Bug 33081

Summary:	Bad Win32 Backend Performance After Fallback Change
Product:	cairo	Reporter:	Brent Fulgham <bfulgham>
Component:	win32 backend	Assignee:	cairo-bugs mailing list <cairo-bugs>
Status:	RESOLVED FIXED	QA Contact:	cairo-bugs mailing list <cairo-bugs>
Severity:	blocker
Priority:	medium	CC:	joeybubbabob
Version:	1.9.2
Hardware:	Other
OS:	Windows (All)
Whiteboard:
i915 platform:		i915 features:
Bug Depends on:
Bug Blocks:	44797

Description Brent Fulgham 2011-01-13 16:08:49 UTC

It turns out that the Mozilla project has been unable to use Cairo since the early part of 2010 due to a change cairo-surface-fallback.c.

(see "http://cgit.freedesktop.org/cairo/commit/?id=3b1c0a4bd66660780095e6016e3db451f34503a3")

While the commit message indicates that this would only impact the GL backend, it turns out that the win32 backend is heavily impacted by this change.

Ultimately, the correct resolution is to fix the win32 backend so that it does not need to use fallbacks.

Comment 1 Brent Fulgham 2011-05-02 09:15:31 UTC

Example code to reference during implementation:

1. gl: Add a simple spans renderer for stroke/fill:

http://cgit.freedesktop.org/~company/cairo/commit/?h=gl&id=1d11af083f5368c88032a33ff40d0e21c139db18

2. gl: Fix span renderer for unbounded spans

http://cgit.freedesktop.org/~company/cairo/commit/?h=gl&id=ef8fd1355ea03b8566ef31642b32133d3543e4e8

3. gl : Fix span renderer doing bad stuff for CLEAR and SOURCE

http://cgit.freedesktop.org/~company/cairo/commit/?h=gl&id=7d8359721b581845260c0442a174e48b061484a7

Comment 2 Chris Wilson 2012-02-15 06:44:05 UTC

commit ae3319890eacd1c8282ca6df7b263ac74abb5f8d
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Sun Feb 12 11:25:07 2012 +0000

    win32: Rebase on the new compositor infrastructure
    
    Try and undo all the damage that has acrued over the years by plugging
    into the compositor pipeline.
    
    References: https://bugs.freedesktop.org/show_bug.cgi?id=42739
    References: https://bugs.freedesktop.org/show_bug.cgi?id=42821
    References: https://bugs.freedesktop.org/show_bug.cgi?id=33081
    Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

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