635405 - Zooming windowless plugin frame can cause it to "bleed" outside bounds

Status: RESOLVED FIXED

(Core :: Layout, defect)

Description

[Chris Jones [:cjones] inactive; ni?/f?/r? if you need me]

STR
 (1) Load URL above
 (2) Ctrl-+ page to zoom in a ways
 (3) Ctrl-0

The plugin ImageLayer ends up drawing outside its bounds and splatting content all over its surrounding ThebesLayer.  Nothing knows to invalidate what was splatted, so it can persist "forever".

Not clear yet what's causing this; roc suggested empty transactions.  Wouldn't necessarily block on this, but it's a regression from 3.6.  Would be nice to fix.

Comment 1

[Chris Jones [:cjones] inactive; ni?/f?/r? if you need me]

(Can't attach a screenshot because that invalidate the entire window and makes the glitch go away.  But it's easy to repro.)

Comment 2

[Timothy Nikkel (:tnikkel)]

This could very well be the plugin version of bug 633164.

Comment 3

[Chris Jones [:cjones] inactive; ni?/f?/r? if you need me]

Yup, I'd take that bet.

Comment 4

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

It certainly meets softblocker criteria.

Comment 5

[Mats Palmgren (inactive)]

Attachment: wip

Fwiw, this seems to fix it.  Should we fall through here?
It's the nsDisplayPluginReadback that is causing the problem.

Comment 6

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

I don't see how that can possibly be right. We wouldn't paint anything when using async rendering.

Comment 7

[Mats Palmgren (inactive)]

Applying the patches in bug 631388 changes the symptoms in this bug.
Now the damage looks similar to what I saw in bug 633164, ie changing
the zoom doesn't invalidate the old area.

Comment 8

[Mats Palmgren (inactive)]

Attachment: fix v1

Detect image size change and then UnionRect the old area to the
damage so that it'll be Invalidated too.
Simplify the common "rect + TopLeft" expressions to make the code
more readable.

Comment 9

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

Comment on attachment 514336 [details] [diff] [review]
fix v1

Nice.

Comment 10

[Mats Palmgren (inactive)]

Needs bug 631388 though to work correctly, although I think it wouldn't
cause any problem if we landed it before that.

Comment 11

[Mats Palmgren (inactive)]

http://hg.mozilla.org/mozilla-central/rev/cdf6300f80f5