514408 - improved plugin clipping

Status: RESOLVED FIXED

(Core Graveyard :: Widget: OS/2, defect)

Description

[Rich Walsh]

Attachment: implement plugin clipping windows

The current method for clipping plugin widgets by resizing their windows hasn't been as successful as expected because:
- plugin setup code resizes the widget's window after the OS/2 code has already clipped it, causing it to overlay other content until the first scroll occurs;
- some plugins (most notably, mplayer) ignore the dimensions passed to them by NPP_SetWindow() and resize their content based on the size of the widget's window.

The attached patch resolves these issues by implementing Kp Myung-hun's suggestion to use a separate window to do the clipping.  It inserts a PM window between the base page & the plugin widget, then alters the window's size and the widget's position within it to clip the widget as needed.

Comment 1

[Peter Weilbacher]

Comment on attachment 398370 [details] [diff] [review]
implement plugin clipping windows

I'm not yet sure if I understand the new functions correctly. One stupid question upfront: if there are several plugins on the same page do they all get the same mClipWnd assigned to them? The page is just one nsWindow instance now, right?

Comment 2

[Rich Walsh]

(In reply to comment #1)
> if there are several plugins on the same page do they all get the same
> mClipWnd assigned to them? The page is just one nsWindow instance now, right?

The page may be one nsWindow, but so is each plugin widget - and each one has its own clipping window stored in mClipWnd.  For nsWindows that aren't plugins, mClipWnd will be null.

If you have PMTree, you can see how the windows are arranged when you visit Heiko Nitzsche's GBM Demo page <http://heikon.home.tlink.de/frames/gbm_plugin_mozilla_test_embed.html>.  Drill down to the page's window and you'll see 12 'nsClipWnd' children.  Each of them will have a MozillaWindowClass child:  that's the plugin window it's clipping.

Comment 3

[Peter Weilbacher]

Comment on attachment 398370 [details] [diff] [review]
implement plugin clipping windows

Of course, thanks for the reminder. I think this change actually leads to more readable code. :-)

Comment 4

[Peter Weilbacher]

I'll try to fix my Hg setup to check this in, but this won't be quick. So maybe someone else can do it.

Comment 5

[Peter Weilbacher]

http://hg.mozilla.org/mozilla-central/rev/3bd7c1481a4a
http://hg.mozilla.org/releases/mozilla-1.9.2/rev/7b3519c07c35