bryce at kemper.freedesktop.org
Tue Sep 23 16:42:41 PDT 2014
NEWS | 48 +++++++++++++++++++++++++++---------------------
1 file changed, 27 insertions(+), 21 deletions(-)
Author: Bryce Harrington <bryce at osg.samsung.com>
Date: Tue Sep 23 16:41:36 2014 -0700
NEWS: Revise downscaling feature description
Updated feature description using text from Bill. Also updated bugfix
list to include recent fixes.
diff --git a/NEWS b/NEWS
index 1f6e1f5..01e56de 100644
@@ -15,27 +15,26 @@ the image backend and by other backends as needed for fallbacks.
- Use Pixman's convolution filters for image downscaling, such as for
- raster images in Inkscape SVG documents. This improves image quality
- when viewing large images on low resolution devices, as firefox and
- chromium already do.
- Filter generator:
- - Single filter, no "reconstruction" and "sample" filter
- - Filters for derivative < 1 work
- - Fixed IMPULSE and BOX
- - Added TENT, CATMULL_ROM, NOTCH. Remove LANZCOS2.
- - Renamed CUBIC to MITCHELL
- Cairo's filter settings:
- - CAIRO_FILTER_GOOD: uses BOX filter for scales less than .75 in
- either direction. Uses PIXMAN_FILTER_GOOD (ie BILINEAR) otherwise.
- - CAIRO_FILTER_BEST: uses CATMULL filter always. Upscaling more than
- 2x will produce anti-aliased square pixels, similar to OS/X.
- - CAIRO_FILTER_GAUSSIAN: this obsolete value is used to test other
- filters. The program must declare and poke the filter into the
- static variable ikernel. This should be removed for production
+ Filtering improvements for the image backend, in particular
+ down-scaling of images produces filtered images that depend on all the
+ pixels of the source. When using the image backend you get the
+ following settings:
+ CAIRO_FILTER_GOOD: uses a box filter for scales less than .75 in
+ either direction. For scales larger than this, the same filter as
+ CAIRO_FILTER_BILINEAR is used.
+ CAIRO_FILTER_BEST: uses a Catmull-Rom filter always. When upscaling
+ more than 2x this will produce anti-aliased square pixels, similar
+ to OS/X.
+ CAIRO_FILTER_GAUSSIAN: uses PIXMAN_FILTER_BEST, which in current
+ pixman is the same as BILINEAR. (This is subject to change in the
+ Note that other backends, in particular xlib/xcb, do not implement
+ these filtering fixes yet, however other actions may cause them to use
+ an image fallback which will cause these filters to be used.
Improve handling of device transformation and scaling, allowing Cairo
to now support scaling at a device level, permitting easier, more
@@ -58,6 +57,9 @@ Features
seems to have caused much trouble for unclear benefit, and most
distros are reverting or disabling it anyway.
+ Optimize VBO size on GL to 1M and to 16k for EGL. This improves
+ (theoretical) performance for desktop GLX use cases while avoiding
+ hitting VBO memory size limitations on embedded devices.
@@ -169,6 +171,10 @@ Bug fixes
Fix image scale on Win32 when GDI scale is not identity.
+ Fix float endian configure test when using clang -O4
+ Fix compilation with Android bionic libc
Various cleanups and fixes to warnings, documentation, tests, and
build system. Improve error handling and return value checks.
Cleanup XFAIL tests and reference images. Cover recently added
More information about the cairo-commit