWindow of a page with a flash movie in it suddenly a second image of the flash movie gets drawn upside-down at the bottom left of the firefox window. See the attachment.

The previous version of flash did not exhibit this, but that was quite old, I am now on 9r115.

Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; en-US; rv:1.9b3pre) Gecko/2007121804 Firefox/3.0b2pre ID:2007121804

Comment 1

[Dave Townsend [:mossop]]

Given the number of extensions around that use drawWindow I think we're going to find people hitting this a lot. We need to figure out if this is flash or us.

My attempts to make a simple testcase are currently being scuppered by bug 406334 unfortunately.

Comment 2

[Robert O'Callahan (:roc) (email my personal email if necessary)]

Josh, I bet this is Quartz drawing model stuff.

Comment 3

[Dave Townsend [:mossop]]

I suspect this is the same issue and not caused by drawWindow:

Visit http://www.samsung.com/uk/consumer/subtype/subtype.do?group=itbusiness&type=monitors&subtype=lcd
Hover over the menu links across the top of the page.

The flash content jumps around on the page.

Comment 4

[Robert O'Callahan (:roc) (email my personal email if necessary)]

Probably a dup of bug 395983

Comment 5

[Stephen Donner [:stephend] Not actively reading bugmail]

http://www.parkerpen.com/en/ too

Comment 6

[jag (Peter Annema)]

I see this and I'm pretty sure I don't have any extensions installed.

Comment 7

[Stephen Donner [:stephend] Not actively reading bugmail]

Dave: is this fixed for you now that bug 395983 has landed?

Comment 8

[Dave Townsend [:mossop]]

No this still seems to be a problem

Comment 9

[Robert O'Callahan (:roc) (email my personal email if necessary)]

I've actually seen a variant of this bug where the Flash object in a window actually appears upside down at the bottom of another window... looks bad :-). Probably related.

Comment 10

[Matthew Gregan [:kinetik]]

Attachment: patch v1

We need to call SetWindow in more cases.  I haven't worked out exactly which cases yet, so this patch calls SetWindow unconditionally in the CoreGraphics plugin paint path.  We know that we need to call SetWindow if BeginNativeDrawing gives us an off-screen CGContext, but there seem to be other cases we are missing such as those that are causing bug #419187.

I'll follow this patch up with a better one (where we call SetWindow only when necessary) soon, but I think we should get this simple fix in for beta 4.

Comment 11

[Matthew Gregan [:kinetik]]

Forgot to mention that calling SetWindow on each paint doesn't seem to have
negative side effects.  Plugin paint performance (with Flash) isn't obviously
affected (checked with some Flash that displays the current frame rate).

Comment 12

[jag (Peter Annema)]

Woot!

Comment 13

[Robert O'Callahan (:roc) (email my personal email if necessary)]

Checked in. I don't suppose there's a way to write a reftest for this?

Comment 14

[Dave Townsend [:mossop]]

Awesome, thanks!

Comment 15

[Jeff Walden [:Waldo]]

Don't think so, yet -- need bug 372352 fixed first.

Comment 16

[Dave Townsend [:mossop]]

Well that and drawWindow can't draw plugin content most of the time (bug 313462)