Pango-1.17.0 released [unstable]

[Behdad Esfahbod <besfahbo redhat com>]

Pango-1.17.0 is now available for download at:

  http://download.gnome.org/sources/pango/1.17/
or
  ftp://ftp.gtk.org/pub/pango/1.17

c1b9b2e236a0d5fe208b532a4a792e7a  pango-1.17.0.tar.bz2
7326429bb60bf02685aeee4b3ffbf64a  pango-1.17.0.tar.gz

This is the first development release in what seems to be a exciting
cycle in Pango development, leading to Pango-1.18.0, which
will be released just in time for GNOME-2.20.


Notes:

 * This is unstable development release. While it has had
   fairly extensive testing, there are likely bugs
   remaining to be found. This release should not be used
   in production.

 * Installing this version will overwrite your existing
   copy of Pango. If you have problems, you'll need
   to reinstall Pango-1.16.x

 * Bugs should be reported to http://bugzilla.gnome.org.

About Pango
===========

Pango is a library for layout and rendering of text, with an emphasis
on internationalization. Pango can be used anywhere that text layout
is needed, though most of the work on Pango so far has been done in
the context of the GTK+ widget toolkit. Pango forms the core of text
and font handling for GTK+-2.x.

Pango is designed to be modular; the core Pango layout engine can
be used with different font backends. There are three basic backends,
with multiple options for rendering with each.

 - Client side fonts using the FreeType and fontconfig libraries.
   Rendering can be with with Cairo or Xft libraries, or directly
   to an in-memory buffer with no additional libraries.

 - Native fonts on Microsoft Windows using Uniscribe for
   complex-text handling. Rendering can be done via Cairo or
   directly using the native Win32 API.

 - Native fonts on MacOS X, rendering via Cairo.

The integration of Pango with Cairo (http://cairographics.org)
provides a complete solution with high quality text handling
and graphics rendering.

Dynamically loaded modules then handle text layout for particular
combinations of script and font backend. Pango ships with a wide
selection of modules, including modules for Hebrew, Arabic,
Hangul, Thai, and a number of Indic scripts. Virtually all of the
world's major scripts are supported.

As well as the low level layout rendering routines, Pango includes
PangoLayout, a high level driver for laying out entire blocks of text,
and routines to assist in editing internationalized text.

More information about Pango is available from http://www.pango.org/.
Bugs should be reported to http://bugzilla.gnome.org.

Pango 1.17 depends on version 2.12.0 or newer of the GLib
library and version 1.2.6 or newer of the cairo library (if the
cairo backend is desired); more information about GLib and cairo
can be found at http://www.gtk.org/ and http://cairographics.org/
respectively.

Overview of changes between 1.16.4 and 1.17.0
==============================================

General:

- Text justification.  A simple justification algorithm is implemented
  that tries to justify by expanding spaces in the line, and if none
  found, by adjust letter spacing.  [Based on patch by Mathias
  Hasselmann]

- The pango_script_get_sample_language() function is modified to use
  the value of environment variables PANGO_LANGUAGE or LANGUAGE
  (checked in that order) to make guess better languages for scripts.
  The env var should be a list of language tags, like "en:fa" for
  example where in effect makes Pango choose Persian (fa) fonts
  instead of Arabic (ar) fonts when a run of text in the Arabic script
  is found in an otherwise non-Arabic layout.

  This trick is also useful for East Asian languages.  For example a
  Japanese user that cannot set her primary language to Japanese can
  still set PANGO_LANGUAGE="ja" and Pango will map CJK characters to
  Japanese.

  The LANGUAGE env var is a standard gettext variable listing
  languages the user wants to receive UI translated messages in.
  However, since most packages don't provide separate English
  translations, setting LANGUAGE="en:ja" doesn't have the intended
  effect and UI messages will be shown in Japanese.  For these
  situations one can use LANGUAGE="en:C:ja".  Pango skips the special
  language tag 'C'.

- Simplified embedded-shape rendering with pangocairo backends do.
  [Richard Hult]

- New header file: Moved PangoLanguage APIs into its own header
  pango-language.h, which is included from pango-types.h.

- ATSUI backend now lists synthesized italic faces like other

- Misc optimizations and fixes.

OpenType Layout Engine Improvements:

- Vertical glyph variants are not selected in vertical text if the
  font supports them.

- Instead of hardcoded OpenType script tag in each module, and using
  Default Language System unconditionally, Pango will now find and use
  the script/lang-sys pair that best matches the detected script and
  language of a run of text.  Moreover, it also applies the OpenType
  'locl' feature.
  
  These, plus the PANGO_LANGUAGE env var, give font designers and
  users lots of options to provide/choose language-specific glyph
  variants.
  
  Only basic, arabic, and syriac modules updated to take advantage of
  the new support so far.

New pango-view command line options:

        --align
        --justify
        --language

Public API Changes:

- New public pangocairo API:

        PangoCairoShapeRendererFunc
        pango_cairo_context_set_shape_renderer() 
        pango_cairo_context_get_shape_renderer() 

  These are used by the default pangocairo renderer to render shape
  attributes (see examples/cairoshape.c).  Cairo-based PangoRenderer
  implementations outside Pango may want to implement the draw_shape()
  method similarly to provide compatibility with these new APIs.  (See
  bug #437533 for GdkPangoRenderer for example.)

- Other public API changes:

        New is_expandable_space member in PangoLogAttr
        New macro PANGO_UNITS_ROUND()

- New OpenType engine API.  These are engine API, for use by Pango
  modules, and typically need not to be bound by language bindings:

        PANGO_OT_NO_FEATURE
        PANGO_OT_NO_SCRIPT
        PANGO_OT_TAG_DEFAULT_SCRIPT
        PANGO_OT_TAG_DEFAULT_LANGUAGE
        PangoOTFeatureMap
        PangoOTRulesetDescription
        pango_ot_ruleset_get_for()
        pango_ot_ruleset_new_for()
        pango_ot_ruleset_maybe_add_feature()
        pango_ot_ruleset_maybe_add_features()
        pango_ot_ruleset_description_hash()
        pango_ot_ruleset_description_equal()
        pango_ot_ruleset_description_copy()
        pango_ot_ruleset_description_free()
        pango_ot_tag_from_script()
        pango_ot_tag_to_script()
        pango_ot_tag_from_language()
        pango_ot_tag_to_language()

- Bugs fixed in this release:

        Bug 64538 â pango_layout_set_justify() doesn't work
        Bug 325714 â Pango should respect $LANGUAGE
        Bug 414264 â Pango vertical writing support is different with real
                     CJK usage.
        Bug 416515 â Time is not aligned with date on vertical panel
        Bug 429397 â Updated MS Mincho/Gothic are not listed in font dialog
                     properly on Vista/
        Bug 433805 â [Atsui] Approximate char/digit width width often 0
                     (worked around)
        Bug 434160 - [atsui] Italic versions of some faces can't be created
        Bug 435709 â pango_cairo_context_[sg]et_shape_renderer()
        Bug 355789 â Pango misaligns word-wrapped text due to trailing
                     whitespace
        Bug 436154 â Error building the pango.modules file while cross
                     compiling
        Bug 436988 â Adding PangoScript to PangoAnalysis
        Bug 437534 â pango_language_includes_script is buggy

14 May 2007
Behdad Esfahbod