Jonathan Wilde [:jwilde] Reporter
	Description • 11 years ago

When you pan the start UI, the richgrid will periodically disappear. See attached video.

	Brian R. Bondy [:bbondy]
	Comment 1 • 11 years ago

This is all changing with the async pan zoom controller, we should re-evaluate if this is a bug when that lands and is switched on.

	Jim Mathies [:jimm]
	Comment 3 • 11 years ago

I'm pretty sure this is in layers code. If we can assure ourselves it's not in the front end we should update the product/component so gfx folks see it.

jwilde, can you reproduce this in mc tip with "gfx.direct2d.disabled" set to true?

	Jonathan Wilde [:jwilde] Reporter
	Comment 4 • 11 years ago

Updated to mc tip and clobbered/rebuilt:

Without gfx.direct2d.disabled: flicker.
With gfx.direct2d.disabled: no flicker.

	Milan Sreckovic [:milan] (needinfo for best results)
	Comment 7 • 11 years ago

Bas, thoughts?

	Jim Mathies [:jimm]
	Comment 8 • 11 years ago

reproducible on this page:

https://developer.mozilla.org/en-US/docs/HTML/HTML_Elements/textarea#HTML_Content

down near the bottom where the page has an embedded iframe with a text area in it.

	Bas Schouten (:bas.schouten)
	Comment 9 • 11 years ago

(In reply to Milan Sreckovic [:milan] from comment #7)
> Bas, thoughts?

Hrm, I'm not sure what the behavior of Metro is at the moment with Direct2D disabled, definitely looks like a graphics problem but I have no initial idea on what the cause is. Also no Windows 8 machine with me in SF to try and debug this.

	Marco Mucci [:MarcoM]
	Comment 10 • 11 years ago

Hi Bas, we have Metro team members in SF who could show you on a Win 8 device.

	Bas Schouten (:bas.schouten)
	Comment 11 • 11 years ago

(In reply to Marco Mucci [:MarcoM] from comment #10)
> Hi Bas, we have Metro team members in SF who could show you on a Win 8
> device.

I'd be more than happy to look at it, I'm at the 7th floor on Elika's desk. I can probably give some pointers as well but I doubt I can do significant debugging right now.

	Marco Mucci [:MarcoM]
	Comment 12 • 11 years ago

Hi Ally, can you see Comments 9,10,11.

	Allison Naaktgeboren :ally
	Comment 13 • 11 years ago

Bas, headed your way

	Bas Schouten (:bas.schouten)
	Comment 14 • 11 years ago

Had a look at Ally's machine. ContentHostDoubleBuffered::UpdateThebes and ThebesLayerBuffer::BeginPaint is kind of where all the mess of moving the buffer around in memory and making sure front and back buffer are in sync happens. This bug looks to me like sometimes the syncing is not correct (i.e. the content in the middle, which is not being redrawn, is in one of the buffers but not in the other). It's particularly interesting that as you scroll it can re-appear, meaning it either gets redrawn or we're just ending up with 'the other' buffer of the swap chain where the content is still present.

	Marco Mucci [:MarcoM]
	Comment 15 • 11 years ago

Thanks for looking into it Bas.  Anything you can do to help you would great.

	Jim Mathies [:jimm]
	Comment 18 • 11 years ago

on latest tip (Wed Jul 24 05:36:15 2013 PDT), I can't reproduce.

	Jim Mathies [:jimm]
	Comment 19 • 11 years ago

Oddly enough, this is now back with apz enabled.

	Matt Brubeck (:mbrubeck) Assignee
	Comment 20 • 11 years ago

I'm also seeing this again with APZC disabled, though for a while it went away.

	juan becerra [:juanb]
	Comment 21 • 11 years ago

On machines with Atom processors the tiles disappear when you pan left or right.

	Brian R. Bondy [:bbondy]
	Comment 22 • 11 years ago

I get that sometime with my sony vaio which is intel

	Milan Sreckovic [:milan] (needinfo for best results)
	Comment 23 • 11 years ago

Does it work with the patch from bug 900742?

	Jim Mathies [:jimm]
	Comment 24 • 11 years ago

(In reply to Milan Sreckovic [:milan] from comment #23)
> Does it work with the patch from bug 900742?

Doesn't look like an event related patch like that would help but I can take it for a spin to see.

One interesting thing I noticed about this today, when we scroll via the mouse wheel we don't see a flicker. Mouse wheel translates into scrollBy calls on the start ui panel. Not sure why it would not reproduce in that case, but reproduce when dragging the scrollbar with the mouse to scroll.

	Matt Brubeck (:mbrubeck) Assignee
	Comment 25 • 11 years ago

I discovered today that removing the background image ("Firefox" watermark) from the start page fixes the flickering on my system.  Is this an acceptable band-aid until we can find a fix or workaround that lets us scroll correctly with the image in place?

	Yuan Wang(:Yuan) – Mobile Firefox Design Lead
	Comment 26 • 11 years ago

That's acceptable with me. The improved performance is definitely a bigger win here.

	Jim Mathies [:jimm]
	Comment 28 • 11 years ago

We should spin this patch off into a metro bug so the gfx bug stays open (or change up this bug and file a new gfx bug.) We still want a bug open on the compositor / layers painting problem. (I've seen this occasionally in content as well.)

	Brian R. Bondy [:bbondy]
	Comment 29 • 11 years ago

Let's spin a new gfx bug for that and CC kats, that issue will probably be one he, or BenWa has to fix. It would be ideal if we could use jing to capture a short video of the problem happening on content. It's just a software that you install, press a button to record your screen, and it gives you a link you can use online.

	Brian R. Bondy [:bbondy]
	Comment 30 • 11 years ago

Jim if you can reproduce that easily you can also try tweaking some of these prefs:
http://mxr.mozilla.org/mozilla-central/source/gfx/layers/ipc/AsyncPanZoomController.cpp#146

	Allison Naaktgeboren :ally
	Comment 31 • 11 years ago

Comment on attachment 786642 [details] [diff] [review]
work-around: remove "watermark" background image

Review of attachment 786642 [details] [diff] [review]:
-----------------------------------------------------------------

Does what it says on the box. Though I hope we get a real gfx fix soon. :)

	Matt Brubeck (:mbrubeck) Assignee
	Comment 32 • 11 years ago

https://hg.mozilla.org/integration/fx-team/rev/4e2e139c6b83

As discussed above, we'll close this bug and open a new bug to track the underlying graphics or layout issue.

	Ed Morley [:emorley]
	Comment 33 • 11 years ago

https://hg.mozilla.org/mozilla-central/rev/4e2e139c6b83

	Jim Mathies [:jimm]
	Comment 34 • 11 years ago

(In reply to Matt Brubeck (:mbrubeck) from comment #32)
> https://hg.mozilla.org/integration/fx-team/rev/4e2e139c6b83
> 
> As discussed above, we'll close this bug and open a new bug to track the
> underlying graphics or layout issue.

Did we file a new bug yet?

	Jim Mathies [:jimm]
	Comment 35 • 11 years ago

(In reply to Jim Mathies [:jimm] from comment #34)
> (In reply to Matt Brubeck (:mbrubeck) from comment #32)
> > https://hg.mozilla.org/integration/fx-team/rev/4e2e139c6b83
> > 
> > As discussed above, we'll close this bug and open a new bug to track the
> > underlying graphics or layout issue.
> 
> Did we file a new bug yet?

filed bug 903421.