Closed Bug 694140 Opened 8 years ago Closed 8 years ago

With GL layers, panning/zooming causes corruption and wrong colours on Fennec


(Core :: Graphics, defect)

Not set





(Reporter: ajuma, Assigned: romaxa)



(Keywords: regression)


(3 files, 2 obsolete files)

When zoomed in and then repeatedly zooming in and out while panning at the same time, I'm seeing a mix of content at different zoom levels, and incorrect colours (e.g. red becoming blue). This is happening both on a Nexus S and on a Galaxy Tab.

The amount of zooming and panning needed to see these problems varies, even on the same page -- sometimes it's right away, and other times it requires a bit longer (no more than a minute though).

This is a regression. Range:
This turns out to be a regression caused by the landing of Bug 690469.
Blocks: 690469
This looks like readback from front to back buffers is being messed up.
Ok, problem here is that PaintThebes, BasicThebesBuffer::BeginPaint assume that all buffer operations are finished and buffer is the all the time same (no double-buffering)... and calling SyncBackAndFront just in the beginning of PaintThebes not enough..

I need to think more about fixing that problem with ThebesLayerBuffer, will try to find better place for SyncBackAndFront...
Here is minor fix which does not revert whole Thebes Swap rework, but just making Buffers in sync right after Swap.
Attachment #566922 - Flags: feedback?(ajuma)
Attachment #566922 - Attachment is obsolete: true
Attachment #566922 - Flags: feedback?(ajuma)
Attachment #566927 - Flags: review?(ajuma)
Comment on attachment 566927 [details] [diff] [review]
Disable lazy backBuffer sync for SingleBuffer mode

This fixes the corruption caused by panning/zooming, but not the colour problem.

Please change the commit message to say what the patch does. 

Also, when this lands, we should keep the bug open while we find the real cause (and deal with the colour issue).
Attachment #566927 - Flags: review?(ajuma) → review+
Ok, I found what is the problem with thebes layers...
with static front we had front destroyed when backBuffer content type changed... but now we only do that when size is changed...
BackingSurface with locking handle it because we handle properly composition form surface to texture with different format types... but 
GLContext::UploadSurfaceToTexture cannot do that... (another bug?)
Ok, ehre is fix for color problem, we should check if new surface and current texture have equal format
Assignee: nobody → romaxa
Attachment #566927 - Attachment is obsolete: true
Attachment #566965 - Flags: review?(jones.chris.g)
(In reply to Oleg Romashin (:romaxa) from comment #9)
> Created attachment 566965 [details] [diff] [review] [diff] [details] [review]
> Fixed color problem

This patch does indeed fix both problems for me.
Attachment #566965 - Flags: review?(ajuma)
Attachment #566965 - Flags: review?(ajuma) → review+
Attachment #566965 - Flags: review?(jones.chris.g) → review+
Keywords: checkin-needed
In my queue with a few other bits that are being sent to try first and then onto inbound :-)
Keywords: checkin-needed
Closed: 8 years ago
Resolution: --- → FIXED
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