* src/truetype/ttgload.c (TT_Load_Simple_Glyph): Check instruction
size only if we do native hinting.
(TT_Load_Glyph): Trace returned error code.
* src/truetype/ttobjs.c (tt_size_run_fpgm, tt_size_run_prep): Trace
returned error code.
(tt_size_ready_bytecode): Don't run `prep' table if `fpgm' table is
invalid.
* src/cff/cffdrivr.c: Don't include
`FT_SERVICE_METRICS_VARIATIONS_H'.
(cff_get_advances): Use `ttface->variation_support'.
* src/truetype/ttdriver.c (tt_get_advances): Use
`ttface->variation_support'.
* src/truetype/ttgload.c (TT_Process_Simple_Glyph,
load_truetype_glyph): Use `ttface->variation_support'.
When asking for an unhinted non-default variations,
`linearVertAdvance' is currently the value from the `hmtx' table
instead of the actual value after applying the variation. `HVAR'
support fixes this, but fonts will exist without that table and will
need sane fallback.
* src/truetype/ttgload.c (TT_Process_Simple_Glyph,
load_truetype_glyph): Implement linear advance adjustments if `HVAR'
or `VVAR' tables are missing.
* include/freetype/internal/tttypes.h (TT_Face): Move
`is_default_instance' into TT_CONFIG_OPTION_GX_VAR_SUPPORT
block.
* src/sfnt/sfobjs.c (sfnt_init_face): Updated.
* src/truetype/ttgload.c (IS_DEFAULT_INSTANCE): New macro.
(TT_Load_Glyph): Use it.
This avoids additional calls to `tt_face_lookup_table' for the
`glyf' table, which can be expensive.
* include/freetype/internal/tttypes.h (TT_LoaderRec): Move
`glyf_offset' field to ...
(TT_FaceRec): ... this structure.
* src/truetype/ttgload.c (load_truetype_glyph): Updated.
(tt_loader_init): Move initialization of `glyf_offset' to ...
* src/truetype/ttpload.c (tt_face_load_loca): .. this function.
Since 2016-05-16 we detect infinite recursion directly.
* src/sfnt/ttload.c (tt_face_load_maxp): Don't adjust
`maxComponentDepth'.
* src/truetype/ttgload.c (load_truetype_glyph): Don't abort if
`maxComponentDepth' is not valid. Instead, simply adjust its value
and emit a tracing message.
This patch prepares data structures and the like.
See added comments in `ttinterp.h' for more information on this and
the following commits in the series.
* devel/ftoption.h, include/freetype/config/ftoption.h
(TT_CONFIG_OPTION_SUBPIXEL_HINTING): Assign values to differentiate
between subpixel versions.
(TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY,
TT_SUPPORT_SUBPIXEL_HINTING_MINIMAL): New macros.
* include/freetype/ftttdrv.h (TT_INTERPRETER_VERSION_40): New macro.
* include/freetype/internal/tttypes.h (TT_FaceRec): Updated.
* src/truetype/ttinterp.h (TT_ExecContextRec): Define new fields
`subpixel_hinting_lean', `vertical_lcd_lean',
`backwards_compatibility', `iupx_called', iupy_called', and
`grayscale_cleartype' for new hinting mode.
* src/truetype/ttdriver.c (tt_property_set): Handle v38 and v40
interpreters conditionally.
* src/truetype/ttgload.c (TT_Hint_Glyph): Save phantom points unless
in v38 backwards compatibility mode.
Updated.
(compute_glyph_metrics): Add v38 backwards compatibility mode
constraint for adjusting advance widths.
Updated.
(tt_loader_init): Handle new flags `subpixel_hinting_lean',
`grayscale_cleartype', and `vertical_lcd_lean'.
Updated.
(tt_get_metrics, TT_Process_Simple_Glyph, TT_LOADER_SET_PP):
Updated.
* src/truetype/ttobjs.c (tt_driver_init): Conditionally set
default interpreter version number.
* src/truetype/ttsubpix.c, src/truetype/ttsubpix.h: Updated.
The previous fix for #46372 misunderstood a composite glyph referring
same component twice as a recursive reference. See the discussion
http://lists.gnu.org/archive/html/freetype/2016-05/msg00000.html
Thanks to Khaled Hosny for finding this issue.
* src/truetype/ttgload.c (ft_list_get_node_at): A function to get
the i-th node from FT_List. (load_truetype_glyph): In the traversal
scan of the reference tree in the composite glyph, we clear the
nodes filled by previous sibling chain.
* include/freetype/internal/tttypes.h (TT_LoaderRec): New field
`composites'.
* src/truetype/ttgload.c: Include FT_LIST_H.
(load_truetype_glyph): Add composite subglyph index to a list;
abort if index is already in list.
(tt_loader_init): Updated.
(tt_loader_done): New function.
(TT_Load_Glyph): Call `tt_loader_done'.
* src/base/ftrfork.c (FT_Raccess_Get_HeaderInfo): Only accept
positive values from header.
Check overflow.
* src/base/ftoutln.c (SCALED): Correctly handle left-shift of
negative values.
* src/bdf/bdf.h (_bdf_glyph_modified, _bdf_set_glyph_modified,
_bdf_clear_glyph_modified): Use unsigned long constant.
* src/bdf/bdfdrivr.c (BDF_Size_Select, BDF_Glyph_Load): Don't
left-shift values that can be negative.
* src/pcf/pcfdrivr.c (PCF_Size_Select, PCF_Glyph_Load): Don't
left-shift values that can be negative.
* src/raster/ftraster.c (SCALED): Correctly handle left-shift of
negative values.
* src/sfnt/ttsbit.c (tt_face_load_strike_metrics): Don't left-shift
values that can be negative.
* src/truetype/ttgload.c (TT_Load_Composite_Glyph,
compute_glyph_metrics, load_sbit_image): Don't left-shift values
that can be negative.
This is completely missing in Apple's documentation: If a `gvar'
tuple uses private point numbers (this is, deltas are specified for
some points only), the uncovered points must be interpolated for
this tuple similar to the IUP bytecode instruction. Examples that
need this functionality are glyphs `Oslash' and `Q' in Skia.ttf.
* src/truetype/ttgxvar.c (tt_delta_shift, tt_delta_interpolate,
tt_handle_deltas): New functions.
(TT_Vary_Get_Glyph_Deltas): Renamed to...
(TT_Vary_Apply_Glyph_Deltas): ... this; it directly processes the
points and does no longer return an array of deltas.
Add tracing information.
Call `tt_handle_deltas' to interpolate missing deltas.
Also fix a minor memory leak in case of error.
* src/truetype/ttgxvar.h: Updated.
* src/truetype/ttgload.c (TT_Process_Simple_Glyph,
load_truetype_glyph): Updated.
* src/truetype/ttgload.c, src/truetype/ttinterp.c: Guard new code
with `TT_CONFIG_OPTION_SUBPIXEL_HINTING'.
Problem reported by Nikolaus Waxweiler <madigens@gmail.com>.
This flag activates `native ClearType hinting', disabling backwards
compatibility mode as described in Greg Hitchcocks whitepaper. In
other words, it enables unrestricted functionality of all TrueType
instructions in ClearType.
* src/truetype/ttgload.c (tt_get_metrics): Call `sph_set_tweaks'
unconditionally.
(tt_loader_init): Unset `ignore_x_mode' flag if bit 2 of
`GS.instruct_control' is active.
* src/truetype/ttinterp.c (Ins_INSTCTRL): Handle selector index 3.
(Ins_GETINFO): Updated.
* docs/CHANGES: Document it.
* src/truetype/ttgload.c (TT_Load_Composite_Glyph): If the
ARGS_ARE_XY_VALUES flag is not set, handle argument values as
unsigned. I trust `ttx' (which has exactly such code) that it does
the right thing here...
The reason that noone has ever noticed this bug is probably the fact
that point-aligned subglyphs are rare, as are subglyphs with a
number of points in the range [128;255], which is quite large (or
even in the range [32768;65535], which is extremely unlikely).
* src/truetype/ttgload.c (load_truetype_glyph): For incremental
fonts, the glyph index may be greater than the number of glyphs
indicated, so guard the check with a preprocessor conditional.
Previously the code had stipulation for using a per-TT_Size exec
context if `size->debug' was true. But there was no way that
`size->debug' could *ever* be true. As such, the code was always
using the singleton `TT_ExecContext' that was stored in `TT_Driver'.
This was, clearly, not threadsafe.
With this patch, loading glyphs from different faces from different
threads doesn't crash in the bytecode loader code.
* src/truetype/ttobjs.h (TT_SizeRec): Remove `debug' member.
(TT_DriverRec): Remove `context' member.
* src/truetype/ttobjs.c (tt_size_run_fpgm, tt_size_run_prep): Remove
`TT_ExecContext' code related to a global `TT_Driver' object.
(tt_driver_done): Don't remove `TT_ExecContext' object here but ...
(tt_size_done_bytecode): ... here.
(tt_driver_init): Don't create `TT_ExecContext' object here but ...
(tt_size_init_bytecode): ... here, only on demand.
* src/truetype/ttinterp.c (TT_Run_Context): Remove defunct debug
code.
(TT_New_Context): Remove `TT_ExecContext' code related to a global
`TT_Driver' object.
* src/truetype/ttinterp.h: Updated.
* src/truetype/ttgload.c (TT_Hint_Glyph, tt_loader_init): Updated.
The functions in this patch *do* return non-trivial errors that must
be taken care of.
* src/autofit/afloader.c (af_loader_load_g), src/base/ftobjs.c
(FT_Render_Glyph_Internal), src/base/ftoutln.c (FT_Outline_Render),
src/cff/cffgload.c (cff_decoder_parse_charstrings) <cff_op_endchar>,
src/psaux/psobjs.c (ps_parser_load_field_table), src/psaux/t1decode
(t1_decoder_parse_charstrings) <op_endchar>, src/truetype/ttgload.c
(load_truetype_glyph <subglyph loop>, tt_loader_init,
TT_Load_Glyph), src/truetype/ttgxvar.c (TT_Set_MM_Blend),
src/truetype/ttobjs.c (tt_size_run_fpgm, tt_size_run_prep): Do it.
Suggested by Doug Felt <dougfelt@gmail.com>.
* src/sfnt/ttsbit.c (tt_sbit_decoder_load_metrics): Set
`vertAdvance' to zero...
* src/truetype/ttgload.c (TT_Load_Glyph): ... and set here a default
value for `vertAdvance' based on `linearVertAdvance' in case
`vertAdvance' is zero. Note that the previous computed ad-hoc value
for `linearVertAdvance' was apparently not tested in a real-life
situation.
In case of an error in the `prep' table, no longer try to execute it
again and again. This makes FreeType handle endless loops in buggy
fonts much faster.
* src/truetype/ttobjs.h (TT_SizeRec): The fields `bytecode_ready'
and `cvt_ready' are now negative if not initialized yet, otherwise
they indicate the error code of the last run.
* src/truetype/ttobjs.c (tt_size_run_fpgm, tt_size_run_prep,
tt_size_done_bytecode, tt_size_init_bytecode,
tt_size_ready_bytecode, tt_size_init, tt_size_done, tt_size_reset):
Updated.
* src/truetype/ttgload.c (tt_loader_init): Updated.
* src/truetype/ttinterp.c (TT_RunIns): Force reexecution of `fpgm'
and `prep' only if we are in the `glyf' table.
Werner Lemberg