The calculation of `vertBearingX' is not defined in the OTF font
spec so FreeType does a `best effort' attempt. However, this value
is defined in the PDF and PostScript specs, and that algorithm is
better than the one FreeType currently uses:
FreeType: Use the middle of the bounding box as the X coordinate
of the vertical origin.
Adobe PDF spec: Use the middle of the horizontal advance vector as
the X coordinate of the vertical origin.
FreeType's algorithm goes wrong if you have a really small glyph
(like the full-width, circle-like dot at the end of the sentence, as
used in CJK scripts) with large bearings. With the FreeType
algorithm this dot gets centered on the baseline; with the PDF
algorithm it gets the correct location (in the top right). Note
that this is a serious issue, it's like printing the dot at the end
of a Roman sentence at the center of the textline instead of on the
baseline like it should. So i believe the PDF spec's algorithm
should be used in FreeType as well.
The `vertBearingY' value for such small glyphs is also very strange
if no `vmtx' information is present, since the height of the bbox is
not representable for the height of the glyph visually (the
whitespace up to the baseline is part of the glyph). The fix also
includes some code for a better estimate of `vertBearingY'.
* src/base/ftobjs.c (ft_synthesize_vertical_metrics): `vertBearingX'
is now calculated as described by the Adobe PDF Spec. Estimate for
`vertBearingY' now works better for small glyphs completely above or
below the baseline into account.
* src/cff/cffgload.c (cff_slot_load): `vertBearingX' is now
calculated as described by the Adobe PDF Spec. Vertical metrics
information was always ignored when FT_CONFIG_OPTION_OLD_INTERNALS
was not defined.
* src/truetype/ttgload.c (compute_glyph_metrics): `vertBearingX' is
now calculated as described by the Adobe PDF Spec.
* src/base/ftobjs.c (FT_Load_Glyph): Alter check for permitted
matrices to allow rotations by multiples of 90°, not only unrotated,
possibly slanted matrices.
* include/freetype/config/ftoption.h add FT_CONFIG_OPTION_PIC
* include/freetype/internal/ftobjs.h Add pic_container member to
FT_LibraryRec.
Add macros to declare and init instances of FT_CMap_ClassRec.
Add macros to init instances of FT_Outline_Funcs and FT_Raster_Funcs.
Add macros to declare, allocate and initialize modules
(FT_Module_Class).
Add macros to declare, allocate and initialize renderers
(FT_Renderer_Class).
Add macro to init instances of FT_Glyph_Class.
Add macros to declare, allocate and initialize drivers
(FT_Driver_ClassRec).
* include/freetype/internal/ftpic.h new file to declare the
FT_PIC_Container struct and the functions to allocate and detroy it.
* include/freetype/internal/ftserv.h add macros to allocate and
destory arrays of FT_ServiceDescRec.
* include/freetype/internal/internal.h define macro to include
ftpic.h.
New Files:
* src/base/ftpic.c implement functions to allocate and destory the
global pic_container.
* src/base/basepic.h declare struct to hold PIC globals for base and
macros to access them.
* src/base/basepic.c implement functions to allocate, destroy and
initialize PIC globals for base.
* src/base/ftinit.c when FT_CONFIG_OPTION_PIC is defined implement
functions that allocate and destroy ft_default_modules according to
FT_CONFIG_MODULES_H in the pic_container instead of the global scope
and use macro from basepic.h to access it.
* src/base/ftobjs.c add calls to the functions that allocate and
destroy the global pic_container when the library is created and
destroyed.
* src/base/jamfile add new files to FT2_MULTI build:
ftpic.c and basepic.c.
* src/base/ftbase.c add new files to build:
ftpic.c and basepic.c.
* src/base/ftglyph.c when FT_CONFIG_OPTION_PIC is defined
ft_bitmap_glyph_class and ft_outline_glyph_class will be allocated
in the pic_container instead of the global scope and use macros from
basepic.h to access them.
* src/base/ftbbox.c allocate bbox_interface stract on the stack
instead of the global scope when FT_CONFIG_OPTION_PIC is defined.
* src/base/ftstroke.c access ft_outline_glyph_class allocated in
ftglyph.c via macros from basepic.h
src/smooth/ftgrays.c, src/base/ftobjc.s, src/sfobjs.c:
s/_Err_Bad_Argument/_Err_Invalid_Argument/. The former is for
errors in the bytecode interpreter only.
FT_FACE_FLAG_TRICKY to indicate that the font format's hinting
engine is necessary for correct rendering.
At the same time, slightly modify the behaviour of tricky fonts:
FT_LOAD_NO_HINTING is now ignored. To really force raw loading
of tricky fonts (without hinting), both FT_LOAD_NO_HINTING and
FT_LOAD_NO_AUTOHINT must be used.
Finally, tricky TrueType fonts always use the bytecode interpreter
even if the patented code is used.
* include/freetype/freetype.h (FT_FACE_FLAG_TRICKY, FT_IS_TRICKY):
New macros.
* src/truetype/ttdriver.c (Load_Glyph): Handle new load flags
semantics as described above.
* src/truetype/ttobjs.c (tt_check_trickyness): New function, using
code of ...
(tt_face_init): This function, now simplified and updated to new
semantics.
* src/base/ftobjs.c (FT_Load_Glyph): Don't use autohinter for tricky
fonts.
* docs/CHANGES: Document it.
nor bitmaps can be considered as containing space `glyphs' only.
* src/truetype/ttpload.c (tt_face_load_loca): Handle the case where
a `glyf' table is missing.
* src/truetype/ttgload.c (load_truetype_glyph): Abort if we have no
`glyf' table but a non-zero `loca' entry.
(tt_loader_init): Handle missing `glyf' table.
* src/base/ftobjs.c (FT_Load_Glyph): Undo change 2008-12-05.
* src/sfnt/sfobjs.c (sfnt_load_face): A font with neither outlines
nor bitmaps is scalable.
0x100 instead of 0x10000; the latter value is already occupied by
FT_LOAD_TARGET_LIGHT. Bug reported by James Cloos.
Handle SFNT with neither outlines nor bitmaps. This fixes Savannah
bug #25010.
* src/base/ftobjs.c (FT_Load_Glyph): Reject fonts with neither
outlines nor bitmaps.
* src/sfnt/sfobjs.c (sfnt_load_face): Don't return an error if there
is no table with glyphs.
* src/sfnt/ttload.c (tt_face_lookup_table): Improve debugging
message.
Other minor cosmetics.
(FT_Outline_Decompose): Decorate with tracing messages.
* src/smooth/ftgrays.c [DEBUG_GRAYS]: Replace with
FT_DEBUG_LEVEL_TRACE.
[_STANDALONE_ && FT_DEBUG_LEVEL_TRACE]: Include stdio.h and
stdarg.h.
(FT_TRACE) [_STANDALONE_]: Remove.
(FT_Message) [_STANDALONE_ && FT_DEBUG_LEVEL_TRACE]: New function.
(FT_TRACE5, FT_TRACE7) [_STANDALONE_]: New macros.
(FT_ERROR) [_STANDALONE_]: Updated.
(gray_hline) [FT_DEBUG_LEVEL_TRACE]: Fix condition.
Use FT_TRACE7.
(gray_dump_cells): Make it `static void'.
(graay_convert_glyph): Use FT_TRACE7.
(FT_Outline_Decompose) [_STANDALONE_]: Synchronize with version in
ftoutln.c.
* src/base/ftadvanc.c (FT_Get_Advance, FT_Get_Advances): Use
FT_ERROR_BASE.
Other minor modifications.
targets).
* src/base/ftobjs.c (FT_Open_Face): Don't define a variable in block
which is crossed by a `goto'.
* src/otvalid/otvalid.h (otv_MATH_validate): Add prototype.
cmap14-related new APIs to the FT_Object_ActionName scheme.
update the documentation for these APIs
* src/sfnt/ttcmap.c: stronger cmap 14 validation, make the
code a little more consistent with FreeType coding conventions
and modify the cmap14 functions that returned a newly allocated
array to use a persistent vector from the TT_CMap14 object
instead.
Bram Tassyns