ref: f78ca0dbb956fbd736698886522a344acfd50a91
dir: /docs/CHANGES/
CHANGES BETWEEN 2.5.3 and 2.5.4
I. IMPORTANT BUG FIXES
- The new auto-hinter code using HarfBuzz crashed for some invalid
fonts.
II. IMPORTANT CHANGES
- Full auto-hinter support of the Devanagari script.
III. MISCELLANEOUS
- Improvements to the auto-hinter's algorithm to recognize stems
and local extrema.
- Function `FT_Get_SubGlyph_Info' always returned an error even in
case of success.
- Version 2.5.1 introduced major bugs in the cjk part of the
auto-hinter, which are now fixed.
- `cmake' now supports a build of FreeType as an OS X framework.
======================================================================
CHANGES BETWEEN 2.5.2 and 2.5.3
I. IMPORTANT BUG FIXES
- A vulnerability (CVE-2014-2240) was identified and fixed in the
new CFF driver (cf. http://savannah.nongnu.org/bugs/?41697).
All users should upgrade.
- More bug fixes related to correct positioning of composite
glyphs.
- Many fixes to better protect against malformed input.
II. IMPORTANT CHANGES
- FreeType can now use the HarfBuzz library to greatly improve the
auto-hinting of fonts that use OpenType features: Many glyphs
that are part of such features but don't have cmap entries are
now handled properly, for example small caps or superscripts.
Define the configuration macro FT_CONFIG_OPTION_USE_HARFBUZZ to
activate HarfBuzz support.
You need HarfBuzz version 0.9.19 or newer.
Note that HarfBuzz depends on FreeType; this currently causes a
chicken-and-egg problem that can be solved as follows in case
HarfBuzz is not yet installed on your system.
1. Compile and install FreeType without the configuration
macro FT_CONFIG_OPTION_USE_HARFBUZZ.
2. Compile and install HarfBuzz.
3. Define macro FT_CONFIG_OPTION_USE_HARFBUZZ, then compile
and install FreeType again.
With FreeType's `configure' script the procedure boils down to
configure, build, and install Freetype, then configure, compile,
and install HarfBuzz, then configure, compile, and install
FreeType again (after executing `make distclean').
- All libraries FreeType depends on are now checked using the
`pkg-config' configuration files first, followed by alternative
methods.
- The new value `auto' for the various `--with-XXX' library
options (for example `--with-harfbuzz=auto') makes the
`configure' script automatically link to the libraries it finds.
This is now the default.
- In case FreeType's `configure' script can't find a library, you
can pass environment variables to circumvent pkg-config, and
those variables have been harmonized as a consequence of the
changes mentioned above:
LIBZ -> removed; use LIBZ_CFLAGS and LIBZ_LIBS
LIBBZ2 -> removed; use BZIP2_CFLAGS and BZIP2_LIBS
LIBPNG_LDFLAGS -> LIBPNG_LIBS
`./configure --help' shows all available environment variables.
- The `freetype-config' script now understands option `--static'
to emit static linking information.
======================================================================
CHANGES BETWEEN 2.5.1 and 2.5.2
I. IMPORTANT BUG FIXES
- Improving the display of some broken TrueType fonts introduced a
bug that made FreeType crash on some popular (but not fully
conformant) fonts like `ahronbd.ttf'.
- Another round of improvements to correct positioning and hinting
of composite glyphs in TrueType fonts.
II. MISCELLANEOUS
- Version 2.5.1 introduced a bug in handling embedded bitmap
strikes of TrueType fonts, causing garbage display under some
circumstances.
- The `ftgrid' demo program couldn't be compiled in
non-development builds.
======================================================================
CHANGES BETWEEN 2.5 and 2.5.1
I. IMPORTANT BUG FIXES
- For some WinFNT files, the last glyph wasn't displayed but
incorrectly marked as invalid.
- The vertical size of glyphs was incorrectly set after a call to
`FT_GlyphSlot_Embolden', resulting in clipped glyphs.
- Many fields of the `PCLT' table in SFNT based fonts (if accessed
with `FT_Get_Sfnt_Table') were computed incorrectly.
- In TrueType fonts, hinting of composite glyphs could sometimes
deliver incorrect positions of components or even distorted
shapes.
II. IMPORTANT CHANGES
- WOFF font format support has been added.
- The auto-hinter now supports Hebrew. Greek and Cyrillic support
has been improved.
- Support for the forthcoming `OS/2' SFNT table version 5, as can
be found e.g. in the `Sitka' font family for Windows 8.1.
- The header file layout has been changed. After installation,
all files are now located in `<prefix>/include/freetype2'.
Applications that use (a) `freetype-config' or FreeType's
`pkg-config' file to get the include directory for the compiler,
and (b) the documented way for header inclusion like
#include <ft2build.h>
#include FT_FREETYPE_H
...
don't need any change to the source code.
III. MISCELLANEOUS
- The stem darkening feature of the new CFF engine can now be
fine-tuned with the new `darkening-parameters' property.
- `ftgrid' has been updated to toggle various engines with the `H'
key, similar to `ftview' and `ftdiff'.
- The functionality of `ttdebug' has been greatly enhanced.
. It now displays twilight, storage, and control value data; key
`T' shows the twilight point table, key `S' the storage data,
and key `C' the control value table.
. Some keys have been reassigned from lowercase to their
uppercase equivalents; for example `q' to quit the program is
now `Q'.
. Key `f' finishes the current function.
. Key `R' restarts the debugger.
. Keys `b' and `p' set a breakpoint.
. Key `B' provides a function call backtrace.
- Better support of ARMv7 and x86_64 processors.
- Apple's `sbix' color bitmap format is now supported.
- Improved auto-hinter rendering for many TrueType fonts,
especially in the range 20-40ppem.
- A new face flag `FT_FACE_FLAG_COLOR' has been added (to be
accessed with the macro `FT_HAS_COLOR').
- `FT_Gzip_Uncompress' (modeled after zlib's `uncompress'
function) has been added; this is a by-product of the newly
added WOFF support.
- Support for a build with `cmake' has been contributed by John
Cary <[email protected]>.
- Support for x64 builds with Visual C++ has been contributed by
Kenneth Miller <[email protected]>
- Manual pages for most demo programs have been added.
- The GETINFO bytecode instruction for TrueType fonts was buggy if
used to retrieve subpixel hinting information. It was necessary
to set selector bit 6 to get results for selector bits 7-10,
which is wrong.
- Improved computation of emulated vertical metrics for TrueType
fonts.
- Fixed horizontal start-up position of vertical phantom points in
TrueType bytecode.
======================================================================
CHANGES BETWEEN 2.4.12 and 2.5
I. IMPORTANT BUG FIXES
- The cache manager function `FTC_Manager_Reset' didn't flush the
cache.
II. IMPORTANT CHANGES
- Behdad Esfahbod (on behalf of Google) contributed support for
color embedded bitmaps (eg. color emoji).
A new load flag, FT_LOAD_COLOR, makes FreeType load color
embedded-bitmaps, following this draft specification
https://color-emoji.googlecode.com/git/specification/v1.html
which defines two new SFNT tables, `CBDT' and `CBLC' (named and
modeled after `EBDT' and `EBLC', respectively). The color
bitmaps are stored in the new FT_PIXEL_MODE_BGRA format to
represent BGRA pre-multiplied sRGB images. If PNG support is
available, PNG color images as defined in the same proposed
specification are supported also.
Note that color bitmaps are converted to grayscale if client
didn't ask for color.
- As announced in the previous release, the old FreeType CFF
engine is now disabled by default. It can be conditionally
compiled by defining the configuration macro
CFF_CONFIG_OPTION_OLD_ENGINE.
- As announced in the previous release, all code related to macro
FT_CONFIG_OPTION_OLD_INTERNALS has been removed, thus becoming
obsolete.
III. MISCELLANEOUS
- The property API (`FT_Property_Get' and `FT_Property_Set') is
now declared as stable.
The exception, however, are the experimental auto-hinter
properties `glyph-to-script-map' and `fallback-script' which are
subject to change in a forthcoming release.
- `ftview' has been updated to support color embedded bitmaps; it
can be toggled on and off with key `c'. The small cache toggle
is now key `K'.
- It is now possible to control the version of the TrueType
hinting engine using the new `interpreter-version' property of
the `truetype' module: Versions 35 and 38 (the default) are
supported, which roughly corresponds to disable and enable
subpixel hinting support, respectively.
In both `ftview' and `ftdiff', switching between the two
versions can be done with key `H'. In the `ftbench' demo
program, command line option `-H' has been extended to activate
the non-default interpreter version.
- The `ttdebug' program has been further improved. In particular,
it accepts a new command line option `-H' to select the hinting
engine.
- `ftdump's verbose option has been renamed to `-V'. For all demo
programs, `-v' now shows version information.
- Another round of TrueType subpixel hinting fixes.
- The `apinames' tool can now create an import file for NetWare.
- 64bit compilation of the new CFF engine was buggy.
- Some fixes to improve robustness in memory-tight situations.
======================================================================
CHANGES BETWEEN 2.4.11 and 2.4.12
- We have another CFF parsing and hinting engine! Written by Dave
Arnold <[email protected]>, this work has been contributed by
Adobe in collaboration with Google. It is vastly superior to
the old CFF engine, and it will replace it in the next release.
Right now, it is still off by default, and you have to
explicitly select it using the new `hinting-engine' property of
the cff driver:
...
#include FT_MODULE_H
#include FT_CFF_DRIVER_H
FT_Library library;
int engine = FT_CFF_HINTING_ADOBE;
...
FT_Property_Set( library, "cff", "hinting-engine", &engine );
The code has a (mature) beta status; we encourage all users to
test it and report any problems.
In case you want to activate the new CFF engine unconditionally,
apply this patch:
--- snip ---
diff --git a/src/cff/cffobjs.c b/src/cff/cffobjs.c
index ebcf189..3f2ce6b 100644
--- a/src/cff/cffobjs.c
+++ b/src/cff/cffobjs.c
@@ -1056,7 +1056,7 @@
/* set default property values */
- driver->hinting_engine = FT_CFF_HINTING_FREETYPE;
+ driver->hinting_engine = FT_CFF_HINTING_ADOBE;
driver->no_stem_darkening = FALSE;
return FT_Err_Ok;
--- snip ---
- The macro FT_CONFIG_OPTION_OLD_INTERNALS is no longer set by
default. In the next release, we will completely remove the
associated code. Please update your programs in case you are
still using this macro.
II. MISCELLANEOUS
- The (top-level) `configure' script now respects the MAKE
environment variable to specify a `make' binary. For backwards
compatibility, GNUMAKE still overrides MAKE, though.
- The `ftview' and `ftdiff' demo programs have been redesigned,
showing more options permanently on the screen, among other
minor improvements.
- Using the `H' key, it is now possible to select the CFF engine
in both `ftview' and `ftdiff'.
- The new command line option `-H' for `ftbench' selects the Adobe
CFF engine.
- It is now possible to directly select the LCD rendering mode
with the keys `A'-`F' in `ftview'. The key mapping for cycling
through LCD modes has been changed from `K' and `L' to `k' and
`l', and toggling custom LCD filtering is no longer mapped to
key `F' but to key `L'.
- In `ftdiff', key `x' toggles between layout modes: Either use
the advance width (this is new and now the default) or the
bounding box information to determine line breaks.
- For all demo tools, the new command line option `-v' shows the
version.
- For the demo tools with a GUI, the new command line options `-w'
and `-h' select the width and the height of the output window,
respectively.
- The `ttdebug' program was broken and has been reactivated. Note
that this program is not compiled by default.
======================================================================
CHANGES BETWEEN 2.4.10 and 2.4.11
I. IMPORTANT BUG FIXES
- Some vulnerabilities in the BDF implementation have been fixed.
Users of this font format should upgrade.
II. IMPORTANT CHANGES
- Subpixel hinting support has been contributed by Infinality,
based on Greg Hitchcock's whitepaper at
http://www.microsoft.com/typography/cleartype/truetypecleartype.aspx
Originally, it was a separate patch available from
http://www.infinality.net/blog/
and which has been integrated.
Note that ClearType support is not completely implemented! In
particular, full support for the options `compatible_widths',
`symmetrical_smoothing, and `bgr' (via the GETINFO bytecode
instruction) is missing.
Activation of subpixel hinting support can be controlled with
the `TT_CONFIG_OPTION_SUBPIXEL_HINTING' configuration option; it
is switched off by default. This feature is still experimental;
we welcome test reports!
- Support for OpenType collections (OTC) has been added.
- Pure CFF fonts within an SFNT wrapper are now supported.
III. MISCELLANEOUS
- Minor rendering improvements to the auto-hinter.
- `FT_GlyphSlot_Oblique' now uses a shear angle of 12°.
- Experimental support to handle `property modules', for example
to control the behaviour of the auto-hinter. The API consists
of two new functions, `FT_Property_Set' and `FT_Property_Get'.
The code is still subject to change and should not be used for
production.
- The `ftdiff' demo program now supports UTF-8 encoded input files
for option `-f'.
- Using keys `r' and `R', you can now adjust the stroker radius in
the `ftview' demo program.
- Other, minor fixes and improvements.
======================================================================
CHANGES BETWEEN 2.4.9 and 2.4.10
I. IMPORTANT BUG FIXES
- Incremental glyph loading as needed by ghostscript was broken.
II. MISCELLANEOUS
- A new function `FT_Outline_EmboldenXY', contributed by Alexei
Podtelezhnikov.
- In the `ftview' demo program, key `e' has been replaced with `x'
and `y' to embolden in the horizontal and vertical direction,
respectively.
- The glyph spacing computation in `FT_GlyphSlot_Embolden' (and
similar code in `ftview') has been improved.
- Minor improvements to the TrueType bytecode interpreter and
glyph loader, the auto-hinter, and the B/W rasterizer.
======================================================================
CHANGES BETWEEN 2.4.8 and 2.4.9
I. IMPORTANT BUG FIXES
- Another round of fixes to better handle invalid fonts. Many of
them are vulnerabilities (see CVE-2012-1126 up to CVE-2012-1144
and SA48320) so all users should upgrade.
II. MISCELLANEOUS
- The `ENCODING -1 <n>' format of BDF fonts is now supported.
- For BDF fonts, support for the whole Unicode encoding range has
been added.
- Better TTF support for x_ppem != y_ppem.
- `FT_Get_Advances' sometimes returned bogus values.
- The demo programs no longer recognize and handle default
suffixes; you now have to always specify the complete font name.
- Better rendering and LCD mode cycling added to `ftview'.
======================================================================
CHANGES BETWEEN 2.4.7 and 2.4.8
I. IMPORTANT BUG FIXES
- Some vulnerabilities in handling CID-keyed PostScript fonts have
been fixed; see CVE-2011-3439.
II. MISCELLANEOUS
- Chris Liddell contributed a new API, `FT_Get_PS_Font_Value', to
retrieve most of the dictionary keys in Type 1 fonts.
======================================================================
CHANGES BETWEEN 2.4.6 and 2.4.7
I. IMPORTANT BUG FIXES
- Some vulnerabilities in handling Type 1 fonts have been fixed;
see CVE-2011-3256.
II. MISCELLANEOUS
- FreeType now properly handles ZapfDingbats glyph names while
constructing a Unicode character map (for fonts which don't have
one).
======================================================================
CHANGES BETWEEN 2.4.5 and 2.4.6
I. IMPORTANT BUG FIXES
- For TrueType based fonts, the ascender and descender values were
incorrect sometimes (off by a pixel if the ppem value was not a
multiple of 5). Depending on the use you might now experience
a different layout; the change should result in better, more
consistent line spacing.
- Fix CVE-2011-0226 which causes a vulnerability while handling
Type 1 fonts.
- BDF fonts containing glyphs with negative values for ENCODING
were incorrectly rejected. This bug has been introduced in
FreeType version 2.2.0.
- David Bevan contributed a major revision of the FreeType stroker
code:
. The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected.
. A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has
been introduced to support PostScript and PDF miter joins.
. FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an
alias for FT_STROKER_LINEJOIN_MITER.
. Various stroking glitches has been fixed.
II. MISCELLANEOUS
- SFNT bitmap fonts which contain an outline glyph for `.notdef'
only no longer set the FT_FACE_FLAG_SCALABLE flag.
======================================================================
CHANGES BETWEEN 2.4.4 and 2.4.5
I. IMPORTANT BUG FIXES
- A rendering regression for second-order Bézier curves has been
fixed, introduced in 2.4.3.
II. IMPORTANT CHANGES
- If autohinting is not explicitly disabled, FreeType now uses
the autohinter if a TrueType based font doesn't contain native
hints.
- The load flag FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH has been made
redundant and is simply ignored; this means that FreeType now
ignores the global advance width value in TrueType fonts.
III. MISCELLANEOUS
- `FT_Sfnt_Table_Info' can now return the number of SFNT tables of
a font.
- Support for PCF files compressed with bzip2 has been contributed
by Joel Klinghed. To make this work, the OS must provide a
bzip2 library.
- Bradley Grainger contributed project and solution files in
Visual Studio 2010 format.
- Again some fixes to better handle broken fonts.
- Some improvements to the B/W rasterizer.
- Fixes to the cache module to improve robustness.
- Just Fill Bugs contributed (experimental) code to compute blue
zones for CJK Ideographs, improving the alignment of horizontal
stems at the top or bottom edges.
- The `ftgrid' demo program can now display autohinter segments,
to be toggled on and off with key `s'.
======================================================================
CHANGES BETWEEN 2.4.3 and 2.4.4
I. IMPORTANT BUG FIXES
- UVS support (TrueType/OpenType cmap format 14) support is fixed.
This regression has been introduced in version 2.4.0.
II. MISCELLANEOUS
- Detect tricky fonts (e.g. MingLiU) by the lengths and checksums
of Type42-persistent subtables (`cvt ', `fpgm', and `prep') when
a TrueType font without family name is given. The previous fix,
introduced in 2.4.3, was too rigorous, causing many subsetted
fonts (mainly from PDF files) displayed badly because FreeType
forced rendering with the TrueType bytecode engine instead of
the autohinter.
- Better support for 64bit platforms.
- More fixes to improve handling of broken fonts.
======================================================================
CHANGES BETWEEN 2.4.2 and 2.4.3
I. IMPORTANT BUG FIXES
- Fix rendering of certain cubic, S-shaped arcs. This regression
has been introduced in version 2.4.0.
II. MISCELLANEOUS
- To fix the above mentioned rendering issue, a new spline
flattening algorithm has been introduced which speeds up both
conic and cubic arcs.
- Handling of broken fonts has been further improved.
======================================================================
CHANGES BETWEEN 2.4.1 and 2.4.2
I. IMPORTANT BUG FIXES
- A stack overflow in CFF Type2 CharStrings interpreter is fixed.
- Handling Type 42 font deallocation was broken; additionally, the
library is now more robust against malformed Type 42 fonts.
II. MISCELLANEOUS
- Two new functions, `FT_Reference_Library' (in FT_MODULE_H) and
`FT_Reference_Face' (in FT_FREETYPE_H), have been added to
simplify life-cycle management. A counter gets initialized to 1
at the time an FT_Library (or FT_Face) structure is created.
The two new functions increment the respective counter.
`FT_Done_Library' and `FT_Done_Face' then only destroy a library
or face if the counter is 1, otherwise they simply decrement the
counter.
======================================================================
CHANGES BETWEEN 2.4.0 and 2.4.1
I. IMPORTANT CHANGES
- A serious bug in the CFF font module prevented display of many
glyphs in CFF fonts like `MinionPro-Regular.otf'.
======================================================================
CHANGES BETWEEN 2.3.12 and 2.4.0
I. IMPORTANT CHANGES
- Since May 2010, all patents regarding the TrueType bytecode
interpreter have expired worldwide. Consequently, we now define
TT_CONFIG_OPTION_BYTECODE_INTERPRETER by default (and undefine
TT_CONFIG_OPTION_UNPATENTED_HINTING).
- A new function `FT_Library_SetLcdFilterWeights' is available to
adjust the filter weights set by `FT_Library_SetLcdFilter'.
II. MISCELLANEOUS
- Thanks to many reports from Robert Święcki, FreeType's stability
in handling broken or damaged fonts is much improved.
- Support for LCD filter control has been added to the demo
programs `ftdiff' and `ftview'.
======================================================================
CHANGES BETWEEN 2.3.11 and 2.3.12
I. IMPORTANT CHANGES
- For `FT_Open_Face', new parameters are available to ignore
preferred family names: FT_PARAM_TAG_IGNORE_PREFERRED_FAMILY and
FT_PARAM_TAG_IGNORE_PREFERRED_SUBFAMILY.
II. MISCELLANEOUS
- Support for incremental font loading (controlled with the
FT_CONFIG_OPTION_INCREMENTAL macro) is now active by default.
- Better support for vertical metrics.
- Various minor bug fixes.
======================================================================
CHANGES BETWEEN 2.3.10 and 2.3.11
I. IMPORTANT BUG FIXES
- Version 2.3.10 broke PCF support.
======================================================================
CHANGES BETWEEN 2.3.10 and 2.3.9
I. IMPORTANT BUG FIXES
- If all ASCII digits in a font have the same (unscaled) width,
the autohinter respects this and won't change it.
- TrueType fonts are now rasterized correctly if the horizontal
and vertical resolution differ.
- Type 1 fonts are now handled with increased precision internally
to avoid serious rounding issues if non-integral coordinates are
encountered.
- Horizontally condensed CFF fonts (using the font matrix) were
rendered incorrectly. This bug has been introduced after
release 2.3.5.
II. IMPORTANT CHANGES
- Support for the SFNT cmap 13 table format (as defined by the new
OpenType 1.6 specification) has been added.
- B/W rasterization of well-hinted TrueType fonts at small sizes
has been greatly improved.
- Calculation of vertical metrics in OpenType fonts has been
improved.
III. MISCELLANEOUS
- It is now possible to change the emboldening factor in the
`ftview' demo program with keys `e' and `E'.
- It is now possible to change the slant value in the `ftview'
demo program with keys `s' and `S'.
- The 5-levels grayscale mode of the `ftraster' module (which
FreeType doesn't use by default) was broken since version 2.3.0.
- Compilation of the `ftgrays' and `ftraster' modules was broken
in stand-alone mode.
- Various fixes for compilation on 64bit and 16bit architectures.
======================================================================
CHANGES BETWEEN 2.3.9 and 2.3.8
I. IMPORTANT BUG FIXES
- Very unfortunately, FreeType 2.3.8 contained a change that broke
its official ABI. The end result is that programs compiled
against previous versions of the library, but dynamically linked
to 2.3.8 can experience memory corruption if they call the
`FT_Get_PS_Font_Info' function.
We recommend all users to upgrade to 2.3.9 as soon as possible,
or to downgrade to a previous release of the library if this is
not an option.
The origin of the bug is that a new field was added to the
publicly defined `PS_FontInfoRec' structure. Unfortunately,
objects of this type can be stack or heap allocated by callers
of `FT_Get_PS_Font_Info', resulting in a memory buffer
overwrite with its implementation in 2.3.8.
If you want to know whether your code is vulnerable to this
issue, simply search for the substrings `PS_FontInfo' and
`PS_Font_Info' in your source code. If none is found, your code
is safe and is not affected.
The FreeType team apologizes for the problem.
- The POSIX support of MacOS resource-fork fonts (Suitcase fonts
and LaserWriter Type1 PostScript fonts) was broken in 2.3.8. If
FreeType2 is built without Carbon framework, these fonts are not
handled correctly. Version 2.3.7 didn't have this bug.
- `FT_Get_Advance' (and `FT_Get_Advances') returned bad values for
almost all font formats except TrueType fonts.
- Fix a bug in the SFNT kerning table loader/parser which could
crash the engine if certain malformed tables were encountered.
- Composite SFNT bitmaps are now handled correctly.
II. IMPORTANT CHANGES
- The new functions `FT_Get_CID_Is_Internally_CID_keyed' and
`FT_Get_CID_From_Glyph_Index' can be used to access CID-keyed
CFF fonts via CID values. This code has been contributed by
Michael Toftdal.
III. MISCELLANEOUS
- `FT_Outline_Get_InsideBorder' returns FT_STROKER_BORDER_RIGHT
for empty outlines. This was incorrectly documented.
- The `ftview' demo program now supports UTF-8 encoded strings.
======================================================================
CHANGES BETWEEN 2.3.8 and 2.3.7
I. IMPORTANT BUG FIXES
- CID-keyed fonts in an SFNT wrapper were not handled correctly.
- The smooth renderer produced truncated images (on the right) for
outline parts with negative horizontal values. Most fonts don't
contain outlines left to the y coordinate axis, but the effect
was very noticeable for outlines processed with FT_Glyph_Stroke,
using thick strokes.
- `FT_Get_TrueType_Engine_Type' returned a wrong value if both
configuration macros TT_CONFIG_OPTION_BYTECODE_INTERPRETER and
TT_CONFIG_OPTION_UNPATENTED_HINTING were defined.
- The `face_index' field in the `FT_Face' structure wasn't
initialized properly after calling FT_Open_Face and friends with
a positive face index for CFFs, WinFNTs, and, most importantly,
for TrueType Collections (TTCs).
II. IMPORTANT CHANGES
- Rudimentary support for Type 1 fonts and CID-keyed Type 1 fonts
in an SFNT wrapper has been added -- such fonts are used on the
Mac. The core SFNT tables `TYP1' and `CID ' are passed to the
PS Type 1 and CID-keyed PS font drivers; other tables (`ALMX',
`BBOX', etc.) are not supported yet.
- A new interface to extract advance values of glyphs without
loading their outlines has been added. The functions are called
`FT_Get_Advance' and `FT_Get_Advances'; they are defined in file
`ftadvanc.h' (to be accessed as FT_ADVANCES_H).
- A new function `FT_Get_FSType_Flags' (in FT_FREETYPE_H) has been
contributed by David Bevan to access the embedding and
subsetting restriction information of fonts.
III. MISCELLANEOUS
- FT_MulFix is now an inlined function; by default, assembler code
is provided for x86 and ARM. See FT_CONFIG_OPTION_INLINE_MULFIX
and FT_CONFIG_OPTION_NO_ASSEMBLER (in ftoption.h) for more.
- The handling of `tricky' fonts (this is, fonts which don't work
with the autohinter, needing the font format's hinting engine)
has been generalized and changed slightly:
. A new face flag FT_FACE_FLAG_TRICKY indicates that the font
format's hinting engine is necessary for correct rendering.
The macro FT_IS_TRICKY can be used to check this flag.
. FT_LOAD_NO_HINTING is now ignored for tricky fonts. To really
force raw loading of such fonts (without hinting), both
FT_LOAD_NO_HINTING and FT_LOAD_NO_AUTOHINT must be used --
this is something which you probably never want to do.
. Tricky TrueType fonts always use the bytecode interpreter,
either the patented or unpatented version.
- The function `FT_GlyphSlot_Own_Bitmap' has been moved from
FT_SYNTHESIS_H to FT_BITMAP_H; it is now part of the `official'
API. (The functions in FT_SYNTHESIS_H are still subject to
change, however.)
- In the `ftdiff' demo program you can now toggle the use of
FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH with key `a'.
======================================================================
CHANGES BETWEEN 2.3.7 and 2.3.6
I. IMPORTANT BUG FIXES
- If the library was compiled on an i386 platform using gcc, and
compiler option -O3 was given, `FT_MulFix' sometimes returned
incorrect results which could have caused problems with
`FT_Request_Metrics' and `FT_Select_Metrics', returning an
incorrect descender size.
- Pure CFFs without subfonts were scaled incorrectly if the font
matrix was non-standard. This bug has been introduced in
version 2.3.6.
- The `style_name' field in the `FT_FaceRec' structure often
contained a wrong value for Type 1 fonts. This misbehaviour
has been introduced in version 2.3.6 while trying to fix
another problem. [Note, however, that this value is
informative only since the used algorithm to extract it is
very simplistic.]
II. IMPORTANT CHANGES
- Two new macros, FT_OUTLINE_SMART_DROPOUTS and
FT_OUTLINE_EXCLUDE_STUBS, have been introduced. Together with
FT_OUTLINE_IGNORE_DROPOUTS (which was ignored previously) it is
now possible to control the dropout mode of the `raster' module
(for B&W rasterization), using the `flags' field in the
`FT_Outline' structure.
- The TrueType bytecode interpreter now passes the dropout mode to
the B&W rasterizer. This greatly increases the output for small
ppem values of many fonts like `pala.ttf'.
======================================================================
CHANGES BETWEEN 2.3.6 and 2.3.5
I. IMPORTANT BUG FIXES
- A bunch of potential security problems have been found. All
users should update.
- Microsoft Unicode cmaps in TrueType fonts are now always
preferred over Apple cmaps. This is not a bug per se, but there
exist some buggy fonts created for MS which have broken Apple
cmaps. This affects only the automatic selection of FreeType;
it's always possible to manually select an Apple Unicode cmap if
desired.
- Many bug fixes to the TrueType bytecode interpreter.
- Improved Mac support.
- Subsetted CID-keyed CFFs are now supported correctly.
- CID-keyed CFFs with subfonts which are scaled in a non-standard
way are now handled correctly.
- A call to FT_Open_Face with `face_index' < 0 crashed FreeType if
the font was a Windows (bitmap) FNT/FON.
II. IMPORTANT CHANGES
- The new function `FT_Get_CID_Registry_Ordering_Supplement' gives
access to those fields in a CID-keyed font. The code has been
contributed by Derek Clegg.
- George Williams contributed code to validate the new `MATH'
OpenType table (within the `otvalid' module). The `ftvalid'
demo program has been extended accordingly.
- An API for cmap 14 support (for Unicode Variant Selectors, UVS)
has been contributed by George Williams.
- A new face flag FT_FACE_FLAG_CID_KEYED has been added, together
with a macro FT_IS_CID_KEYED which evaluates to 1 if the font is
CID-keyed.
III. MISCELLANEOUS
- Build support for symbian has been contributed.
- Better WGL4 glyph name support, contributed by Sergey Tolstov.
- Debugging output of the various FT_TRACEX macros is now sent to
stderr.
- The `ftview' demo program now provides artificial slanting too.
- The `ftvalid' demo program has a new option `-f' to select the
font index.
======================================================================
CHANGES BETWEEN 2.3.5 and 2.3.4
I. IMPORTANT BUG FIXES
- Some subglyphs in TrueType fonts were handled incorrectly due to
a missing graphics state reinitialization.
- Large .Z files (as distributed with some X11 packages) weren't
handled correctly, making FreeType increase the heap stack in an
endless loop.
- A large number of bugs have been fixed to avoid crashes and
endless loops with invalid fonts.
II. IMPORTANT CHANGES
- The two new cache functions `FTC_ImageCache_LookupScaler' and
`FTC_SBit_Cache_LookupScaler' have been added to allow lookup of
glyphs using an `FTC_Scaler' object; this makes it possible to
use fractional pixel sizes in the cache. The demo programs have
been updated accordingly to use this feature.
- A new API `FT_Get_CMap_Format' has been added to get the cmap
format of a TrueType font. This is useful in handling PDF
files. The code has been contributed by Derek Clegg.
- The auto-hinter now produces better output by default for
non-Latin scripts like Indic. This was done by using the CJK
hinting module as the default instead of the Latin one. Thanks
to Rahul Bhalerao for this suggestion.
- A new API `FT_Face_CheckTrueTypePatents' has been added to find
out whether a given TrueType font uses patented bytecode
instructions. The `ft2demos' bundle contains a new program
called `ftpatchk' which demonstrates its usage.
- A new API `FT_Face_SetUnpatentedHinting' has been added to
enable or disable the unpatented hinter.
- Support for Windows FON files in PE format has been contributed
by Dmitry Timoshkov.
III. MISCELLANEOUS
- Vincent Richomme contributed Visual C++ project files for Pocket
PCs.
======================================================================
CHANGES BETWEEN 2.3.4 and 2.3.3
I. IMPORTANT BUG FIXES
- A serious bug in the handling of bitmap fonts (and bitmap
strikes of outline fonts) has been introduced in 2.3.3.
======================================================================
CHANGES BETWEEN 2.3.3 and 2.3.2
I. IMPORTANT BUG FIXES
- Remove a serious regression in the TrueType bytecode interpreter
that was introduced in version 2.3.2. Note that this does not
disable the improvements introduced to the interpreter in
version 2.3.2, only some ill cases that occurred with certain
fonts (though a few popular ones).
- The auto-hinter now ignores single-point contours for computing
blue zones. This bug created `wavy' baselines when rendering
text with various fonts that use these contours to model
mark-attach points (these are points that are never rasterized
and are placed outside of the glyph's real outline).
- The `rsb_delta' and `lsb_delta' glyph slot fields are now set to
zero for mono-spaced fonts. Otherwise code that uses them would
essentially ruin the fixed-advance property.
- Fix CVE-2007-1351 which can cause an integer overflow while
parsing BDF fonts, leading to a potentially exploitable heap
overflow condition.
II. MISCELLANEOUS
- Fixed compilation issues on some 64-bit platforms (see ChangeLog
for details).
- A new demo program `ftdiff' has been added to compare TrueType
hinting, FreeType's auto hinting, and rendering without hinting
in three columns.
======================================================================
CHANGES BETWEEN 2.3.2 and 2.3.1
I. IMPORTANT BUG FIXES
- FreeType returned incorrect kerning information from TrueType
fonts when the bytecode interpreter was enabled. This happened
due to a typo introduced in version 2.3.0.
- Negative kerning values from PFM files are now reported
correctly (they were read as 16-bit unsigned values from the
file).
- Fixed a small memory leak when `FT_Init_FreeType' failed for
some reason.
- The Postscript hinter placed and sized very thin and ghost stems
incorrectly.
- The TrueType bytecode interpreter has been fixed to get rid of
most of the rare differences seen in comparison to the Windows
font loader.
II. IMPORTANT CHANGES
- The auto-hinter now better deals with serifs and corner cases
(e.g., glyph '9' in Arial at 9pt, 96dpi). It also improves
spacing adjustments and doesn't change widths for non-spacing
glyphs.
- Many Mac-specific functions are deprecated (but still
available); modern replacements have been provided for them.
See the documentation in file `ftmac.h'.
======================================================================
CHANGES BETWEEN 2.3.1 and 2.3.0
I. IMPORTANT BUG FIXES
- The TrueType interpreter sometimes returned incorrect horizontal
metrics due to a bug in the handling of the SHZ instruction.
- A typo in a security check introduced after version 2.2.1
prevented FreeType to render some glyphs in CFF fonts.
======================================================================
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.
======================================================================
CHANGES BETWEEN 2.2.1 and 2.2
I. IMPORTANT BUG FIXES
- Various integer overflows have been fixed.
- PFB fonts with MacOS resource fork weren't handled correctly on
non-MacOS platforms.
======================================================================
CHANGES BETWEEN 2.2 and 2.1.10
(not released officially)
I. IMPORTANT BUG FIXES
- Vertical metrics for SFNT fonts were incorrect sometimes.
- The FT_HAS_KERNING macro always returned 0.
- CFF OpenType fonts didn't return correct vertical metrics for
glyphs with outlines.
- If FreeType was compiled without hinters, all font formats based
on PS outlines weren't scaled correctly.
II. IMPORTANT CHANGES
- Version 2.2 no longer exposes its internals, this is, the header
files located in the `include/freetype/internal' directory of
the source package are not copied anymore by the `make install'
command. Consequently, a number of rogue clients which directly
access FreeType's internal functions and structures won't
compile without modification.
We provide patches for most of those rogue clients. See the
following page for more information:
http://www.freetype.org/freetype2/patches/rogue-patches.html
Note that, as a convenience to our Unix desktop users, version
2.2 is *binary* compatible with FreeType 2.1.7, which means that
installing this release on an existing distribution shall not
break any working desktop.
- FreeType's build mechanism has been redesigned. With GNU make
it is now sufficient in most cases to edit two files:
`modules.cfg', to select the library components, and the
configuration file `include/freetype/config/ftoption.h' (which
can be copied to the objects directory). Removing unused module
directories to prevent its compilation and editing
`include/freetype/config/ftmodule.h' is no longer necessary.
- The LIGHT hinting algorithm produces more pleasant results.
Also, using the FT_LOAD_TARGET_LIGHT flags within FT_Load_Glyph
always forces auto-hinting, as a special exception. This allows
you to experiment with it even if you have enabled the TrueType
bytecode interpreter in your build.
- The auto hinter now employs a new algorithm for CJK fonts, based
on Akito Hirai's patch. Note that this only works for fonts
with a Unicode charmap at the moment.
- The following callback function types have changed slightly (by
adding the `const' keyword where appropriate):
FT_Outline_MoveToFunc
FT_Outline_LineToFunc
FT_Outline_ConicToFunc
FT_Outline_CubicToFunc
FT_SpanFunc
FT_Raster_RenderFunc
FT_Glyph_TransformFunc
FT_Renderer_RenderFunc
FT_Renderer_TransformFunc
Note that this doesn't affect binary backward compatibility.
- On MacOS, new APIs have been added as replacements for legacy
APIs: `FT_New_Face_From_FSRef' for `FT_New_Face_From_FSSpec',
and `FT_GetFile_From_Mac_ATS_Name' for
`FT_GetFile_From_Mac_Name'. Legacy APIs are still available, if
FreeType is built without disabling them.
- A new API `FT_Select_Size' has been added to select a bitmap
strike by its index. Code using other functions to select
bitmap strikes should be updated to use this function.
- A new API `FT_Get_SubGlyph_Info' has been added to retrieve
subglyph data. This can be used by rogue clients which used to
access the internal headers to get the corresponding data.
- In 2.1.10, the behaviour of `FT_Set_Pixel_Sizes' was changed for
BDF/PCF fonts, and only for them. This causes inconsistency.
In this release, we undo the change. The intent of the change
in 2.1.10 is to allow size selection through real dimensions,
which can now be done through `FT_Request_Size'.
- Some security issues were discovered and fixed in the CFF and
Type 1 loader, causing crashes of FreeType by malformed font
files.
III. MISCELLANEOUS
- The documentation for FT_LOAD_TARGET_XXX and FT_RENDER_MODE_XXX
values now better reflects its usage and differences: One set is
used to specify the hinting algorithm, the other to specify the
pixel rendering mode.
- `FT_New_Face' and `FT_New_Face_From_FSSpec' in ftmac.c have been
changed to count supported scalable faces (sfnt, LWFN) only, and
to return the number of available faces via face->num_faces.
Unsupported bitmap faces (fbit, NFNT) are ignored.
- builds/unix/configure has been improved for MacOS X. It now
automatically checks available functions in Carbon library, and
prepare to use newest functions by default. Options to specify
the dependencies of each Carbon APIs (FSSpec, FSRef, old/new
QuickDraw, ATS) are available too. By manual disabling of all
QuickDraw functionality, FreeType can be built without
`deprecated function' warnings on MacOS 10.4.x, but
FT_GetFile_Mac_Name in ftmac.c then is changed to a dummy
function, and returns an `unimplemented' error. For details see
builds/mac/README.
- SFNT cmap handling has been improved, mainly to run much faster
with CJK fonts.
- A new function `FT_Get_TrueType_Engine_Type (declared in
`FT_MODULE_H') is provided to determine the status of the
TrueType bytecode interpreter compiled into the library
(patented, unpatented, unimplemented).
- Vertical metrics of glyphs are synthesized if the font does not
provide such information. You can tell whether the metrics are
synthesized or not by checking the FT_FACE_FLAG_VERTICAL flag of
the face.
- The demo programs `ftview' and `ftstring' have been rewritten
for better readability. `ftview' has a new switch `-p' to test
FT_New_Memory_Face (instead of FT_New_Face).
- FreeType now honours bit 1 in the `head' table of TrueType fonts
(meaning `left sidebearing point at x=0'). This helps with some
buggy fonts.
- Rudimentary support for Adobe's new `SING Glyphlet' format. See
http://www.adobe.com/products/indesign/sing_gaiji.html
for more information.
- The `ftdump' program from the `ft2demos' bundle now shows some
information about charmaps. It also supports a new switch `-v'
to increase verbosity.
- Better AFM support. This includes track kerning support.
======================================================================
CHANGES BETWEEN 2.1.10 and 2.1.9
I. IMPORTANT BUG FIXES
- The size comparison for BDF and PCF files could fail sometimes.
- Some CFF files were still not loaded correctly. Patch from
Derek Noonburg.
- The stroker still had some serious bugs.
- Boris Letocha fixed a bug in the TrueType interpreter: The
NPUSHW instruction wasn't skipped correctly in IF clauses. Some
fonts like `Helvetica 75 Bold' failed.
- Another serious bug in handling TrueType hints caused many
distortions. It has been introduced in version 2.1.8, and it is
highly recommended to upgrade.
- FreeType didn't properly parse empty Type 1 glyphs.
- An unbound dynamic buffer growth was fixed in the PFR loader.
- Several bugs have been fixed in the cache sub-system.
- FreeType behaved incorrectly when resizing two distinct but very
close character pixel sizes through `FT_Set_Char_Size' (Savannah
bug #12263).
- The auto-hinter didn't work properly for fonts without a Unicode
charmap -- it even refused to load the glyphs.
II. IMPORTANT CHANGES
- Many fixes have been applied to drastically reduce the amount of
heap memory used by FreeType, especially when using
memory-mapped font files (which is the default on Unix systems
which support them).
- The auto-hinter has been replaced with a new module, called the
`auto-fitter'. It consumes less memory than its predecessor,
and it is prepared to support non-latin scripts better in next
releases.
- George Williams contributed code to read kerning data from PFM
files.
- FreeType now uses the TT_NAME_ID_PREFERRED_FAMILY and
TT_NAME_ID_PREFERRED_SUBFAMILY strings (if available) for
setting family and style in SFNT fonts (patch from Kornfeld
Eliyahu Peter).
- A new API `FT_Sfnt_Table_Info' (in FT_TRUETYPE_TABLES_H) has
been added to retrieve name and size information of SFNT tables.
- A new API `FT_OpenType_Validate' (in FT_OPENTYPE_VALIDATE_H) has
been added to validate OpenType tables (BASE, GDEF, GPOS, GSUB,
JSTF). After validation it is no longer necessary to check
for errors in those tables while accessing them.
Note that this module might be moved to another library in the
future to avoid a tight dependency between FreeType and the
OpenType specification.
- A new API in FT_BITMAP_H (`FT_Bitmap_New', `FT_Bitmap_Convert',
`FT_Bitmap_Copy', `FT_Bitmap_Embolden', `FT_Bitmap_Done') has
been added. Its use is to convert an FT_Bitmap structure in
1bpp, 2bpp, 4bpp, or 8bpp format into another 8bpp FT_Bitmap,
probably using a different pitch, and to further manipulate it.
- A new API `FT_Outline_Embolden' (in FT_OUTLINE_H) gives finer
control how outlines are embolded.
- `FT_GlyphSlot_Embolden' (in FT_SYNTHESIS_H) now handles bitmaps
also (code contributed by Chia I Wu). Note that this function
is still experimental and may be replaced with a better API.
- The method how BDF and PCF bitmap fonts are accessed has been
refined. Formerly, FT_Set_Pixel_Sizes and FT_Set_Char_Size
were synonyms in FreeType's BDF and PCF interface. This has
changed now. FT_Set_Pixel_Sizes should be used to select the
actual font dimensions (the `strike', which is the sum of the
`FONT_ASCENT' and `FONT_DESCENT' properties), while
FT_Set_Char_Size selects the `nominal' size (the `PIXELSIZE'
property). In both functions, the width parameter is ignored.
III. MISCELLANEOUS
- The BDF driver no longer converts all returned bitmaps with a
depth of 2bpp or 4bpp to a depth of 8bpp. The documentation has
not mentioned this explicitly, but implementors might have
relied on this after looking into the source files.
- A new option `--ftversion' has been added to freetype-config to
return the FreeType version.
- The memory debugger has been updated to dump allocation
statistics on all allocation sources in the library. This is
useful to spot greedy allocations when loading and processing
fonts.
- We removed a huge array of constant pointers to constant strings
in the `psnames' module. The problem was that compilations in
PIC mode (i.e., when generating a Unix shared object/dll) put
the array into the non-shared writable section of the library
since absolute pointers are not relocatable by nature.
This reduces the memory consumption by approximately 16KByte per
process linked to FreeType. We now also store the array in a
compressed form (as a trie) which saves about 20KByte of code as
well.
- Kirill Smelkov provided patches to make src/raster/ftraster.c
compile stand-alone again.
======================================================================
CHANGES BETWEEN 2.1.9 and 2.1.8
I. IMPORTANT BUG FIXES
- The function `FT_Get_CharMap_Index' was only declared, without
any real code. For consistency, it has been renamed to
`FT_Get_Charmap_Index'. (This function is needed to implement
cmap caches.)
- `FT_Outline_Get_BBox' sometimes returned incorrect values for
conic outlines (e.g., for TrueType fonts).
- Handling of `bhed' table has been fixed.
- The TrueType driver with enabled byte code interpreter sometimes
returned artifacts due to incorrect rounding. This bug has been
introduced after version 2.1.4.
- The BDF driver dropped the last glyph in the font.
- The BDF driver now uses the DEFAULT_CHAR property (if available)
to select a glyph shape for the undefined glyph.
- The stroker failed for closed outlines and single points.
II. IMPORTANT CHANGES
- George Williams contributed code to handle Apple's font
distortion technology found in GX fonts (`avar', `cvar', `fvar',
and `gvar' tables; the Multiple Masters API has been slightly
extended to cope with the new functionality).
- The `FT_GlyphSlotRec' structure has been extended: The elements
`lsb_delta' and `rsb_delta' give the difference between hinted
and unhinted left and right side bearings if autohinting is
active. Using those values can improve the inter-letter spacing
considerably. See the documentation of `FT_GlyphSlotRec' and
the `ftstring' demo program how to use it.
- Loading TrueType and Type 1 fonts has been made much faster.
- The stroker is no longer experimental (but the cache subsystem
still is).
III. MISCELLANEOUS
- A new documentation file `formats.txt' describes various font
formats supported (and not supported) by FreeType.
======================================================================
CHANGES BETWEEN 2.1.8 and 2.1.7
I. IMPORTANT BUG FIXES
- The native TrueType hinter contained some bugs which prevented
some fonts to be rendered correctly, most notably Legendum.otf.
- The PostScript hinter now produces improved results.
- The linear advance width and height values were incorrectly
rounded, making them virtually unusable if not loaded with
FT_LOAD_LINEAR_DESIGN.
- Indexing CID-keyed CFF fonts is now working: The glyph index is
correctly treated as a CID, similar to FreeType's CID driver
module. Note that CID CMap support is still missing.
- The FT_FACE_FLAGS_GLYPH_NAMES flag is now set correctly for all
font formats.
- Some subsetted Type 1 fonts weren't parsed correctly. This bug
has been introduced in 2.1.7. In summary, the Type 1 parser has
become more robust.
- Non-decimal numbers weren't parsed correctly in PS fonts.
- The WinFNT driver now correctly reports FT_ENCODING_NONE for all
but one encoding. Use the new FT_WinFNT_ID_XXX values together
with `FT_Get_WinFNT_Header' to get the WinFNT charset ID.
- The descender metrics (face->size->metrics.descender) for WinFNT
bitmap fonts had the wrong sign.
- The (emulated) `seac' support for CFF fonts was broken.
- The `flex' operator didn't work for CFF fonts.
- PS glyphs which use the `hintmask' operator haven't been
rendered correctly in some cases.
- Metrics for BDF and PCF bitmap font formats have been fixed.
- Autohinting is now disabled for glyphs which are vertically
distorted or mirrored (using a transformation matrix). This
fixes a bug which produced zero-height glyphs.
- The `freetype-config' script now handles --prefix and
--exec-prefix correctly; it also returns the proper --rpath (or
-R) value if FreeType has been built as a shared library.
II. IMPORTANT CHANGES
- Both PCF and BDF drivers now handle the SETWIDTH_NAME and
ADD_STYLE_NAME properties. Values are appended to
face->style_name; example: `Bold SemiCondensed'.
- The PCF driver now handles bitmap fonts compressed with the LZW
algorithm (extension .pcf.Z, compressed with `compress').
- A new API function `FT_Get_CMap_Language_ID' (declared in
`tttables.h') is available to get the language ID of a
TrueType/SFNT cmap.
- The hexadecimal format of data after the `StartData' command in
CID-keyed Type 1 fonts is now supported. While this can't occur
in file-based fonts, it can happen in document-embedded
resources of PostScript documents.
- Embedded bitmaps in SFNT-based CFF fonts are now supported.
- A simple API is now available to control FreeType's tracing
mechanism if compiled with FT_DEBUG_LEVEL_TRACE. See the file
`ftdebug.h' for more details.
- YAMATO Masatake contributed improved handling of MacOS resource
forks on non-MacOS platforms (for example, Linux can mount MacOS
file systems).
- Support for MacOS has been improved; there is now a new function
`FT_New_Face_From_FSSpec' similar to `FT_New_Face' except that
it accepts an FSSpec instead of a path.
- The cache sub-system has been rewritten.
- There is now support for deinstallation of faces.
- A new API function `FTC_Manager_RemoveFaceID' has been added
to delete all `idle' nodes that correspond to a given
FTC_FaceID. All `locked' nodes (i.e., those with a reference
count > 0), will be modified to prevent them from appearing in
further lookups (they will be cleaned normally when their
reference count reaches 0).
- There is now support for point scaling (i.e., providing
character sizes in points + dpis, instead of pixels).
- Three abstract cache classes are now available:
FTC_GCache: Used to store one glyph item per cache node,
with the ability to group common attributes into
`families'. This replaces the old
FTC_GlyphCache class.
FTC_ICache: Used to store one FT_Glyph per cache node. This
extends FTC_GCache. Family definition, family
comparison, and glyph loading are however left
to sub-classes.
FTC_SCache: Used to store up to 16 small bitmaps per cache
node. This extends FTC_GCache. Family
definition, family comparison and glyph loading
are however left to sub-classes.
- The file `src/cache/ftcbasic.c' implements:
FTC_ImageCache: Extends FTC_ICache; implements family
definitions and glyph loading similar to the
old API.
FTC_SBitCache: Extends FTC_SCache, implements family
definitions and glyph loading similar to the
old API
Client applications should be able to extend FTC_GCache,
FTC_ICache, or FTC_SCache much more easily (i.e., less code to
write, and less callbacks). For example, one could envision
caches that are capable of storing transformed (obliqued),
stroked, emboldened, or colored glyph images. Use
`ftcbasic.c' as an example.
- All public APIs are now in `include/freetype/ftcache.h', (to
be accessed as `FT_CACHE_H'). The contents of
`include/freetype/cache/' is only needed by applications that
wish to implement their own caches.
- There were some major performance improvements through the use
of various programming tricks. Cache hits are up to 70%
faster than in the old code.
- The FTC_CMapCache has been simplified. Charmaps can only be
accessed by index right now. There is also a new API named
`FT_Charmap_GetIndex' for this purpose.
- The demo programs have been updated to the new code. The
previous versions will not work with the current one.
- Using an invalid face index in FT_Open_Face and friends now
causes an error even if the font contains a single face only.
III. MISCELLANEOUS
- Wolfgang Domröse contributed support files for building FreeType
on the Atari using the PureC compiler. Note that the Atari is a
16bit platform.
- Vitaliy Pasternak contributed project files for VS.NET 2003.
======================================================================
CHANGES BETWEEN 2.1.7 and 2.1.6
I. IMPORTANT BUG FIXES
- Updated to newest libtool version, fixing build problems on
various platforms.
- On Unix platforms, `make install' didn't copy the correct
`ftconfig.h' file.
Note that version 2.1.7 contains the same library C source code as
version 2.1.6.
======================================================================
CHANGES BETWEEN 2.1.6 and 2.1.5
I. IMPORTANT BUG FIXES
- The PFR font driver didn't load kerning tables correctly, and
the functions in FT_PFR_H didn't work at all.
- Type 1 font files in binary format (PFB) with an end-of-file
indicator weren't accepted by the FreeType engine.
- Fonts which contain /PaintType and /StrokeWidth no longer cause
a segfault. This bug has been introduced in version 2.1.5.
- Fonts loaded with FT_LOAD_RENDER no longer cause strange
results. This bug has been introduced in version 2.1.5.
- Some Windows (bitmap) FNT/FON files couldn't be handled
correctly.
II. IMPORTANT CHANGES
- The internal module API has been heavily changed in favor of
massive simplifications within the font engine. This also means
that authors of third-party modules must adapt their code to the
new scheme.
NOTE: THE NEW SCHEME IS NOT COMPLETED YET. PLEASE WAIT UNTIL A
FINAL ANNOUNCEMENT!
- The PostScript parser has been enhanced to handle comments and
strings correctly. Additionally, more syntax forms are
recognized.
- Added the optional unpatented hinting system for TrueType. It
allows typefaces which need hinting to produce correct glyph
forms (e.g., Chinese typefaces from Dynalab) to work acceptably
without infringing Apple patents. This system is compiled only
if TT_CONFIG_OPTION_COMPILE_UNPATENTED_HINTING is defined in
ftoption.h (activated by default).
III. MISCELLANEOUS
- There is now a guard in the public header files to protect
against inclusion of freetype.h from FreeType 1.
- Direct inclusion of freetype.h and other public header files no
longer works. You have to use the documented scheme
#include <ft2build.h>
#include FT_FREETYPE_H
to load freetype.h with a symbolic name. This protects against
renaming of public header files (which shouldn't happen but
actually has, avoiding two public header files with the same
name).
======================================================================
CHANGES BETWEEN 2.1.5 and 2.1.4
I. IMPORTANT BUG FIXES
- Parsing the /CIDFontName field now removes the leading slash to
be in sync with other font drivers.
- gzip support was buggy. Some fonts could not be read.
- Fonts which have nested subglyphs more than one level deep no
longer cause a segfault.
- Creation of synthetic cmaps for fonts in CFF format was broken
partially.
- Numeric font dictionary entries for synthetic fonts are no
longer overwritten.
- The font matrix wasn't applied to the advance width for Type1,
CID, and CFF fonts. This caused problems when loading certain
synthetic Type 1 fonts like `Helvetica Narrow'.
- The test for the charset registry in BDF and PCF fonts is now
case-insensitive.
- FT_Vector_Rotate sometimes returned strange values due to
rounding errors.
- The PCF driver now returns the correct number of glyphs
(including an artificial `notdef' glyph at index 0).
- FreeType now supports buggy CMaps which are contained in many
CJK fonts from Dynalab.
- Opening an invalid font on a Mac caused a segfault due to
double-freeing memory.
- BDF fonts with more than 32768 glyphs weren't supported
properly.
II. IMPORTANT CHANGES
- Accessing bitmap font formats has been synchronized. To do that
the FT_Bitmap_Size structure has been extended to contain new
fields `size', `x_ppem', and `y_ppem'.
- The FNT driver now returns multiple faces, not multiple strikes.
- The `psnames' module has been updated to the Adobe Glyph List
version 2.0.
- The `psnames' module now understands `uXXXX[X[X]]' glyph names.
- The algorithm for guessing the font style has been improved.
- For fonts in SFNT format, root->height is no longer increased if
the line gap is zero. There exist fonts (containing e.g. form
drawing characters) which intentionally have a zero line gap
value.
- ft_glyph_bbox_xxx flags are now deprecated in favour of
FT_GLYPH_BBOX_XXX.
- ft_module_xxx flags are now deprecated in favour of
FT_MODULE_XXX.
- FT_ENCODING_MS_{SJIS,GB2312,BIG5,WANSUNG,JOHAB} are now
deprecated in favour of
FT_ENCODING_{SJIS,GB2312,GIB5,WANSONG,JOHAB} -- those encodings
are not specific to Microsoft.
III. MISCELLANEOUS
- The autohinter has been further improved; for example, `m'
glyphs now retain its vertical symmetry.
- Partial support of Mac fonts on non-Mac platforms.
- `make refdoc' (after first `make') builds the HTML
documentation. You need Python for this.
- The make build system should now work more reliably on DOS-like
platforms.
- Support for EMX gcc and Watson C/C++ compilers on MS-DOS has
been added.
- Better VMS build support.
- Support for the pkg-config package by providing a `freetype.pc'
file.
- New configure option --with-old-mac-fonts for Darwin.
- Some source files have been renamed (mainly to fit into the 8.3
naming scheme).
======================================================================
CHANGES BETWEEN 2.1.4 and 2.1.3
I. IMPORTANT BUG FIXES
- Updated to newest libtool version, fixing build problems on
various platforms.
- A fix in the Gzip stream reader: It couldn't read certain .gz
files properly due to a small typo. In certain cases, FreeType
could also loop endlessly when trying to load tiny gzipped
files.
- The configure script now tries to use the system-wide zlib when
it finds one (instead of the copy found in src/gzip). And
`freetype-config' has been updated to return relevant flags in
this case when invoked with `--libs' (e.g. `-lzlib').
- Certain fonts couldn't be loaded by 2.1.3 because they lacked a
Unicode charmap (e.g. SYMBOL.TTF). FreeType erroneously
rejected them.
- The CFF loader was modified to accept fonts which only contain a
subset of their reference charset. This prevented the correct
use of PDF-embedded fonts.
- The logic to detect Unicode charmaps has been modified. This is
required to support fonts which include both 16-bit and 32-bit
charmaps (like very recent asian ones) using the new 10 and 12
SFNT formats.
- The TrueType loader now limits the depth of composite glyphs.
This is necessary to prevent broken fonts to break the engine by
blowing the stack with recursive glyph definitions.
- The CMap cache is now capable of managing UCS-4 character codes
that are mapped through extended charmaps in recent
TrueType/OpenType fonts.
- The cache sub-system now properly manages out-of-memory
conditions instead of blindly reporting them to the caller.
This means that it will try to empty the cache before restarting
its allocations to see if that can help.
- The PFR driver didn't return the list of available embedded
bitmaps properly.
- There was a nasty memory leak when using embedded bitmaps in
certain font formats.
II. IMPORTANT CHANGES
- David Chester contributed some enhancements to the auto-hinter
that significantly increase the quality of its output. The
Postscript hinter was also improved in several ways.
- The FT_RENDER_MODE_LIGHT render mode was implemented.
- A new API function called `FT_Get_BDF_Property' has been added
to FT_BDF_H to retrieve BDF properties from BDF _and_ PCF font
files. THIS IS STILL EXPERIMENTAL, since it hasn't been
properly tested yet.
- A Windows FNT specific API has been added, mostly to access font
headers. This is used by Wine.
- TrueType tables without an `hmtx' table are now tolerated when
an incremental interface is used. This happens for certain
Type42 fonts passed from Ghostscript to FreeType.
- The PFR font driver is now capable of returning the font family
and style names when they are available (instead of the sole
`FontID'). This is performed by parsing an *undocumented*
portion of the font file!
III. MISCELLANEOUS
- The path stroker in FT_STROKER_H has entered beta stage. It now
works very well, but its interface might change a bit in the
future. More on this in later releases.
- The documentation for FT_Size_Metrics didn't appear properly in
the API reference.
- The file docs/VERSION.DLL has been updated to explain versioning
with FreeType (i.e., comparing release/libtool/so numbers, and
how to use them in autoconf scripts).
- The installation documentation has been seriously revamped.
Everything is now in the `docs' directory.
======================================================================
CHANGES BETWEEN 2.1.3 and 2.1.2
I. IMPORTANT BUG FIXES
- FT_Vector_Transform had been incorrectly modified in 2.1.2,
resulting in incorrect transformations being applied (for
example, rotations were processed in opposite angles).
- The format 8 and 12 TrueType charmap enumeration routines have
been fixed (FT_Get_Next_Char returned invalid values).
- The PFR font driver returned incorrect advance widths if the
outline and metrics resolution defined in the font file were
different.
- FT_Glyph_To_Bitmap now returns successfully when called with an
FT_BitmapGlyph argument (it previously returned an error).
- A bug in the Type 1 loader that prevented valid font bounding
boxes to be loaded from multiple master fonts.
- The SFNT validation code has been rewritten. FreeType can now
load `broken' fonts that were usable on Windows, but not with
previous versions of the library.
- The computation of bearings in the BDF driver has been fixed.
- The Postscript hinter crashed when trying to hint certain glyphs
(more precisely, when trying to apply hints to an empty glyph
outline).
- The TrueType glyph loader now supports composites in `Apple
format' (they differ slightly from Microsoft/OpenType ones in
the way transformation offsets are computed).
- FreeType was very slow at opening certain asian CID/CFF fonts,
due to fixed increment in dynamic array re-allocations. This
has been changed to exponential behaviour to get acceptable
performance.
II. IMPORTANT CHANGES
- The PCF driver now supports gzip-compressed font files natively.
This means that you will be able to use all these bitmap fonts
that come with XFree86 with FreeType (and libXft/libXft2, by
extension).
- The automatic and postscript hinters have both been updated.
This results in a relatively important increase of rendering
quality since many nasty defaults have been suppressed. Please
visit the web page:
http://www.freetype.org/hinting/smooth-hinting.html
for additional details on this topic.
- The `load_flags' parameter of `FT_Load_Glyph' is now an FT_Int32
(instead of just being an FT_Int). This breaks source and
binary compatibility for 16bit systems only, while retaining
both of them for 32 and 64 bit ones.
Some new flags have been added consequently:
FT_LOAD_NO_AUTOHINT :: Disable the use of the auto-hinter
(but not native format hinters).
FT_LOAD_TARGET_NORMAL :: Hint and render for normal
anti-aliased displays.
FT_LOAD_TARGET_MONO :: Hint and render for 1-bit displays.
FT_LOAD_TARGET_LCD :: Hint and render for horizontal RGB or
BGR sub-pixel displays (like LCD
screens). THIS IS STILL
EXPERIMENTAL!
FT_LOAD_TARGET_LCD_V :: Same as FT_LOAD_TARGET_LCD, for
vertical sub-pixel displays (like
rotated LCD screens). THIS IS STILL
EXPERIMENTAL!
FT_LOAD_MONOCHROME is still supported, but only affects
rendering, not the hinting.
Note that the `ftview' demo program available in the `ft2demos'
package has been updated to support LCD-optimized display on
non-paletted displays (under Win32 and X11).
- The PFR driver now supports embedded bitmaps (all formats
supported), and returns correct kerning metrics for all glyphs.
- The TrueType charmap loader now supports certain `broken' fonts
that load under Windows without problems.
- The cache API has been slightly modified (it's still a beta!):
- The type FTC_ImageDesc has been removed; it is now replaced
by FTC_ImageTypeRec. Note that one of its fields is a
`load_flag' parameter for FT_Load_Glyph.
- The field `num_grays' of FT_SBitRec has been changed to
`max_grays' in order to fit within a single byte. Its
maximum value is thus 255 (instead of 256 as previously).
III. MISCELLANEOUS
- Added support for the DESTDIR variable during `make install'.
This simplifies packaging of FreeType.
- Included modified copies of the ZLib sources in `src/gzip' in
order to support gzip-compressed PCF fonts. We do not use the
system-provided zlib for now, though this is a probable
enhancement for future releases.
- The DocMaker tool used to generate the on-line API reference has
been completely rewritten. It is now located in
`src/tools/docmaker/docmaker.py'. Features:
- better cross-referenced output
- more polished output
- uses Python regular expressions (though it didn't speed the
program)
- much more modular structure, which allows for different
`backends' in order to generate HTML, XML, or whatever
format.
One can regenerate the API reference by calling:
python src/tools/docmaker/docmaker.py \
--prefix=ft2 \
--title=FreeType-2.1.3 \
--output=<outputdirectory>
include/freetype/*.h \
include/freetype/config/*.h \
include/freetype/cache/*.h
- A new, experimental, support for incremental font loading (i.e.,
loading of fonts where the glyphs are not in the font file
itself, but provided by an external component, like a Postscript
interpreter) has been added by Graham Asher. This is still work
in progress, however.
- A new, EXPERIMENTAL, path stroker has been added. It doesn't
suffer from severe rounding errors and treat bezier arcs
directly. Still work in progress (i.e. not part of the official
API). See the file <freetype/ftstroker.h> for some of the
details.
- The massive re-formatting of sources and internal re-design is
still under-way. Many internal functions, constants, and types
have been renamed.
======================================================================
CHANGES BETWEEN 2.1.2 and 2.1.1
I. IMPORTANT BUG FIXES
- Many font drivers didn't select a Unicode charmap by default
when a new face was opened (with the FT_CONFIG_OPTION_USE_CMAPS
options enabled), causing many applications to not be able to
display text correctly with the 2.1.x releases.
- The PFR driver had a bug in its composite loading code that
produces incorrectly placed accents with many fonts.
- The Type42 driver crashed sometimes due to a nasty bug.
- The Type 1 custom encoding charmap didn't handle the case where
the first glyph index wasn't 0.
- A serious typo in the TrueType composite loader produced
incorrectly placed glyphs in fonts like `Wingdings' and a few
others.
II. MISCELLANEOUS
- The Win32 Visual C++ project file has been updated to include
the PFR driver as well.
- `freetype.m4' is now installed by default by `make install' on
Unix systems.
- The function FT_Get_PS_Font_Info now works with CID and Type42
fonts as well.
======================================================================
CHANGES BETWEEN 2.1.1 and 2.1.0
I. IMPORTANT BUG FIXES
- The `version_info' returned by `freetype-config' in 2.1.0
returned an invalid value. It now returns 9:1:3 (2.0.9 returned
9:0:3).
- Version 2.1.0 couldn't be linked against applications on Win32
and Amiga systems due to a new debug function that wasn't
properly propagated to the system-specific directory in
`builds'.
- Various MacOS and Mac OS X specific fixes.
- Fixed a bug in the TrueType charmap validation routines that
made version 2.1.0 too restrictive -- many popular fonts have
been rejected.
- There was still a very small difference between the monochrome
glyph bitmaps produced by FreeType 1.x and FreeType 2.x with the
bytecode interpreter enabled. This was caused by an invalid
flag setting in the TrueType glyph loader, making the rasterizer
change its drop-out control mode. Now the results should
_really_ be completely identical.
- The TrueType name table loader has been improved to support many
popular though buggy Asian fonts. It now ignores empty name
entries, invalid pointer offsets and a few other incorrect
subtleties. Moreover, name strings are now loaded on demand,
which reduces the memory load of many faces (e.g. the ARIAL.TTF
font file contains a 10kByte name table with 70 names).
- Fixed a bug in the Postscript hinter that prevented family blues
substitution to happen correctly.
II. NEW FEATURES
- Three new font drivers in this release:
* A BDF font driver, contributed by Franco Zappa Nardelli,
heavily modified by Werner Lemberg. It also supports
anti-aliased bitmaps (using a slightly extended BDF format).
* A Type42 font driver, contributed by Roberto Alameda. It is
still experimental but seems to work relatively well.
* A PFR font driver, contributed by David Turner himself. It
doesn't support PFR hinting -- note that BitStream has at
least two patents on this format!
III. MISCELLANEOUS
- The cache sub-system has been optimized in important ways.
Cache hits are now significantly faster. For example, using the
CMap cache is about twice faster than calling FT_Get_Char_Index
on most platforms. Similarly, using an SBit cache is about five
times faster than loading the bitmaps from a bitmap file, and
300 to 500 times faster than generating them from a scalable
format.
Note that you should recompile your sources if you designed a
custom cache class for the FT2 Cache subsystem, since the
changes performed are source, but not binary, compatible.
======================================================================
CHANGES BETWEEN 2.1.0 and 2.0.9
I. IMPORTANT BUG FIXES
- The TrueType bytecode interpreter has been fixed to produce
_exactly_ the same output as FreeType 1.x. Previous differences
were due to slightly distinct fixed-point computation routines
used to perform dot products and vector length measurements.
It seems that native TrueType hinting is _extremely_ sensitive
to rounding errors. The required vector computation routines
have been optimized and placed within the `ttinterp.c' file.
- Fixed the parsing of accelerator tables in the PCF font driver.
- Fixed the Type1 glyph loader routine used to compute the font's
maximum advance width.
II. NEW FEATURES
- The `configure' script used on Unix systems has been modified to
check that GNU Make is being used to build the library.
Otherwise, it will display a message proposing to use the
GNUMAKE environment variable to name it.
The Unix-specific file README.UNX has been modified accordingly.
III. MISCELLANEOUS
- The FreeType License in `docs/FTL.TXT' has been updated to
include a proposed preferred disclaimer. If you are using
FreeType in your products, you are encouraged (but not mandated)
to use the following text in your documentation:
"""
Portions of this software are copyright © 1996-2002 The
FreeType Project (www.freetype.org). All rights reserved.
"""
- The default size of the render pool has been reduced to 16kByte.
This shouldn't result in any noticeable performance penalty,
unless you are using the engine as-is to render very large and
complex glyphs.
- The FreeType 2 redesign has begun. More information can be
found at this URL:
http://www.freetype.org/freetype2/redesign.html
The following internal changes have been performed within the
sources of this release:
- Many internal types have been renamed to increase
consistency. The following should be true, except for
public types:
* All structure types have a name ending in `Rec' (short
for `record').
* A pointer-to-structure type has the same name as the
structure, _without_ the `Rec' suffix.
Example:
typedef struct FooRec_
{
...
} FooRec, *Foo;
- Many internal macros have been renamed to increase
consistency. The following should be true:
* All macros have a name beginning with `FT_'. This
required a few changes like
ALLOC => FT_ALLOC
FREE => FT_FREE
REALLOC => FT_REALLOC
* All macros are completely UPPERCASE. This required a
few changes like:
READ_Short => FT_READ_SHORT
NEXT_Short => FT_NEXT_SHORT
GET_ULongLE => FT_GET_ULONG_LE
MEM_Set => FT_MEM_SET
MEM_Copy => FT_MEM_COPY
etc.
* Whenever possible, all macro names follow the
FT_<OBJECT>_<METHOD> pattern. For example
ACCESS_Frame => FT_FRAME_ENTER
FORGET_Frame => FT_FRAME_EXIT
EXTRACT_Frame => FT_FRAME_EXTRACT
RELEASE_Frame => FT_FRAME_RELEASE
FILE_Pos => FT_STREAM_POS
FILE_Seek => FT_STREAM_SEEK
FILE_Read => FT_STREAM_READ
FILE_ReadAt => FT_STREAM_READ_AT
READ_Fields => FT_STREAM_READ_FIELDS
- Many internal functions have been renamed to follow the
FT_<Object>_<Method> pattern. For example:
FT_Seek_Stream => FT_Stream_Seek
FT_Read_Stream_At => FT_Stream_ReadAt
FT_Done_Stream => FT_Stream_Close
FT_New_Stream => FT_Stream_Open
FT_New_Memory_Stream => FT_Stream_OpenMemory
FT_Extract_Frame => FT_Stream_ExtractFrame
Note that method names do not contain `_'.
- The FT_ALLOC_ARRAY and FT_REALLOC_ARRAY have been replaced
with FT_NEW_ARRAY and FT_RENEW_ARRAY which do not take a
type as the fourth argument. Instead, the array element
type size is computed automatically from the type of the
target pointer used.
- A new object class, FT_CMap, has been introduced. These
internal objects are used to model character maps. This
eases the support of additional charmap types within the
engine.
- A new configuration file named `ftstdlib.h' has been added
to `include/freetype/config'. It is used to define aliases
for _every_ routine of the ISO C library that the font
engine uses. Each aliases has a `ft_' prefix
(e.g. `ft_strlen' is an alias for `strlen').
This is used to ease the porting of FreeType 2 to exotic
runtime environments where the ISO C Library isn't available
(e.g. XFree86 extension modules).
More details are available in the `ChangeLog' file.
======================================================================
CHANGES BETWEEN 2.0.9 and 2.0.8
I. IMPORTANT BUG FIXES
- Certain fonts like `foxjump.ttf' contain broken name tables with
invalid entries and wild offsets. This caused FreeType to crash
when trying to load them.
The SFNT `name' table loader has been fixed to be able to
support these strange fonts.
Moreover, the code in charge of processing this table has been
changed to always favour Windows-formatted entries over other
ones. Hence, a font that works on Windows but not on the Mac
will load cleanly in FreeType and report accurate values for
Family & PostScript names.
- The CID font driver has been fixed. It unfortunately returned a
Postscript Font name with a leading slash, as in
`/MunhwaGothic-Regular'.
- FreeType 2 should now compile fine on AIX 4.3.3 as a shared
library.
- A bug in the Postscript hinter has been found and fixed,
removing un-even stem widths at small pixel sizes (like 14-17).
This improves the quality of a certain number of Postscript
fonts.
II. NEW FEATURES
- A new function named `FT_Library_Version' has been added to
return the current library's major, minor, and patch version
numbers. This is important since the macros FREETYPE_MAJOR,
FREETYPE_MINOR, and FREETYPE_PATCH cannot be used when the
library is dynamically linked by a program.
- Two new APIs have been added: `FT_Get_First_Char' and
`FT_Get_Next_Char'.
Together, these can be used to iterate efficiently over the
currently selected charmap of a given face. Read the API
reference for more details.
III. MISCELLANEOUS
- The FreeType sources are under heavy internal re-factoring. As
a consequence, we have created a branch named `STABLE' on the
CVS to hold all future releases/fixes in the 2.0.x family.
The HEAD branch now contains the re-factored sources and
shouldn't be used for testing or packaging new releases. In
case you would like to access the 2.0.9 sources from our CVS
repository, use the tag `VER-2-0-9'.
======================================================================
CHANGES BETWEEN 2.0.8 and 2.0.7
I. IMPORTANT BUG FIXES
- There was a small but nasty bug in `freetype-config.in' which
caused the `freetype-config' script to fail on Unix.
This didn't prevent the installation of the library or even its
execution, but caused problems when trying to compile many Unix
packages that depend on it.
- Some TrueType or OpenType fonts embedded in PDF documents do not
have a 'cmap', 'post' and 'name' as is required by the
specification. FreeType no longer refuses to load such fonts.
- Various fixes to the PCF font driver.
======================================================================
CHANGES BETWEEN 2.0.7 and 2.0.6
I. IMPORTANT BUG FIXES
- Fixed two bugs in the Type 1 font driver. The first one
resulted in a memory leak in subtle cases. The other one caused
FreeType to crash when trying to load `.gsf' files (Ghostscript
so-called Postscript fonts).
(This made _many_ KDE applications crash on certain systems.
FreeType _is_ becoming a critical system component on Linux :-)
- Fixed a memory leak in the CFF font driver.
- Fixed a memory leak in the PCF font driver.
- Fixed the Visual C++ project file
`builds/win32/visualc/freetype.dsp' since it didn't include the
Postscript hinter component, causing errors at build time.
- Fixed a small rendering bug in the anti-aliased renderer that
only occurred when trying to draw thin (less than 1 pixel)
strokes.
- Fixed `builds/unix/freetype2.a4' which is used to generate a
valid `freetype2.m4' for use with autoconf.
- Fixed the OpenVMS Makefiles.
II. MISCELLANEOUS
- Added `configure' and `install' scripts to the top-level
directory. A GNU-style installation is thus now easily possible
with
./configure <options>
make
make install
======================================================================
CHANGES BETWEEN 2.0.6 and 2.0.5
I. IMPORTANT BUG FIXES
- It wasn't possible to load embedded bitmaps when the auto-hinter
was used. This is now fixed.
- The TrueType font driver didn't load some composites properly
(the sub-glyphs were slightly shifted, and this was only
noticeable when using monochrome rendering).
- Various fixes to the auto-hinter. They merely improve the
output of sans-serif fonts. Note that there are still problems
with serifed fonts and composites (accented characters).
- All scalable font drivers erroneously returned un-fitted glyph
advances when hinting was requested. This created problems for
a number of layout applications. This is a very old bug that
got undetected mainly because most test/demo program perform
rounding explicitly or implicitly (through the cache).
- `FT_Glyph_To_Bitmap' did erroneously modify the source glyph in
certain cases.
- `glnames.py' still contained a bug that made FreeType return
invalid names for certain glyphs.
- The library crashed when loading certain Type 1 fonts like
`sadn.pfb' (`Stalingrad Normal'), which appear to contain
pathetic font info dictionaries.
- The TrueType glyph loader is now much more paranoid and checks
everything when loading a given glyph image. This was necessary
to avoid problems (crashes and/or memory overwrites) with broken
fonts that came from a really buggy automatic font converter.
II. IMPORTANT UPDATES AND NEW FEATURES
- Important updates to the Mac-specific parts of the library.
- The caching sub-system has been completely re-designed, and its
API has evolved (the old one is still supported for backward
compatibility).
The documentation for it is not yet completed, sorry. For now,
you are encouraged to continue using the old API. However, the
ftview demo program in the ft2demos package has already been
updated to use the new caching functions.
- A new charmap cache is provided too. See `FTC_CMapCache'. This
is useful to perform character code -> glyph index translations
quickly, without the need for an opened FT_Face.
- A NEW POSTSCRIPT HINTER module has been added to support native
hints in the following formats: PostScript Type 1, PostScript
CID, and CFF/CEF.
Please test! Note that the auto-hinter produces better results
for a number of badly-hinted fonts (mostly auto-generated ones)
though.
- A memory debugger is now part of the standard FreeType sources.
To enable it, define FT_DEBUG_MEMORY in
<freetype/config/ftoption.h>, and recompile the library.
Additionally, define the _environment_ variable FT_DEBUG_MEMORY
and run any program using FreeType. When the library is exited,
a summary of memory footprints and possible leaks will be
displayed.
This works transparently with _any_ program that uses FreeType.
However, you will need a lot of memory to use this (allocated
blocks are never released to the heap to detect double deletes
easily).
III. MISCELLANEOUS
- We are aware of subtle differences between the output of
FreeType versions 1 and 2 when it comes to monochrome
TrueType-hinted glyphs. These are most probably due to small
differences in the monochrome rasterizers and will be worked out
in an upcoming release.
- We have decided to fork the sources in a `stable' branch, and an
`unstable' one, since FreeType is becoming a critical component
of many Unix systems.
The next bug-fix releases of the library will be named 2.0.7,
2.0.8, etc., while the `2.1' branch will contain a version of
the sources where we will start major reworking of the library's
internals, in order to produce FreeType 2.2.0 (or even 3.0) in a
more distant future.
We also hope that this scheme will allow much more frequent
releases than in the past.
======================================================================
CHANGES BETWEEN 2.0.5 and 2.0.4
NOTE THAT 2.0.5 DOES NOT CONTAIN THE POSTSCRIPT HINTER. THIS MODULE
WILL BE PART OF THE NEXT RELEASE (EITHER 2.0.6 or 2.1)
- Fixed a bug that made certain glyphs, like `Cacute', `cacute' and
`lslash' unavailable from Unicode charmaps of Postscript fonts.
This prevented the correct display of Polish text, for example.
- The kerning table of Type 1 fonts was loaded by FreeType, when its
AFM file was attached to its face, but the
FT_FACE_FLAG_HAS_KERNING bit flags was not set correctly,
preventing FT_Get_Kerning to return meaningful values.
- Improved SFNT (TrueType & OpenType) charmap support. Slightly
better performance, as well as support for the new formats defined
by the OpenType 1.3 specification (8, 10, and 12)
- Fixed a serious typo in `src/base/ftcalc.c' which caused invalid
computations in certain rare cases, producing ugly artefacts.
- The size of the EM square is computed with a more accurate
algorithm for Postscript fonts. The old one caused slight errors
with embedded fonts found in PDF documents.
- Fixed a bug in the cache manager that prevented normal LRU
behaviour within the cache manager, causing unnecessary reloads
(for FT_Face and FT_Size objects only).
- Added a new function named `FT_Get_Name_Index' to retrieve the
glyph index of a given glyph name, when found in a face.
- Added a new function named `FT_Get_Postscript_Name' to retrieve
the `unique' Postscript font name of a given face.
- Added a new public header size named FT_SIZES_H (or
<freetype/ftsizes.h>) providing new FT_Size-management functions:
FT_New_Size, FT_Activate_Size, FT_Done_Size.
- Fixed a reallocation bug that generated a dangling pointer (and
possibly memory leaks) with Postscript fonts (in
src/psaux/psobjs.c).
- Many fixes for 16-bit correctness.
- Removed many pedantic compiler warnings from the sources.
- Added an Amiga build directory in `builds/amiga'.
======================================================================
CHANGES BETWEEN 2.0.4 and 2.0.3
- Fixed a rather annoying bug that was introduced in 2.0.3. Namely,
the font transformation set through FT_Set_Transform was applied
twice to auto-hinted glyphs, resulting in incorrectly rotated text
output.
- Fixed _many_ compiler warnings. FT2 should now compile cleanly
with Visual C++'s most pedantic warning level (/W4). It already
compiled fine with GCC and a few other compilers.
- Fixed a bug that prevented the linear advance width of composite
TrueType glyphs to be correctly returned.
- Fixed the Visual C++ project files located in
`builds/win32/visualc' (previous versions used older names of the
library).
- Many 32-bit constants have an `L' appended to their value, in
order to improve the 16-bitness of the code. Someone is actually
trying to use FT2 on an Atari ST machine!
- Updated the `builds/detect.mk' file in order to automatically
build FT2 on AIX systems. AIX uses `/usr/sbin/init' instead of
`/sbin/init' and wasn't previously detected as a Unix platform by
the FreeType build system.
- Updated the Unix-specific portions of the build system (new
libtool version, etc.).
- The SFNT kerning loader now ensures that the table is sorted
(since some problem fonts do not meet this requirement).
=======================================================================
CHANGES BETWEEN 2.0.3 and 2.0.2
I. CHANGES TO THE MODULES / FONT DRIVERS
- THE AUTO-HINTER HAS BEEN SLIGHTLY IMPROVED, in order to fix
several annoying artefacts, mainly:
- Blue zone alignment of horizontal stems wasn't performed
correctly, resulting in artefacts like the `d' being placed
one pixel below the `b' in some fonts like Time New Roman.
- Overshoot thresholding wasn't performed correctly, creating
unpleasant artefacts at large character pixel sizes.
- Composite glyph loading has been simplified. This gets rid
of various artefacts where the components of a composite
glyphs were not correctly spaced.
These are the last changes to the current auto-hinting module.
A new hinting sub-system is currently in the work in order to
support native hints in Type 1 / CFF / OpenType fonts, as well
as globally improve rendering.
- The PCF driver has been fixed. It reported invalid glyph
dimensions for the fonts available on Solaris.
- The Type 1, CID and CFF drivers have been modified to fix the
computation of the EM size.
- The Type 1 driver has been fixed to avoid a dangerous bug that
crashed the library with non-conforming fonts (i.e. ones that do
not place the .notdef glyph at position 0).
- The TrueType driver had a rather subtle bug (dangling pointer
when loading composite glyphs) that could crash the library in
rare occasions!
II. HIGH-LEVEL API CHANGES
- The error code enumeration values have been changed. An error
value is decomposed in a generic error code, and a module
number. see <freetype/fterrors.h> for details.
- A new public header file has been introduced, named
FT_TRIGONOMETRY_H (include/freetype/fttrigon.h), providing
trigonometric functions to compute sines, cosines, arctangents,
etc. with 16.16 fixed precision. The implementation is based on
the CORDIC algorithm and is very fast while being sufficiently
accurate.
III. INTERNALS
- Added BeOS-specific files in the old build sub-system. Note
that no changes were required to compile the library with Jam.
- The configuration is now capable of automatically detecting
64-bit integers on a set of predefined compilers (GCC, Visual
C++, Borland C++) and will use them by default. This provides a
small performance boost.
- A small memory leak that happened when opening 0-sized files
(duh!) have been fixed.
- Fixed bezier stack depth bug in the routines provided by the
FT_BBOX_H header file. Also fixed similar bugs in the
rasterizers.
- The outline bounding box code has been rewritten to use direct
computations, instead of bezier sub-division, to compute the
exact bounding box of glyphs. This is slightly slower but more
accurate.
- The build system has been improved and fixed, mainly to support
`make' on Windows 2000 correctly, avoid problems with `make
distclean' on non Unix systems, etc.
- Hexadecimal constants have been suffixed with `U' to avoid
problems with certain compilers on 64-bit platforms.
- A new directory named `src/tools' has been created. It contains
Python scripts and simple unit test programs used to develop the
library.
- The DocMaker tool has been moved from `docs' to `src/tools' and
has been updated with the following:
- Now accepts the `--title=XXXX' or `-t XXXX' option from the
command line to set the project's name in the generated API
reference.
- Now accepts the `--output=DIR' or `-o DIR' option from the
command line to set the output directory for all generated
HTML files.
- Now accepts the `--prefix=XXXX' or `-p XXX' option from the
command line to set the file prefix to use for all
generated HTML files.
- Now generates the current time/data on each generated page
in order to distinguish between versions.
DocMaker can be used with other projects now, not only FT2
(e.g. MLib, FTLayout, etc.).
======================================================================
CHANGES BETWEEN 2.0.2 and 2.0.1
I. CHANGES TO THE MODULES / FONT DRIVERS
- THE TRUETYPE BYTECODE INTERPRETER IS NOW TURNED OFF, in order to
avoid legal problems with the Apple patents. It seems that we
mistakenly turned this option on in previous releases of the
build.
Note that if you want to use the bytecode interpreter in order
to get high-quality TrueType rendering, you will need to toggle
by hand the definition of the
TT_CONFIG_OPTION_BYTECODE_INTERPRETER macro in the file
`include/freetype/config/ftoption.h'.
- The CFF driver has been improved by Tom Kacvinsky and Sander van
der Wal:
* Support for `seac' emulation.
* Support for `dotsection'.
* Support for retrieving glyph names through
`FT_Get_Glyph_Name'.
The first two items are necessary to correctly a large number of
Type 1 fonts converted to the CFF formats by Adobe Acrobat.
- The Type 1 driver was also improved by Tom & others:
* Better EM size computation.
* Better support for synthetic (transformed) fonts.
* The Type 1 driver returns the charstrings corresponding to
each glyph in the `glyph->control_data' field after a call to
`FT_Load_Glyph' (thanks Ha Shao).
- Various other bugfixes, including the following:
* Fixed a nasty memory leak in the Type 1 driver.
* The autohinter and the pcf driver used static writable data
when they shouldn't.
* Many casts were added to make the code more 64-bits safe. It
also now compiles on Windows XP 64-bits without warnings.
* Some incorrect writable statics were removed in the `autohint'
and `pcf' drivers. FreeType 2 now compiles on Epoc again.
II. CHANGES TO THE HIGH-LEVEL API
- The library header files inclusion scheme has been changed. The
old scheme looked like:
#include <freetype/freetype.h>
#include <freetype/ftglyph.h>
#include <freetype/ftcache.h>
#include <freetype/cache/ftimage.h>
Now you should use:
#include <ft2build.h>
#include FT_FREETYPE_H
#include FT_GLYPH_H
#include FT_CACHE_H
#include FT_CACHE_IMAGE_H
NOTE THAT THE OLD INCLUSION SCHEME WILL STILL WORK WITH THIS
RELEASE. HOWEVER, WE DO NOT GUARANTEE THAT THIS WILL STILL BE
TRUE IN THE NEXT ONE (A.K.A. FREETYPE 2.1).
The file <ft2build.h> is used to define the header filename
macros. The complete and commented list of macros is available
in the API reference under the section name `Header File Macros'
in Chapter I.
For more information, see section I of the following document:
http://www.freetype.org/
freetype2/docs/tutorial/step1.html
or
http://freetype.sourceforge.net/
freetype2/docs/tutorial/step1.html
- Many, many comments have been added to the public source file in
order to automatically generate the API Reference through the
`docmaker.py' Python script.
The latter has been updated to support the grouping of sections
in chapters and better index sort. See:
http://www.freetype.org/freetype2/docs/reference/ft2-toc.html
III. CHANGES TO THE BUILD PROCESS
- If you are not building FreeType 2 with its own build system
(but with your own Makefiles or project files), you will need to
be aware that the build process has changed a little bit.
You don't need to put the `src' directory in the include path
when compiling any FT2 component. Instead, simply put the
component's directory in the current include path.
So, if you were doing something like:
cc -c -Iinclude -Isrc src/base/ftbase.c
change the line to:
cc -c -Iinclude -Isrc/base src/base/ftbase.c
If you were doing something like:
cd src/base
cc -c -I../../include -I.. ftbase.c
change it to:
cd src/base
cc -c -I../../include ftbase.c
======================================================================
CHANGES BETWEEN 2.0.1 and 2.0
2.0.1 introduces a few changes:
- Fixed many bugs related to the support of CFF / OpenType fonts.
These formats are now much better supported though there is
still work planned to deal with charset tables and PDF-embedded
CFF files that use the old `seac' command.
- The library could not be compiled in debug mode with a very
small number of C compilers whose pre-processors didn't
implement the `##' directive correctly (i.e. per se the ANSI C
specification!) An elegant fix was found.
- Added support for the free Borland command-line C++ Builder
compiler. Use `make setup bcc32'. Also fixed a few source
lines that generated new warnings with BCC32.
- Fixed a bug in FT_Outline_Get_BBox when computing the extrema of
a conic Bezier arc.
- Updated the INSTALL file to add IDE compilation.
- Other minor bug fixes, from invalid Type 1 style flags to
correct support of synthetic (obliqued) fonts in the
auto-hinter, better support for embedded bitmaps in a SFNT font.
- Fixed some problems with `freetype-config'.
Finally, the `standard' scheme for including FreeType headers is now
gradually changing, but this will be explained in a later release
(probably 2.0.2).
And very special thanks to Tom Kacvinsky and YAMANO-UCHI Hidetoshi
for their contributions!
======================================================================
CHANGES BETWEEN beta8 and 2.0
- Changed the default installation path for public headers from
`include/freetype' to `include/freetype2'.
Also added a new `freetype-config' that is automatically generated
and installed on Unix and Cygwin systems. The script itself is
used to retrieve the current install path, C compilation flags as
well as linker flags.
- Fixed several small bugs:
* Incorrect max advance width for fixed-pitch Type 1 fonts.
* Incorrect glyph names for certain TrueType fonts.
* The glyph advance was not copied when FT_Glyph_To_Bitmap was
called.
* The linearHoriAdvance and linearVertAdvance fields were not
correctly returned for glyphs processed by the auto-hinter.
* `type1z' renamed back to `type1'; the old `type1' module has
been removed.
- Revamped the build system to make it a lot more generic. This
will allow us to re-use nearly un-modified in lots of other
projects (including FreeType Layout).
- Changed `cid' to use `psaux' too.
- Added the cache sub-system. See <freetype/ftcache.h> as well as
the sources in `src/cache'. Note that it compiles but is still
untested for now.
- Updated `docs/docmaker.py', a draft API reference is available at
http://www.freetype.org/ft2api.html.
- Changed `type1' to use `psaux'.
- Created a new module named `psaux' to hold the Type 1 & Type 2
parsing routines. It should be used by `type1', `cid', and `cff'
in the future.
- Fixed an important bug in `FT_Glyph_Get_CBox'.
- Fixed some compiler warnings that happened since the TrueType
bytecode decoder was deactivated by default.
- Fixed two memory leaks:
* The memory manager (16 bytes) isn't released in
FT_Done_FreeType!
* Using custom input streams, the copy of the original stream was
never released.
- Fixed the auto-hinter by performing automatic computation of the
`filling direction' of each glyph. This is done through a simple
and fast approximation, and seems to work (problems spotted by
Werner though). The Arphic fonts are a lot nicer though there are
still a lot of things to do to handle Asian fonts correctly.
======================================================================
BETA-8 (RELEASE CANDIDATE) CHANGES
- Deactivated the TrueType bytecode interpreter by default.
- Deactivated the `src/type1' font driver. Now `src/type1z' is used
by default.
- Updates to the build system. We now compile the library correctly
under Unix system through `configure' which is automatically
called on the first `make' invocation.
- Added the auto-hinting module! Fixing some bugs here and there.
- Found some bugs in the composite loader (seac) of the Type1-based
font drivers.
- Renamed the directory `freetype2/config' to `freetype2/builds' and
updated all relevant files.
- Found a memory leak in the `type1' driver.
- Incorporated Tom's patches to support flex operators correctly in
OpenType/CFF fonts. Now all I need is to support pure CFF and CEF
fonts to be done with this driver :-)
- Added the Windows FNT/FON driver in `src/winfonts'. For now, it
always `simulates' a Unicode charmap, so it shouldn't be
considered completed right now.
It is there to be more a proof of concept than anything else
anyway. The driver is a single C source file, that compiles to 3
Kb of code.
I'm still working on the PCF/BDF drivers, but I'm too lazy to
finish them now.
- CHANGES TO THE HIGH-LEVEL API
* FT_Get_Kerning has a new parameter that allows you to select the
coordinates of the kerning vector (font units, scaled, scaled +
grid-fitted).
* The outline functions are now in <freetype/ftoutln.h> and not
part of <freetype/freetype.h> anymore.
* <freetype/ftmodule.h> now contains declarations for
FT_New_Library, FT_Done_Library, FT_Add_Default_Modules.
* The so-called convenience functions have moved from `ftoutln.c'
to `ftglyph.c', and are thus available with this optional
component of the library. They are declared in
<freetype/ftglyph.h> now.
* Anti-aliased rendering is now the default for FT_Render_Glyph
(i.e. corresponds to render_mode == 0 == ft_render_mode_normal).
To generate a monochrome bitmap, use ft_render_mode_mono, or the
FT_LOAD_MONOCHROME flag in FT_Load_Glyph/FT_Load_Char.
FT_LOAD_ANTI_ALIAS is still defined, but values to 0.
* <freetype/freetype.h> now include <freetype/config/ftconfig.h>,
solving a few headaches :-)
* The type FT_GlyphSlotRec has now a `library' field.
- CHANGES TO THE `ftglyph.h' API
This API has been severely modified in order to make it simpler,
clearer, and more efficient. It certainly now looks like a real
`glyph factory' object, and allows client applications to manage
(i.e. transform, bbox and render) glyph images without ever
knowing their original format.
- Added support for CID-keyed fonts to the CFF driver. Maybe
support for pure CFF + CEF fonts should come in?
- Cleaned up source code in order to avoid two functions with the
same name. Also changed the names of the files in `type1z' from
`t1XXXX' to `z1XXXX' in order to avoid any conflicts.
`make multi' now works well :-)
Also removed the use of `cidafm' for now, even if the source files
are still there. This functionality will certainly go into a
specific module.
- ADDED SUPPORT FOR THE AUTO-HINTER
It works :-) I have a demo program which simply is a copy of
`ftview' that does a `FT_Add_Module(library,
&autohinter_module_class)' after library initialization, and Type
1 & OpenType/CFF fonts are now hinted.
CID fonts are not hinted, as they include no charmap and the
auto-hinter doesn't include `generic' global metrics computations
yet.
Now, I need to release this thing to the FreeType 2 source.
- CHANGES TO THE RENDERER MODULES
The monochrome and smooth renderers are now in two distinct
directories, namely `src/raster1' and `src/smooth'. Note that the
old `src/renderer' is now gone.
I ditched the 5-gray-levels renderers. Basically, it involved a
simple #define toggle in 'src/raster1/ftraster.c'.
FT_Render_Glyph, FT_Outline_Render & FT_Outline_Get_Bitmap now
select the best renderer available, depending on render mode. If
the current renderer for a given glyph image format isn't capable
of supporting the render mode, another one will be found in the
library's list. This means that client applications do not need
to switch or set the renderers themselves (as in the latest
change), they'll get what they want automatically. At last.
Changed the demo programs accordingly.
- MAJOR INTERNAL REDESIGN:
A lot of internal modifications have been performed lately on the
source in order to provide the following enhancements:
* More generic module support:
The FT_Module type is now defined to represent a handle to a
given module. The file <freetype/ftmodule.h> contains the
FT_Module_Class definition, as well as the module-loading public
API.
The FT_Driver type is still defined, and still represents a
pointer to a font driver. Note that FT_Add_Driver is replaced
by FT_Add_Module, FT_Get_Driver by FT_Get_Module, etc.
* Support for generic glyph image types:
The FT_Renderer type is a pointer to a module used to perform
various operations on glyph image.
Each renderer is capable of handling images in a single format
(e.g. ft_glyph_format_outline). Its functions are used to:
- transform an glyph image
- render a glyph image into a bitmap
- return the control box (dimensions) of a given glyph image
The scan converters `ftraster.c' and `ftgrays.c' have been moved
to the new directory `src/renderer', and are used to provide two
default renderer modules.
One corresponds to the `standard' scan-converter, the other to
the `smooth' one.
he current renderer can be set through the new function
FT_Set_Renderer.
The old raster-related function FT_Set_Raster, FT_Get_Raster and
FT_Set_Raster_Mode have now disappeared, in favor of the new:
FT_Get_Renderer
FT_Set_Renderer
See the file <freetype/ftrender.h> for more details.
These changes were necessary to properly support different
scalable formats in the future, like bi-color glyphs, etc.
* Glyph loader object:
A new internal object, called a 'glyph loader' has been
introduced in the base layer. It is used by all scalable format
font drivers to load glyphs and composites.
This object has been created to reduce the code size of each
driver, as each one of them basically re-implemented its
functionality.
See <freetype/internal/ftobjs.h> and the FT_GlyphLoader type for
more information.
* FT_GlyphSlot has new fields:
In order to support extended features (see below), the
FT_GlyphSlot structure has a few new fields:
linearHoriAdvance:
This field gives the linearly scaled (i.e. scaled but
unhinted) advance width for the glyph, expressed as a 16.16
fixed pixel value. This is useful to perform WYSIWYG text.
linearVertAdvance:
This field gives the linearly scaled advance height for the
glyph (relevant in vertical glyph layouts only). This is
useful to perform WYSIWYG text.
Note that the two above field replace the removed `metrics2'
field in the glyph slot.
advance:
This field is a vector that gives the transformed advance for
the glyph. By default, it corresponds to the advance width,
unless FT_LOAD_VERTICAL_LAYOUT was specified when calling
FT_Load_Glyph or FT_Load_Char.
bitmap_left:
This field gives the distance in integer pixels from the
current pen position to the left-most pixel of a glyph image
IF IT IS A BITMAP. It is only valid when the `format' field
is set to `ft_glyph_format_bitmap', for example, after calling
the new function FT_Render_Glyph.
bitmap_top:
This field gives the distance in integer pixels from the
current pen position (located on the baseline) to the top-most
pixel of the glyph image IF IT IS A BITMAP. Positive values
correspond to upwards Y.
loader:
This is a new private field for the glyph slot. Client
applications should not touch it.
* Support for transforms and direct rendering in FT_Load_Glyph:
Most of the functionality found in <freetype/ftglyph.h> has been
moved to the core library. Hence, the following:
- A transform can be specified for a face through
FT_Set_Transform. this transform is applied by FT_Load_Glyph
to scalable glyph images (i.e. NOT TO BITMAPS) before the
function returns, unless the bit flag FT_LOAD_IGNORE_TRANSFORM
was set in the load flags.
- Once a glyph image has been loaded, it can be directly
converted to a bitmap by using the new FT_Render_Glyph
function. Note that this function takes the glyph image from
the glyph slot, and converts it to a bitmap whose properties
are returned in `face.glyph.bitmap', `face.glyph.bitmap_left'
and `face.glyph.bitmap_top'. The original native image might
be lost after the conversion.
- When using the new bit flag FT_LOAD_RENDER, the FT_Load_Glyph
and FT_Load_Char functions will call FT_Render_Glyph
automatically when needed.
- Reformatted all modules source code in order to get rid of the
basic data types redifinitions (i.e. `TT_Int' instead of `FT_Int',
`T1_Fixed' instead of `FT_Fixed'). Hence the format-specific
prefixes like `TT_', `T1_', `T2_' and `CID_' are only used for
relevant structures.
======================================================================
OLD CHANGES FOR BETA 7
- bug-fixed the OpenType/CFF parser. It now loads and displays my
two fonts nicely, but I'm pretty certain that more testing is
needed :-)
- fixed the crummy Type 1 hinter, it now handles accented characters
correctly (well, the accent is not always well placed, but that's
another problem..)
- added the CID-keyed Type 1 driver in `src/cid'. Works pretty well
for only 13 Kb of code ;-) Doesn't read AFM files though, nor the
really useful CMAP files..
- fixed two bugs in the smooth renderer (src/base/ftgrays.c).
Thanks to Boris Letocha for spotting them and providing a fix.
- fixed potential `divide by zero' bugs in ftcalc.c.
- added source code for the OpenType/CFF driver (still incomplete
though..)
- modified the SFNT driver slightly to perform more robust header
checks in TT_Load_SFNT_Header. This prevents certain font files
(e.g. some Type 1 Multiple Masters) from being incorrectly
`recognized' as TrueType font files..
- moved a lot of stuff from the TrueType driver to the SFNT module,
this allows greater code re-use between font drivers
(e.g. TrueType, OpenType, Compact-TrueType, etc..)
- added a tiny segment cache to the SFNT Charmap 4 decoder, in order
to minimally speed it up..
- added support for Multiple Master fonts in `type1z'. There is
also a new file named <freetype/ftmm.h> which defines functions to
manage them from client applications.
The new file `src/base/ftmm.c' is also optional to the engine..
- various formatting changes (e.g. EXPORT_DEF -> FT_EXPORT_DEF) +
small bug fixes in FT_Load_Glyph, the `type1' driver, etc..
- a minor fix to the Type 1 driver to let them apply the font matrix
correctly (used for many oblique fonts..)
- some fixes for 64-bit systems (mainly changing some FT_TRACE calls
to use %p instead of %lx). Thanks to Karl Robillard.
- fixed some bugs in the sbit loader (src/base/sfnt/ttsbit.c) +
added a new flag, FT_LOAD_CROP_BITMAP to query that bitmaps be
cropped when loaded from a file (maybe I should move the bitmap
cropper to the base layer ??).
- changed the default number of gray levels of the smooth renderer
to 256 (instead of the previous 128). Of course, the human eye
can't see any difference ;-)
- removed TT_MAX_SUBGLYPHS, there is no static limit on the number
of subglyphs in a TrueType font now..
======================================================================
OLD CHANGES 16 May 2000
- tagged `BETA-6' in the CVS tree. This one is a serious release
candidate even though it doesn't incorporate the auto-hinter yet..
- various obsolete files were removed, and copyright header updated
- finally updated the standard raster to fix the monochrome
rendering bug + re-enable support for 5-gray levels anti-aliasing
(suck, suck..)
- created new header files, and modified sources accordingly:
<freetype/fttypes.h>
- simple FreeType types, without the API
<freetype/internal/ftmemory.h>
- definition of memory-management macros
- added the `DSIG' (OpenType Digital Signature) tag to
<freetype/tttags.h>
- light update/cleaning of the build system + changes to the sources
in order to get rid of _all_ compiler warnings with three
compilers, i.e:
gcc with `-ansi -pedantic -Wall -W', Visual C++ with `/W3 /WX' and
LCC
IMPORTANT NOTE FOR WIN32-LCC USERS:
|
| It seems the C pre-processor that comes with LCC is broken, it
| doesn't recognize the ANSI standard directives # and ##
| correctly when one of the argument is a macro. Also,
| something like:
|
| #define F(x) print##x
|
| F(("hello"))
|
| will get incorrectly translated to:
|
| print "hello")
|
| by its pre-processor. For this reason, you simply cannot build
| FreeType 2 in debug mode with this compiler..
- yet another massive grunt work. I've changed the definition of
the EXPORT_DEF, EXPORT_FUNC, BASE_DEF & BASE_FUNC macros. These
now take an argument, which is the function's return value type.
This is necessary to compile FreeType as a DLL on Windows and
OS/2. Depending on the compiler used, a compiler-specific keyword
like __export or __system must be placed before (VisualC++) or
after (BorlandC++) the type..
Of course, this needed a lot of changes throughout the source code
to make it compile again... All cleaned up now, apparently..
Note also that there is a new EXPORT_VAR macro defined to allow
the _declaration_ of an exportable public (constant)
variable. This is the case of the raster interfaces (see
ftraster.h and ftgrays.h), as well as each module's interface (see
sfdriver.h, psdriver.h, etc..)
- new feature: it is now possible to pass extra parameters to font
drivers when creating a new face object. For now,
this capability is unused. It could however prove to
be useful in a near future..
the FT_Open_Args structure was changes, as well as the internal
driver interface (the specific `init_face' module function has
now a different signature).
- updated the tutorial (not finished though).
- updated the top-level BUILD document
- fixed a potential memory leak that could occur when loading
embedded bitmaps.
- added the declaration of FT_New_Memory_Face in
<freetype/freetype.h>, as it was missing from the public header
(the implementation was already in `ftobjs.c').
- the file <freetype/fterrors.h> has been seriously updated in order
to allow the automatic generation of error message tables. See
the comments within it for more information.
- major directory hierarchy re-organisation. This was done for two
things:
* first, to ease the `manual' compilation of the library by
requiring at lot less include paths :-)
* second, to allow external programs to effectively access
internal data fields. For example, this can be extremely
useful if someone wants to write a font producer or a font
manager on top of FreeType.
Basically, you should now use the 'freetype/' prefix for header
inclusion, as in:
#include <freetype/freetype.h>
#include <freetype/ftglyph.h>
Some new include sub-directories are available:
a. the `freetype/config' directory, contains two files used to
configure the build of the library. Client applications
should not need to look at these normally, but they can if
they want.
#include <freetype/config/ftoption.h>
#include <freetype/config/ftconfig.h>
b. the `freetype/internal' directory, contains header files that
describes library internals. These are the header files that
were previously found in the `src/base' and `src/shared'
directories.
As usual, the build system and the demos have been updated to
reflect the change..
Here's a layout of the new directory hierarchy:
TOP_DIR
include/
freetype/
freetype.h
...
config/
ftoption.h
ftconfig.h
ftmodule.h
internal/
ftobjs.h
ftstream.h
ftcalc.h
...
src/
base/
...
sfnt/
psnames/
truetype/
type1/
type1z/
Compiling a module is now much easier, for example, the following
should work when in the TOP_DIR directory on an ANSI build:
gcc -c -I./include -I./src/base src/base/ftbase.c
gcc -c -I./include -I./src/sfnt src/sfnt/sfnt.c
etc..
(of course, using -Iconfig/<system> if you provide system-specific
configuration files).
- updated the structure of FT_Outline_Funcs in order to allow direct
coordinate scaling within the outline decomposition routine (this
is important for virtual `on' points with TrueType outlines) +
updates to the rasters to support this..
- updated the OS/2 table loading code in `src/sfnt/ttload.c' in
order to support version 2 of the table (see OpenType 1.2 spec)
- created `include/tttables.h' and `include/t1tables.h' to allow
client applications to access some of the SFNT and T1 tables of a
face with a procedural interface (see `FT_Get_Sfnt_Table') +
updates to internal source files to reflect the change..
- some cleanups in the source code to get rid of warnings when
compiling with the `-Wall -W -ansi -pedantic' options in gcc.
- debugged and moved the smooth renderer to `src/base/ftgrays.c' and
its header to `include/ftgrays.h'
- updated TT_MAX_SUBGLYPHS to 96 as some CJK fonts have composites
with up to 80 sub-glyphs !! Thanks to Werner
======================================================================
OLD CHANGES - 14-apr-2000
- fixed a bug in the TrueType glyph loader that prevented the
correct loading of some CJK glyphs in mingli.ttf
- improved the standard Type 1 hinter in `src/type1'
- fixed two bugs in the experimental Type 1 driver in `src/type1z'
to handle the new XFree86 4.0 fonts (and a few other ones..)
- the smooth renderer is now complete and supports sub-banding to
render large glyphs at high speed. However, it is still located
in `demos/src/ftgrays.c' and should move to the library itself in
the next beta. NOTE: The smooth renderer doesn't compile in
stand-alone mode anymore, but this should be fixed RSN..
- introduced convenience functions to more easily deal with glyph
images, see `include/ftglyph.h' for more details, as well as the
new demo program named `demos/src/ftstring.c' that demonstrates
its use
- implemented FT_LOAD_NO_RECURSE in both the TrueType and Type 1
drivers (this is required by the auto-hinter to improve its
results).
- changed the raster interface, in order to allow client
applications to provide their own span-drawing callbacks.
However, only the smooth renderer supports this. See
`FT_Raster_Params' in the file `include/ftimage.h'.
- fixed a small bug in FT_MulFix that caused incorrect transform
computation!
- Note: The tutorial is out-of-date.
======================================================================
OLD CHANGES - 12-mar-2000
- changed the layout of configuration files : now, all ANSI
configuration files are located in
`freetype2/config'. System-specific over-rides can be placed in
`freetype2/config/<system>'.
- moved all configuration macros to `config/ftoption.h'
- improvements in the Type 1 driver with AFM support
- changed the fields in the FT_Outline structure : the old `flags'
array is re-named `tags', while all ancient flags are encoded into
a single unsigned int named `flags'.
- introduced new flags in FT_Outline.flags (see
ft_outline_.... enums in `ftimage.h').
- changed outline functions to `FT_Outline_<action>' syntax
- added a smooth anti-alias renderer to the demonstration programs
- added Mac graphics driver (thanks Just)
- FT_Open_Face changed in order to received a pointer to a
FT_Open_Args descriptor..
- various cleanups, a few more API functions implemented (see
FT_Attach_File)
- updated some docs
======================================================================
OLD CHANGES - 22-feb-2000
- introduced the `psnames' module. It is used to:
o convert a Postscript glyph name into the equivalent Unicode
character code (used by the Type 1 driver(s) to synthesize on
the fly a Unicode charmap).
o provide an interface to retrieve the Postscript names of the
Macintosh, Adobe Standard & Adobe Expert character codes.
(the Macintosh names are used by the SFNT-module postscript
names support routines, while the other two tables are used by
the Type 1 driver(s)).
- introduced the `type1z' alternate Type 1 driver. This is a (still
experimental) driver for the Type 1 format that will ultimately
replace the one in `src/type1'. It uses pattern matching to load
data from the font, instead of a finite state analyzer. It works
much better than the `old' driver with `broken' fonts. It is also
much smaller (under 15 Kb).
- the Type 1 drivers (both in `src/type1' and `src/type1z') are
nearly complete. They both provide automatic Unicode charmap
synthesis through the `psnames' module. No re-encoding vector is
needed. (note that they still leak memory due to some code
missing, and I'm getting lazy).
Trivial AFM support has been added to read kerning information but
wasn't exactly tested as it should ;-)
- The TrueType glyph loader has been seriously rewritten (see the
file `src/truetype/ttgload.c'. It is now much, much simpler as
well as easier to read, maintain and understand :-) Preliminary
versions introduced a memory leak that has been reported by Jack
Davis, and is now fixed..
- introduced the new `ft_glyph_format_plotter', used to represent
stroked outlines like Windows `Vector' fonts, and certain Type 1
fonts like `Hershey'. The corresponding raster will be written
soon.
- FT_New_Memory_Face is gone. Likewise, FT_Open_Face has a new
interface that uses a structure to describe the input stream, the
driver (if required), etc..
TODO
- Write FT_Get_Glyph_Bitmap and FT_Load_Glyph_Bitmap
- Add a function like FT_Load_Character(face, char_code, load_flags)
that would really embed a call to FT_Get_Char_Index then
FT_Load_Glyph to ease developer's work.
- Update the tutorial!
- consider adding support for Multiple Master fonts in the Type 1
drivers.
- Test the AFM routines of the Type 1 drivers to check that kerning
information is returned correctly.
- write a decent auto-gridding component !! We need this to release
FreeType 2.0 gold !
less urgent needs:
- add a CFF/Type2 driver
- add a BDF driver
- add a FNT/PCF/HBF driver
- add a Speedo driver from the X11 sources
======================================================================
OLDER CHANGES - 27-jan-2000
- updated the `sfnt' module interface to allow several SFNT-based
drivers to co-exist peacefully
- updated the `T1_Face' type to better separate Postscript font
content from the rest of the FT_Face structure. Might be used
later by the CFF/Type2 driver..
- added an experimental replacement Type 1 driver featuring advanced
(and speedy) pattern matching to retrieve the data from postscript
fonts.
- very minor changes in the implementation of FT_Set_Char_Size and
FT_Set_Pixel_Sizes (they now implement default to lighten the font
driver's code).
======================================================================
OLD MESSAGE
This file summarizes the changes that occurred since the last `beta'
of FreeType 2. Because the list is important, it has been divided into
separate sections:
Table Of Contents:
I High-Level Interface (easier !)
II Directory Structure
III Glyph Image Formats
IV Build System
V Portability
VI Font Drivers
----------------------------------------------------------------------
High-Level Interface:
The high-level API has been considerably simplified. Here is how:
- resource objects have disappeared. this means that face objects
can now be created with a single function call (see FT_New_Face
and FT_Open_Face)
- when calling either FT_New_Face & FT_Open_Face, a size object
and a glyph slot object are automatically created for the face,
and can be accessed through `face->glyph' and `face->size' if
one really needs to. In most cases, there's no need to call
FT_New_Size or FT_New_Glyph.
- similarly, FT_Load_Glyph now only takes a `face' argument
(instead of a glyph slot and a size). Also, its `result'
parameter is gone, as the glyph image type is returned in the
field `face->glyph.format'
- the list of available charmaps is directly accessible through
`face->charmaps', counting `face->num_charmaps' elements. Each
charmap has an 'encoding' field which specifies which known
encoding it deals with. Valid values are, for example:
ft_encoding_unicode (for ASCII, Latin-1 and Unicode)
ft_encoding_apple_roman
ft_encoding_sjis
ft_encoding_adobe_standard
ft_encoding_adobe_expert
other values may be added in the future. Each charmap still
holds its `platform_id' and `encoding_id' values in case the
encoding is too exotic for the current library
----------------------------------------------------------------------
Directory Structure:
Should seem obvious to most of you:
freetype/
config/ -- configuration sub-makefiles
ansi/
unix/ -- platform-specific configuration files
win32/
os2/
msdos/
include/ -- public header files, those to be included
directly by client apps
src/ -- sources of the library
base/ -- the base layer
sfnt/ -- the sfnt `driver' (see the drivers section
below)
truetype/ -- the truetype driver
type1/ -- the type1 driver
shared/ -- some header files shared between drivers
demos/ -- demos/tools
docs/ -- documentation (a bit empty for now)
----------------------------------------------------------------------
Glyph Image Formats:
Drivers are now able to register new glyph image formats within the
library. For now, the base layer supports of course bitmaps and
vector outlines, but one could imagine something different like
colored bitmaps, bi-color vectors or whatever else (Metafonts anyone
??).
See the file `include/ftimage.h'. Note also that the type
FT_Raster_Map is gone, and is now replaced by FT_Bitmap, which
should encompass all known bitmap types.
Each new image format must provide at least one `raster', i.e. a
module capable of transforming the glyph image into a bitmap. It's
also possible to change the default raster used for a given glyph
image format.
The default outline scan-converter now uses 128 levels of grays by
default, which tends to smooth many things. Note that the demo
programs have been updated significantly in order to display these..
----------------------------------------------------------------------
Build system:
You still need GNU Make to build the library. The build system has
been very seriously re-vamped in order to provide things like :
- automatic host platform detection (reverting to 'config/ansi' if
it is not detected, with pseudo-standard compilation flags)
- the ability to compile from the Makefiles with very different and
exotic compilers. Note that linking the library can be difficult
for some platforms.
For example, the file `config/win32/lcclib.bat' is invoked by the
build system to create the `.lib' file with LCC-Win32 because its
librarian has too many flaws to be invoked directly from the
Makefile.
Here's how it works:
- the first time you type `make', the build system runs a series of
sub-makefiles in order to detect your host platform. It then
dumps what it found, and creates a file called `config.mk' in the
current directory. This is a sub-Makefile used to define many
important Make variables used to build the library.
- the second time, the build system detects the `config.mk' then use
it to build the library. All object files go into 'obj' by
default, as well as the library file, but this can easily be
changed.
Note that you can run `make setup' to force another host platform
detection even if a `config.mk' is present in the current
directory. Another solution is simply to delete the file, then
re-run make.
Finally, the default compiler for all platforms is gcc (for now,
this will hopefully changed in the future). You can however specify
a different compiler by specifying it after the 'setup' target as
in:
gnumake setup lcc on Win32 to use the LCC compiler
gnumake setup visualc on Win32 to use Visual C++
See the file `config/<system>/detect.mk' for a list of supported
compilers for your platforms.
It should be relatively easy to write new detection rules files and
config.mk..
Finally, to build the demo programs, go to `demos' and launch GNU
Make, it will use the `config.mk' in the top directory to build the
test programs..
----------------------------------------------------------------------
Portability:
In the previous beta, a single FT_System object was used to
encompass all low-level operations like thread synchronisation,
memory management and i/o access. This has been greatly simplified:
- thread synchronisation has been dropped, for the simple reason
that the library is already re-entrant, and that if you really
need two threads accessing the same FT_Library, you should
really synchronize access to it yourself with a simple mutex.
- memory management is performed through a very simple object
called `FT_Memory', which really is a table containing a table
of pointers to functions like malloc, realloc and free as well
as some user data (closure).
- resources have disappeared (they created more problems than they
solved), and i/o management have been simplified greatly as a
result. Streams are defined through FT_Stream objects, which
can be either memory-based or disk-based.
Note that each face has its own stream, which is closed only
when the face object is destroyed. Hence, a function like
TT_Flush_Face in 1.x cannot be directly supported. However, if
you really need something like this, you can easily tailor your
own streams to achieve the same feature at a lower level (and
use FT_Open_Face instead of FT_New_Face to create the face).
See the file `include/ftsystem.h' for more details, as well as the
implementations found in `config/unix' and `config/ansi'.
----------------------------------------------------------------------
Font Drivers:
The Font Driver interface has been modified in order to support
extensions & versioning.
The list of the font drivers that are statically linked to the
library at compile time is managed through a new configuration file
called `config/<platform>/ftmodule.h'.
This file is autogenerated when invoking `make modules'. This
target will parse all sub-directories of 'src', looking for a
`module.mk' rules file, used to describe the driver to the build
system.
Hence, one should call `make modules' each time a font driver is
added or removed from the `src' directory.
Finally, this version provides a `pseudo-driver' in `src/sfnt'.
This driver doesn't support font files directly, but provides
services used by all TrueType-like font drivers. Hence, its code is
shared between the TrueType & OpenType font formats, and possibly
more formats to come if we're lucky..
----------------------------------------------------------------------
Extensions support:
The extensions support is inspired by the one found in 1.x.
Now, each font driver has its own `extension registry', which lists
which extensions are available for the font faces managed by the
driver.
Extension ids are now strings, rather than 4-byte tags, as this is
usually more readable.
Each extension has:
- some data, associated to each face object
- an interface (table of function pointers)
An extension that is format-specific should simply register itself
to the correct font driver. Here is some example code:
// Registering an extensions
//
FT_Error FT_Init_XXXX_Extension( FT_Library library )
{
FT_DriverInterface* tt_driver;
driver = FT_Get_Driver( library, "truetype" );
if (!driver) return FT_Err_Unimplemented_Feature;
return FT_Register_Extension( driver, &extension_class );
}
// Implementing the extensions
//
FT_Error FT_Proceed_Extension_XXX( FT_Face face )
{
FT_XXX_Extension ext;
FT_XXX_Extension_Interface ext_interface;
ext = FT_Get_Extension( face, "extensionid", &ext_interface );
if (!ext) return error;
return ext_interface->do_it(ext);
}
------------------------------------------------------------------------
Copyright 2000-2013 by
David Turner, Robert Wilhelm, and Werner Lemberg.
This file is part of the FreeType project, and may only be used,
modified, and distributed under the terms of the FreeType project
license, LICENSE.TXT. By continuing to use, modify, or distribute this
file you indicate that you have read the license and understand and
accept it fully.
Local Variables:
version-control: never
coding: utf-8
End:
--- end of CHANGES ---