Bug 57388

Summary:

Need a way to specify that a ShareableBitmap has no alpha channel

Product:

WebKit

Reporter:

Adam Roben (:aroben) <aroben>

Component:

Platform

Assignee:

Nobody <webkit-unassigned>

Status:

RESOLVED FIXED

Severity:

Normal

CC:

andersca

Priority:

Version:

528+ (Nightly build)

Hardware:

All

OS:

All

Bug Depends on:

57397

Bug Blocks:

45567

Attachments:

Description	Flags
Add a way to specify that a ShareableBitmap has no alpha channel	andersca: review+

Description Adam Roben (:aroben) 2011-03-29 14:13:44 PDT

ShareableBitmap currently always honors the alpha channel of its underlying data. This doesn't work well for use with APIs like GDI, which don't support alpha channels. (See bug 45567 comment 17 for one specific bug that this causes.)

We should have a way of specifying that a particular ShareableBitmap doesn't have an alpha channel.

Comment 1 Adam Roben (:aroben) 2011-03-29 14:15:38 PDT

In theory, this should make blitting into the window's backing store faster on Windows, since CG will be able to ignore the alpha channel entirely.

Comment 2 Adam Roben (:aroben) 2011-03-29 16:14:24 PDT

Created attachment 87426 [details]
Add a way to specify that a ShareableBitmap has no alpha channel

Comment 3 Adam Roben (:aroben) 2011-03-30 07:43:41 PDT

Committed r82442: <http://trac.webkit.org/changeset/82442>

Comment 4 Adam Roben (:aroben) 2011-03-30 08:08:06 PDT

Mac build fix

Committed r82445: <http://trac.webkit.org/changeset/82445>