727966 - MAPLE triggers 4 paints on a rotation

Status: RESOLVED FIXED

(Firefox for Android Graveyard :: General, defect, P2)

Description

[Kartikaya Gupta (email:[e-mail])]

1. Load about:firefox and wait for it to settle

2. Run:
adb logcat -c; adb logcat -v time | grep "Basic layers drawing"

3. Rotate phone

Comment 1

[Kartikaya Gupta (email:[e-mail])]

Oh, expected results: only one instance of "Basic layers drawing" should be printed; actual results: 4 are printed.

Comment 2

[(no longer active)]

This needs to be retested after my viewport fixes.  Specifically I pause painting for some time during rotation, so that might have improved the situation.

Comment 3

[Kartikaya Gupta (email:[e-mail])]

Just an update: we're still doing 2 draws during rotation. The first one is sometimes glitchy, and should be eliminated, but I want to fix bug 729653 first as it will remove some of the complicatedness of the code.

Comment 4

[Kartikaya Gupta (email:[e-mail])]

Attachment: Don't do unnecessary repaint on SIZE_CHANGED event

The NS_SIZE event that gets sent to gecko in the nsWindow::OnSizeChanged function seems sufficient to let layout know that things have changed and need redrawing.

I've pushed this change to try at https://tbpl.mozilla.org/?tree=Try&rev=9545d9d6f157 to make sure it doesn't break XUL since this is shared code.

Comment 6

[Kartikaya Gupta (email:[e-mail])]

https://hg.mozilla.org/integration/mozilla-inbound/rev/6ea259121f1e

On simple pages we now do only one draw on rotation, and it should be glitch-free.

Comment 7

[Marco Bonardo [:mak]]

https://hg.mozilla.org/mozilla-central/rev/6ea259121f1e