This is the large, famous `Infinality' patch to support ClearType
bytecode which has been available from
http://www.infinality.net/blog/ for some time, and which has been
refined over the last years. While still experimental, it is now
mature enough to be included directly into FreeType.
Most of the code is based on the ClearType whitepaper written by
Greg Hitchcock
http://www.microsoft.com/typography/cleartype/truetypecleartype.aspx
which gives a detailed overview of the necessary changes to the
Microsoft rasterizer so that older fonts are supported. However, a
lot of details are still missing, and this patches provides a
framework to easily handle rendering issues down to the glyph level
of certain fonts.
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.
* src/truetype/ttsubpix.c: New file, providing code to handle
`tweaks', this is, rules for certain glyphs in certain fonts
(including wildcards) which need a special treatment.
* src/truetype/ttsubpix.h: New file, holding the tweaking rules.
* include/freetype/config/ftoption.h, src/devel/ftoption.h
(TT_CONFIG_OPTION_SUBPIXEL_HINTING): New macro.
* include/freetype/internal/ftobjs.h (FT_PIX_FLOOR_GRID,
FT_PIX_ROUND_GRID, FT_PIX_CEIL_GRID): New macros.
* src/truetype/truetype.c [TT_USE_BYTECODE_INTERPRETER]: Include
`ttsubpix.c'.
* src/truetype/ttgload.c: Include `ttsubpix.h'.
[All changes below are guarded by TT_CONFIG_OPTION_SUBPIXEL_HINTING.]
(tt_get_metrics): Set tweak flags.
(TT_Hint_Glyph): Call `FT_Outline_EmboldenXY' if necessary.
(TT_Process_Simple_Glyph): Compensate emboldening if necessary.
(compute_glyph_metrics): Handle `compatible widths' option.
(tt_loader_init): Handle ClearType GETINFO information bits.
* src/truetype/rules.mk (TT_DRC_SRC): Updated.
* src/truetype/ttinterp.c: Include `ttsubpix.h'.
[Where necessary, changes below are guarded by
TT_CONFIG_OPTION_SUBPIXEL_HINTING.]
(Direct_Move, Direct_Move_X): Extended.
(Round_None, Round_To_Grid, Round_To_Half_Grid, Round_Down_To_Grid,
Round_Up_To_Grid, Round_To_Double_Grid, Round_Super, Round_Super_45,
SetSuperRound): Add parameter to handle the number of grid lines per
pixel.
(SET_SuperRound, ROUND_None, CUR_Func_round): Updated.
(DO_SROUND, DOS45ROUND, DO_ODD, DO_EVEN): Updated.
(DO_ROUND, DO_NROUND): Updated.
(DO_RS): Take care of `Typeman' bytecode patterns.
(Ins_FDEF): Add some debugging code. Commented out.
(Ins_ENDF): Restore state.
(Ins_CALL, Ins_LOOPCALL): Handle inline delta functions.
(Ins_MD): Handle `Vacuform' rounds.
(Move_Zp2_Point, Ins_SHPIX, Ins_MSIRP, Ins_MDAP, Ins_MIAP,
Ins_MDRP, Ins_MIRP): Handle tweaks.
(Ins_ALIGNRP): Add tweak guard.
(Ins_IUP, Ins_DELTAP): Handle tweaks.
(Ins_GETINFO): Handle new ClearType bits.
(TT_RunIns): Handle tweaks.
* src/truetype/ttinterp.h: Updated.
(SPH_TweakRule, SPH_ScaleRule): New structures for tweaks.
(TT_ExecContextRec): Add members for subpixel hinting support.
* src/truetype/ttobjs.h (TT_DefRecord): Add `inline_delta' member.
* src/truetype/ttinterp.c (DO_SSW): SSW *does* use font units. For
verification, it took some time to find a font which actually uses
this instruction.
* src/truetype/ttinterp.c (Ins_MIRP): Typo, present since ages. The
code is now in sync with the other operators (e.g. MSIRP) which
modify twilight points.
Jump instructions are now bound to the current function. The MS
Windows rasterizer behaves the same, as confirmed by Greg Hitchcock.
* src/truetype/ttinterp.h (TT_CallRec): Add `Cur_End' element.
* src/truetype/ttobjs.h (TT_DefRecord): Add `end' element.
* src/truetype/ttinterp.c (DO_JROT, DO_JMPR, DO_JROF): Check upper
bound of jump address.
(Ins_FDEF, Ins_CALL, Ins_LOOPCALL, Ins_UNKNOWN, TT_RunIns): Updated.
* src/truetype/interp.c: Set even more TT_Err_Invalid_Reference
error codes only if pedantic hinting is active. At the same time,
try to provide sane values which hopefully allow useful
continuation. Exception to this is CALL and LOOPCALL – due to
possible stack corruption it is necessary to bail out.
* src/truetype/ttinterp.c (TT_RunIns, Ins_FLIPPT, Ins_DELTAP,
Ins_DELTAC): Exit with error only if `pedantic_hinting' is set.
Otherwise, try to do something sane.
Thanks to Greg Hitchcock who explained the issue.
* src/truetype/ttinterp.c (Ins_MIRP): Replace a `>=' operator with
`>' since the description in the specification is incorrect.
This fixes, for example, glyph `two' in font `Helvetica Neue LT Com
65 medium' at 15ppem.
On LLP64 platforms (e.g. Win64), long (32-bit) cannot cover
the memory address (64-bit). Also the casts from the pointer
type to long int should be removed to preserve the address
correctly.
* src/raster/ftraster.c (New_Profile): Replace "%lx" by "%p".
(End_Profile) Ditto.
* src/truetype/ttinterp.c (Init_Context): Ditto.
* src/truetype/ttinterp.c (free_buffer_in_size): Don't duplicate
FT_GlyphZoneRec size->twilight to be freed. If duplicated,
FT_FREE() erases the duplicated pointers only and leave original
pointers. They can cause the double-free crash when the burst
errors occur in TrueType interpreter and free_buffer_in_size()
is invoked repeatedly. See Savannah bug #31040 for detail.
* src/truetype/ttinterp.c (TT_RunIns): Decrease the trace level
showing the error when the interpreter returns with an error,
from FT_TRACE7() to FT_TRACE1().
* src/truetype/ttinterp.c (free_buffer_in_size): New function to
free the buffer allocated during the interpretation of this glyph.
(TT_RunIns): Unset FT_Face->size->{cvt_ready,bytecode_ready} if
an error occurs in the bytecode interpretation. The interpretation
of invalid bytecode may break the function definitions and referring
them in later interpretation is danger. By unsetting these flags,
`fpgm' and `prep' tables are executed again in next interpretation.
Fix Savannah bug #30798, reported by Robert Swiecki.
* src/truetype/ttinterp.c (BOUNDSL): New macro.
Change `BOUNDS' to `BOUNDSL' where appropriate.
* src/truetype/ttinterp.h (TT_ExecContextRec): Fix type of
`cvtSize'.
Acroread does the same.
* src/truetype/ttgload.c (TT_Process_Composite_Glyph): Call
`Update_Max' to adjust size of instructions array if necessary and
add a rough safety check.
(load_truetype_glyph): Save `loader->byte_len' before recursive
call.
* src/truetype/ttinterp.h, src/truetype/ttinterp.c (Update_Max):
Declare it as FT_LOCAL.
* src/raster/ftraster.c (Render_Glyph, Render_Gray_Glyph,
Draw_Sweep): No-dropout mode is value 2, not value 0.
(Draw_Sweep): Really skip dropout handling for no-dropout mode.
Pass dropout rules from the TT bytecode interpreter to the
rasterizer; temporarily this is enabled only if
`USE_SCAN_CONVERSION_RULES' is defined.
* include/freetype/ftimage.h (FT_OUTLINE_SMART_DROPOUTS,
FT_OUTLINE_EXCLUDE_STUBS): New flags for for FT_Outline.
* src/raster/ftraster.c (Vertical_Sweep_Drop, Horizontal_Sweep_Drop,
Horizontal_Gray_Sweep_Drop): Use same mode numbers as given in the
OpenType specification.
Fix mode 4 computation.
(Render_Glyph, Render_Gray_Glyph): Handle new outline flags.
* src/truetype/ttgload.c (TT_Load_Glyph)
[USE_SCAN_CONVERSION_RULES]: Convert scan conversion mode to
FT_OUTLINE_XXX flags.
* src/truetype/ttinterp.c (Ins_SCANCTRL): Enable ppem check.
bitmap embolderner when the pitch of the source bitmap is
*much* larger than its width
* src/truetype/ttinterp.c: fixing aliasing-related compilation
warning
include/freetype/internal/tttypes.h, src/base/ftgloadr.c,
src/base/ftobjs.c, src/truetype/ttgload.c, src/truetype/ttinterp.c,
src/truetype/ttobjs.c: improvements to native TrueType hinting,
this is a first try, controlled by the FIX_BYTECODE macro in
src/truetype/ttinterp.c
unused `max_points' and `max_contours'.
* src/cid/cidobjs.c (cid_face_init), src/type1/t1objs.c
(T1_Face_Init), src/type42/t42objs.c (T42_Face_Init): Update.
* include/freetype/internal/tttypes.h (TT_FaceRec): Remove unused
`max_components'.
* src/truetype/ttinterp.h (TT_ExecContextRec): Remove unused
`loadSize' and `loadStack'.
* src/truetype/ttinterp.c (TT_Done_Context, TT_Load_Context),
src/sfnt/ttload.c (tt_face_load_maxp): Update.
* src/cff/cffobjs.h (cff_size_select), src/sfnt/sfdriver.c
(sfnt_interface), src/truetype/ttdriver.c (tt_size_request): Fix
compiler errors/warnings when TT_CONFIG_OPTION_EMBEDDED_BITMAPS is not
defined.
* src/sfnt/ttmtx.c (tt_face_load_hmtx, tt_face_get_metrics): Fix
possible segment faults for the non-FT_OPTIMIZE_MEMORY'ed versions.
(finally!)
For most OpenType tables, `tt_face_load_xxxx' simply loads the table
and `face->root' is set later in `sfnt_load_face'. Here, we try to
make this work for _all_ tables.
* src/sfnt/ttsbit.c, src/sfnt/ttsbit0.c, src/sfnt/ttload.c,
src/sfnt/ttmtx.c: all `tt_face_load_xxxx' should load the table and
then exit. Error handling or setting face->root is done later in
`sfnt_load_face'.
Pretty trace messages.
* src/sfnt/sfobjs.c (sfnt_load_face): Work harder.
Mac bitmap-only fonts are not scalable.
Check that `face->header.Units_Per_EM' is not zero.
(LOAD_, LOADM_): Pretty trace messages.
* src/sfnt/ttsbit0.c (tt_face_load_strike_metrics): Read metrics from
`eblc'.
* src/sfnt/ttcmap.c (tt_face_build_cmaps), src/sfnt/ttpost.c
(load_format_20, load_format_25, tt_face_get_ps_name): Use
face->max_profile.numGlyphs, instead of face->root.num_glyphs.
invalid computations, resulting in very weird bugs in TrueType
bytecode hinted fonts
* src/truetype/ttinterp.c: redefined FT_UNUSED_EXEC to not perform
a structure copy each time. Wooot. !
TT_Done_Context and rename TT_Destroy_Context to TT_Done_Context with
slight changes.
* src/truetype/ttobjs.h (tt_slot_init): New function.
* src/truetype/ttobjs.c (tt_driver_init): Initialize execution context
here.
(tt_slot_init): New function to create extra points for the internal
glyph loader. We then use it directly, instead of face's glyph loader,
when loading glyph.
* src/truetype/ttdriver.c: Use tt_slot_init for glyph slot
initialization.
(TT_Load_Glyph): Load flag dependencies are handled here.
Return error if size is NULL.
* src/truetype/ttgload.c: Heavy cleanup and refactor.
(TT_Hint_Glyph): New funcion to hint a zone, prepared by caller.
(TT_Process_Simple_Glyph): Use loader->pp's instead of recalculating.
Use TT_Hint_Glyph.
No need to save/restore loader->stream before/after
TT_Vary_Get_Glyph_Deltas now.
(TT_LOADER_SET_PP): New macro to calculate and set the four phantom points.
(TT_Process_Composite_Component, TT_Process_Composite_Glyph,
load_truetype_glyph): Refactor load_truetype_glyph into these three functions.
Never set exec->glyphSize to 0. (close#13107)
Forget glyph frame before calling TT_Process_Simple_Glyph.
(TT_Load_Glyph, load_sbit_image, tt_loader_init): Refactor TT_Load_Glyph into
these three functions.
Set various fields of `glyph' here, instead of in load_truetype_glyph
and compute_glyph_metrics.
Fix handling of NPUSHW if skipped in data stream.
* src/truetype/ttinterp.c (opcode_length): Set value for NPUSHW
to -2.
(SkipCode, TT_RunIns): Use opcode_length value for computation of
bytes to be skipped.
bytecode interpreter. This is an experimental feature which
should probably be made optional.
* src/truetype/ttgload.c (TT_Process_Simple_Glyph,
load_truetype_glyph): Move the code to set the pedantic_hinting flag
to...
(TT_Load_Glyph): Here.
Set `grayscale' flag except for `FT_LOAD_TARGET_MONO'.
* src/truetyep/ttinterp.c (Ins_GETINFO): Return MS rasterizer
version 1.7.
Return rotation and stretching info only if glyph is rotated or
stretched, respectively.
Handle grayscale info.
* src/truetype/ttinterp.h (TT_ExecContextRec): Add `grayscale'
member.
fixed a dangling pointer bug that happened in very rare cases:
i.e. when a new family object was destroyed by an out-of-memory
condition during a glyph node initialization. The function
FTC_Cache_Lookup would flush the cache and restart the lookup
with a bad pointer.
* src/cache/ftcmanag.c: fixed a cache flushing bug
FTC_FaceID.
* src/cff/cffdrivr.c (cff_get_cmap_info): Call sfnt module's TT CMap
Info service function if the cmap comes from sfnt. Return 0 if the
cmap is sythesized in cff module.
Formatting; updating copyright.
src/autohint/ahhint.c, src/base/ftgloadr.c,
src/base/ftglyph.c, src/base/ftoutln.c,
src/base/ftstroke.c, src/cff/cffload.c, src/truetype/ttgload.c,
src/truetype/ttinterp.c:
introducing the new FT_ARRAY_COPY and FT_ARRAY_MOVE macros
to make copying arrays easier
64 bit version).
* include/freetype/internal/ftcalc.h: Updated.
* src/truetype/ttinterp.c (TT_MULDIV_NO_ROUND): New macro.
(TT_INT64): Removed.
(DO_DIV): Use TT_MULDIV_NO_ROUND.
* src/pfr/pfrdrivr.c (pfr_get_metrics): Directly use
metrics->x_scale and metrics->y_scale.
(Direct_Move_Orig, Direct_Move_Orig_X, Direct_Move_Orig_Y): New
functions. Similar to Direct_Move, Direct_Move_X, and
Direct_Move_Y but without touching.
(Compute_Funcs): Use new functions.
(Round_None, Round_To_Grid, Round_To_Half_Grid, Round_Down_To_Grid,
Round_Up_To_Grid, Round_To_Double_Grid, Round_Super,
Round_Super_45): Fix rounding of value zero.
(DO_DIV): Don't use TT_MULDIV.
(Ins_SHC): This instruction actually touches the points.
(Ins_MSIRP): Fix undocumented behaviour.
* src/truetype/ttinterp.h (TT_ExecContextRec): Updated.
* docs/VERSION.DLL: Updated.
* src/base/ftobjs.c (FT_Set_Char_Size): Make metrics->x_scale and
metrics->y_scale really precise.
(FT_Load_Glyph): Update computation of linearHoriAdvance and
linearVertAdvance.
* src/true/type/ttinterp.c (Update_Max): Use FT_REALLOC.
include/freetype/internal/ftobjs.h, include/freetype/internal/tttypes.h,
src/truetype/ttinterp.c, src/truetype/ttobjs.c, src/truetype/ttobjs.h:
changed the name of TT_CONFIG_OPTION_COMPILE_UNPATENTED_HINTING to
the simpler TT_CONFIG_OPTION_UNPATENTED_HINTING
removed the macro TT_CONFIG_OPTION_FORCE_UNPATENTED_HINTING. Instead,
the same effect can be used by setting a debug-hook with
FT_DEBUG_HOOK_UNPATENTED_HINTING globally with FT_Set_Debug_Hook()
want to list them all here. The operations performed were all logical
transformations of the sources:
- trying to convert all enums and constants to CAPITALIZED_STYLE, with
#define definitions like
#define my_old_constants MY_NEW_CONSTANT
- big, big update of the documentation comments
* include/freetype/freetype.h, src/base/ftobjs.c, src/smooth/ftsmooth.c,
include/freetype/ftimage.h: adding support for LCD-optimized rendering
though the new constants/enums:
FT_RENDER_MODE_LCD, FT_RENDER_MODE_LCD_V
FT_PIXEL_MODE_LCD, FT_PIXEL_MODE_LCD_V
this is still work in progress, don't expect everything to work correctly
though most of the features have been implemented.
* adding new FT_LOAD_XXX flags, used to specify both hinting and rendering
targets:
FT_LOAD_TARGET_NORMAL :: anti-aliased hinting & rendering
FT_LOAD_TARGET_MONO :: monochrome bitmaps
FT_LOAD_TARGET_LCD :: horizontal RGB/BGR decimated hinting & rendering
FT_LOAD_TARGET_LCD_V :: vertical RGB/BGR decimated hinting & rendering
note that FT_LOAD_TARGET_NORMAL is 0, which means that the default
behaviour of the font engine is _unchanged_.
FT_LOCAL and FT_LOCAL_DEF, respectively, as with other ftconfig.h
files.
* builds/unix/ftconfig.in: Add argument to FT_LOCAL and
FT_LOCAL_DEF.
* src/truetype/ttinterp.c: s/FT_Assert/FT_ASSERT/.
* builds/unix/configure.ac: Temporarily deactivate creation of
../../Jamfile.
* builds/unix/configure: Updated.
changed the names of memory macros. Examples:
MEM_Set => FT_MEM_SET
MEM_Copy => FT_MEM_COPY
MEM_Move => FT_MEM_MOVE
ALLOC => FT_ALLOC
FREE => FT_FREE
REALLOC = >FT_REALLOC
FT_NEW was introduced to allocate a new object from a _typed_
pointer..
note that ALLOC_ARRAY and REALLOC_ARRAY have been replaced
by FT_NEW_ARRAY and FT_RENEW_ARRAY which take _typed_ pointer
arguments.
This results in _lots_ of sources being changed, but makes the
code more generic and less error-prone..
use the new trigonometric functions provided in "fttrigon.h". This
gets rid of some old 64-bit computation routines, as well as many
warnings when compiling the library with the "long long" 64-bit
integer type.
Fixed a bug that returned an invalid linear width for composite
TrueType glyphs.
* include/internal/tttypes.h (TT_Loader_): Two new elements `linear'
and `linear_def'.
* src/truetype/ttgload.c (load_truetype_glyph,
compute_glyph_metrics): Use it.
* include/fttypes.h (FT_ERROR_BASE): New macro.
* src/base/ftobjs.c (FT_Open_Face, FT_Render_Glyph_Internal): Use it
to make source code work with the new error scheme implemented by
Werner.
* src/base/ftoutln.c (FT_Outline_Render): Ditto.
details.
* include/freetype/internal/cfferrs.h,
include/freetype/internal/tterrors.h,
include/freetype/internal/t1errors.h: Removed. Replaced with files
local to the module. All extra error codes have been moved to
`fterrors.h'.
* src/sfnt/ttpost.h: Move error codes to `fterrors.h'.
* src/autohint/aherrors.h, src/cache/ftcerror.h, src/cff/cfferrs.h,
src/cid/ciderrs.h, src/pcf/pcferror.h, src/psaux/psauxerr.h,
src/psnames/psnamerr.h, src/raster/rasterrs.h, src/sfnt/sferrors.h,
src/smooth/ftsmerrs.h, src/truetype/tterrors.h,
src/type1/t1errors.h, src/winfonts/fnterrs.h: New files defining the
error names for the module it belongs to.
* include/freetype/ftmoderr.h: New file, defining the module error
offsets. Its structure is similar to `fterrors.h'.
* include/freetype/fterrors.h (FT_NOERRORDEF): New macro.
(FT_ERRORDEF): Redefined to use module error offsets.
All internal error codes are now public; unused error codes have
been removed, some are new.
* include/freetype/config/ftheader.h (FT_MODULE_ERRORS_H): New
macro.
* include/freetype/config/ftoption.h
(FT_CONFIG_OPTION_USE_MODULE_ERRORS): New macro.
All other source files have been updated to use the new error codes;
some already existing (internal) error codes local to a module have
been renamed to give them the same name as in the base module.
All make files have been updated to include the local error files.
* src/cid/cidtokens.h: Replaced with...
* src/cid/cidtoken.h: This file for 8+3 consistency.
* src/raster/ftraster.c: Use macros for header file names.
* include/freetype/config/ftheader.h: removed obsolete macros like
FT_SOURCE_FILE, etc.. and added cache-specific macro definitions that
were previously defined in <freetype/ftcache.h>. Added comments to be
included in a new API Reference section.
* src/*/*: removed the use of FT_SOURCE_FILE, etc.. now, each component
needs to added its own directory to the include path at compile time.
Modified all "rules.mk" and "descrip.mms" accordingly..
to use direct definitions. This is the only way to do these things
in a portable way :-( The rest of the code should follow shortly
though everything compiles now.
* builds/compiler/intelc.mk, builds/compiler/watcom.mk: New files.
* builds/win32/detect.mk: Added support for the Intel C/C++
compiler, as well as _preliminary_ (read: doesn't work!) support for
Watcom. Also added a new setup target. Type "make setup list" for
a list of supported command-line compilers on Win32.
* src/base/ftdebug.c: Added dummy symbol to avoid empty file if
conditionals are off.
include/freetype/internal/internal.h: fixed header inclusion macros
to use direct definitions. This is the only way to do these things
in a portable way :-( The rest of the code should follow shortly
though everything compiles now..
* builds/compiler/intelc.mk, builds/compiler/watcom.mk,
builds/win32/detect.mk: added support for the Intel C/C++ compiler,
as well as _preliminary_ (read: doesn't work !!) support for Watcom.
Also added a new setup target. Type "make setup list" for a list
of supported command-line compilers on Win32..
Removed. ANSI C doesn't (explicitly) allow macro expansion in
arguments using `##'.
(FT2_PUBLIC_FILE, FT2_CONFIG_FILE, FT2_INTERNAL_FILE): Use directory
names directly. Make them configurable. Use `##' to strip leading
and trailing spaces from arguments.
* builds/unix/ft2unix.h: Adapted.
* src/base/ftsystem.c (ft_alloc, ft_realloc, ft_free, ft_io_stream,
ft_close_stream): Use FT_CALLBACK_DEF.
* builds/unix/ftsystem.c: Use new header scheme.
(FT_Done_Memory): Use free() from FT_Memory structure.
* src/base/ftinit.c, src/base/ftmac.c: Header scheme fixes.
* include/freetype/config/ft2build.h (FT2_CONFIG_ROOT,
FT2_PUBLIC_FILE, FT2_CONFIG_FILE, FT2_INTERNAL_FILE,
FT_SOURCE_FILE): Use `##' operator to be really ANSI C compliant.
in the "builds" directory
- modified a few files because BCC32 didn't like certain comparisons
(UInt compared with a UShort, apparently the UShort is promoted to
an Int)
- updated the INSTALL file to include IDE compilation, prevent against
BSD Make, and clarify the use of "make setup" (instead of "make")
for build configuration
C++ programs easier:
Renamed FT_WordXX to FT_UIntXX.
Changed a lot of void* to FT_Byte* if related to i/o streams -- FreeType
always accesses streams byte-wise, so this makes sense IMHO.
Added a lot of #ifdef __cplusplus to header files (and removed a few).
Other minor syntax fixes (mostly casts).
Replaced the variable `private' with `private_dict' -- `private' is
reserved in C++.
- using FT_UNUSED instead of UNUSED
- using FT_LONG64 and FT_INT64 instead of LONG64 & INT64
- using FT_SIZEOF_INT & FT_SIZEOF_LONG instead of...
- removed the #ifdefs that used SIZEOF_INT, instead we now
use FT_Int32 and FT_UInt32 when needed to support
32-bits quantity correctly on 64-bits systems..
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.
The 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 had 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 WHEN 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 WHEN 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.
rid of most of the basic types redefinitions (i.e. FT_Int instead
of "FT_Int", etc..)
The format-specific prefixs like "TT_", "T1_", "T2_" & 'CID_"
are now only used in relevant structures..
fixed Werner's fix to t2gload.c :-)
other small bug fixes
compiler warnings with GCC + "-ansi -pedantic -Wall -W"
and LCC.
Also fixed the compilation of "type1z" with Win32-LCC
(its pre-processor is broken !!)
Updated the BUILD document too
EXPORT_FUNC, BASE_DEF and BASE_FUNC macros to
let them take an argument..
This is needed to compile the library as a DLL on some platforms
that have different compiler conventions..
- modified the interface of the "sfnt" module. There is now a function
called "load_format_tag", and another called "load_directory".
The first one is in charge of returning the 4-byte tag located at
the beginning of a given font file. It understand TrueType collections
and parses them automatically
The second loads the table directory that is located just after
the format tag.
This is useful, because the "SFNT" storage scheme can be used by
several distinct formats, each with its own format tag.
The TrueType driver now checks the format tag in "src/truetype/ttobjs.c"
- made some changes to "src/shared/t1types.h" to clearly separate the
Type 1 font content from the rest of the T1_Face structure. This
will be useful when adding the CFF/Type2 driver that will be able
to reuse the "T1_Font" structure within a "TT_Font" one (which
really describes a SFNT-based font file).
Some changes in "src/type1" were thus performed to reflect this.
Note that the current type1 driver will be discontinued in a
distant future. More on this later..
Infinality