Overview of changes leading to 3.3.1
Monday, January 31, 2022
====================================
- Fix heap-use-after-free in harfbuzz-subset introduced in previous release.
  (Garret Rieger)


Overview of changes leading to 3.3.0
Monday, January 31, 2022
====================================
- Improved documentation. (Matthias Clasen)
- Internal code cleanup, using C++ standard library more. (Behdad Esfahbod)
- The low 16-bits of face index will be used by hb_face_create() to select a
  face inside a font collection file format, while the high 16-bits will be
  used by hb_font_create() to load the named instance. (Behdad Esfahbod)
- Glyph positions and other font metrics now apply synthetic slant set by
  hb_font_set_synthetic_slant(), for improved positioning for synthetically
  slanted fonts. (Behdad Esfahbod)
- Fixed unintentional locale dependency in hb_variation_to_string() for decimal
  point representation. (Matthias Clasen)
- When applying pair positioning (kerning) the positioning value is split
  between the two sides of the pair for improved cursor positioning between
  such pairs. (Behdad Esfahbod)
- Introduced new HB_GLYPH_FLAG_UNSAFE_TO_CONCAT, to be used in conjunction
  with HB_GLYPH_FLAG_UNSAFE_TO_BREAK for optimizing re-shaping during line
  breaking. Check the documentation for further details. (Behdad Esfahbod)
- Improved handling of macrolanguages when mapping BCP 47 codes to OpenType
  tags. (David Corbett)

- New API:
+HB_GLYPH_FLAG_UNSAFE_TO_CONCAT
+hb_segment_properties_overlay()
+hb_buffer_create_similar()
+hb_font_set_synthetic_slant()
+hb_font_get_synthetic_slant()
+hb_font_get_var_coords_design()


Overview of changes leading to 3.2.0
Friday, November 26, 2021
====================================
“harfbuzz” library improvements:
- Fixed shaping of Apple Color Emoji flags in right-to-left context. (Behdad Esfahbod)
- Fixed positioning of CFF fonts in HB_TINY profile. (Behdad Esfahbod)
- OpenType 1.9 language tags update. (David Corbett)
- Add HB_NO_VERTICAL config option.
- Add HB_CONFIG_OVERRIDE_H for easier configuration. (Behdad Esfahbod)

“harfbuzz-subset” library improvements:
- Improved packing of cmap, loca, and Ligature tables. (Garret Rieger)
- Significantly improved overflow-resolution strategy in the repacker. (Garret Rieger)


Overview of changes leading to 3.1.2
Friday, November 26, 2021
====================================
- hb-shape / hb-view: revert treating text on the commandline as single
  paragraph (was introduced in 3.0.0); add new --single-par to do that.
  (Behdad Esfahbod)
- Subsetter bug fixes. (Garret Rieger, Qunxin Liu, Behdad Esfahbod)


Overview of changes leading to 3.1.1
Wednesday, November 8, 2021
====================================
- Work around GCC cast-align error/warning on some platforms. (Behdad Esfahbod)
- Documentation improvements. (Matthias Clasen)


Overview of changes leading to 3.1.0
Wednesday, November 3, 2021
====================================
- Better offset-overflow handling in the subsetter library. (Garret Rieger)
- Improved Unicode 14 properties in the USE shaper, and various other USE
  shaper fixes. (David Corbett)
- MATH and COLR v1 tables subsetting support, and various other subsetter fixes.
  (Qunxin Liu)
- Support for Pwo Karen / Ason Chin medial la. (Simon Cozens)
- Apply GPOS positioning when substituting with morx table, if kerx is missing.
  (Behdad Esfahbod)
- Apply calt and clig features across syllable boundaries in Indic shaper.
  (Behdad Esfahbod)
- meson option for enabling Graphite 2 has been renamed to graphite2.
- Build and documentation fixes.

- New API:
+hb_buffer_set_not_found_glyph()
+hb_buffer_get_not_found_glyph()


Overview of changes leading to 3.0.0
Friday, September 17, 2021
====================================
- Unicode 14.0 support (David Corbett).
- The hb-subset API and the harfbuzz-subset library's ABI are now declared
  stable. The harfbuzz-subset library would not have been possible without the
  work of Garret Rieger and Qunxin Liu from Google Fonts, and the earlier work
  of Michiharu Ariza from Adobe.
- The hb-style API is now stable and no longer experimental.

- New API:
+hb_style_tag_t
+hb_style_get_value()
+hb_subset_input_t
+hb_subset_flags_t
+hb_subset_sets_t
+hb_subset_input_create_or_fail()
+hb_subset_input_reference()
+hb_subset_input_destroy()
+hb_subset_input_set_user_data()
+hb_subset_input_get_user_data()
+hb_subset_input_unicode_set()
+hb_subset_input_glyph_set()
+hb_subset_input_set()
+hb_subset_input_get_flags()
+hb_subset_input_set_flags()
+hb_subset_or_fail()

- Removed old unstable harfbuzz-subset API:
-hb_subset_input_nameid_set()
-hb_subset_input_namelangid_set()
-hb_subset_input_layout_features_set()
-hb_subset_input_no_subset_tables_set()
-hb_subset_input_drop_tables_set()
-hb_subset_input_set_drop_hints()
-hb_subset_input_get_drop_hints()
-hb_subset_input_set_desubroutinize()
-hb_subset_input_get_desubroutinize()
-hb_subset_input_set_retain_gids()
-hb_subset_input_get_retain_gids()
-hb_subset_input_set_name_legacy()
-hb_subset_input_get_name_legacy()
-hb_subset_input_set_overlaps_flag()
-hb_subset_input_get_overlaps_flag()
-hb_subset_input_set_notdef_outline()
-hb_subset_input_get_notdef_outline()
-hb_subset_input_set_no_prune_unicode_ranges()
-hb_subset_input_get_no_prune_unicode_ranges()
-hb_subset()


Overview of changes leading to 2.9.1
Tuesday, September 7, 2021
====================================
- Final subset API is in place and if no issues are discovered, it will be the
  stable subset API of HarfBuzz 3.0.0. Old API is kept to ease transition, but
  will be removed in 3.0.0.
- Various fuzzer-found bug fixes.
- hb_buffer_append() now handles the pre- and post-context which previously
  were left unchanged in the destination buffer.
- hb-view / hb-shape now accept following new arguments:
  o --unicodes-before/after: takes a list of hex numbers that represent Unicode
    codepoints.
- Undeprecated API:
  hb_set_invert()


Overview of changes leading to 2.9.0
Wednesday, August 18, 2021
History Repeats Itself (Afghanistan)
====================================
- Subsetter API is being stabilized, with the first stable API to happen in
  3.0.0 release (https://github.com/harfbuzz/harfbuzz/issues/3078).
- Support multiple variation axes with same tag, aka HOI.
- The “coretext” testing shaper now passes font variations to CoreText.
- hb-shape/hb-view does not break line at new lines unless text is read from
  file.
- hb-view and hb-subset has a --batch now, similar to hb-shape.
- The --batch mode now uses ; as argument separator instead of : used previously.
- The --batch in hb-shape does not expect 0th argument anymore. That is, the
  lines read are interpreted as argv[1:], instead of argv[0:].
- The --batch option has been undocumented. We are ready to document it; send
  feedback if you find it useful.
- hb-subset got arguments revamps. Added much-requested --gids-file, --glyphs,
  --glyphs-file, --unicodes-file, supporting ranges in --unicodes.
- Various bug fixes.


Overview of changes leading to 2.8.2
Tuesday, July 8, 2021
====================================
- Shaping LTR digits for RTL scripts now makes the native direction of the
  digits LTR, applying shaping and positioning rules on the same glyph order as
  Uniscribe. (Jonathan Kew, Khaled Hosny).
- Subsetting COLR v1 and CPAL tables is now supported. (Garret Rieger, Qunxin Liu)
- Various fixes and improvements to the subsetter. (Garret Rieger, Qunxin Liu, Behdad)
- When applying morx table, mark glyph widths should not be zeroed. (Jonathan Kew)
- GPOS is preferred over kerx, if GSUB was applied. (Behdad)
- Regional_Indicator pairs are grouped together when clustering. (Behdad)
- New API:
+hb_blob_create_or_fail()
+hb_blob_create_from_file_or_fail()
+hb_set_copy()


Overview of changes leading to 2.8.1
Tuesday, May 4, 2021
====================================
- Subsetter now fully supports GSUB/GPOS/GDEF tables (including variations); as
  such, layout tables are retained by subsetter by default. (Garret Rieger, Qunxin Liu)
- Build scripts no longer check for FontConfig as HarfBuzz does not use it.
- hb-view supports iTerm2 and kitty inline image protocols (Khaled Hosny),
  it can also use Chafa for terminal graphics if available (Hans Petter Jansson).

Overview of changes leading to 2.8.0
Tuesday, March 16, 2021
====================================
- Shape joining scripts other than Arabic/Syriac using the Universal Shaping Engine.
  Previously these were shaped using the generalized Arabic shaper. (David Corbett)
- Fix regression in shaping of U+0B55 ORIYA SIGN OVERLINE. (David Corbett)
- Update language tags. (David Corbett)
- Variations: reduce error: do not round each interpolated delta. (Just van Rossum) 
- Documentation improvements. (Khaled Hosny, Nathan Willis)
- Subsetter improvements: subsets most, if not all, lookup types now. (Garret Rieger, Qunxin Liu)
- Fuzzer-found fixes and other improvements when memory failures happen. (Behdad)
- Removed most atomic implementations now that we have C++11 atomic impl. (Behdad)
- General codebase upkeep; using more C++11 features: constexpr constructors, etc. (Behdad)


Overview of changes leading to 2.7.4
Sunday, December 27, 2020
====================================
- Fix missing --enable-introspection configure option from previous release
  tarball.
- Documentation updates.


Overview of changes leading to 2.7.3
Wednesday, December 23, 2020
====================================
- Update USE shaper to 2020-08-13 specification, and other improvements.
- Don’t disable liga feature in myanmar shaper, to match Uniscribe.
- Improvements to language and script tags handling.
- Update language system tag registry to OpenType 1.8.4
- Support for serializing and deserializing Unicode buffers. Serialized buffers
  are now delimited with `<>` or `[]` based on whether it is a Unicode or
  glyphs buffer.
- Increase buffer work limits to handle fonts with many complex lookups.
- Handle more shaping operations in trace output.
- Memory access fixes.
- More OOM fixes.
- Improved documentation.
- Build system improvements.
- New API:
+hb_buffer_has_positions()
+hb_buffer_serialize()
+hb_buffer_serialize_unicode()
+hb_buffer_deserialize_unicode()


Overview of changes leading to 2.7.2
Saturday, August 29, 2020
====================================
- Fix a regression in the previous release that caused a crash with Kaithi.
- More OOM fixes.


Overview of changes leading to 2.7.1
Thursday, August 13, 2020
====================================
- ot-funcs now handles variable empty glyphs better when hvar/vvar isn't present.
- Reverted a GDEF processing regression.
- A couple of fixes to handle OOM better.


Overview of changes leading to 2.7.0
Saturday, July 25, 2020
====================================
- Use an implementation for round that always rounds up, some minor fluctuations
  are expected on var font specially when hb-ot callback is used.
- Fix an AAT's `kerx` issue on broken rendering of Devanagari Sangam MN.
- Remove AAT's `lcar` table support from _get_ligature_carets API, not even much
  use on macOS installed fonts (only two files).  GDEF support is the recommended
  one and expected to work properly after issues fixed two releases ago.
- Minor memory fixes to handle OOM better specially in hb-ft.
- Minor .so files versioning scheme change and remove stable/unstable scheme
  differences, was never used in practice (always default to stable scheme).
- We are now suggesting careful packaging of the library using meson,
  https://github.com/harfbuzz/harfbuzz/wiki/Notes-on-migration-to-meson
  for more information.
- Distribution package URL is changed, either use GitHub generated tarballs,
  `https://github.com/harfbuzz/harfbuzz/archive/$pkgver.tar.gz`
  or, even more preferably use commit hash of the release and git checkouts like,
  `git+https://github.com/harfbuzz/harfbuzz#commit=$commit`


Overview of changes leading to 2.6.8
Monday, June 22, 2020
====================================
- New API to fetch glyph alternates from GSUB table.
- hb-coretext build fix for macOS < 10.10.
- Meson build fixes, cmake port removal is postponed but please prepare for
  it and give us feedback.
  Autotools is still our main build system however please consider
  experimenting with meson also for packaging the library.
- New API:
+hb_ot_layout_lookup_get_glyph_alternates()


Overview of changes leading to 2.6.7
Wednesday, June 3, 2020
====================================
- Update to Unicode 13.0.0.
- Fix hb_ot_layout_get_ligature_carets for fonts without lcar table, it was
  completely broken for all the other fonts since 2.1.2.
- As a part of our migration to meson, this release will be the last one
  to provide cmake port files but autotools still is our main build system.
  There is a possibility that the next version or the after be released
  using meson.


Overview of changes leading to 2.6.6
Tuesday, May 12, 2020
====================================
- A fix in AAT kerning for Geeza Pro.
- Better support for resource fork fonts on macOS.


Overview of changes leading to 2.6.5
Friday, April 17, 2020
====================================
- Add experimental meson build system.  Autotools is still the primary
  and supported build system.
- AAT is now always preferred for horizontal scripts when both AAT and OT
  layout tables exist at the same time.
- Subsetter improvements.
- New API:
+hb_ft_font_lock_face()
+hb_ft_font_unlock_face()


Overview of changes leading to 2.6.4
Monday, October 29, 2019
====================================
- Small bug fix.
- Build fixes.


Overview of changes leading to 2.6.3
Monday, October 28, 2019
====================================
- Misc small fixes, mostly to build-related issues.
- New API:
+hb_font_get_nominal_glyphs()


Overview of changes leading to 2.6.2
Monday, September 30, 2019
====================================
- Misc small fixes, mostly to build-related issues.


Overview of changes leading to 2.6.1
Thursday, August 22, 2019
====================================
- Fix regression with hb_font_create_sub_font scaling introduced in 2.6.0.
- Change interpretation of font PTEM size / CoreText font size handling.
  See https://github.com/harfbuzz/harfbuzz/pull/1484
- hb-ot-font: Prefer symbol cmap subtable if present.
- Apply 'dist'/'abvm'/'blwm' features to all scripts.
- Drop experimental DirectWrite API.


Overview of changes leading to 2.6.0
Tuesday, August 13, 2019
====================================
- New OpenType metrics, baseline, and metadata table access APIs.
- New API to set font variations to a named-instance.
- New hb-gdi.h header and API for creating hb_face_t from HFONT.
- Amalgam: Provide a single-file harfbuzz.cc file for easier alternate building.
- More size-reduction configurable options, enabled by HB_TINY.
- New API:
+hb_font_set_var_named_instance()
+hb_gdi_face_create()
+hb_ot_layout_baseline_tag_t
+hb_ot_layout_get_baseline()
+hb_ot_meta_tag_t
+hb_ot_meta_get_entry_tags()
+hb_ot_meta_reference_entry()
+hb_ot_metrics_tag_t
+hb_ot_metrics_get_position()
+hb_ot_metrics_get_variation()
+hb_ot_metrics_get_x_variation()
+hb_ot_metrics_get_y_variation()


Overview of changes leading to 2.5.3
Wednesday, June 26, 2019
====================================
- Fix UCD script data for Unicode 10+ scripts.  This was broken since 2.5.0.
- More optimizations for HB_TINY.


Overview of changes leading to 2.5.2
Thursday, June 20, 2019
====================================
- More hb-config.hh facilities to shrink library size, namely when built as
  HB_TINY.
- New documentation of custom configurations in CONFIG.md.
- Fix build on gcc 4.8.  That's supported again.
- Universal Shaping Engine improvements thanks to David Corbett.
- API Changes: Undeprecate some horizontal-kerning API and re-enable in hb-ft,
  such that Type1 fonts will continue kerning.


Overview of changes leading to 2.5.1
Friday, May 31, 2019
====================================
- Fix build with various versions of Visual Studio.
- Improved documentation, thanks to Nathan Willis.
- Bugfix in subsetting glyf table.
- Improved scripts for cross-compiling for Windows using mingw.
- Rename HB_MATH_GLYPH_PART_FLAG_EXTENDER to HB_OT_MATH_GLYPH_PART_FLAG_EXTENDER.
  A deprecated macro is added for backwards-compatibility.


Overview of changes leading to 2.5.0
Friday, May 24, 2019
====================================
- This release does not include much functional changes, but includes major internal
  code-base changes.  We now require C++11.  Support for gcc 4.8 and earlier has been
  dropped.
- New hb-config.hh facility for compiling smaller library for embedded and web usecases.
- New Unicode Character Database implementation that is half the size of previously-used
  UCDN.
- Subsetter improvements.
- Improved documentation, thanks to Nathan Willis.
- Misc shaping fixes.


Overview of changes leading to 2.4.0
Monday, March 25, 2019
====================================
- Unicode 12.
- Misc fixes.
- Subsetter improvements.
- New API:
HB_BUFFER_FLAG_DO_NOT_INSERT_DOTTED_CIRCLE
hb_directwrite_face_create()


Overview of changes leading to 2.3.1
Wednesday, January 30, 2019
====================================
- AAT bug fixes.
- Misc internal housekeeping cleanup.


Overview of changes leading to 2.3.0
Thursday, December 20, 2018
====================================
- Fix regression on big-endian architectures.  Ouch!
- Misc bug and build fixes.
- Fix subsetting of simple GSUB/GDEF.
- Merge CFF / CFF2 support contributed by Adobe.  This mostly involves
  the subsetter, but also get_glyph_extents on CFF fonts.

New API in hb-aat.h:
+hb_aat_layout_has_substitution()
+hb_aat_layout_has_positioning()
+hb_aat_layout_has_tracking()


Overview of changes leading to 2.2.0
Thursday, November 29, 2018
====================================
- Misc shaping bug fixes.
- Add font variations named-instance API.
- Deprecate font variations axis enumeration API and add replacement.
- AAT shaping improvements:
  o Fixed 'kern' table Format 2 implementation.
  o Implement 'feat' table API for feature detection.
  o Blacklist 'GSUB' table of fonts from 'MUTF' foundry that also have 'morx'.

New API:
+hb_aat_layout_feature_type_t
+hb_aat_layout_feature_selector_t
+hb_aat_layout_get_feature_types()
+hb_aat_layout_feature_type_get_name_id
+hb_aat_layout_feature_selector_info_t
+HB_AAT_LAYOUT_NO_SELECTOR_INDEX
+hb_aat_layout_feature_type_get_selector_infos()
+hb_ot_var_axis_flags_t
+hb_ot_var_axis_info_t
+hb_ot_var_get_axis_infos()
+hb_ot_var_find_axis_info()
+hb_ot_var_get_named_instance_count()
+hb_ot_var_named_instance_get_subfamily_name_id()
+hb_ot_var_named_instance_get_postscript_name_id()
+hb_ot_var_named_instance_get_design_coords()

Deprecated API:
+HB_OT_VAR_NO_AXIS_INDEX
+hb_ot_var_axis_t
+hb_ot_var_get_axes()
+hb_ot_var_find_axis()


Overview of changes leading to 2.1.3
Friday, November 16, 2018
====================================
- Fix AAT 'mort' shaping, which was broken in 2.1.2


Overview of changes leading to 2.1.2
Friday, November 16, 2018
====================================
- Various internal changes.
- AAT shaping improvements:
  o Implement kern table Format 1 state-machine-based kerning.
  o Implement cross-stream kerning (cursive positioning, etc).
  o Ignore emptyish GSUB tables (zero scripts) if morx present.
  o Don't apply GPOS if morx is being applied.  Matches Apple.


-Overview of changes leading to 2.1.1
Monday, November 5, 2018
====================================
- AAT improvements:
  o Implement 'mort' table.
  o Implement 'kern' subtables Format 1 and Format 3.


Overview of changes leading to 2.1.0
Tuesday, October 30, 2018
====================================
- AAT shaping improvements:
  o Allow user controlling AAT features, for whole buffer only currently.
  o Several 'morx' fixes.
  o Implement tuple-kerns in 'kerx'; Fixes kerning with Apple default
    San Francisco fonts.
- Support for color fonts:
  o COLR/CPAL API to fetch color layers.
  o SVG table to fetch SVG documents.
  o CBDT/sbix API to fetch PNG images.
- New 'name' table API.
- hb-ot-font now uses 'VORG' table to correctly position CFF glyphs
  in vertical layout.
- Various fuzzer-found bug fixes.

Changed API:

A type and a macro added in 2.0.0 were renamed:

hb_name_id_t -> hb_ot_name_id_t
HB_NAME_ID_INVALID -> HB_OT_NAME_ID_INVALID

New API:

+hb_color_t
+HB_COLOR
+hb_color_get_alpha()
+hb_color_get_red()
+hb_color_get_green()
+hb_color_get_blue()
+hb_ot_color_has_palettes()
+hb_ot_color_palette_get_count()
+hb_ot_color_palette_get_name_id()
+hb_ot_color_palette_color_get_name_id()
+hb_ot_color_palette_flags_t
+hb_ot_color_palette_get_flags()
+hb_ot_color_palette_get_colors()
+hb_ot_color_has_layers()
+hb_ot_color_layer_t
+hb_ot_color_glyph_get_layers()
+hb_ot_color_has_svg()
+hb_ot_color_glyph_reference_svg()
+hb_ot_color_has_png()
+hb_ot_color_glyph_reference_png()

+hb_ot_name_id_t
+HB_OT_NAME_ID_INVALID
+HB_OT_NAME_ID_COPYRIGHT
+HB_OT_NAME_ID_FONT_FAMILY
+HB_OT_NAME_ID_FONT_SUBFAMILY
+HB_OT_NAME_ID_UNIQUE_ID
+HB_OT_NAME_ID_FULL_NAME
+HB_OT_NAME_ID_VERSION_STRING
+HB_OT_NAME_ID_POSTSCRIPT_NAME
+HB_OT_NAME_ID_TRADEMARK
+HB_OT_NAME_ID_MANUFACTURER
+HB_OT_NAME_ID_DESIGNER
+HB_OT_NAME_ID_DESCRIPTION
+HB_OT_NAME_ID_VENDOR_URL
+HB_OT_NAME_ID_DESIGNER_URL
+HB_OT_NAME_ID_LICENSE
+HB_OT_NAME_ID_LICENSE_URL
+HB_OT_NAME_ID_TYPOGRAPHIC_FAMILY
+HB_OT_NAME_ID_TYPOGRAPHIC_SUBFAMILY
+HB_OT_NAME_ID_MAC_FULL_NAME
+HB_OT_NAME_ID_SAMPLE_TEXT
+HB_OT_NAME_ID_CID_FINDFONT_NAME
+HB_OT_NAME_ID_WWS_FAMILY
+HB_OT_NAME_ID_WWS_SUBFAMILY
+HB_OT_NAME_ID_LIGHT_BACKGROUND
+HB_OT_NAME_ID_DARK_BACKGROUND
+HB_OT_NAME_ID_VARIATIONS_PS_PREFIX
+hb_ot_name_entry_t
+hb_ot_name_list_names()
+hb_ot_name_get_utf8()
+hb_ot_name_get_utf16()
+hb_ot_name_get_utf32()


Overview of changes leading to 2.0.2
Saturday, October 20, 2018
====================================
- Fix two minor memory access issues in AAT tables.


Overview of changes leading to 2.0.1
Friday, October 19, 2018
====================================
- Fix hb-version.h reported release version that went wrong (1.8.0)
  with previous release.
- Fix extrapolation in 'trak' table.
- Fix hb-font infinite-recursion issue with some font funcs and
  subclassed fonts.
- Implement variation-kerning format in kerx table, although without
  variation.
- Fix return value of hb_map_is_empty().


Overview of changes leading to 2.0.0
Thursday, October 18, 2018
====================================
- Added AAT shaping support (morx/kerx/trak).
  Automatically used if GSUB/GPOS are not available respectively.
  Set HB_OPTIONS=aat env var to have morx/kerx preferred over
  GSUB/GPOS.
- Apply TrueType kern table internally, instead of relying on
  hb_font_t callbacks.
- Khmer shaper significantly rewritten to better match Uniscribe.
- Indic3 tags ('dev3', etc) are passed to USE shaper.
- .dfont Mac font containers implemented.
- Script- and language-mapping revamped to better use BCP 47.
- Misc USE and Indic fixes.
- Misc everything fixes.
- Too many things to list.  Biggest release since 0.9.1, with
  over 500 commits in just over 5 weeks!  Didn't intend it to
  be a big release.  Just happened to become.
- hb-ft now locks underlying FT_Face during use.

API changes:

- Newly-created hb_font_t's now have our internal "hb-ot-font"
  callbacks set on them, so they should work out of the box
  without any callbacks set.  If callbacks are set, everything
  is back to what it was before, the fallback callbacks are
  null.  If you to get the internal implementation modified,
  sub_font it.

- New hb_font_funcs_set_nominal_glyphs_func() allows speeding
  up character to glyph mapping.

New API:
+HB_FEATURE_GLOBAL_START
+HB_FEATURE_GLOBAL_END
+hb_buffer_set_invisible_glyph()
+hb_buffer_get_invisible_glyph()
+hb_font_funcs_set_nominal_glyphs_func()
+hb_ot_layout_table_select_script()
+hb_ot_layout_script_select_language()
+hb_ot_layout_feature_get_name_ids()
+hb_ot_layout_feature_get_characters()
+hb_name_id_t
+HB_NAME_ID_INVALID
+HB_OT_MAX_TAGS_PER_SCRIPT
+hb_ot_tags_from_script_and_language()
+hb_ot_tags_to_script_and_language()

Deprecated API:
-hb_font_funcs_set_glyph_func()
-hb_unicode_eastasian_width_func_t
-hb_unicode_funcs_set_eastasian_width_func()
-hb_unicode_eastasian_width()
-hb_unicode_decompose_compatibility_func_t
-HB_UNICODE_MAX_DECOMPOSITION_LEN
-hb_unicode_funcs_set_decompose_compatibility_func()
-hb_unicode_decompose_compatibility()
-hb_font_funcs_set_glyph_h_kerning_func()
-hb_font_funcs_set_glyph_v_kerning_func()
-hb_font_get_glyph_h_kerning()
-hb_font_get_glyph_v_kerning()
-hb_font_get_glyph_kerning_for_direction()
-hb_ot_layout_table_choose_script()
-hb_ot_layout_script_find_language()
-hb_ot_tags_from_script()
-hb_ot_tag_from_language()


Overview of changes leading to 1.9.0
Monday, September 10, 2018
====================================
- Added 'cmap' API to hb_face_t.
- Face-builder API.
- hb-ot-font re-creation should be much leaner now, as the
  font tables it uses are cached on hb_face_t now.
- Internal source header file name changes:
  hb-*-private.hh is renamed to hb-*.hh.

New API:
+HB_UNICODE_MAX
+hb_face_collect_unicodes()
+hb_face_collect_variation_selectors()
+hb_face_collect_variation_unicodes()
+hb_face_builder_create()
+hb_face_builder_add_table()


Overview of changes leading to 1.8.8
Tuesday, August 14, 2018
====================================
- Fix hb-icu crash on architectures where compare_exchange_weak() can
  fail falsely.  This bug was introduced in 1.8.4.
  https://bugs.chromium.org/p/chromium/issues/detail?id=873568
- More internal refactoring of atomic operations and singletons.
- API changes:
  The following functions do NOT reference their return value before
  returning:
  * hb_unicode_funcs_get_default()
  * hb_glib_get_unicode_funcs()
  * hb_icu_get_unicode_funcs()
  This is consistent with their naming ("get", instead of "reference")
  as well as how they are used in the wild (ie. no one calls destroy()
  on their return value.)


Overview of changes leading to 1.8.7
Wednesday, August 8, 2018
====================================
- Fix assertion failure with GDEF-blacklisted fonts.


Overview of changes leading to 1.8.6
Tuesday, August 7, 2018
====================================
- Internal code shuffling.
- New API to speed up getting advance widths for implementations
  that have heavy overhead in get_h_advance callback:
+hb_font_funcs_set_glyph_h_advances_func
+hb_font_funcs_set_glyph_v_advances_func
+hb_font_get_glyph_advances_for_direction
+hb_font_get_glyph_h_advances
+hb_font_get_glyph_h_advances_func_t
+hb_font_get_glyph_v_advances
+hb_font_get_glyph_v_advances_func_t


Overview of changes leading to 1.8.5
Wednesday, August 1, 2018
====================================
- Major Khmer shaper improvements to better match Microsoft.
- Indic bug fixes.
- Internal improvements to atomic operations.


Overview of changes leading to 1.8.4
Tuesday, July 17, 2018
====================================
- Fix build on non-C++11.
- Use C++-style GCC atomics and C++11 atomics.


Overview of changes leading to 1.8.3
Wednesday, July 11, 2018
====================================
- A couple of Indic / USE bug fixes.
- Disable vectorization, as it was causing unaligned access bus error on
  certain 32bit architectures.


Overview of changes leading to 1.8.2
Tuesday, July 3, 2018
====================================
- Fix infinite loop in Khmer shaper.
- Improve hb_blob_create_from_file() for streams.


Overview of changes leading to 1.8.1
Tuesday, June 12, 2018
====================================
- Fix hb-version.h file generation; last two releases went out with wrong ones.
- Add correctness bug in hb_set_t operations, introduced in 1.7.7.
- Remove HB_SUBSET_BUILTIN build option.  Not necessary.


Overview of changes leading to 1.8.0
Tuesday, June 5, 2018
====================================
- Update to Unicode 11.0.0.


Overview of changes leading to 1.7.7
Tuesday, June 5, 2018
====================================
- Lots of internal changes, but not yet exposed externally.
- All HarfBuzz objects are significantly smaller in size now.
- Sinhala: Position repha on top of post-consonant, not base.
  This better matches Windows 10 behavior, which was changed
  from previous Windows versions.
- New build options:
  o New cpp macro HB_NO_ATEXIT
  o New cpp macro HB_SUBSET_BUILTIN
- Significant libharfbuzz-subset changes. API subject to change.
- New API in libharfbuzz:

+hb_blob_create_from_file()
+hb_face_count()

A hashmap implementation:
+hb-map.h
+HB_MAP_VALUE_INVALID
+hb_map_t
+hb_map_create()
+hb_map_get_empty()
+hb_map_reference()
+hb_map_destroy()
+hb_map_set_user_data()
+hb_map_get_user_data()
+hb_map_allocation_successful()
+hb_map_clear()
+hb_map_is_empty()
+hb_map_get_population()
+hb_map_set()
+hb_map_get()
+hb_map_del()
+hb_map_has()


Overview of changes leading to 1.7.6
Wednesday, March 7, 2018
====================================

- Fix to hb_set_t binary operations. Ouch.
- New experimental harfbuzz-subset library. All of hb-subset.h
  is experimental right now and API WILL change.

- New API:
hb_blob_copy_writable_or_fail()
HB_OT_TAG_BASE
hb_set_previous()
hb_set_previous_range()


Overview of changes leading to 1.7.5
Tuesday, January 30, 2018
====================================

- Separate Khmer shaper from Indic.
- First stab at AAT morx. Not hooked up.
- Misc bug fixes.


Overview of changes leading to 1.7.4
Wednesday, December 20, 2017
====================================

- Fix collect_glyphs() regression caused by hb_set_t changes.


Overview of changes leading to 1.7.3
Monday, December 18, 2017
====================================

- hb_set_t performance tuning and optimizations.
- Speed up collect_glyphs() and reject garbage data.
- In hb_coretext_font_create() set font point-size (ptem).
- Misc fixes.


Overview of changes leading to 1.7.2
Monday, December 4, 2017
====================================

- Optimize hb_set_add_range().
- Misc fixes.
- New API:
hb_coretext_font_create()


Overview of changes leading to 1.7.1
Tuesday, November 14, 2017
====================================

- Fix atexit object destruction regression.
- Fix minor integer-overflow.


Overview of changes leading to 1.7.0
Monday, November 13, 2017
====================================

- Minor Indic fixes.
- Implement kerning and glyph names in hb-ot-font.
- Various DSO optimization re .data and .bss sizes.
- Make C++11 optional; build fixes.
- Mark all other backends "unsafe-to-break".
- Graphite fix.


Overview of changes leading to 1.6.3
Thursday, October 26th, 2017
====================================

- Fix hb_set_t some more.  Should be solid now.
- Implement get_glyph_name() for hb-ot-font.
- Misc fixes.


Overview of changes leading to 1.6.2
Monday, October 23nd, 2017
====================================

- Yesterday's release had a bad crasher; don't use it.  That's what
  happens when one works on Sunday...
  https://github.com/harfbuzz/harfbuzz/issues/578
- Build fixes for FreeBSD and Chrome Android.


Overview of changes leading to 1.6.1
Sunday, October 22nd, 2017
====================================

- Don't skip over COMBINING GRAPHEME JOINER when ligating, etc.
  To be refined: https://github.com/harfbuzz/harfbuzz/issues/554
- Faster hb_set_t implementation.
- Don't use deprecated ICU API.
- Fix undefined-behavior in Myanmar shaper, introduced in 1.6.0
- Deprecated API:
  hb_set_invert()


Overview of changes leading to 1.6.0
Friday, October the 13th, 2017
====================================

- Update to Unicode 10.

- Various Indic and Universal Shaping Engine fixes as a result of
  HarfBuzz Hackfest with Jonathan Kew at Web Engines Hackfest at
  the Igalia offices in A Coruña, Spain.  Thanks Igalia for having
  us!

- Implement Unicode Arabic Mark Ordering Algorithm UTR#53.

- Implement optical sizing / tracking in CoreText backend, using
  new API hb_font_set_ptem().

- Allow notifying hb_font_t that underlying FT_Face changed sizing,
  using new API hb_ft_font_changed().

- More Graphite backend RTL fixes.

- Fix caching of variable font shaping plans.

- hb-view / hb-shape now accept following new arguments:

  o --unicodes: takes a list of hex numbers that represent Unicode
    codepoints.

New API:
+hb_face_get_table_tags()
+hb_font_set_ptem()
+hb_font_get_ptem()
+hb_ft_font_changed()


Overview of changes leading to 1.5.1
Tuesday, September 5, 2017
====================================

- Fix "unsafe-to-break" in fallback shaping and other corner cases.
  All our tests pass with --verify now, meaning unsafe-to-break API
  works as expected.
- Add --unicodes to hb-view / hb-shape.
- [indic] Treat Consonant_With_Stacker as consonant.  This will need
  further tweaking.
- hb_buffer_diff() tweaks.


Overview of changes leading to 1.5.0
Wednesday, August 23, 2017
====================================

- Misc new API, for appending a buffer to another, and for comparing
  contents of two buffers for types of differences.

- New "unsafe-to-break" API.  Can be used to speed up reshaping
  in line-breaking situations.  Essentially, after shaping, it returns
  positions in the input string (some of the cluster boundaries) that
  are "safe to break" in that if the text is segmented at that position
  and two sides reshaped and concatenated, the shaping result is
  exactly the same as shaping the text in one piece.

  hb-view and hb-shape and hb-shape now take --verify, which verifies
  the above property.

  Some corner cases of the implementation are still not quite working.
  Those will be fixed in subsequent releases.
