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Release Name: 2.3.0
Notes:
CHANGES BETWEEN 2.3.0 and 2.2.1
I. IMPORTANT BUG FIXES
- The PCF font loader is now much more robust while loading
malformed font files.
- Various memory leaks have been found and fixed.
- The TrueType name loader now deals properly with some fonts that
encode their names in UTF-16 (the specification was vague, and
the code incorrectly assumed UCS-4).
- Fixed the TrueType bytecode loader to deal properly with subtle
monochrome/gray issues when scaling the CVT. Some fonts
exhibited bad rendering artifacts otherwise.
- `FT_GlyphSlot_Embolden' now supports vertical layouts correctly
(it mangled the vertical advance height).
- Fixed byte endian issues of `ftmac.c' to support Mac OS X on
i386.
- The PFR font loader no longer erroneously tags font files
without any outlines as FT_FACE_FLAG_SCALABLE.
II. NEW API FUNCTIONS
- `FT_Library_SetLcdFilter' allows you to select a special filter
to be applied to the bitmaps generated by `FT_Render_Glyph' if
one of the FT_RENDER_MODE_LCD and FT_RENDER_MODE_LCD_V modes has
been selected. This filter is used to reduce color fringes;
several settings are available through the FT_LCD_FILTER_XXX
enumeration.
Its declaration and documentation can be found in file
`include/freetype/ftlcdfil.h' (to be accessed with macro
FT_LCD_FILTER_H).
*IMPORTANT*: This function returns an error
(FT_Err_Unimplemented_Feature) in default builds of the library
for patent reasons. See below.
- `FT_Get_Gasp' allows you to query the flags of the TrueType
`gasp' table for a given character pixel size. This is useful
to duplicate the text rendering of MS Windows when the native
bytecode interpreter is enabled (which isn't the default for
other patent reasons).
Its declaration and documentation can be found in file
`include/freetype/ftgasp.h' (to be accessed with macro
FT_GASP_H).
III. IMPORTANT CHANGES
- The auto-hinter has been tuned a lot to improve its results with
serif fonts, resulting in much better font rendering of many web
pages.
- The unpatented hinter is now part of the default build of the
library; we have added code to automatically support `tricky'
fonts that need it.
This means that FreeType should `just work' with certain Asian
fonts, like MingLiU, which cannot properly be loaded without a
bytecode interpreter, but which fortunately do not use any of
the patented bytecode opcodes. We detect these fonts by name,
so please report any font file that doesn't seem to work with
FreeType, and we shall do what we can to support it in a next
release.
Note that the API hasn't changed, so you can still force
unpatented hinting with a special parameter to `FT_Open_Face' as
well. This might be useful in same cases; for example, a PDF
reader might present a user option to activate it to deal with
certain `tricky' embedded fonts which cannot be clearly
identified.
If you are a developer for embedded systems, you might want to
*disable* the feature to save code space by undefining
TT_CONFIG_OPTION_UNPATENTED_HINTING in file `ftoption.h'.
- LCD-optimized rendering is now *disabled* in all default builds
of the library, mainly due to patent issues. For more
information see:
http://lists.gnu.org/archive/html/freetype/2006-09/msg00064.html
A new configuration macro FT_CONFIG_OPTION_SUBPIXEL_RENDERING
has been introduced in `ftoption.h'; manually define it in this
file if you want to re-enable the feature.
The change only affects the implementation, not the FreeType
API. This means that clients don't need to be modified, because
the library still generates LCD decimated bitmaps, but with the
added constraint that R=G=B on each triplet.
The displayed result should be equal to normal anti-aliased
rendering.
Additionally, if FT_CONFIG_OPTION_SUBPIXEL_RENDERING is not
defined, the new `FT_Library_SetLcdFilter' function returns the
FT_Err_Unimplemented_Feature error code.
- Some computation bugs in the TrueType bytecode interpreter were
found, which allow us to get rid of very subtle and rare
differences we had experienced with the Windows renderer.
- It is now possible to cross-compile the library easily. See the
file `docs/INSTALL.CROSS' for details.
- The file `src/base/ftmac.c' now contains code for Mac OS X only;
its deprecated function `FT_GetFile_From_Mac_Font_Name' always
returns an error even if the QuickDraw framework is available.
The previous version has been moved to `builds/mac/ftmac.c'.
Selecting configure option `--with-quickdraw-carbon' makes the
build process use the original `ftmac.c' file instead of the Mac
OS X-only version.
IV. MISCELLANEOUS
- Various performance and memory footprint optimizations have been
performed on the TrueType and CFF font loaders, sometimes with
very drastic benefits (e.g., the TrueType loader is now about
25% faster; FreeType should use less heap memory under nearly
all conditions).
- The anti-aliased rasterizer has been optimized and is now 15% to
25% percent faster than in previous versions, depending on
content.
- The Type 1 loader has been improved; as an example, it now skips
top-level dictionaries properly.
- Better support for Mac fonts on POSIX systems, plus compilation
fixes for Mac OS X on ppc64 where `ftmac.c' cannot be built.
- Configuration without `--with-old-mac-fonts' does not include
`ftmac.c' (this was the behaviour in FreeType version 2.1.10).
- The TrueTypeGX validator (gxvalid) checks the order of glyph IDs
in the kern table. |
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