path: root/NEWS

Snapshot 1.3.10 (2006-12-23 Carl Worth <cworth@cworth.org>)
===========================================================
Santa Claus is coming just a little bit early this year, and he's
bringing a shiny new cairo snapshot for all the good little boys and
girls to play with.

This is the fifth development snapshot in the 1.3 series. It comes 9
days after the 1.3.8 snapshot, and still well within our goal of
having a new snapshot every week, (though don't expect one next
week---we'll all be too stuffed with sugar plums).

Speaking of sugar plums, there's a sweet treat waiting in this cairo
snapshot---greatly improved performance for stroking rectilinear
shapes, like the ever common rectangle:

image-rgb          box-outline-stroke-100 0.18 -> 0.01: 25.58x speedup
████████████████████████▋
image-rgba         box-outline-stroke-100 0.18 -> 0.01: 25.57x speedup
████████████████████████▋
xlib-rgb          box-outline-stroke-100 0.49 -> 0.06:  8.67x speedup
███████▋
xlib-rgba         box-outline-stroke-100 0.22 -> 0.04:  5.39x speedup
████▍

In past releases of cairo, some people had noticed that using
cairo_stroke to draw rectilinear shapes could be awfully slow. Many
people had worked around this by using cairo_fill with a more complex
path and gotten a 5-15x performance benefit from that.

If you're one of those people, please rip that workaround out, as now
the more natural use of cairo_stroke should be 1.2-2x faster than the
unnatural use of cairo_fill.

And if you hadn't ever implemented that workaround, then you just
might get to see your stroked rectangles now get drawn 5-25x faster.

Beyond that performance fix, there are a handful of bug fixes in this
snapshot:

 * Fix for glyph cache race condition in glitz backend (Jinghua Luo)

 * Many fixes for ATSUI text rendering (Brian Ewins)

 * Un-break recent optimization-triggered regression in rendering text
   with a translation in the font matrix (Behdad Esfahbod)

 * Fix make check to work on OPD platforms (IA64 or PPC64)
   (Frederic Crozat)

 * Fix a couple of character spacing issues on Windows
    (Jonathan Watt)

Have fun with that, everybody, and we'll be back for more in the new
year, (with a plan to add the last of our performance improvements in
this round, fix a few bad, lingering bugs, and then finish off a nice,
stable 1.4 release before the end of January).

-Carl

Snapshot 1.3.8 (2006-12-14 Carl Worth <cworth@cworth.org>)
==========================================================
This is the fourth development snapshot in the 1.3 series. It comes
just slightly more than one week after the 1.3.6 snapshot.

After the bug fixes in 1.3.6, we're back to our original program of
weekly snapshots, each one faster than the one from the week
before. Cairo 1.3.8 brings a 2x improvement in the speed of rendering
linear gradients (thanks to David Turner), and a significant reduction
in X traffic when rendering text (thanks to Xan Lopez and Behdad
Esfahbod), making cairo behave very much like Xft does.

A few other things in the 1.3.8 snapshot worth noting include a more
forgiving image comparator in the test suite, (using the "perceptual
diff" metric and GPL implementation by Hector Yee[*]), a bug fix for
broken linking on x86_64 (thanks to M Joonas Pihlaja) and an even
better implementation of _cairo_lround, (not faster, but supporting a
more complete input range), from Daniel Amelang.

[*] http://pdiff.sourceforge.net/

Snapshot 1.3.6 (2006-12-06 Carl Worth <cworth@cworth.org>)
==========================================================
This is the third development snapshot in the 1.3 series. It comes two
weeks after the 1.3.4 snapshot.

We don't have fancy performance charts this week as the primary
changes in this snapshot are bug fixes. The performance work continues
and the next snapshot (planned for one week from today) should include
several improvements. The bug fixes in this snapshot include:

 * Fix undesirable rounding in glyph positioning (Dan Amelang)

   This bug was noticed by several users, most commonly by seeing
   improper text spacing or scrambled glyphs as drawn by nautilus. For
   example:

	Update to cairo-1.3.4 worsen font rendering
	https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=217819

 * Fix reduced range of valid input coordinates to tessellator
   (M Joonas Pihlaja)

   This bug was causing lots of assertion failures in mozilla as
   mentioned here:

	CAIRO_BO_GUARD_BITS and coordinate space?
	http://lists.freedesktop.org/archives/cairo/2006-December/008743.html

 * Fix several regressions in new tessellator (M Joonas Pihlaja)

   Joonas just had a good eye for detail here. I don't think any
   external cairo users had noticed any of these bugs yet.

 * Fix compilation problems of cairo "wideint" code on some platforms
   (Mathieu Lacage)

 * Fix failed configure due to broken grep (Dan Amelang)

   This bug was reported here:

	AX_C_FLOAT_WORDS_BIGENDIAN doesn't work because grep doesn't
	work with binary file
	https://bugs.freedesktop.org/show_bug.cgi?id=9124

 * Remove the pkg-config minimum version requirement (Behdad Esfahbod)

   Some systems ship with pkg-config 0.15 and there was really no good
   reason for cairo to insist on having version 0.19 before it would
   build.

There is also one new (but inert) feature in this snapshot. There's a
new option that can be passed to cairo's configure script:

	--disable-some-floating-point

	Disable certain code paths that rely heavily on double precision
	floating-point calculation. This option can improve
	performance on systems without a double precision floating-point
	unit, but might degrade performance on those that do.

As of this snapshot, this option does not make any change to cairo,
but it is possible that future versions of cairo will respect this
option and change the implementation of various functions as
appropriate.

Snapshot 1.3.4 (2006-11-22 Carl Worth <cworth@cworth.org>)
==========================================================
This is the second development snapshot in the 1.3 series. It comes
one week after the 1.3.2 snapshot.

This snapshot has a couple of significant performance improvements,
and also adds new support for producing multi-page SVG output, (when
targeting SVG 1.2)---thanks to Emmanuel Pacaud. The details of the
performance improvements are as follows:

1. The long-awaited "new tessellator".

   The credit for this being an improvement goes to Joonas Pihlaja. He
   took my really slow code and really put it through its paces to get
   the dramatic performance improvement seen below (up to 38x faster
   on realistic cases, and more than 10x faster for the zrusin_another
   test).

   His own writeup of the work he did is quite thorough, but more than
   can be quoted here. Please see his post for the interesting details:

   http://lists.freedesktop.org/archives/cairo/2006-November/008483.html

   (Though note that this snapshot also includes some additional,
   significant improvements that were only sketched out in that
   email---see "Generating fewer trapezoids").

2. More floating-point improvements

   Daniel Amelang continues to work the magic he began in the 1.3.2
   snapshot. This time he short-circuits floating-point
   transformations by identity matrices and applies the earlier
   floating-to-fixed-point technique to the problem of rounding.

   The improvements here will primarily benefit text performance, and
   will benefit platforms without hardware floating-point more than
   those that have it, (some text tests show 20% improvement on an x86
   machine and closer to 80% improvement on arm).

The performance chart comparing 1.3.2 to 1.3.4 really speaks for
itself, (this is on an x86 laptop). This is quite a lot of progress
for one week:

 xlib-rgb    stroke_similar_rgba_over-256   74.99 1.45% ->   2.03 68.38%: 36.86x speedup
███████████████████████████████████▉
 xlib-rgb  stroke_similar_rgba_source-256   78.23 1.43% ->   3.30 67.05%: 23.71x speedup
██████████████████████▊
 xlib-rgba             tessellate-256-100  820.42 0.15% ->  35.06 2.84%: 23.40x speedup
██████████████████████▍
image-rgba             tessellate-256-100  819.55 0.32% ->  35.04 3.56%: 23.39x speedup
██████████████████████▍
 xlib-rgb      stroke_image_rgba_over-256   78.10 1.43% ->   4.33 65.56%: 18.04x speedup
█████████████████
 xlib-rgb    stroke_image_rgba_source-256   80.11 1.63% ->   5.75 63.99%: 13.94x speedup
█████████████
 xlib-rgba  zrusin_another_tessellate-415   89.22 0.35% ->   8.38 5.23%: 10.65x speedup
█████████▋
image-rgba  zrusin_another_tessellate-415   87.38 0.89% ->   8.37 5.22%: 10.44x speedup
█████████▍
image-rgba        zrusin_another_fill-415  117.67 1.34% ->  12.88 2.77%:  9.14x speedup
████████▏
 xlib-rgba        zrusin_another_fill-415  140.52 1.57% ->  15.79 2.88%:  8.90x speedup
███████▉
image-rgba              tessellate-64-100    9.68 3.42% ->   1.42 0.60%:  6.82x speedup
█████▉
 xlib-rgba              tessellate-64-100    9.78 4.35% ->   1.45 0.83%:  6.72x speedup
█████▊
 xlib-rgb     stroke_linear_rgba_over-256   46.01 2.44% ->   7.74 54.51%:  5.94x speedup
█████
 xlib-rgb   stroke_linear_rgba_source-256   48.09 2.15% ->   9.14 53.00%:  5.26x speedup
████▎
 xlib-rgb     stroke_radial_rgba_over-256   50.96 2.34% ->  12.46 47.99%:  4.09x speedup
███▏
 xlib-rgb   stroke_radial_rgba_source-256   53.06 1.57% ->  13.96 46.57%:  3.80x speedup
██▊
image-rgba  paint_similar_rgba_source-256    0.12 1.57% ->   0.08 9.92%:  1.42x speedup
▍
image-rgba    paint_image_rgba_source-256    0.12 2.49% ->   0.08 10.70%:  1.41x speedup
▍
image-rgba                  world_map-800  356.28 0.46% -> 275.72 1.15%:  1.29x speedup
▎
 xlib-rgba                  world_map-800  456.81 0.39% -> 357.95 1.39%:  1.28x speedup
▎
image-rgb               tessellate-16-100    0.09 0.57% ->   0.07 3.43%:  1.23x speedup
▎
image-rgba              tessellate-16-100    0.09 0.06% ->   0.07 2.46%:  1.23x speedup
▎
image-rgba        text_solid_rgb_over-256    5.39 4.01% ->   4.47 0.70%:  1.21x speedup
▎
image-rgba       text_solid_rgba_over-256    5.37 0.82% ->   4.45 0.75%:  1.21x speedup
▎
image-rgba        text_image_rgb_over-64     0.78 0.10% ->   0.65 0.74%:  1.20x speedup
▎
image-rgba       text_image_rgba_over-64     0.78 0.29% ->   0.65 0.68%:  1.19x speedup
▎
image-rgb         text_solid_rgb_over-64     0.76 2.45% ->   0.63 0.81%:  1.19x speedup
▎
image-rgba       text_solid_rgba_over-64     0.76 0.33% ->   0.64 0.66%:  1.19x speedup
▎
image-rgba     text_similar_rgba_over-256    5.99 4.72% ->   5.04 1.09%:  1.19x speedup
▎

We should point out that there is some potential for slowdown in this
snapshot. The following are the worst slowdowns reported by the cairo
performance suite when comparing 1.3.2 to 1.3.4:

image-rgba              subimage_copy-256    0.01 0.87% ->   0.01 3.61%:  1.45x slowdown
▌
 xlib-rgb        paint_solid_rgb_over-256    0.31 10.23% ->   0.38 0.33%:  1.26x slowdown
▎
image-rgba           box-outline-fill-100    0.01 0.30% ->   0.01 2.52%:  1.21x slowdown
▎
image-rgba        fill_solid_rgb_over-64     0.20 1.22% ->   0.22 1.59%:  1.12x slowdown
▏
image-rgb       fill_similar_rgb_over-64     0.21 1.04% ->   0.24 1.06%:  1.11x slowdown
▏
image-rgba        fill_image_rgb_over-64     0.21 1.19% ->   0.24 0.72%:  1.11x slowdown
▏
image-rgba      fill_similar_rgb_over-64     0.21 0.18% ->   0.24 0.30%:  1.11x slowdown
▏
image-rgb        fill_solid_rgba_over-64     0.22 1.66% ->   0.24 1.15%:  1.11x slowdown
▏
image-rgb         fill_image_rgb_over-64     0.21 0.14% ->   0.24 0.80%:  1.11x slowdown
▏
image-rgba       fill_image_rgba_over-64     0.22 1.34% ->   0.25 0.20%:  1.11x slowdown
▏
image-rgba       fill_solid_rgba_over-64     0.22 1.48% ->   0.24 0.95%:  1.11x slowdown
▏
image-rgb      fill_similar_rgba_over-64     0.22 1.13% ->   0.25 1.25%:  1.10x slowdown
▏

The 45% slowdown for subimage_copy is an extreme case. It's unlikely
to hit many applications unless they often use cairo_rectangle;
cairo_fill to copy a single pixel at a time. In any case, it shows a
worst-case impact of the overhead of the new tessellator. The other
slowdowns (~ 10%) are probably more realistic, and still very
concerning.

We will work to ensure that performance regressions like these are not
present from one major release of cairo to the next, (for example,
from 1.2 to 1.4).

But we're putting this 1.3.4 snapshot out there now, even with this
potential slowdown so that people can experiment with it. If you've
got complex geometry, we hope you will see some benefit from the new
tessellator. If you've got primarily simple geometry, we hope things
won't slowdown too much, but please let us know what slowdown you see,
if any, so we can calibrate our performance suite against real-world
impacts.

Thanks, and have fun with cairo!

Snapshot 1.3.2 (2006-11-14 Carl Worth <cworth@cworth.org>)
==========================================================
This is the first development snapshot since the 1.2 stable series
branched off shortly after the 1.2.4 release in August 2006.

This snapshot includes all the bug fixes from the 1.2.6 release,
(since they originated here on the 1.3 branch first and were
cherry-picked over to 1.2). But more importantly, it contains some new
API in preparation for a future 1.4 release, and most importantly, it
contains several performance improvements.

The bug fixes will not be reviewed here, as most of them are already
described in the 1.2.6 release notes. But details for the new API and
some performance improvements are included here.

As with all snapshots, this is experimental code, and the new API
added here is still experimental and is not guaranteed to appear
unchanged in any future release of cairo.

API additions
-------------
Several new API additions are available in this release. There is a
common theme among all the additions in that they allow cairo to
advertise information about its state that it was refusing to
volunteer earlier. So this isn't groundbreaking new functionality, but
it is essential for easily achieving several tasks.

The new functions can be divided into three categories:

	Getting information about the current clip region
	-------------------------------------------------
	cairo_clip_extents
	cairo_copy_clip_rectangles
	cairo_rectangle_list_destroy

	Getting information about the current dash setting
	--------------------------------------------------
	cairo_get_dash_count
	cairo_get_dash

	Getting information from a pattern
	----------------------------------
	cairo_pattern_get_rgba
	cairo_pattern_get_surface
	cairo_pattern_get_color_stop_rgba
	cairo_pattern_get_color_stop_count
	cairo_pattern_get_linear_points
	cairo_pattern_get_radial_circles

In each of these areas, we have new API for providing a list of
uniform values from cairo. The closest thing we had to this before was
cairo_copy_path, (which is rather unique in providing a list of
non-uniform data).

The copy_clip_rectangles/rectangle_list_destroy functions follow a
style similar to that of cairo_copy_path. Meanwhile, the dash and
pattern color stop functions introduce a new style in which there is a
single call to return the number of elements available (get_dash_count
and get_color_stop_count) and then a function to be called once to get
each element (get_dash and get_color_stop_rgba).

I'm interested in hearing feedback from users of these new API
functions, particularly from people writing language bindings. One
open question is whether the clip "getter" functionality should adopt
a style similar to that of the new dash and color_stop interfaces.

API deprecation
---------------
The CAIRO_FORMAT_RGB16_565 enum value has been deprecated. It never
worked as a format value for cairo_image_surface_create, and it wasn't
necessary for supporting 16-bit 565 X server visuals.

XCB backend changes
-------------------
The XCB backend has been updated to track the latest XCB API (which
recently had a 1.0 release).

New quartz backend
------------------
Vladimir Vukicevic has written a new "native quartz" backend which
will eventually replace the current "image-surface wrapping" quartz
backend. For now, both backends are available, (the old one is
"quartz" and the new one is "nquartz"). But it is anticipated that the
new backend will replace the old one and take on the "quartz" name
before this backend is marked as supported in a release of cairo.

New OS/2 backend
----------------
Doodle and Peter Weilbacher have contributed a new, experimental
backend for using cairo on OS/2 systems.

Performance improvements
------------------------
Here are some highlights from cairo's performance suite showing
improvements from cairo 1.2.6 to cairo 1.3.2. The command used to
generate this data is:

	./cairo-perf-diff 1.2.6 HEAD

available in the perf/ directory of a recent checkout of cairo's
source, (the cairo-perf-diff script does require a git checkout and
will not work from a tar file---though ./cairo-perf can still be used
to generate a single report there and ./cairo-perf-diff-files can be
used to compare two reports).

Results are described below both for an x86 laptop (with an old Radeon
video card, recent X.org build, XAA, free software drivers), as well
as for a Nokia 770. First the x86 results with comments on each, (all
times are reported in milliseconds).

Copying subsets of an image surface to an xlib surface (much faster)
--------------------------------------------------------------------
 xlib-rgba              subimage_copy-512   10.50 ->   : 53.97x speedup
█████████████████████████████████████████████████████

Thanks to Christopher (Monty) Montgomery for this big performance
improvement. Any application which has a large image surface and is
copying small pieces of it at a time to an xlib surface, (imagine an
application that loads a single image containing all the "sprites" for
that application), will benefit from this fix. The larger the ratio of
the image surface to the portion being copied, the larger the benefit.

Floating-point conversion (3x faster)
-------------------------------------
 xlib-rgba  pattern_create_radial-16    27.75 ->   3.93 :  2.94x speedup
██
image-rgb   pattern_create_radial-16    26.06 ->   3.74 :  2.90x speedup
█▉

Thanks to Daniel Amelang, (and others who had contributed the idea
earlier), for this nice improvement in the speed of converting
floating-point values to fixed-point.

Text rendering (1.3 - 2x faster)
------------------------------
 xlib-rgba text_image_rgba_source-256  319.73 ->  62.40 :  2.13x speedup
█▏
image-rgb    text_solid_rgba_over-64     2.85 ->   0.88 :  1.35x speedup
▍

I don't think we've ever set out to improve text performance
specifically, but we did it a bit anyway. I believe the extra
improvement in the xlib backend is due to Monty's image copying fix
above, and the rest is due to the floating-point conversion speedup.

Thin stroke improvements (1.5x faster)
---------------------------------------------
image-rgb               world_map-800  1641.09 -> 414.77 :  1.65x speedup
▋
 xlib-rgba              world_map-800  1939.66 -> 529.94 :  1.52x speedup
▌

The most modest stuff to announce in this release is the 50%
improvement I made in the world_map case. This is in improvement that
should help basically anything that is doing strokes with many
straight line segments, (and the thinner the better, since that makes
tessellation dominate rasterization). The fixes here are to use a
custom quadrilateral tessellator rather than the generic tessellator
for straight line segments and the miter joins.

Performance results from the Nokia 770
--------------------------------------
 xlib-rgba          subimage_copy-512     55.88 ->     2.04 : 27.34x speedup
██████████████████████████▍
 xlib-rgb     text_image_rgb_over-256   1487.58 ->   294.43 :  5.05x speedup
████
image-rgb   pattern_create_radial-16     187.13 ->    91.86 :  2.04x speedup
█
 xlib-rgba              world_map-800  21261.41 -> 15628.02 :  1.36x speedup
▍

Here we see that the subimage_copy improvement was only about half as
large as the corresponding improvement on my laptop, (27x faster
compared to 54x) and the floating-point conversion fix also was quite
as significant, (2x compared to 3x). Oddly the improvement to text
rendering performance was more than twice as good (5x compared to
2x). I don't know what the reason for that is, but I don't think it's
anything anybody should complain about.

Release 1.2.6 (2006-11-02 Behdad Esfahbod <behdad@behdad.org>)
==============================================================
This is the third bug fix release in the 1.2 series, coming less than
two months after the 1.2.4 release made on August 18.

The 1.2.4 release turned out to be a pretty solid one, except for a crasher
bug when forwarding an X connection where the client and the server have
varying byte orders, eg. from a PPC to an i686.  Other than that, various
other small bugs have been fixed.

Various improvements have been made in the testing infrastructure to prevent
false positives, and to make sure the generated cairo shared object behaves as
expected in terms of exported symbols and relocations.

There were a total of 89 changes since 1.2.4.  The following list the most
important ones:

Common fixes
------------
- Avoid unsigned loop control variable to eliminate infinite,
  memory-scribbling loop. (#7593)
- Fix cairo_image_surface_create to report INVALID_FORMAT errors.
  Previously the detected error was being lost and a nil surface was
  returned that erroneously reported CAIRO_STATUS_NO_MEMORY.
- Change _cairo_color_compute_shorts to not rely on any particular
  floating-point epsilon value. (#7497)
- Fix infinite-join test case (bug #8379)
- Pass correct surface to create_similar in _cairo_clip_init_deep_copy().

PS/PDF fixes
------------
- Fix Type 1 embedding in PDF.
- Correct the value of /LastChar in the PDF Type 1 font dictionary.
- Improve error checking in TrueType subsetting.
- Compute right index when looking up left side bearing. (bug #8180)
- Correct an unsigned to signed conversion problem in truetype subsetting
  bbox.
- Type1 subsetting: Don't put .notdef in Encoding when there are 256 glyphs.
- Add cairo version to PS header / PDF document info dictionary.
- Set CTM before path construction.

Win32 fixes
-----------
- Get correct unhinted outlines on win32. (bug 7603)
- Make cairo as a win32 static library possible.
- Use CAIRO_FORMAT_RGB24 for BITSPIXEL==32 surfaces too.

Build system fixes
------------------
- Define WINVER if it's not defined. (bug 6456)
- Fix the AMD64 final link by removing SLIM from pixman.
- Misc win32 compilation fixes.
- Add Sun Pro C definition of pixman_private.
- Use pixman_private consistently as prefix not suffix.
- Added three tests check-plt.sh, check-def.sh, and check-header.sh that check
  that the shared object, the .def file, and the public headers agree about
  the exported symbols.
- Require pkg-config 0.19. (#8686)


Release 1.2.4 (2006-08-18 Carl Worth <cworth@cworth.org>)
=========================================================
This is the second bug fix release in the 1.2 series, coming less than
two weeks after the 1.2.2 release made on August 8.

The big motivation for a quick release was that there were a log of
build system snags that people ran into with the 1.2.2 release. But,
by the time we got those all done, we found that we had a bunch of
fixes for cairo's rendering as well. So there's a lot of goodness in
here for such a short time period.

Rendering fixes
---------------
Fix image surfaces to not be clipped when used as a source (Vladimir Vukicevic)
http://gitweb.freedesktop.org/?p=cairo;a=commit;h=72e25648c4c4bc82ddd938aa4e05887a293f0d8b

Fix a couple of corner cases in dashing degenerate paths (Jeff Muizelaar)
http://gitweb.freedesktop.org/?p=cairo;a=commit;h=fbb1758ba8384650157b2bbbc93d161b0c2a05f0

Fix support for type1 fonts on win32 (Adrian Johnson)
http://gitweb.freedesktop.org/?p=cairo;a=commit;h=da1019c9138695cb838a54f8b871bbfd0e8996d7

Fix assertion failure when rotating bitmap fonts (Carl Worth)
http://gitweb.freedesktop.org/?p=cairo;a=commit;h=0bfa6d4f33b8ddb5dc55bbe419c15df4af856ff9

Fix assertion failure when calling cairo_text_path with bitmap fonts (Carl Worth)
http://gitweb.freedesktop.org/?p=cairo;a=commit;h=9878a033531e6b96b5f27e69e10e90dee7440cd9

Fix mis-handling of cairo_close_path in some situations (Tim Rowley, Carl Worth)
http://gitweb.freedesktop.org/?p=cairo;a=commit;h=53f74e59faf1af78f2f0741ccf1f23aa5dad4efc

Respect font_matrix translation in _cairo_gstate_glyph_path (Behdad Esfahbod)
http://gitweb.freedesktop.org/?p=cairo;a=commit;h=f183b835b111d23e838889178aa8106ec84663b3

Fix vertical metrics adjustment to work with non-identity shapes (Behdad Esfahbod)
http://gitweb.freedesktop.org/?p=cairo;a=commit;h=b7bc263842a798d657a95e539e1693372448837f

[PS] Set correct ImageMatrix in _cairo_ps_surface_emit_bitmap_glyph_data (Behdad Esfahbod)
http://gitweb.freedesktop.org/?p=cairo;a=commit;h=d47388ad759b0a1a0869655a87d9b5eb6ae2445d

Build system fixes
------------------
Fix xlib detection to prefer pkg-config to avoid false libXt dependency (Behdad Esfahbod)
http://gitweb.freedesktop.org/?p=cairo;a=commit;h=0e78e7144353703cbd28aae6a67cd9ca261f1d68

Fix typos causing win32 build problem with PS,PDF, and SVG backends (Behdad Esfahbod)
http://gitweb.freedesktop.org/?p=cairo;a=commit;h=aea83b908d020e26732753830bb3056e6702a774

Fix configure cache to not use stale results (Behdad Esfahbod)
http://gitweb.freedesktop.org/?p=cairo;a=commit;h=6d0e3260444a2d5b6fb0cb223ac79f1c0e7b3a6e

Fix to not pass unsupported warning options to the compiler (Jens Granseuer)
http://gitweb.freedesktop.org/?p=cairo;a=commit;h=97524a8fdb899de1ae4a3e920fb7bda6d76c5571

Fix to allow env. variables such as png_REQUIRES to override configure detection (Jens Granseuer)
http://gitweb.freedesktop.org/?p=cairo;a=commit;h=abd16e47d6331bd3811c908e524b4dcb6bd23bf0

Fix test suite to not use an old system cairo when converting svg2png (Behdad Esfahbod)
http://gitweb.freedesktop.org/?p=cairo;a=commit;h=6122cc85c8f71b1ba2df3ab86907768edebe1781

Fix test suite to not require signal.h to be present (Behdad Esfahbod)
http://gitweb.freedesktop.org/?p=cairo;a=commit;h=6f8cf53b1e1ccdbe1ab6a275656b19c6e5120e40

Code cleanups
-------------
Many useful warnings cleanups from sparse, valgrind, and careful eyes
(Kjartan Maraas, Pavel Roskin)

Release 1.2.2 (2006-08-08 Carl Worth <cworth@cworth.org>)
=========================================================
This is the first bug fix release in the 1.2 series since the original
1.2.0 release made six weeks ago.

There were some very serious bugs in the 1.2.0 release, (see below),
so everybody is encouraged to upgrade from 1.2.0 to 1.2.2. The 1.2.2
release maintains source and binary compatibility with 1.2.0 and does
not make any API additions.

Fix crashes with BGR X servers
------------------------------
With cairo 1.2.0 many people reported problems with all cairo-using
programs, (including all GTK+ programs with GTK+ >= 2.8) immediately
crashing with a complaint about an unsupported image format. This bug
affected X servers that do not provide the Render extension and that
provide a visual with BGR rather than RGB channel order.

report:	https://bugs.freedesktop.org/show_bug.cgi?id=7294
fix:	http://gitweb.freedesktop.org/?p=cairo;a=commit;h=9ae66174e774b57f16ad791452ed44efc2770a59

Fix the "disappearing text" bug
-------------------------------
With cairo 1.2.0 many people reported that text would disappear from
applications, sometimes reappearing with mouse motion or
selection. The text would disappear after the first space in a string
of text. This bug was caused by an underlying bug in (very common) X
servers, and only affected text rendered without antialiasing, (either
a bitmap font or a vector font with antialiasing disabled). The bug
was also exacerbated by a KDE migration bug that caused antialiasing
to be disabled more than desired.

report:	https://bugs.freedesktop.org/show_bug.cgi?id=7494
fix:	http://gitweb.freedesktop.org/?p=cairo;a=commit;h=456cdb3058f3b416109a9600167cd8842300ae14
see also:
Xorg:	https://bugs.freedesktop.org/show_bug.cgi?id=7681
KDE:	http://qa.mandriva.com/show_bug.cgi?id=23990

Fix broken image fallback scaling (aka. "broken printing")
----------------------------------------------------------
The various "print" backends, (pdf, ps, and svg), sometimes fallback
to using image-based rendering for some operations. In cairo 1.2.0
these image fallbacks were scaled improperly. Applications using cairo
can influence the resolution of the image fallbacks with
cairo_surface_set_fallback_resolution. With the bug, any value other
than 72.0 would lead to incorrect results, (larger values would lead
to increasingly shrunken output).

report:	https://bugs.freedesktop.org/show_bug.cgi?id=7533
fix:	http://gitweb.freedesktop.org/?p=cairo;a=commit;h=1feb4291cf7813494355459bb547eec604c54ffb

Fix inadvertent semantic change of font matrix translation (Behdad Esfahbod)
----------------------------------------------------------------------------
The 1.2.0 release introduced an inadvertent change to how the
translation components of a font matrix are interpreted. In the 1.0
series, font matrix translation could be used to offset the glyph
origin, (though glyph metrics were reported incorrectly in
1.0). However in 1.2.0, the translation was applied to the advance
values between each glyph. The 1.2.0 behavior is fairly useless in
practice, and it was not intentional to introduce a semantic
change. With 1.2.2 we return to the 1.0 semantics, with a much better
implementation that provides correct glyph metrics.

fix:	http://gitweb.freedesktop.org/?p=cairo;a=commit;h=84840e6bba6e72aa88fad7a0ee929e8955ba9051

Fix create_similar to preserve fallback resolution and font options (Behdad Esfahbod)
-------------------------------------------------------------------------------------
There has been a long-standing issue with cairo_surface_create_similar
such that font options and other settings from the original
destination surface would not be preserved to the intermediate
"similar" surface. This could result in incorrect rendering
(particularly with respect to text hinting/antialiasing) with
fallbacks, for example.

report:	https://bugs.freedesktop.org/show_bug.cgi?id=4106
fixes:	http://gitweb.freedesktop.org/?p=cairo;a=commit;h=9fcb3c32c1f16fe6ab913e27eb54d18b7d9a06b0
	http://gitweb.freedesktop.org/?p=cairo;a=commit;h=bdb4e1edadb78a2118ff70b28163f8bd4317f1ec

xlib: Fix text performance regression from 1.0 to 1.2.0 (Vladimir Vukicevic)
----------------------------------------------------------------------------
Several people noticed that upgrading from cairo 1.0 to cairo 1.2.0
caused a significant performance regression when using the xlib
backend. This performance regression was particularly noticeable when
doing lots of text rendering and when using a high-latency connection
to the X server, (such as a remote X server over an ssh
connection). The slowdown was identified and fixed in 1.2.2.

report:	https://bugs.freedesktop.org/show_bug.cgi?id=7514
fix:	http://gitweb.freedesktop.org/?p=cairo;a=commit;h=b7191885c88068dad57d68ced69a752d1162b12c

PDF: Eliminate dependency on FreeType library dependency (Adrian Johnson)
-------------------------------------------------------------------------
The cairo 1.2 series adds a supported pdf backend to cairo. In cairo
1.2.0 this backend required the freetype library, which was an
undesirable dependency on systems such as win32, (cairo is designed to
always prefer the "native" font system). As of cairo 1.2.2 the
freetype library is not required to use the pdf backend on the win32
platform.

report:	https://bugs.freedesktop.org/show_bug.cgi?id=7538
fix:	http://gitweb.freedesktop.org/?p=cairo;a=commit;h=a0989f427be87c60415963dd6822b3c5c3781691

PDF: Fix broken output on amd64 (Adrian Johnson)
------------------------------------------------
report:	http://bugzilla.gnome.org/show_bug.cgi?id=349826
fix:	http://gitweb.freedesktop.org/?p=cairo;a=commit;h=f4b12e497b7ac282b2f6831b8fb68deebc412e60

PS: Fix broken output for truetype fonts > 64k (Adrian Johnson)
---------------------------------------------------------------
fix:	http://gitweb.freedesktop.org/?p=cairo;a=commit;h=067d97eb1793a6b0d0dddfbd0b54117844511a94

PDF: Fix so that dashing doesn't get stuck on (Kent Worsnop)
------------------------------------------------------------
Kent notices that with the PDF backend in cairo 1.2.0 as soon as a
stroke was performed with dashing, all subsequent strokes would also
be dashed. There was no way to turn dashing off again.

fix:	http://gitweb.freedesktop.org/?p=cairo;a=commit;h=778c4730a86296bf0a71080cf7008d7291792256

Fix memory leaks in failure paths in gradient creation (Alfred Peng)
--------------------------------------------------------------------
fix:	http://gitweb.freedesktop.org/?p=cairo;a=commit;h=db06681b487873788b51a6766894fc619eb8d8f2

Fix memory leak in _cairo_surface_show_glyphs (Chris Wilson)
------------------------------------------------------------
report:	https://bugs.freedesktop.org/show_bug.cgi?id=7766
fix:	http://gitweb.freedesktop.org/?p=cairo;a=commit;h=e2fddcccb43d06486d3680a19cfdd5a54963fcbd

Solaris: Add definition of cairo_private for some Sun compilers (Alfred Peng)
-----------------------------------------------------------------------------
report:	https://bugzilla.mozilla.org/show_bug.cgi?id=341874
fix:	http://gitweb.freedesktop.org/?p=cairo;a=commit;h=04757a3aa8deeff3265719ebe01b021638990ec6

Solaris: Change version number of Sun's Xorg server with buggy repeat (Brian Cameron)
-------------------------------------------------------------------------------------
report: https://bugs.freedesktop.org/show_bug.cgi?id=7483
fix:	http://gitweb.freedesktop.org/?p=cairo;a=commit;h=e0ad1aa995bcec4246c0b8ab0d5a5a79871ce235

Various memory leak fixes
-------------------------
Fix memory leak in _cairo_surface_show_glyphs (bug 7766)
Fix file handle leak in failure path (bug 7616)
Fix some memory leaks in the test cases.
Fix some memory leaks in font subsetting code used in print backends.

Documentation improvements (Behdad Esfahbod)
--------------------------------------------
Added new documentation for several functions (cairo_show_page,
cairo_copy_page, cairo_in_stroke, cairo_in_fill).

Fixed some syntax errors that were preventing some existing
documentation from being published.

Fixed several minor typographical errors.

Added an index for new symbols in 1.2.

Release 1.2.0 (2006-06-27 Carl Worth <cworth@cworth.org>)
=========================================================
This is the culmination of the work that has gone on within the 1.1
branch of cairo.

There has been one API addition since the cairo 1.1.10 snapshot:

	cairo_xlib_surface_get_width
	cairo_xlib_surface_get_height

There's also a new feature without any API change:

	Dots can now be drawn by using CAIRO_LINE_CAP_ROUND with
	degenerate sub-paths, (cairo_move_to() followed by either
	cairo_close_path() or a cairo_line_to() to the same location).

And at least the following bugs have been fixed:

 6759  fontconfig option AntiAlias doesn't work in cairo 1.1.2
 6955  Some characters aren't displayed when using xlib (cache u...
 7268  positive device_offset values don't work as source
 * PDF emit_glyph function needs to support bitmapped glyphs
 * PS emit_glyph function needs to support bitmapped glyphs
 * SVG emit_glyph function needs to support bitmapped glyphs
 * PDF: minefield page one is falling back unnecessarily
 * PS/PDF: Fix broken placement for vertical glyphs
 * PS: Fix to not draw BUTT-capped zero-length dash segments
 * Do device offset before float->fixed conversion
   http://bugzilla.gnome.org/show_bug.cgi?id=332266
 * PS: Fix source surfaces with transformations
 * PS: Fix to not draw BUTT-capped degnerate sub-paths
 * PS: Don't walk off end of array when printing "~>"
 * Fix some memory leaks in the test suite rig
 * SVG: Fix memory leak when using cairo_mask
 * Fix EXTEND_REFLECT and EXTEND_PAD to not crash (though these are
   still not yet fully implemented for surface patterns).

This has been a tremendous effort by everyone, and I'm proud to have
been a part of it. Congratulations to all contributors to cairo!

Snapshot 1.1.10 (2006-06-16 Carl Worth <cworth@cworth.org>)
===========================================================
This is the fifth in a series of snapshots working toward the 1.2
release of cairo.

The primary motivation for this snapshot is to fix a long-standing bug
that had long been silent, but as of the 1.1.8 snapshot started
causing crashes when run against 16-bit depth X servers, (often Xvnc
or Xnest). The fix for this adds a new CAIRO_FORMAT_RGB16_565 to the
API.

This snapshot also includes a rewrite of cairo's SVG backend to
eliminate the dependency on libxml2. With this in place, cairo 1.2
will not depend on any libraries that cairo 1.0 did not.

As usual, there are also a few fixes for minor bugs.

Snapshot 1.1.8 (2006-06-14 Carl Worth <cworth@cworth.org>)
==========================================================
This is the fourth in a series of snapshots working toward the 1.2
release of cairo. At this point, all major features of the 1.2 release
are in place, leaving just a few bug fixes left.

In particular, there well be no additional API changes between this
1.1.8 snapshot and the 1.2 release.

The announcement for 1.1.6 mentioned several API changes being
considered. Only one of these changes was actually implemented
(set_dpi -> fallback_resolution). This change does introduce one
source-level incompatibility with respect to previous 1.1.x snapshots,
so see below for details.

Here is an abbreviated summary of changes since the 1.1.6 snapshot:

** API Change **
----------------
According to the plan mentioned in the 1.1.6 notes, one source-level
incompatible change has been implemented. The following three
functions have been removed from cairo's API:

	cairo_pdf_surface_set_dpi
	cairo_ps_surface_set_dpi
	cairo_svg_surface_set_dpi

and in their place the following function has been added:

	cairo_surface_set_fallback_resolution

The signature and semantics of the function remains the same, so it is
a simple matter of changing the name of the function when calling
it. As a transition mechanism, this snapshot will (on many systems)
build to include the old symbols so that code previously compiled will
still run. However, all source code using the old names must be
updated before it will compile. And the upcoming 1.2 release is not
anticipated to include the old symbols.

Finally, it should be pointed out that the old symbols never existed
in the supported API of any stable release of cairo. (In the stable
1.0 releases the PDF, PS, and SVG backends were advertised as
experimental and unstable.)

And, as always, cairo continues to maintain source and binary
compatibility between major releases. So applications compiled against
supported backends in a stable release of cairo (1.0.4 say) will
continue to compile and run without modification against new major
releases (1.2.0 say) without modification.

API additions
-------------
The following new functions have been added to cairo's API:

	cairo_surface_get_content
	cairo_debug_reset_static_data
	cairo_image_surface_get_data
	cairo_image_surface_get_format
	cairo_image_surface_get_stride
	cairo_win32_font_face_create_for_hfont

New, backend-specific pkg-config files
--------------------------------------
In addition to the original cairo.pc file, cairo will also now install
a pkg-config files for each configured backend, (for example
cairo-pdf.pc, cairo-svg.pc, cairo-xlib.pc, cairo-win32.pc, etc.) this
also includes optional font backends (such as cairo-ft.pc) and the
optional png functionality (cairo-png.pc).

These new pkg-config files should be very convenient for allowing
cairo-using code to easily check for the existing of optional
functionality in cairo without having to write complex rules to grub
through cairo header files or the compiled library looking for
symbols.

Printing backend (PS, PDF, and SVG)
-----------------------------------
Improving the quality of the "printing" backends has been a priority
of the development between cairo 1.1.6 and cairo 1.1.8.

The big improvement here is in the area of text output. Previously, at
best, text was output as paths without taking advantage of any font
support available in the output file format.

Now, at the minimum text paths will be shared by using type3 fonts
(for PS and PDF---and similarly, defs for SVG). Also, if possible,
type3 and truetype fonts will be embedded in PostScript and PDF
output. There are still some known bugs with this, (for example,
selecting text in a cairo-generated PDF file with an embedded truetype
font does not work). So there will be some more changes in this area
before cairo 1.2, but do try test this feature out as it exists so
far.

Many thanks to Kristian Høgsberg for the truetype and type1 font
embedding.

win32 backend
-------------
Performance improvements by preferring GDI over pixman rendering when possible.
Fixes for text rendering.

xlib backend
------------
Fix potentially big performance bug by making xlib's create_similar
try harder to create a pixmap of a depth matching that of the screen.

Bug fixes
---------
Among various other fixes, the following bugs listed in bugzilla have
been fixed:

    Bug 2488: Patch to fix pixman samping location bug (#2488).
    https://bugs.freedesktop.org/show_bug.cgi?id=2488

    Bug 4196: undef MIN an MAX before defining to avoid duplicate definition
    https://bugs.freedesktop.org/show_bug.cgi?id=4196

    Bug 4723: configure.in: Fix m4 quoting when examining pkg-config version
    https://bugs.freedesktop.org/show_bug.cgi?id=4723

    Bug 4882: Flag Sun's X server has having buggy_repeat.
    https://bugs.freedesktop.org/show_bug.cgi?id=4882

    Bug 5306: test/pdf2png: Add missing include of stdio.h
    https://bugs.freedesktop.org/show_bug.cgi?id=5306

    Bug 7075: Fix make clean to remove cairo.def
    https://bugs.freedesktop.org/show_bug.cgi?id=7075

(Many thanks to Behdad Esfahbod for helping us track down and fix many
of these.)

Snapshot 1.1.6 (2006-05-04 Carl Worth <cworth@cworth.org>)
==========================================================
This is the third in a series of snapshots working toward the imminent
1.2 release of cairo. For a list of items still needing work on the
cairo 1.2 roadmap, please see:

	http://cairographics.org/ROADMAP

As can be seen in that list, there are no longer any API additions
left on the roadmap. Instead, there is a feature (PDF type 3 fonts) a
performance optimization (X server gradients) and a list of bug
fixes. This gives us a fair amount of freedom to cut the 1.2 release
at almost any point by deciding to defer remaining bug fixes to
subsequent maintenance releases such as 1.2.2 and 1.2.4.

Before we will do that, we must first be wiling to commit to all the
new API additions. As a heads-up, there are a couple of potential API
changes being considered. (Note that these are changes to new API
introduced during 1.1 so these will not introduce API
incompatibilities compared to the stable 1.0 series). The changes
being considered are:

  cairo_get_group_target: may acquire x and y offset return
	parameters. May also be eliminated in favor of
	cairo_get_target assuming its role

  cairo_pdf_surface_set_dpi:
  cairo_ps_surface_set_dpi:
  cairo_svg_surface_set_dpi: These functions may be removed in favor
	of a new cairo_surface_set_fallback_resolution

Additionally there is the possibility of a slight change in the
semantics of cairo_set_line_width. We believe the current behavior of the sequence:

	cairo_set_line_width; ... change CTM ...; cairo_stroke;

is buggy. It is currently behaving the same as:

	... change CTM ...; cairo_set_line_width; cairo_stroke;

We are considering fixing this bug before 1.2 with the hope that
nobody is already relying on the buggy behavior described here. Do
shout if you suspect you might be in that position.

The items included in this snapshot (since the 1.1.4 snapshot) are
described below.

API additions
-------------
The long-awaited group-rendering support is now available with the
following function calls:

	cairo_push_group
	cairo_push_group_with_content
	cairo_pop_group
	cairo_pop_group_to_source
	cairo_get_group_target

This API provides a much more convenient mechanism for doing rendering
to an intermediate surface without the need to manually create a
temporary cairo_surface_t and a temporary cairo_t and clean them up
afterwards.

Add the following missing get function to complement
cairo_surface_set_device_offset:

	cairo_surface_get_device_offset

PDF backend (API addition)
--------------------------
The PDF backend now provides for per-page size changes, (similar to
what the PostScript backend got in the 1.1.4 snapshot). The new API
is:

	cairo_pdf_surface_set_size

Xlib backend (API additions)
----------------------------
The following functions have been added to allow the extraction of
Xlib surface:

	cairo_xlib_surface_get_display
	cairo_xlib_surface_get_drawable
	cairo_xlib_surface_get_screen
	cairo_xlib_surface_get_visual
	cairo_xlib_surface_get_depth

XCB backend (experimental)
--------------------------
Update backend so that it now compiles with the recent XCB 0.9 release.

Bug fixes and memory leak cleanup
---------------------------------
Various little things, nothing too significant though.

Snapshot 1.1.4 (2006-05-03 Carl Worth <cworth@cworth.org>)
==========================================================
This is the second in a series of snapshots working toward the
upcoming 1.2 release of cairo. For a list of items still needing work
on the cairo 1.2 roadmap, please see:

	http://cairographics.org/ROADMAP

The items included in this snapshot (since the 1.1.2 snapshot) are
described below.

PostScript backend: new printing-oriented API
---------------------------------------------
We anticipate that with cairo 1.2, toolkits will begin to use cairo
for printing on systems that use PostScript as the spool format. To
support this use case, we have added 4 new function calls that are
specific to the PostScript backend:

	cairo_ps_surface_set_size
        cairo_ps_surface_dsc_comment
        cairo_ps_surface_dsc_begin_setup
        cairo_ps_surface_dsc_begin_page_setup

These functions allow variation of the page size/orientation from one
page to the next in the PostScript output. They also allow the toolkit
to provide per-document and per-page printer control options in a
device-independent way, (for example, by using PPD options and
emitting them as DSC comments into the PostScript output). This should
allow toolkits to provide very fine-grained control of many options
available in printers, (media size, media type, tray selection, etc.).

SVG backend: builds by default, version control
-----------------------------------------------
The SVG backend continues to see major improvements. It is expected
that the SVG backend will be a supported backend in the 1.2
release. This backend will now be built by default if its dependencies
(freetype and libxml2) are met.

Additionally, the SVG backend now has flexibility with regard to what
version of SVG it targets. It will target SVG 1.1 by default, which
will require image fallbacks for some of the "fancier" cairo
compositing operators. Or with the following new function calls:

	cairo_svg_surface_restrict_to_version
	cairo_svg_get_versions
	cairo_svg_version_to_string

it can be made to target SVG 1.2 in which there is native support for
these compositing operators.

Bug fixes
---------
At least the following bugs have been fixed since the 1.1.2 snapshot:

crash at XRenderAddGlyphs
https://bugs.freedesktop.org/show_bug.cgi?id=4705

Can't build cairo-1.1.2 on opensolaris due to " void function cannot return value"
https://bugs.freedesktop.org/show_bug.cgi?id=6792

Missing out-of-memory check at gfx/cairo/cairo/src/cairo-atsui-font.c:185
https://bugzilla.mozilla.org/show_bug.cgi?id=336129

A couple of memory leaks.

Snapshot 1.1.2 (2006-04-25 Carl Worth <cworth@cworth.org>)
==========================================================
This is the first in a series of snapshots working toward the upcoming
1.2 release of cairo. (Subsequent snapshot will use successive even
numbers for the third digit, 1.1.4, 1.1.6, etc.) This snapshot is
backwards-compatible with the 1.0 series---it makes a few API
additions but does not remove any API.

PostScript and PDF backends are no longer "experimental"
--------------------------------------------------------
The major theme of the 1.2 release is improved PostScript and PDF
backends for cairo. Unlike the 1.0 series, in the 1.2 series these
backends will not be marked as experimental and will be enabled by
default. We encourage people to test this snapshot and the PS/PDF
backends in particular as much as possible.

The PostScript and PDF output is not yet ideal.

 * One major problem with the PostScript output is that image
   fallbacks are used more often than strictly necessary, and the
   image fallbacks are at a lower resolution than desired, (the
   cairo_ps_surface_set_dpi call is ignored).

  * The major drawback of the current PDF backend implementation is
    its text support. Every glyph is represented by a filled path in
    the PDF file. The causes file sizes to be much larger and
    rendering to be much slower than desired.

It is anticipated that both of these shortcomings will see some
improvements before the final 1.2 release.

In spite of those shortcomings, we hope that the PS and PDF backends
will yield faithful results for pretty much any cairo operations you
can throw at them. Please let us know if you are getting obviously
"different" results from the PS/PDF backends than from the image or
xlib backends.

Other new experimental backends
-------------------------------
This snapshot includes three new backends that did not exist in the
1.0 series:

	* beos backend

	* directfb backend

	* svg backend

These are all currently marked "experimental" and are disabled by
default. But the SVG backend in particular has seen a lot of recent
development and is very close to passing the entire cairo test
suite. It is possible that this backend will become a fully supported
backend by the time of the cairo 1.2 release.

Public API additions
--------------------
There have been a few new API functions added to cairo, including:

New get_type functions for querying sub-types of object:

	cairo_surface_get_type
	cairo_pattern_get_type
	cairo_font_face_get_type
	cairo_scaled_font_get_type

More convenience in working with cairo_scaled_font_t with new getter
functions:

	cairo_scaled_font_get_font_face
	cairo_scaled_font_get_font_matrix
	cairo_scaled_font_get_ctm
	cairo_scaled_font_get_font_options

As well as a convenience function for setting a scaled font into a
cairo context:

	cairo_set_scaled_font

and a function to allow text extents to be queried directly from a
scaled font, (without requiring a cairo_surface_t or a cairo_t):

	cairo_scaled_font_text_extents

These new scaled font functions were motivated by the needs of the
pango library.

Finally, a new path-construction function was added which clears the
current point in preparation for a new sub path. This makes cairo_arc
easier to use in some situations:

	cairo_new_sub_path

Before the 1.2 release is final we do still plan a few more API
additions specifically motivated by the needs of Mozilla/Firefox.

Optimizations and bug fixes
---------------------------
Shortly after the 1.0 maintenance series branched off the mainline
there was a major rework of the cairo font internals. This should
provide some good performance benefits, but it's also another area
people should look at closely for potential regressions.

There has not yet been any widespread, systematic optimization of
cairo, but various performance improvements have been made, (and some
of them are fairly significant). So if some things seem faster than
1.0 then things are good. If there are any performance regressions
compared to 1.0 then there is a real problem and we would like to hear
about that.

There has been a huge number of bug fixes---too many to mention in
detail. Again, things should be better, and never worse compared to
1.0. Please let us know if your testing shows otherwise.

Release 1.0.2 (2005-10-03 Carl Worth <cworth@cworth.org>)
=========================================================
For each bug number XXXX below, see:

	https://bugs.freedesktop.org/show_bug.cgi?id=XXXX

for more details.

General bug fixes
-----------------
 * 4408 - Add support for dashing of stroked curves
	  (Carl Worth)

 * 4409 - Fix dashing so that each dash is capped on both ends
	  (Carl Worth)

 * 4414 - Prevent SIGILL failures (proper use of -mmmx and -msse flags)
	  (Sebastien Bacher, Billy Biggs)

 * 4299 - Fix crashes with text display in multi-threaded program
	  (Alexey Shabalin, Carl Worth)

 * 4401 - Do not use sincos function since it is buggy on some platforms)
	  (Tim Mooney, Carl Worth)

 * 4245 - Fix several bugs in the test suite exposed by amd64 systems
	  (Seemant Kulleen, Carl Worth)

 * 4321 - Add missing byteswapping on GetImage/PutImage
	  (Sjoerd Simons, Owen Taylor)

 * 4220 - Make the check for rectangular trapezoids simpler and more accurate
	  (Richard Stellingwerff, Owen Taylor)

 * 4260 - Add missing channel-order swapping for antialised fonts
	  (Barbie LeVile, Owen Taylor)

 * 4283 - Fix compilation failure with aggressive inlining (gcc -O3)
	  (Marco Manfredini, Owen Taylor)

 * 4208 - Fix some warnings from sparse
	  (Kjartan Maraas, Billy Biggs)

 * 4269 - Fix to not crash when compiled with -fomit-frame-pointer
	  (Ronald Wahl, Owen Taylor)

 * 4263 - Improve performance for vertical gradients
	  (Richard Stellingwerff, Owen Taylor)

 * 4231
 * 4298 - Accomodate gentoo and Mandriva versions in X server vendor string check
	  (Billy Biggs, Frederic Crozat, Owen Taylor)

win32-specific fixes
--------------------
 * 4599 - Fix "missing wedges" on some stroked paths (win32)
	  (Tim Rowley, Jonathan Watt, Bertram Felgenhauer, Carl Worth, Keith Packard)

 * 4612 - Fix disappearing text if first character out of surface (win32)
	  (Tim Rowley)

 * 4602 - Fix shutdown of cairo from failing intermediate, size-0 bitmaps (win32)
	  Aka. the "white rectangles" bug from mozilla-svg testing
	  (Tim Rowley)

 * Various portability improvements for win32
	  (Hans Breuer, Owen Taylor, Carl Worth)

 * 4593 - Fix font sizes to match user expectations (win32)
	  (Tor Lillqvist, Owen Taylor)

 * 3927 - Fix to report metrics of size 0 for glyph-not-available (win32)
	  (Hans Breuer, Owen Taylor, Tor Lillqvist)

 * Add locking primitives for win32
	  (Hans Breuer)

xlib-specific fixes
-------------------
 * Fix crash from size-0 pixmap due to empty clip region (xlib)
	  (Radek Doulík, Carl Worth)

Release 1.0.0 (2005-08-24 Carl Worth <cworth@cworth.org>)
=========================================================
Experimental backends
---------------------
 * The Glitz, PS, PDF, Quartz, and XCB backends have been declared
   experimental, and are not part of the API guarantees that accompany
   this release. They are not built by default, even when the required
   libraries are available, and must be enabled explicitly with
   --enable-ps, --enable-pdf, --enable-quartz or --enable-xcb.

   It is very painful for us to be pushing out a major release without
   these backends enabled. There has been a tremendous amount of work
   put into each one and all are quite functional to some
   extent. However, each also has some limitations. And none of these
   backends have been tested to the level of completeness and
   correctness that we expect from cairo backends.

   We do encourage people to experiment with these backends and report
   success, failure, or means of improving them.

Operator behavior
-----------------
 * Prior to 0.9.0 the SOURCE, CLEAR and a number of other operators
   behaved in an inconsistent and buggy fashion and could affect areas
   outside the clip mask. In 0.9.0, these six "unbounded" operators
   were fixed to consistently clear areas outside the shape but within
   the clip mask.  This is useful behavior for an operator such as IN,
   but not what was expected for SOURCE and CLEAR. So, in this release
   the behavior of SOURCE and CLEAR has been changed again. They now
   affect areas only within both the source and shape. We can write
   the new operators as:

     SOURCE: dest' = (mask IN clip) ? source : dest
     CLEAR:  dest' = (mask IN clip) ? 0 : dest

Behavior and API changes
------------------------
 * Setting the filter on a gradient pattern would change the
   interpolation between color stops away from the normal linear
   interpolation. This dubious behavior has been removed.

 * The CAIRO_CONTENT_VALID() and CAIRO_FORMAT_VALID() macros --
   implementation details that leaked into cairo.h -- have been moved
   into an internal header.

 * The cairo_show_text function now advances the current point
   according to the total advance values of the string.

API additions
-------------
 * cairo_set_dash can now detect error and can set
   CAIRO_STATUS_INVALID_DASH.

Features
--------
 * When compiled against recent versions of fontconfig and FreeType,
   artificial bold fonts can now be turned on from fonts.conf using
   the FC_EMBOLDEN fontconfig key.

Optimization
------------
 * The compositing code from the 'xserver' code tree has now been
   completely merged into libpixman. This includes MMX optimization of
   common operations.

 * The image transformation code in libpixman has been improved and
   now performs significantly faster.

Bug fixes
---------
 * Several crashes related to corruption in the font caches have been
   fixed.

 * All test cases now match pixel-for-pixel on x86 and PPC; this
   required fixing bugs in the compositing, stroking, and pattern
   rendering code.

 * Negative dash offsets have been fixed to work correctly.

 * The stroking of paths with mutiple subpaths has now been fixed to
   apply caps to all subpaths rather than just the last one.

 * Many build fixes for better portability on various systems.

 * Lots of other bug fixes, but we're too tired to describe them in
   more detail here.

Release 0.9.2 (2005-08-13 Carl Worth <cworth@cworth.org>)
=========================================================
Release numbering
-----------------
 * You will notice that this release jumped from 0.9.0 to 0.9.2. We've
   decided to use an odd micro version number (eg. 0.9.1) to indicate
   in-progress development between releases. As soon as 0.9.2 is
   tagged, the version will be incremented in CVS to 0.9.3 where it
   will stay until just before 0.9.4 is built, uploaded, and tagged.

   So, even-micro == a released version, odd-micro == something in-between.

Libpixman dependency dropped
----------------------------
 * As of this release, the dependency on an external libpixman has
   been dropped. Instead, the code from libpixman needed for cairo has
   been incorporated into the cairo source tree. The motivation for
   this change is that while cairo's API is stable and ready to be
   maintained after the 1.0 release, libpixman's API is not, so we do
   not want to expose it at this time.

   Also, the incorporation of libpixman into cairo also renames all
   previously-public libpixman symbols in order to avoid any conflict
   with a future release of libpixman

API additions
-------------
 * Macros and functions have been added so that the version of cairo
   can be queried at either compile-time or at run-time. The version
   is made available as both a human-readable string and as a single
   integer:

	CAIRO_VERSION_STRING		   eg. "0.9.2"
	CAIRO_VERSION			   eg. 000902

	const char*
	cairo_version_string (void);	/* eg. "0.9.2" */

	int
	cairo_version (void);		/* eg. 000902 */

   A macro is provided to convert a three-part component version into
   the encoded single-integer form:

	CAIRO_VERSION_ENCODE(X,Y,Z)

   For example, the CAIRO_VERSION value of 000902 is obtained as
   CAIRO_VERSION_ENCODE(0,9,2). The intent is to make version
   comparisons easy, either at compile-time:

	#if CAIRO_VERSION >= CAIRO_VERSION_ENCODE(0,9,2)
	...
	#endif

   Or at run-time:

	if (cairo_version() >= CAIRO_VERSION_ENCODE(0,9,2)) { /* ... */ }

Thread safety
-------------
 * This release adds pthread-based locking (when available) to make
   the caches used by cairo safe for threaded programs. Some may
   remember a failed experiment with this locking between the 0.5.1
   and 0.5.2 snapshots, (where even single-threaded programs that
   linked with -lpthread would deadlock). We believe that that problem
   has been fixed, so we are looking forward to testing and reports
   from users with threaded applications.

Bug fixes
---------
 * The XCB and Quartz backends failed to compiled in the 0.9.0 release
   due to minor syntax errors. These have now been fixed.

 * Various crashes in glitz and pixman due to size 0 glyphs have been
   fixed.

Release 0.9.0 (2005-08-08 Carl Worth <cworth@cworth.org>)
=========================================================
Soname change
-------------
 * In all prior snapshots, the libtool library versioning was set to
   1:0:0. As this release is intended to mark the beginning of
   backwards-compatible releases, the versioning has been incremented
   to 2:0:0. You will notice that the numeric extension on the
   installed library filename will change similarly.

   This change will also require all cairo-using applications to be
   recompiled. We recognize that this may cause some frustration since
   this release is backwards-compatible with 0.6.0 and in that sense
   "shouldn't" require re-compilation. However, since all historical
   snapshots have used the same 1:0:0 version in spite of incompatible
   API changes between them, it was essential that the upcoming 1.0
   release series have distinct library versioning.

   All future releases will use the library versioning to properly
   indicate compatibility between releases. So, any application
   re-compiled now to work with the 0.9.0 will not need to be
   recompiled when a compatible 1.0 release of cairo is made in the
   future.

API additions
-------------
 * Add new function calls to set/get the current antialiasing mode in
   the graphics state:

	cairo_set_antialias
	cairo_get_antialias

   This call accepts the same modes recently added for font options
   (NONE or GRAY) but affects the rendering of geometry other than
   text. The intent of this call is to enable more precise control of
   which pixels are affected by each operation, for example to allow
   for full-scene antialiasing for seam-free rendering. It is not
   expected that non-antialiased rendering will perform better than
   anti-aliased rendering.

 * Three new functions were added to provide support for mixed cairo-
   and non-cairo drawing to the same surface:

	cairo_surface_mark_dirty
	cairo_surface_mark_dirty_rectangle
	cairo_surface_flush

 * The return type of the several "reference" functions was change,
   (API compatibly), from void to the same type as the argument. The
   affected functions are:

	cairo_font_face_reference
	cairo_scaled_font_reference
	cairo_pattern_reference
	cairo_surface_reference
	cairo_reference

   This allows a convenient way to assign and reference in a single
   statement.

Semantic changes
----------------
 * The behavior of cairo_set_source with a pattern with a non-identity
   matrix was previously not well-defined. The new behavior is as
   follows:

	The pattern's transformation matrix will be locked to the
	user space in effect at the time of cairo_set_source(). This means
	that further modifications of the CTM will not affect the source
	pattern.

cairo-win32
-----------
 * Some portability improvements, (eg. workaround for missing stdint.h).

cairo-ft
--------
 * Updated to allow compilation with older versions of freetype.

Bug fixes
---------
 * Fix the unbounded operators to actually produce a correct result,
   (previously the results were artificially restricted to the
   bounding box of whatever shape was being drawn rather than
   extending out infinitely). The fixed operators are:

	CAIRO_OPERATOR_CLEAR
	CAIRO_OPERATOR_SOURCE
	CAIRO_OPERATOR_OUT
	CAIRO_OPERATOR_IN
	CAIRO_OPERATOR_DEST_IN
	CAIRO_OPERATOR_DEST_ATOP

 * Fix cairo_mask and cairo_mask_surface to transform the mask by the
   current transformation matrix (CTM).

 * Fix cairo_set_source to lock the CTM used to transform the pattern.

 * Workaround for X server Render bug involving repeating patterns
   with a general transformation matrix.

 * cairo_get_font_face fixed to return a "nil" font face object rather
   than NULL on error.

 * cairo_set_font_face fixed to not crash if given a NULL font face,
   (which is the documented interface for restoring the default font
   face).

 * Fix xlib glyphset caching to not try to free a NULL glyph.

Snapshot 0.6.0 (2005-07-28 Carl Worth <cworth@cworth.org>)
==========================================================
API changes
-----------
* The prototypes of the following functions have changed:

	cairo_xlib_surface_create_with_xrender_format
	cairo_xlib_surface_create_for_bitmap

  A Screen* parameter has been added to each. This allows the cairo
  xlib backend to work correctly with multi-head X servers.

* The following function has been modified:

	cairo_scaled_font_create

  to accept a cairo_font_options_t*. See below fore more details.

* All opaque, reference-counted cairo objects have now been moved to a
  standard error-handling scheme. The new objects to receive this
  treatment are cairo_font_face_t, cairo_scaled_font_t, and
  cairo_surface_t. (Previous snapshots already provided this scheme
  for cairo_t, cairo_path_t, and cairo_pattern_t.)

  This changes two functions to have a return type of void rather than
  cairo_status_t:

	cairo_scaled_font_extent
	cairo_surface_finish

  And significantly, none of the create functions for any of the
  objects listed above will return NULL. The pointer returned from any
  function will now always be a valid pointer and should always be
  passed to the corresponding destroy function when finished

  The simplest strategy for porting code is to switch from:

	object = cairo_<object>_create ();
	if (object == NULL)
	    goto BAILOUT;

	/* act on object */

	cairo_<object>_destroy (object);

  to:

	object = cairo_<object>_create ();
	if (cairo_<object>_status (object))
	    goto BAILOUT;

	/* act on object */

	cairo_<object>_destroy (object);

   But significantly, it is not required to check for an error status
   before the "act on object" portions of the code above. All
   operations on an object with an error status are, by definition,
   no-ops without side effect. So new code might be written in an
   easier-to-read style of:

	object = cairo_<object>_create ();

	/* act on object */

	cairo_<object>_destroy (object);

   with cairo_<object>_status checks placed only at strategic
   locations. For example, passing an error object to another object,
   (eg. cairo_set_source with an in-error pattern), will propagate the
   error to the subsequent object (eg. the cairo_t). This means that
   error checking can often be deferred even beyond the destruction of
   a temporary object.

API additions
-------------
* New functions for checking the status of objects that have been
  switched to the common error-handling scheme:

	cairo_font_face_status
	cairo_scaled_font_status
	cairo_surface_status

* The _cairo_error function which was added in 0.5.1 has now been made
  much more useful. In 0.5.1 only errors on cairo_t objects passed
  through _cairo_error. Now, an error on any object should pass
  through _cairo_error making it much more reliable as a debugging
  mechanism for finding when an error first occurs.

* Added new font options support with a myriad of functions:

	cairo_font_options_create
	cairo_font_options_copy
	cairo_font_options_destroy

	cairo_font_options_status

	cairo_font_options_merge
	cairo_font_options_equal
	cairo_font_options_hash

	cairo_font_options_set_antialias
	cairo_font_options_get_antialias
	cairo_font_options_set_subpixel_order
	cairo_font_options_get_subpixel_order
	cairo_font_options_set_hint_style
	cairo_font_options_get_hint_style
	cairo_font_options_set_hint_metrics
	cairo_font_options_get_hint_metrics

	cairo_surface_get_font_options

	cairo_ft_font_options_substitute

	cairo_set_font_options
	cairo_get_font_options

   This new font options support allows the application to have much
   more fine-grained control over how fonts are rendered.
   Significantly, it also allows surface backends to have some
   influence over the process. For example, the xlib backend now
   queries existing Xft properties to set font option defaults.

* New function:

	cairo_xlib_surface_set_drawable

  which allows the target drawable for an xlib cairo_surface_t to be
  changed to another with the same format, screen, and display. This
  is necessary in certain double-buffering techniques.

New features
------------
* Sub-pixel text antialiasing is now supported.

Bug fixes
---------
* Fixed assertion failure in cairo_surface_create_similar when
  application commits an error by passing a cairo_format_t rather than
  a cairo_content_t.

* Avoid division by zero in various places (cairo-ft).

* Fix infinite loop when using non-default visuals (cairo-xlib).

* Eliminate segfault in cairo_image_surface_create_from_png_stream.

* Prevent errant sign-extension of masks on 64-bit architectures
  (cairo-xlib and cairo-xcb).

* Other miscellaneous fixes.

Snapshot 0.5.2 (2005-07-18 Carl Worth <cworth@cworth.org>)
==========================================================
API changes
-----------
* New functions for creating patterns of a single color:

	cairo_pattern_create_rgb
	cairo_pattern_create_rgba

* Change cairo_surface_create_similar to accept a new type of
  cairo_content_t rather than cairo_format_t:

	typedef enum _cairo_content {
	    CAIRO_CONTENT_COLOR		= 0x1000,
	    CAIRO_CONTENT_ALPHA		= 0x2000,
	    CAIRO_CONTENT_COLOR_ALPHA	= 0x3000
	} cairo_content_t;

* Add new CAIRO_FORMAT_VALID and CAIRO_CONTENT_VALID macros.

* Remove unused status value:

	CAIRO_STATUS_NO_TARGET_SURFACE

* Add new status values:

	CAIRO_STATUS_INVALID_STATUS

* Require libpixman >= 0.1.5 (for necessary bug fixes)

Bug fixes
---------
* Fix cairo_surface_write_to_png for RGB24 images.

* Fix broken metrics and rendering for bitmap fonts. Add mostly
  useless bitmap glyph transformation.

* Fix glyph caches to not eject entries that might be immediately
  needed, (fixing intermittent crashes when rendering text).

* Fix all memory leaks found by running "make check-valgrind".

ATSUI backend changes
---------------------
* Allow building against < 10.3 SDK.

* Prevent crash on empty strings.

Glitz backend changes
---------------------
* Require glitz >= 0.4.4.

* Use frame buffer objects instead of pbuffers for accelerated
  offscreen drawing.

* Minor improvement to gradient pattern creation.

PostScript backend fixes
------------------------
* Rewrite of the PS backend to generate more interesting output that
  the old big-image implementation.

Win32 backend fixes
-------------------
* Implement glyph path support.

* Fix swap of blue and green values in the fill_rectangles path.

Xlib backend fixes
------------------
* Add optimization to use XCopyArea rather than XRenderComposite when
  transforming only with an integer translation, and using SOURCE
  operator or OVER with a source pattern without alpha.

Snapshot 0.5.1 (2005-06-20 Carl Worth <cworth@cworth.org>)
==========================================================
API changes
-----------
* Removed cairo_status_string(cairo_t*) and add
  cairo_status_to_string(cairo_status_t) in its place. Code using
  cairo_status_string can be ported forward as follows:

	cairo_status (cr);
	->
	cairo_status_to_string (cairo_status (cr));

* Removed the BAD_NESTING restriction which means that two different
  cairo_t objects can now interleave drawing to the same
  cairo_surface_t without causing an error.

* The following functions which previously had a return type of
  cairo_status_t now have a return type of void:

	cairo_pattern_add_color_stop_rgba
	cairo_pattern_set_matrix
	cairo_pattern_get_matrix
	cairo_pattern_set_extend
	cairo_pattern_set_filter

  See discussion of cairo_pattern_status below for more details.

API additions
-------------
* Improved error handling:

	cairo_status_t
	cairo_pattern_status (cairo_pattern_t *pattern);

  This snapshot expands the status-based error handling scheme from
  cairo_t to cairo_path_t and cairo_pattern_t. It also expands the
  scheme so that object-creating functions, (cairo_create,
  cairo_pattern_create_*, cairo_copy_path_*), are now guaranteed to
  not return NULL. Instead, in the case of out-of-memory these
  functions will return a static object with
  status==CAIRO_STATUS_NO_MEMORY. The status can be checked with the
  functions cairo_status and cairo_pattern_status, or by direct
  inspection of the new status field in cairo_path_t.

  Please note that some objects, including cairo_surface_t and all of
  the font-related objects have not been converted to this
  error-handling scheme.

* In addition to the above changes, a new private function has been added:

	_cairo_error

  This function can be used to set a breakpoint in a debugger to make
  it easier to find programming error in cairo-using code. (Currently,
  _cairo_error is called when any error is detected within a cairo_t
  context, but is not called for non-cairo_t errors such as for
  cairo_path_t and cairo_pattern_t).

* Fixed cairo_path_data_t so that its enum is visible to C++ code, (as
  cairo_path_data_type_t).

Performance improvements
------------------------
* Made a minor performance improvement for clipping, (restrict clip
  surface to the new intersected bounds).

* Optimize rendering of a solid source pattern with a pixel-aligned
  rectangular path to use backend clipping rather than rasterization
  and backend compositing.

* Optimize cairo_paint_with_alpha to defer to cairo_paint when alpha
  is 1.0.

Bug fixes
---------
* Fixed memory leak in cairo_copy_path.

* A build fix for non-srcdir builds.

PDF backend fixes
-----------------
* New support for path-based clipping.

* Fix for text rotated to angles other than multiples of π/2.

Win32 backend fixes
-------------------
* Fix for text extents.

Xlib backend
------------
* Implemented a complex workaround for X server bug[*] related to
  Render-based compositing with untransformed, repeating source
  pictures. The workaround uses core Xlib when possible for
  performance, (ie. with CAIRO_OPERATOR_SOURCE or CAIRO_OPERATOR_OVER
  with an opaque source surface), and falls back to the pixman
  image-based compositing otherwise.

  [*] https://bugs.freedesktop.org/show_bug.cgi?id=3566

* Various bug fixes, particularly in the fallback paths.

Snapshot 0.5.0 (2005-05-17 Carl Worth <cworth@cworth.org>)
==========================================================
This is a pretty big, and fairly significant snapshot.  It represents
between 2 and 3 months of solid work from a lot of people on improving
the API as much as possible. I'd like to express my appreciation and
congratulations to everyone who has worked on the big API Shakeup,
(whether in email battles over names, or fixing my silly bugs).

This snapshot will require some effort on the part of users, since
there are a _lot_ of API changes (ie. no cairo program ever written is
safe --- they're all broken now in at least one way). But, in spite of
that, we do encourage everyone to move their code to this snapshot as
soon as possible. And we're doing everything we can think of to make
the transition as smooth as possible.

The idea behind 0.5 is that we've tried to make every good API change
we could want now, and get them all done with. That is, between now
and the 1.0 release of cairo, we expect very few new API changes,
(though some will certainly sneak in). We will have some significant
additions, but the pain of moving code from cairo 0.4 to cairo 0.5
should be a one time experience, and things should be much smoother as
we continue to move toward cairo 1.0.

And with so many changes coming out for the first time in this 0.5
release, we really do need a lot of people trying this out to make
sure the ideas are solid before we freeze the API in preparation for
the 1.0 release.

OK, enough introduction. Here is a (not-quite-complete) description of
the API removals, changes and additions in this snapshot, (compared to
0.4.0)

API removals
============
The following public functions have been removed:

- cairo_set_target_*

	This is a big change. See the description of cairo_create in
	the API changes section for how to deal with this.

- cairo_set_alpha

	Alpha blending hasn't gone away; there's just a much more
	unified rendering model now. Almost all uses of
	cairo_set_alpha will be trivially replaced with
	cairo_set_source_rgba and a few others will be replaced just
	as easily with cairo_paint_with_alpha.

- cairo_show_surface

	Another useful function that we realized was muddling up the
	rendering model. The replacement is quite easy:
	cairo_set_source_surface and cairo_paint.

- cairo_matrix_create
- cairo_matrix_destroy
- cairo_matrix_copy
- cairo_matrix_get_affine

	These functions supported an opaque cairo_matrix_t. We now
	have an exposed cairo_matrix_t structure, so these can be
	dropped.

- cairo_surface_set_repeat
- cairo_surface_set_matrix
- cairo_surface_set_filter

	These properties don't belong on surfaces. If you were using
	them, you'll just want to instead use
	cairo_pattern_create_for_surface and then set these properties
	on the pattern.

- cairo_copy

	This was a confusing function and hopefully nobody will miss
	it. But if you really don't find cairo_save/restore adequate,
	let us know and we have another idea for a potential
	replacement.

And while we're on the subject of removals, we carefully tightened up
the cairo header files so they no longer gratuitously include header
files that are not strictly necessary, (stdio.h, stdint.h, pixman.h,
Xrender.h, etc. and their dependencies). This may lead to some
surprising errors, so keep your eyes open for that.

API changes
===========
Here are some of the API changes that have occurred:

~ cairo_create(void) -> cairo_create(cairo_surface_t *)

	This is the big change that breaks every program. The ability
	to re-target a cairo_t was not particularly useful, but it did
	introduce a lot of muddy semantic questions. To eliminate
	that, cairo_create now requires its target surface to be
	passed in at creation time. This isn't too hard to cope with
	as the typical first operation after cairo_create was often
	cairo_set_target_foo. So the order of those two swap and the
	application instead has cairo_foo_surface_create, then
	cairo_create.

~ cairo_current_* -> cairo_get_*

	We had a strange mixture of cairo_get and cairo_current
	functions. They've all been standardized on cairo_get, (though
	note one is cairo_get_current_point).

~ CAIRO_OPERATOR_SRC -> CAIRO_OPERATOR_SOURCE
~ CAIRO_OPERATOR_OVER_REVERSE -> CAIRO_OPERATOR_DEST_OVER

	Many of the cairo_operator_t symbolic values were renamed to
	reduce the amount of abbreviation. The confusing "OP_REVERSE"
	naming was also changed to use "DEST_OP" instead which is
	easier to read and has wider acceptance in other
	libraries/languages.

~ cairo_set_pattern -> cairo_set_source
~ cairo_set_rgb_color -> cairo_set_source_rgb

	All of the various functions that changed the source
	color/pattern were unified to use cairo_set_source names to
	make the relation more clear.

~ cairo_transform_point		   -> cairo_user_to_device
~ cairo_transform_distance	   -> cairo_user_to_device_distance
~ cairo_inverse_transform_point	   -> cairo_device_to_user
~ cairo_inverse_transform_distance -> cairo_device_to_user_distance

	These names just seemed a lot more clear.

~ cairo_init_clip	-> cairo_reset_clip
~ cairo_concat_matrix	-> cairo_transform

	More abbreviation elimination

~ cairo_current_path	  -> cairo_copy_path
~ cairo_current_path_flat -> cairo_copy_path_flat

	The former mechanism for examining the current path was a
	function that required 3 or 4 callbacks. This was more
	complexity than warranted in most situations. The new
	cairo_copy_path function copies the current path into an
	exposed data structure, and the documentation provides a
	convenient idiom for navigating the path data.

API additions
-------------
+ cairo_paint

	A generalized version of the painting operators cairo_stroke
	and cairo_fill. The cairo_paint call applies the source paint
	everywhere within the current clip region. Very useful for
	clearing a surface to a solid color, or painting an image,
	(see cairo_set_source_surface).

+ cairo_paint_with_alpha

	Like cairo_paint but applying some alpha to the source,
	(making the source paint translucent, eg. to blend an image on
	top of another).

+ cairo_mask

	A more generalized version of cairo_paint_with_alpha which
	allows a pattern to specify the amount of translucence at each
	point rather than using a constant value everywhere.

+ cairo_mask_surface

	A convenience function on cairo_mask for when the mask pattern
	is already contained within a surface.

+ cairo_surface_set_user_data
+ cairo_surface_get_user_data
+ cairo_font_face_set_user_data
+ cairo_font_face_get_user_data

	Associate arbitrary data with a surface or font face for later
	retrieval. Get notified when a surface or font face object is
	destroyed.

+ cairo_surface_finish

	Allows the user to instruct cairo to finish all of its
	operations for a given surface. This provides a safe point for
	doing things such as flushing and closing files that the
	surface may have had open for writing.

+ cairo_fill_preserve
+ cairo_stroke_preserve
+ cairo_clip_preserve

	One interesting change in cairo is that the path is no longer
	part of the graphics state managed by
	cairo_save/restore. This allows functions to construct paths
	without interfering with the graphics state. But it prevents
	the traditional idiom for fill-and-stroke:

		cairo_save; cairo_fill; cairo_restore; cairo_stroke

	Instead we know have alternate versions cairo cairo_fill,
	cairo_stroke, and cairo_clip that preserve the current path
	rather than consuming it. So the idiom now becomes simply:

		cairo_fill_preserve; cairo_stroke

+ cairo_surface_write_to_png
+ cairo_surface_write_to_png_stream

	In place of a single PNG backend, now a surface created
	through any backend (except PDF currently) can be written out
	to a PNG image.

+ cairo_image_surface_create_from_png
+ cairo_image_surface_create_from_png_stream

	And its just as easy to load a PNG image into a surface as well.

+ cairo_append_path

	With the new, exposed path data structure, it's now possible
	to append bulk path data to the current path, (rather than
	issuing a long sequence of cairo_move_to/line_to/curve_to
	function calls).

Xlib and XCB backends
---------------------

Any cairo_format_t and Colormap arguments have been dropped from
cairo_xlib_surface_create. There are also two new
cairo_xlib|xcb_surface_create functions:

	cairo_xlib|xcb_surface_create_for_bitmap
		(Particular for creating A1 surfaces)
	cairo_xlib|xcb_surface_create_with_xrender_format
		(For any other surface types, not described by a Visual*)

All of these surface create functions now accept width and height. In
addition, there are new cairo_xlib|xcb_surface_set_size functions
which must be called each time a window that is underlying a surface
changes size.

Print backends (PS and PDF)
---------------------------
The old FILE* based interfaces have been eliminated. In their place we
have two different functions. One accepts a simple const char
*filename. The other is a more general function which accepts a
callback write function and a void* closure. This should allow the
flexibility needed to hook up with various stream object in many
languages.

In addition, when specifying the surface size during construction, the
units are now device-space units (ie. points) rather than inches. This
provides consistency with all the other surface types and also makes
it much easier to reason about the size of the surface when drawing to
it with the default identity matrix.

Finally, the DPI parameters, which are only needed to control the
quality of fallbacks, have been made optional. Nothing is required
during surface_create (300 DPI is assumed) and
cairo_ps|pdf_surface_set_dpi can be used to set alternate values if
needed.

Font system
-----------
Owen very graciously listened to feedback after the big font rework he
had done for 0.4, and came up with way to improve it even more. In 0.4
there was a cairo_font_t that was always pre-scaled. Now, there is an
unscaled cairo_font_face_t which is easier to construct, (eg. no
scaling matrix required) and work with, (it can be scaled and
transformed after being set on the graphics state). And the font size
manipulation functions are much easier. You can set an explicit size
and read/modify/write the font matrix with:

	cairo_set_font_size
	cairo_get_font_matrix
	cairo_set_font_matrix

(Previously you could only multiply in a scale factor or a matrix.) A
pleasant side effect is that we can (and do) now have a default font
size that is reasonable, as opposed to the old default height of one
device-space unit which was useless until scaled.

Of course, the old pre-scaled font had allowed some performance
benefits when getting many metrics for a font. Those benefits are
still made available through the new cairo_scaled_font_t. And a
cairo_font_face_t can be "promoted" to a cairo_scaled_font_t by
suppling a font_matrix and the desired CTM.

Quartz backend
--------------
Tim Rowley put in the work to bring the Quartz backend back after it
had been disabled in the 0.4.0 snapshot. He was not able to bring back
the function that allows one to create a cairo_font_t from an ATSUI
style:

	cairo_font_t *
	cairo_atsui_font_create (ATSUStyle style);

because he didn't have a test case for it. If you care about this
function, please provide a fairly minimal test and we'll try to bring
it back in an upcoming snapshot.

Snapshot 0.4.0 (2005-03-08 Carl Worth <cworth@cworth.org>)
==========================================================
New documentation
-----------------
Owen Taylor has converted cairo's documentation system to gtk-doc and
has begun some long-needed work on the documentation, which can now be
viewed online here:

	http://cairographics.org/manual/

New backend: win32
------------------
This is the first snapshot to include a functional win32 backend,
(thanks to Owen Taylor). The interface is as follows:

	#include <cairo-win32.h>

	void 
	cairo_set_target_win32 (cairo_t *cr,
				HDC      hdc);

	cairo_surface_t *
	cairo_win32_surface_create (HDC hdc);

	cairo_font_t *
	cairo_win32_font_create_for_logfontw (LOGFONTW       *logfont,
					      cairo_matrix_t *scale);

	cairo_status_t
	cairo_win32_font_select_font (cairo_font_t *font,
				      HDC           hdc);

	void
	cairo_win32_font_done_font (cairo_font_t *font);

	double
	cairo_win32_font_get_scale_factor (cairo_font_t *font);

And see also the documentation at:

http://cairographics.org/manual/cairo-Microsoft-Windows-Backend.html

Disabled backend: quartz
------------------------
Unfortunately, the quartz backend code is currently out of date with
respect to some recent backend interface changes. So, the quartz
backend is disabled in this snapshot.

If the quartz backend is brought up-to-date before the next snapshot,
we would be glad to make a 0.4.1 snapshot that re-enables it, (we do
not expect many more big backend interface changes).

API Changes
-----------
The font system has been revamped, (as Owen Taylor's work with
integrating pango and cairo gave us the first serious usage of the
non-toy font API).

One fundamental, user-visible change is that the cairo_font_t object
now represents a font that is scaled to a particular device
resolution. Further changes are described below.

 cairo.h
 -------
 Removed cairo_font_set_transform and cairo_font_current_transform.

 Added cairo_font_extents and cairo_font_glyph_extents. See
 documentation for details:

 http://cairographics.org/manual/cairo-cairo-t.html#cairo-font-extents

 cairo-ft.h
 ----------
 The cairo_ft_font API changed considerably. Please see the
 documentation for details:

 http://cairographics.org/manual/cairo-FreeType-Fonts.html

Performance
-----------
Make the fast-path clipping (pixel-aligned rectangles) faster.

Add optimization for applying a constant alpha to a pattern.

Optimize gradients that are horizontal or vertical in device space.

Xlib: When RENDER is not available, use image surfaces for
intermediate surfaces rather than xlib surfaces.

Backend-specific changes
------------------------
 Glitz
 -----
 Major update to glitz backend. The output quality should now be just
 as good as the image and xlib backends.

 Track changes to glitz 0.4.0.

 PDF
 ---
 Various improvements to produce more conformant output.

Internals
---------
David Reveman contributed a large re-work of the cairo_pattern_t
implementation, providing cleaner code and more optimization
opportunities.

 Backend interface changes
 -------------------------
 Rework backend interface to accept patterns, not surfaces for source
 and mask.

 Remove set_matrix, set_filter, and set_repeat functions.

 More sophisticated backend interface for image fallbacks,
 ({acquire,release}_{source,dest}_image() and clone_similar).

Bug fixes
---------
Only install header files for backends that have been compiled.

Fixed some rounding errors leading to incorrectly placed glyphs.

Many other minor fixes.

Snapshot 0.3.0 (2005-01-21 Carl Worth <cworth@cworth.org>)
==========================================================
Major API changes
-----------------
1) The public header files will no longer be directly installed into
   the system include directory. They will now be installed in a
   subdirectory named "cairo", (eg. in /usr/include/cairo rather than
   in /usr/include).

   As always, the easiest way for applications to discover the
   location of the header file is to let pkg-config generate the
   necessary -I CFLAGS and -L/-l LDFLAGS. For example:

	cc `pkg-config --cflags --libs cairo` -o foo foo.c

   IMPORTANT: Users with old versions of cairo installed will need to
              manually remove cairo.h and cairo-features.h from the
              system include directories in order to prevent the old
              headers from being used in preference to the new ones.

2) The backend-specific portions of the old monolithic cairo.h have
   been split out into individual public header files. The new files
   are:

	cairo-atsui.h
        cairo-ft.h
        cairo-glitz.h
        cairo-pdf.h
        cairo-png.h
        cairo-ps.h
	cairo-quartz.h
        cairo-xcb.h
        cairo-xlib.h

   Applications will need to be modified to explicitly include the new
   header files where appropriate.

3) There are two new graphics backends in this snapshot, a PDF
   backend, and a Quartz backend. There is also one new font backend,
   ATSUI.

PDF backend
-----------
Kristian Høgsberg has contributed a new backend to allow cairo-based
applications to generate PDF output. The interface for creating a PDF
surface is similar to that of the PS backend, as can be seen in
cairo-pdf.h:

	void
	cairo_set_target_pdf (cairo_t	*cr,
			      FILE	*file,
			      double	width_inches,
			      double	height_inches,
			      double	x_pixels_per_inch,
			      double	y_pixels_per_inch);

	cairo_surface_t *
	cairo_pdf_surface_create (FILE		*file,
				  double	width_inches,
				  double	height_inches,
				  double	x_pixels_per_inch,
				  double	y_pixels_per_inch);

Once a PDF surface has been created, applications can draw to it as
any other cairo surface.

This code is still a bit rough around the edges, and does not yet
support clipping, surface patterns, or transparent gradients.  Text
only works with TrueType fonts at this point and only black text is
supported.  Also, the size of the generated PDF files is currently
quite big.

Kristian is still actively developing this backend, so watch this
space for future progress.

Quartz backend
--------------
Calum Robinson has contributed a new backend to allow cairo
applications to target native Mac OS X windows through the Quartz
API. Geoff Norton integrated this backend into the current
configure-based build system, while Calum also provided Xcode build
support in the separate "macosx" module available in CVS.

The new interface, available in cairo-quartz.h, is as follows:

	void
	cairo_set_target_quartz_context (cairo_t	*cr,
					 CGContextRef	context,
					 int		width,
					 int		height);

	cairo_surface_t *
	cairo_quartz_surface_create (CGContextRef context,
				     int	  width,
				     int	  height);

There is an example program available in CVS in cairo-demo/quartz. It
is a port of Keith Packard's fdclock program originally written for
the xlib backend. A screenshot of this program running on Mac OS X is
available here:

	http://cairographics.org/~cworth/images/fdclock-quartz.png

ATSUI font backend
------------------
This new font backend complements the Quartz backend by allowing
applications to use native font selection on Mac OS X. The interface
is a single new function:

	cairo_font_t *
	cairo_atsui_font_create (ATSUStyle style);

Minor API changes
-----------------
Prototype for non-existent function "cairo_ft_font_destroy" removed.

Now depends on libpixman 0.1.2 or newer, (0.1.3 is being released
concurrently and has some useful performance improvements).

Default paint color is now opaque black, (was opaque white). Default
background color is transparent (as before).

Renamed "struct cairo" to "struct _cairo" to free up the word "cairo"
from the C++ identifier name space.

Functions returning multiple return values through provided pointers,
(cairo_matrix_get_affine, cairo_current_point, and
cairo_current_color_rgb), will now accept NULL for values the user
wants to ignore.

CAIRO_HAS_FREETYPE_FONT has now been renamed to CAIRO_HAS_FT_FONT.

Performance improvements
------------------------
Alexander Larsson provided some fantastic performance improvements
yielding a 10000% performance improvement in his application, (when
also including his performance work in libpixman-0.1.3). These include

 * Fixed handling of cache misses.

 * Creating intermediate clip surfaces at the minimal size required.

 * Eliminating roundtrips when creating intermediate Xlib surfaces.

Implementation
--------------
Major re-work of font metrics system by Keith Packard. Font metrics
should now be much more reliable.

Glitz backend
-------------
Updated for glitz-0.3.0.
Bug fixes in reference counting.

Test suite
----------
New tests for cache crashing, rotating text, improper filling of
complex polygons, and leaky rasterization.

Bug fixes
---------
Fixed assertion failure when selecting the same font multiple times in
sequence.

Fixed reference counting so cache_destroy functions work.

Remove unintended copyright statement from files generated with
PostScript backend.

Fixed to eliminate new warnings from gcc 3.4 and gcc 4.

Snapshot 0.2.0 (2004-10-27 Carl Worth <cworth@cworth.org>)
===========================================================
New license: LGPL/MPL
---------------------
The most significant news with this release is that the license of
cairo has changed. It is now dual-licensed under the LGPL and the
MPL. For details see the COPYING file as well as COPYING-LGPL-2.1 and
COPYING-MPL-1.1.

I express my thanks to everyone involved in the license change process
for their patience and support!

New font and glyph internals
----------------------------
Graydon Hoare has put a tremendous amount of work into new internals
for handling fonts and glyphs, including caches where appropriate.
This work has no impact on the user-level API, but should result in
great performance improvements for applications using text.

New test suite
--------------
This snapshot of cairo includes a (small) test suite in
cairo/test. The tests can be run with "make check". The test suite was
designed to make it very easy to add new tests, and we hope to see
many contributions here. As you find bugs, please try adding a minimal
test case to the suite, and submit it with the bug report to the
cairo@cairographics.org mailing list. This will make it much easier
for us to track progress in fixing bugs.

New name for glitz backend
--------------------------
The gl backend has now been renamed to the glitz backend. This means
that the following names have changed:

	CAIRO_HAS_GL_SURFACE    -> CAIRO_HAS_GLITZ_SURFACE
	cairo_set_target_gl     -> cairo_set_target_glitz
	cairo_gl_surface_create -> cairo_glitz_surface_create

This change obviously breaks backwards compatibility for applications
using the old gl backend.

Up-to-date with latest glitz snapshots
--------------------------------------
This snapshot of cairo is now up to date with the latest glitz
snapshot, (currently 0.2.3). We know that the latest cairo and glitz
snapshots have been incompatible for a very long time. We've finally
fixed that now and we're determined to not let that happen again.

Revert some tessellation regression bugs
----------------------------------------
People that have been seeing some tessellation bugs, (eg. leaked
fills), in the CVS version of cairo may have better luck with this
release. A change since the last snapshot was identified to trigger
some of these bugs and was reverted before making the snapshot. The
behavior should be the same as the previous (0.1.23) snapshot.

Miscellaneous changes
---------------------
Changed CAIRO_FILTER_DEFAULT to CAIRO_FILTER_BEST to make gradients
easier.

Track XCB API change regarding iterators.

Various bug fixes
-----------------
Fix calculation of required number of vertices for pen.

Fix to avoid zero-dimensioned pixmaps.

Fix broken sort of pen vertices.

Fix bug when cairo_show_text called with a NULL string.

Fix clipping bugs.

Fix bug in computing image length with XCB.

Fix infinite loop bug in cairo_arc.

Fix memory management interactions with libpixman.

Snapshot 0.1.23 (2004-05-11 Carl Worth <cworth@isi.edu>)
========================================================
Fixes for gcc 3.4
-----------------
Fix prototype mismatches so that cairo can be built by gcc 3.4.

Updates to track glitz
----------------------
Various fixes to support the latest glitz snapshot (0.1.2).

Gradient updates
----------------
Radial gradients now support both inner and outer circles.
Transformed linear gradients are now properly handled.
Fixes for extend type reflect.

Glitz updates
-------------
Converted shading routines to use fixed point values and introduced a
shading operator structure for more efficient shading calculations.
Support compositing with mask surface when mask is solid or
multi-texturing is available.

PNG backend cleanups
--------------------
Fix output to properly compensate for pre-multiplied alpha format in cairo.
Add support for A8 and A1 image formats.

Bug fixes
---------
Avoid crash or infinite loop on null strings and degeneratively short
splines.

New? bugs in cairo_clip
-----------------------
There are some fairly serious bugs in cairo_clip. It is sometimes
causing an incorrect result. And even when it does work, it is
sometimes so slow as to be unusable. Some of these bugs may not be
new, (indeed cairo_clip has only ever had a braindead-slow
implementation), but I think they're worth mentioning here.

Snapshot 0.1.22 (2004-04-16 Carl Worth <cworth@isi.edu>)
========================================================
Cairo was updated to track the changes in libpixman, and now depends
on libpixman version 0.1.1.

Snapshot 0.1.21 (2004-04-09 David Reveman <c99drn@cs.umu.se>)
=============================================================
New OpenGL backend
------------------
The OpenGL backend provides hardware accelerated output for
X11 and OS X. The significant new functions are:

	cairo_set_target_gl
	cairo_gl_surface_create

Automatic detection of available backends
-----------------------------------------
The configure script now automatically detect what backends are
available, (use ./configure --disable-`backend' to prevent
compilation of specific backends).

Snapshot 0.1.20 (2004-04-06 Carl Worth <cworth@isi.edu>)
========================================================
New pattern API
---------------
David Reveman has contributed a new pattern API which enable linear
and radial gradient patterns in addition to the original surface-based
patterns. The significant new top-level functions are:

	cairo_pattern_create_linear
	cairo_pattern_create_radial
	cairo_pattern_create_for_surface
	cairo_pattern_add_color_stop
	cairo_set_pattern

Any code using the old cairo_set_pattern, (which accepted a
cairo_surface_t rather than a cairo_pattern_t), will need to be
updated.

Update to XCB backend
---------------------
The XCB backend is now enabled by default, (use ./configure
--disable-xcb to turn it off).

Faster clipping
---------------
Graydon Hoare has added optimizations that make cairo_clip much faster
when the path is a pixel-aligned, rectangular region.

Bug fixes.

Snapshot 0.1.19 (2004-02-24 Carl Worth <cworth@isi.edu>)
========================================================
New PNG backend
---------------
Olivier Andrieu contributed a new PNG backend. It builds on the
existing image backend to make it easy to render "directly" to a
.png file. The user never needs to deal with the actual image
buffer. The significant new functions are:

	cairo_set_target_png
	cairo_png_surface_create

The PNG backend is not enabled by default so that by default there is
not a new dependency on libpng. Use ./configure --enable-png to enable
this backend.

Snapshot 0.1.18 (2004-02-17 Carl Worth <cworth@isi.edu>)
========================================================
Path query functionality
------------------------
It's now possible to query the current path. The two new functions
are:

	cairo_current_path
	cairo_current_path_flat

Each function accepts a number of callback functions that will be
called for each element in the path (move_to, line_to, curve_to,
close_path). The cairo_current_path_flat function does not accept a
curve_to callback. Instead, all curved portions of the path will be
converted to line segments, (within the current tolerance value). This
can be handy for doing things like text-on-path without having to
manually interpolate Bézier splines.

New XCB backend
---------------
Jamey Sharp has contributed a second X backend that uses the new, lean
XCB library rather than Xlib. It cannot currently be compiled at the
same time as the Xlib backend. See ./configure --enable-xcb.

Build fixes for cygwin.

Bug fixes.

Snapshot 0.1.17 (2003-12-16 Carl Worth <cworth@isi.edu>)
========================================================

Better text support
-------------------
This snapshot provides much better text support by implementing the
following four functions:

        cairo_text_extents
        cairo_glyph_extents
        cairo_text_path
        cairo_glyph_path

The text/glyph_extents functions can be used to determine the bounding
box (and advance) for text as if drawn by show_text/glyphs.

The text/glyph_path objects functions place text shapes on the current
path, where they can be subsequently manipulated. For example,
following these functions with cairo_stroke allows outline text to be
drawn. Calling cairo_clip allows clipping to a text-shaped region.

Combined dependencies
---------------------
The cairo core now depends only on the libpixman library. This single
library replaces the three previous libraries libic, libpixregion, and
slim. Thanks to Dave Beckett <dave.beckett@bristol.ac.uk> for all of
the heavy lifting with this renaming effort.

Conditional compilation of backends
-----------------------------------
Cairo now allows optional backends to be disabled at compile time. The
following options may now be passed to the configure script:

	--disable-xlib
	--disable-ps

Note that the first option is a change from the old --without-x option
which will no longer have any effect.

OS X supported - several byte-order issues resolved
---------------------------------------------------
Cairo has now been successfully compiled under OS X. Testing revealed
that there were some byte-order problems in the PostScript backend and
the PNG generation in the demos. These have now been resolved.

2003-10
=======
Graydon Hoare <graydon@redhat.com> implemented the first real text
support using Freetype/fontconfig, (previous versions of cairo used
Xft and could only draw text when using an X backend).

2003-09
=======
Graydon Hoare <graydon@redhat.com> added the first real support for
running cairo with a non-render-aware X server.

Jamey Sharp <jamey@minilop.net> virtualized the backend font and
surface interfaces in September, 2003.

2003-06
=======
Xr is renamed cairo to avoid confusion since it no longer had a strict
dependence on X.

2003-05
=======
A new image surface backend is added to Xr. Keith Packard
<keithp@keithp.com> wrote the image compositing code in libic that is
used for the image_surface backend. This code was originally written
as the software fallback for the render extension within the X
server.

2002-06
=======
Carl Worth <cworth@isi.edu> wrote the first lines of Xr, after Keith
Packard <keithp@keithp.com> proposed the plan for a stateful drawing
library in C providing a PostScript-like rendering model.