1851585 - Remove nsWindow::mPaintDC.

Status: RESOLVED FIXED

(Core :: Widget: Win32, task)

Comment 1

[Emilio Cobos Álvarez [:emilio]]

Attachment: Bug 1851585 - Remove nsWindow::mPaintDC. r=#win-reviewers

It's unused.

Comment 2

[Emilio Cobos Álvarez [:emilio]]

Attachment: Bug 1851585 - Minor clean-ups in nsWindow::OnPaint. r=#win-reviewers

Comment 3

[Emilio Cobos Álvarez [:emilio]]

Attachment: Bug 1851585 - Don't deal with WM_PRINTCLIENT. r=#win-reviewers

There's no real reason to do this, and other browsers don't either. This
is in preparation for further simplifications to how we deal with
transparent windows (because they're now pretty broken,
see bug 1850979).

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/092f81f39e6a
Remove nsWindow::mPaintDC. r=win-reviewers,gstoll

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/ab71e5c57a38
Minor clean-ups in nsWindow::OnPaint. r=win-reviewers,gstoll

Comment 6

[Cosmin Sabou [:CosminS]]

https://hg.mozilla.org/mozilla-central/rev/092f81f39e6a
https://hg.mozilla.org/mozilla-central/rev/ab71e5c57a38

Comment 7

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/bcda86efab04
Don't deal with WM_PRINTCLIENT. r=win-reviewers,rkraesig

Comment 8

[Narcis Beleuzu [:NarcisB]]

https://hg.mozilla.org/mozilla-central/rev/bcda86efab04

Comment 9

[Masatoshi Kimura [:emk]]

External apps may use WM_PRINT/WM_PRINTCLIENT to take a screenshot of our windows. I don't think we can remove the WM_PRINTCLIENT handler based on our internal usage.

Comment 10

[Emilio Cobos Álvarez [:emilio]]

(In reply to Masatoshi Kimura [:emk] from comment #9)

External apps may use WM_PRINT/WM_PRINTCLIENT to take a screenshot of our windows. I don't think we can remove the WM_PRINTCLIENT handler based on our internal usage.

Can you elaborate? We don't paint synchronously so how does that work exactly? Why do other apps not need it? MSDN says that windows such as controls need to implement it, and that some APIs like AnimateWindow need it, but it doesn't say anything else and we're neither afaict.

Comment 11

[Masatoshi Kimura [:emk]]

Sorry, I was wrong.

• Cross-process ::SendMessage(WM_PRINT(CLIENT)) does not work.
• ::PrintWindow() uses WM_PAINT instead of WM_PRINT(CLIENT) contrary to the documentation.

So external apps have no way to use the WM_PRINTCLIENT handler of Firefox.

Comment 12

[Emilio Cobos Álvarez [:emilio]]

Cool, thanks for checking tho, and for the answer! (you're definitely more familiar with all this stuff than me).