[cairo-commit] NEWS

[Carl Worth]

 NEWS |  252 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 252 insertions(+)

New commits:
commit f09f02a6e82df0efb66696fca857a412e7d12672
Author: Carl Worth <cworth at cworth.org>
Date:   Tue Oct 30 21:57:47 2007 -0700

    Add notes for 1.5.2 snapshot

diff --git a/NEWS b/NEWS
index 9761028..b2e5b6d 100644
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,255 @@
+Snapshot 1.5.2 (2007-10-30 Carl Worth <cworth at cworth.org>)
+==========================================================
+This is the first snapshot in cairo's unstable 1.5 series. It comes 4
+months after the 1.4.10 release. This snapshot includes significant
+improvements to PDF and PostScript output, which is one of the things
+in which we're most interested in getting feedback. There are a couple
+of minor API additions, and several optimizations, (primarily in the
+"print/vector" backends). And there are dozens of bug fixes and
+robustness improvements.
+
+New dependency on external pixman library
+-----------------------------------------
+A significant change in this snapshot compared to all previous cairo
+releases is that cairo now depends on an external "pixman" library for
+its software rendering. Previously this same code was compiled
+internally as part of cairo, but now the code is separate so that both
+cairo and the X server can now share common code, (thanks very much to
+Søren Sandmann for his work on separating pixman and maintaining it).
+
+So users will need to acquire and build pixman before being able to
+build cairo. The current release is 0.9.6 and can be obtained from
+here:
+
+	http://cairographics.org/releases/pixman-0.9.6.tar.gz
+
+ which can be verified with:
+
+	http://cairographics.org/releases/pixman-0.9.6.tar.gz.sha1
+	66f01a682c64403a3d7a855ba5aa609ed93bcb9e  pixman-0.9.6.tar.gz
+
+	http://cairographics.org/releases/pixman-0.9.6.tar.gz.sha1.asc
+	(signed by Carl Worth)
+
+Major PDF/PostScript improvements
+---------------------------------
+Adrian Johnson has done some long-awaited work to make cairo's PDF and
+PostScript output more interesting than ever before. First, many
+operations that previously triggered image fallbacks will now be
+rendered as native vectors. These operations include:
+
+	PDF: cairo_push_group, cairo_surface_create_similar,
+	cairo_mask, A8/A1 surface sources, repeating/reflecting linear
+	gradients.
+
+	PostScript: cairo_push_group, cairo_surface_create_similar,
+	gradients, bilevel alpha masks, (for example, all values either 0 or
+	255 for an A8 mask).
+
+Not only that, but when an image fallback is required, it will now be
+limited to only the necessary region. For example, a tiny translucent
+image overlaying a small portion of text would previously caused an
+entire PostScript page to be rendered as a giant image. Now, the
+majority of that page will be nice text, and there will only be a tiny
+image in the output.
+
+Additionally, the PostScript output now carefully encodes text so that
+if it is subsequently converted to PDF, the text will be
+selectable.
+
+This is very exciting progress, and we're hoping to hear from users
+during the 1.5 series about how things have improved, (for example,
+inkscape users doing cairo-based PDF export: please let us know how
+things look). And feel free to pass your thanks along to Adrian for his excellent work.
+
+NOTE: This much improved PDF output makes more sophisticated use of
+functionality in the PDF specification. This means that cairo's output
+will sometimes expose bugs in some free software PDF viewers, (evince,
+poppler, and xpdf, for example), that are not yet ready for such PDF
+files. We're working with the poppler maintainers to get these bugs
+fixed as quickly as possible. In the meantime, please double-check
+with other PDF viewers if cairo-generated PDF files are not being
+rendered correctly. It may be due to a bug in the viewer rather than
+in the PDF file that cairo has created.
+
+Robustness improvements
+-----------------------
+Chris Wilson has made the largest contribution by far to cairo 1.5.2,
+(in number of commits). His more than 150 commits include a huge
+number of fixes to increase cairo's robustness. These fixes make cairo
+more robust against invalid and degenerate input, (NaN, empty path,
+etc.), against size-0 malloc calls, against memory leaks on
+error-recovery paths, and against other failures during error
+handling. He also implemented atomic operations to cairo, and used
+them to fix cairo's previously non-thread-safe reference counting,
+again improving robustness.
+
+Chris has put a tremendous amount of time and effort into writing
+analysis tools for this work, and in running those tools and fixing
+the problems they report. We're very grateful for this work, and hope
+that all cairo users appreciate the more robust implementation that
+results from it.
+
+This work is largely thankless, so it might make sense to notice
+sometime that cairo has been running quite smoothly for you, and when
+you do, send a quick "thank you" off to Chris Wilson, since it
+is all definitely running smoother thanks to his work.
+
+New API
+-------
+There are no major additions to cairo's core API. The only new,
+generic functions are:
+
+	void
+	cairo_surface_copy_page (cairo_surface_t *surface);
+
+	void
+	cairo_surface_show_page (cairo_surface_t *surface);
+
+which can now be used much more conveniently than the existing
+cairo_copy_page and cairo_show_page functions in some
+situations. These functions act identically, but require only a
+cairo_surface_t* and not a cairo_t*.
+
+All other API additions are specific to particular backends.
+
+New cairo-win32 API (new font face function and "win32 printing" surface)
+-------------------------------------------------------------------------
+There is a new function for creating a win32 font face for both a
+logfontw and an hfont together. This complements the existing
+functions for creating a font face from one or the other:
+
+	cairo_font_face_t *
+	cairo_win32_font_face_create_for_logfontw_hfont (LOGFONTW *logfont,
+							 HFONT font);
+
+There is also a new "win32 printing" surface:
+
+	cairo_surface_t *
+	cairo_win32_printing_surface_create (HDC hdc);
+
+This interface looks identical to the original
+cairo_win32_surface_create, (both accept and HDC), but the behavior of
+this new surface is very different. It should only be called with a
+printing DC, and will result in all drawing commands being stored into
+a meta-surface and emitted after each page is complete, with analysis
+to do as minimal image-based fallbacks as necessary. The behavior and
+implementation shares much with the PDF and PostScript backends.
+
+New cairo-ps API (EPS and PostScript level control)
+---------------------------------------------------
+An often requested feature has been the ability to generate
+Encapsulated PostScript (EPS) with cairo. We have that now with the
+following very simple API. Just do cairo_ps_surface_create as usual
+then call this function with a true value:
+
+	void
+	cairo_ps_surface_set_eps (cairo_surface_t       *surface,
+				  cairo_bool_t           eps);
+
+[NOTE: As always with snapshots, it's possible---though not very
+likely---that the API could still be modified before a final
+release. For example, this is the first public cairo function that
+accepts a Boolean parameter. I'm generally opposed to Boolean
+parameters, but this is probably the one case where I'm willing to
+accept one, (namely a "set" function that accepts a single Boolean).]
+
+Also, it is now possible to control what PostScript level to target,
+(either level 2 or level 3), with the following new API:
+
+	typedef enum _cairo_ps_level {
+	    CAIRO_PS_LEVEL_2,
+	    CAIRO_PS_LEVEL_3
+	} cairo_ps_level_t;
+
+	void
+	cairo_ps_surface_restrict_to_level (cairo_surface_t    *surface,
+					    cairo_ps_level_t    level);
+
+	void
+	cairo_ps_get_levels (cairo_ps_level_t const  **levels,
+			     int                      *num_levels);
+
+	const char *
+	cairo_ps_level_to_string (cairo_ps_level_t level);
+
+Improvement for cairo-quartz
+----------------------------
+Brian Ewins had contributed several improvements to cairo-quartz. These
+include an implementation of EXTEND_NONE for linear and radial
+gradients, (so this extend mode will no longer trigger image fallbacks
+for these gradients), as well as native surface-mask clipping, (only
+on OS X 10.4+ where the CGContextClipToMask function is available).
+
+He also fixed a semantic mismatch between cairo and quartz for dashing
+with an odd number of entries in the dash array.
+
+We're grateful for Brian since not many quartz-specific improvements
+to cairo would be happening without him.
+
+Optimizations
+-------------
+Optimize SVG output for when the same path is both filled and stroked,
+and avoid unnecessary identity matrix in SVG output. (Emmanuel Pacaud).
+
+Optimize PS output to take less space (Ken Herron).
+
+Make PS output more compliant with DSC recommendations (avoid initclip
+and copy_page) (Adrian Johnson).
+
+Make PDF output more compact (Adrian Johnson).
+
+Release glyph surfaces after uploading them to the X server, (should
+save some memory for many xlib-using cairo application). (Behdad
+Esfahbod).
+
+Optimize cairo-win32 to use fewer GDI objects (Vladimir Vukicevic).
+
+win32-printing: Avoid falling back to images when alpha == 255
+everywhere. (Adrian Johnson).
+
+win32-printing: Avoid falling back for cairo_push_group and
+cairo_surface_create_similar. (Adrian Johnson)
+
+Bug fixes
+---------
+Avoid potential integer overflows when allocating large buffers
+(Vladimir Vukicevic).
+
+Preparations to allow the 16.16 fixed-point format to change to
+24.8 (Vladimir Vukicevic).
+
+Fix bugs for unsupported X server visuals (rgb565, rgb555, bgr888, and
+abgr8888). (Carl Worth and Vladimir Vukicevic)
+
+Fix bugs in PDF gradients (Adrian Johnson).
+
+Fix cairo-xlib to build without requiring Xrender header
+files (Behdad Esfahbod).
+
+Make cairo more resilient in the case of glyphs not being available in
+the current font. (Behdad Esfahbod)
+
+Prevent crashes when both atsui and ft font backends are compiled in
+(Brian Ewins).
+
+Make font subsetting code more robust against fonts that don't include
+optional tables (Adrian Johnson).
+
+Fix CFF subsetting bug, (which manifested by generating PDF files that
+Apple's Preview viewer could not read) (Adrian Johnson).
+
+Fixed error handling for quartz and ATSUI backends (Brian Ewins).
+
+Avoid rounding problems by pre-transforming to avoid integer-only
+restrictions on transformation in GDI (Adrian Johnson).
+
+Fixed an obscure bug (#7245) computing extents for some stroked
+paths (Carl Worth).
+
+Fix crashes due to extreme transformation of the pen, (seems to show
+up in many .swf files for some reason) (Carl Worth).
+
 Release 1.4.10 (2007-06-27 Carl Worth <cworth at cworth.org>)
 ==========================================================
 This is the fifth update in cairo's stable 1.4 series. It comes