* src/base/ftobjs.c (open_face_PS_from_sfnt_stream,
Mac_Read_sfnt_Resource): Do not zero out the buffer.
* src/base/ftmac.c (FT_New_Face_From_SFNT, read_lwfn): Ditto.
* src/base/ftrfork.c (raccess_make_file_name,
raccess_guess_darwin_hfsplus, raccess_guess_darwin_newvfs): Ditto.
* src/sfnt/ttcolr.c (tt_face_get_paint_layers): Do not output
layer pointer to iterator if it is outside the 'COLR' table.
(read_paint): Do not attempt to read layers that are outside the
table.
* src/base/ftobjs.c (ft_glyphslot_clear): This function is intended
to reset all the values of a glyph slot. However, it was not
resetting the values of the advances and `glyph_index`. Reset the
advances and `glyph_index` to zero.
`FDEF` instructions are specified as allowed only in 'prep' or
'fpgm'. FreeType has attempted to prevent their use in the glyph
program, but they were still allowed in glyph programs if defined in
a function defined in 'prep' or 'fpgm' and called from the glyph
program.
Similarly, `IDEF` instructions are specified not to be able to
modify any existing instruction. FreeType has attempted to prevent
their use in the glyph program, but they can still be used like
`FDEF`.
This change stores the initial bytecode range type and disallows the
use of `FDEF` and `IDEF` while running the glyph program.
Most other state is copied from the `TT_Size` into the execution
context. However, it is possible for a glyph program to use `WS` to
write to the storage area or `WCVTP`, `WCVTF`, and `DELTAC[123]` to
write to the control value table.
Allowing any change to the global state from the glyph program is
problematic as the outlines of any given glyph may change based on
the order the glyphs are loaded or even how many times they are
loaded. There exist fonts that write to the storage area or the
control value table in the glyph program, so their use should not be
an error.
Possible solutions to using these in the glyph program are
* ignore the writes;
* value-level copy on write, discard modified values when finished;
* array-level copy on write, discard the copy when finished;
* array-level copy up-front.
Ignoring the writes may break otherwise good uses. A full copy
up-front was implemented, but was quite heavy as even well behaved
fonts required a full copy and the memory management that goes along
with it. Value-level copy on write could use less memory but
requires a great deal more record keeping and complexity. This
change implements array-level copy on write. If any attempt is made
to write to the control value table or the storage area when the
initial bytecode range was in a glyph program, the relevant array
will be copied to a designated storage area and the copy used for
the rest of the glyph program's execution.
* src/truetype/ttinterp.h (TT_ExecContextRec): New fields
`iniRange`, `glyfCvtSize`, `glyfCvt`, `origCvt`, `glyfStoreSize`,
`glyfStorage`, and `origStorage`.
* src/truetype/ttinterp.c (Modify_CVT_Check): New function to handle
`exc->glyfCvt`.
(Write_CVT, Write_CVT_Stretched, Move_CVT, Move_CVT_Stretched): Use
it.
(Ins_WS): Handle `exc->glyfStorage`.
(Ins_FDEF, Ins_IDEF): Updated.
(TT_RunIns): Updated.
(TT_Done_Context): Free 'glyf' CVT working and storage area.
(TT_Load_Context): Fix/add casts.
* src/truetype/ttgload.c (TT_Load_Simple_Glyph): Fix cast.
* src/sfnt/ttcolr.c (get_child_table_pointer): New function to fetch
child table pointer early for all paint formats that compute a child
table pointer.
(read_color_line, read_paint): Updated.
(tt_face_get_colorline_stops): Check `colr->table`.
Reported as
https://bugs.chromium.org/p/chromium/issues/detail?id=1182552
Memory is allocated and the pointer assigned to `rows` inside a
'setjmp' scope. This memory must be freed outside the 'setjmp'
scope after a 'longjmp'. Since `rows` is a local and modified
inside the 'setjmp' scope it must be marked volatile or it will have
an indeterminate value after the 'longjmp'.
* src/sfnt/pngshim.c (Load_SBit_Png): Fix memory leak of `rows`.
We now record `cover' and `area' directly into the linked list. This
makes rendering faster by 10% or even more at larger sizes.
* src/smooth/ftgrays.c (FT_INTEGRATE): Write directly.
(gray_TWorker): Add direct cell reference and remove unused fields.
(gray_set_cell): Consolidate the linked list management and pointers.
(gray_convert_glyph, gray_convert_glyph_inner): Updated.
This change fixes a crash that occurs in `Load_SBit_Png` when
running on a 64-bit Windows OS. A memory access violation exception
would be raised by `setjmp` if the `jmp_buf` is not aligned to a
16-byte memory boundary. This is due to setjmp executing `movdqa`
instructions to store 128-bit XMM registers to memory, which require
correct memory alignment. This problem occurs because
`png_create_read_struct` uses `malloc` and `free` for memory
management, which only guarantees 8-byte alignment on Windows.
Instead, to fix the problem, `png_create_read_struct_2` is used on
64-bit Windows, which allows for user-defined memory allocation and
deallocation callbacks to be specified. These callbacks forward the
allocation and deallocation requests to `_aligned_alloc` and
`_aligned_free`, ensuring that the allocated `png_struct` and
internal `jmp_buf` have the requisite 16-byte alignment.
* src/sfnt/pngshim.c <_WIN64>: Include `malloc.h`.
(malloc_callback, free_callback) <_WIN64>: New functions.
(Load_SBit_Png) <_WIN64>: Use `png_create_read_struct_2` instead of
`png_create_read_struct`
Reported as
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=28148
* src/sfnt/sfwoff2.c (woff2_open_font): Reject fonts that have
multiple tables with the same tag. While not explicitly forbidden
in the OpenType specification, it is implicitly forbidden by
describing a binary search algorithm for tables that only works
reliably if table tags are unique.
This fixes warnings reported by autoupdate.
* builds/unix/ax_pthread.m4: Replace `as_echo` with `AS_ECHO`.
* builds/unix/configure.raw: Remove obsolete `AC_HEADER_STDC`.
Don't escape back quotes in messages for `AC_MSG_WARN`.
<top_level>: Use `TOP_DIR` in `wildcard` function.
(check_out_submodule, copy_submodule): Move down to come after
definition of `all` rule.
Call `mkdir` conditionally.
We use a dummy variable to catch its output. Otherwise the `make`
program is going to interpret the return value of `shell`; this can
cause obscure warning or error messages or even be harmful.
This is for future changes with Meson, which doesn't allow a
different name for its `subprojects` directory. Having both a
`submodules` and a `subprojects` directory is confusing.
* .gitmodules, autogen.sh (copy_submodule_files, DLG_INC_DIR,
DLG_SRC_DIR): Updated.
* builds/toplevel.mk (<top-level>, do-dist),
builds/windows/vc2010/script.bat: Updated.
* src/tools/no-copyright: Updated.
* freetype.h (FT_PaintFormat): Update paint format identifiers after
a specification change. The specification was updated to have
sibling formats, variable and non-variable variants for each.
Reflect that here.
* sfnt/ttcolr.c (read_paint): Remove parsing of variable indices as
the non-variable formats no longer have them.
* include/freetype/internal/compiler-macros.h (FT_COMPARE_DEF):
Add new macro.
* src/base/ftrfork.c, src/bdf/bdflib.c, src/gxvalid/gxvcommn.c,
src/psaux/afmparse.c, src/psnames/psmodule.c, src/type1/t1afm.c,
src/sfnt/sfwoff.c, src/sfnt/sfwoff2.c: Update qsort callbacks.
Fixes#1026 when compiling FreeType with an unusual calling convention
while the C library qsort still expects cdecl.
* include/freetype/freetype.h (FT_Get_Color_Glyph_Paint):
Additional function argument root_transform to control whether
root transform should be returned.
(FT_OpaquePaint): Additional tracking field to denote whether
root transform is to be returned.
* include/freetype/internal/sfnt.h
(TT_Get_Color_Glyph_Paint_Func): Propagate additional argument.
* src/base/ftobjs.c (FT_Get_Color_Glyph_Paint): Ditto.
* src/sfnt/ttcolr.c (tt_face_get_colr_glyph_paint): Return root
transform reflecting the size and tranform configured on
FT_Face.
(read_paint): Initialize and track status of insert_root_transform
flag.
Many projects (e.g., fontconfig, cairo) hardcode the `freetype_dep`
variable name to use FreeType as subproject because that was the
variable name in Centricular's Meson port of FreeType. While they
should stop hardcoding that variable name, it does not cost us
anything to keep using that name to ease transition.
* meson.build (harfbuzz_dep): Do not fall back to HarfBuzz by
default.
Otherwise it causes a dependency cycle:
cairo => fontconfig => freetype2 => harfbuzz => cairo
Meson will still fall back to HarfBuzz subprojects if the `harfbuzz`
option is set to `enabled` instead of `auto` and a
`subprojects/harfbuzz.wrap` file is present. In that case it is the
responsibility of the main project to set the proper options on each
subproject to break the dependency cycle.
Fixes: #1028.
[meson] Fix dependency lookup and generate `ftconfig.h`.
- zlib: If not found on the system, meson can build it as a
subproject. We thus never use the (outdated) zlib support that
comes with FreeType. Doing so has the additional advantage that
the zlib code can be shared with other projects like GLib if both
are subprojects of an application.
- harfbuzz: Build as a subproject if not found on the system.
- 'QUESTION: What if the compiler doesn't support `-D` but uses `/D`
instead as on Windows?' Answer: Meson translate arguments for us.
- visibility: Replace self-made code with meson-specific solution.
* meson.build (ft2_defines): Rewrite logic to set and handle it.
(process_header_command): New variable, previously called
`ftoption_command`.
(ftoption_command, ftconfig_command): New variables.
(zlib_option): Removed.
(zlib_dep): New variable.
(ft2_deps): Updated.
(harfbuzz_dep): Updated.
(ftconfig_h_in, ftconfig_h): New variables.
(ft2_sources): Updated.
(ft2_lib): Updated, handle visibility.
(summary): Updted.
* meson_options.txt (zlib): Updated.
This is copied from GStreamer's meson port of FreeType.
(ft2_sources): Add both debug and resource file (the latter for
Windows only).
(ft2_debug_src): Removed.
This is a new meson mechanism to avoid other projects to hard-code
the `freetype2_dep` variable name in their build definition. It
also ensures that meson does not mix system and subproject versions
of FreeType inside of the same project.
Also remove outdated TODO because `declare_dependency` was already
there.
We remove `static:false` from `find_library('bz2')`.
I don't know whether the previous code was a workaround for an old
meson bug, but at least with version >=0.55.0 (which FreeType uses)
it picks the shared library when both are available.
With this commit, file `freetype2.pc` no longer contains the full path to
file `libbz2.so`; instead, it correctly uses `-lbz2`. Note that this is a
meson bug is still present in the current version (0.57.0).
This ensures good logging output, with all lines having a proper
prefix (if requested).
This is a continuation of a similar patch from 2020-12-02, which
missed some locations.
It's easier to have stubs if FT_DEBUG_LOGGING is undefined than to
modify `ftexport.sym` conditionally.
Problem reported by Alexei.
* src/base/ftdebug.c: Include `ftlogging.h`.
(FT_Trace_Set_Level, FT_Trace_Set_Default_Level, FT_Set_Log_Handler,
FT_Set_Default_Log_Handler) [!FT_DEBUG_LOGGING]: Provide stubs.
This is needed to make commit f1f9705f9 work.
* CMakeLists.txt (HARFBUZZ_MIN_VERSION), builds/unix/configure.raw
(harfbuzz_pkg), meson.build (harfbuzz_dep): Updated.
* sfnt/ttcolr.c (tt_face_get_colr_glyph_paint,
tt_face_get_colorline_stops, tt_face_get_paint): Additional checks
for whether colr table is present. Prevents crashes when these
methods are called on non-COLR fonts.
* include/freetype/config/ftoption.h (TT_SUPPORT_COLRV1): New macro
so that clients can test whether the FreeType checkout that they are
building against supports the 'COLR' v1 API. This is intended to be
a temporary solution until 'COLR' v1 support is released in a
FreeType version and such a check can be made by using the version
number instead.
* src/base/ftobjs.c (FT_Get_Color_Glyph_Paint, FT_Get_Paint_Layers,
FT_Get_Paint, FT_Get_Colorline_Stops): Add basic sanity checks,
check for existence of `FT_Face`, check arguments and delegate calls
for the respective 'COLR' v1 API to the SFNT driver.
* include/freetype/internal/sfnt.h (TT_Get_Color_Glyph_Paint_Func,
TT_Get_Paint_Layers_Func, TT_Get_Colorline_Stops_Func,
TT_Get_Paint_Func): New function pointer types.
(SFNT_Interface): Add them.
(FT_DEFINE_SFNT_INTERFACE): Updated.
* src/sfnt/sfdriver.c (PUT_COLOR_LAYERS_V1): New macro.
(sfnt_interface): Add new function pointers.
* src/sfnt/ttcolr.c (tt_face_get_paint_layers): New function to get
the layers of a `PaintColrLayers` table in the font, using an
`FT_LayerIterator` from an `FT_PaintColrLayers` object retrieved via
`tt_face_get_paint`.
* src/sfnt/ttcolr.h: Updated.
* src/sfnt/ttcolr.c (tt_face_get_colorline_stops): New function to
return the current `FT_ColorStop` object from `FT_ColorStopIterator`.
Also increment the iterator.
* src/sfnt/ttcolr.h: Updated.
* src/sfnt/ttcolr.c (tt_face_get_paint): New function to resolve an
`FT_OpaquePaint` paint reference into an `FT_COLR_Paint` object of a
certain format, which contains the detailed information stored in a
paint of the respective format.
(read_paint): New function to provide the format specific parsing
and to populate the data members of each specific `FT_COLR_Paint`
subtype.
(read_color_line): New function to parse retrieved color line
information into an `FT_ColorLine` object, which has information
about the color line extend mode as well as an
`FT_ColorStopIterator` object.
* src/sfnt/ttcolr.h: Updated.
* src/sfnt/ttcolr.c (BaseGlyphV1Record): New structure.
(tt_face_load_colr): Handle version 1 table header.
(find_base_glyph_v1_record): New auxiliary function.
(tt_face_get_colr_glyph_paint): New function to find the root
`FT_OpaquePaint` object for a given glyph ID.
* src/sfnt/ttcolr.h: Updated.
* include/freetype/freetype.h (FT_Get_Color_Glyph_Paint): New method
for retrieving the root paint object for a color glyph by specifying
a glyph ID.
(FT_Get_Paint_Layers): New method for retrieving the layers of a
`PaintColorGlyph`.
(FT_Get_ColorLine_Stops): New method for retrieving the stops of a
color.
(FT_Get_Paint): New method for resolving an `FT_OpaquePaint` into an
`FT_COLR_Paint` object.
* include/freetype/freetype.h (FT_PaintFormat, FT_ColorStopIterator,
FT_ColorIndex, FT_ColorStop, FT_PaintExtend, FT_ColorLine,
FT_Affine23, FT_CompositeMode, FT_OpaquePaint, FT_PaintColrLayers,
FT_PaintSolid, FT_PaintLinearGradient, FT_PaintRadialGradient,
FT_PaintGlyph, FT_PaintColrGlyph, FT_PaintTransformed,
FT_PaintTranslate, FT_PaintRotate, FT_PaintSkew, FT_PaintComposite,
FT_COLR_Paint): Adding structs and enum to represent paint format,
color stop information, gradient extend information, structs to
reference paint offsets, and to define transforms and compositions.
Adding a union type to represent the union of the structs,
distinguished by `FT_PaintFormat`.
* include/freetype/config/ftmodule.h: Add both the 'sfd' and 'bsfd'
renderers to the list of modules.
* CMakeLists.txt (BASE_SRCS): Add 'sdf' single-object module.
* src/sdf/module.mk, src/sfd/rules.mk: New files.
* src/sdf/ftsdf.h (ft_sdf_raster): New forward declaration.
* include/freetype/ftmoderr.h (FT_MODERRDEF): Add error definition
for the 'sdf' module.
* include/freetype/internal/fttrace.h (FT_TRACE_DEF): Add trace
definition for the `sdf' module.
* modules.cfg (RASTER_MODULES): Add the `sdf' module to the list of
rasterizers.
* src/sdf/ftsdf.c (sdf_generate_bounding_box): New function, which
is an optimized version of `sdf_generate`.
(sdf_generate_subdivision): New function.
* src/sdf/ftsdf.c (sdf_generate): New function, currently disabled.
This is a proof-of-concept implementation: It doesn't use any
optimization, it simply checks all grid points against all contours.
* src/sdf/ftsdf.c (get_min_distance_line, get_min_distance_conic,
get_min_distance_cubic): New functions. Note that
`get_min_distance_conic` comes with two implementations (using an
analytical and an iterative method, to be controlled with the
`USE_NEWTON_FOR_CONIC` macro).
* src/sdf/ftsdf.c (FT_DEBUG_INNER, FT_ASSIGNP_INNER)
[FT_DEBUG_LEVEL_TRACE && FT_DEBUG_MEMORY]: New macros.
(SDF_MemoryUser) [FT_DEBUG_LEVEL_TRACE && FT_DEBUG_MEMORY]: New
struct for memory usage tracing.
(sdf_alloc, sdf_free) [FT_DEBUG_LEVEL_TRACE && FT_DEBUG_MEMORY]: New
functions for memory usage tracing.
(SDF_ALLOC, SDF_FREE): New macros for memory management.
(SDF_MEMORY_TRACKER_DECLARE, SDF_MEMORY_TRACKER_SETUP,
SDF_MEMORY_TRACKER_DONE): New macros to set up memory usage tracing.
(USE_NEWTON_FOR_CONIC, MAX_NEWTON_DIVISIONS, MAX_NEWTON_STEPS,
CORNER_CHECK_EPSILON, CG_DIMEN): New configuration macros for
controlling the process of finding the shortest distance.
(MUL_26D6, VEC_26D6_DOT): New auxiliary macros.
(SDF_TRaster, SDF_Edge, SDF_Contour, SDF_Shape, SDF_Signed_Distance,
SDF_Params): New structs for setting up SDF data.
(SDF_Edge_Type, SDF_Contour_Orientation): New enums for SDF data.
(zero_vector, null_edge, null_contour, null_shape, max_sdf): Useful
constants.
(sdf_edge_new, sdf_edge_done, sdf_contour_new, sdf_contour_done,
sdf_shape_new, sdf_shape_done): New constructors and destructors.
Here is a breakdown of what the files will contain.
* src/sdf/ftsdfrend.c, src/sdf/ftsdfrend.h: The 'sdf' and 'bsdf'
renderers.
* src/sdf/ftsdf.c, src/sdf/ftsdf.h: The rasterizer for the 'sdf'
renderer.
* src/sdf/ftbsdf.c, src/sdf/ftbsdf.h: The rasterizer for the 'bsdf'
renderer.
* src/sdf/ftsdfcommon.h: Commmon properties and functions for both
rasterizers.
* src/sdf/ftsdferrs.h: Common error defines.
* src/sdf/sdf.c: For building a single object of the entire module.
* src/base/ftobjs.c (FT_Render_Glyph_Internal): Do not return if the
glyph's slot format is `FT_GLYPH_FORMAT_BITMAP`. The forthcoming
'bsdf' renderer will require bitmaps for processing.
* src/base/ftobjs.c (ft_add_renderer, ft_remove_renderer): Remove
renderer's glyph format check before adding and removing them. The
'bsdf' renderer will have a format `FT_GLYPH_FORMAT_BITMAP`.
* include/freetype/freetype.h (FT_Render_Mode): Add new render mode
`FT_RENDER_MODE_SDF`, which will be used to generate SDF.
* include/freetype/ftimage.h (FT_Pixel_Mode): Add new pixel mode
`FT_PIXEL_MODE_GRAY16`, which will be the output of the 'sdf'
module.
(FT_RASTER_FLAG_SDF): New raster flag to be used internally by the
'sdf' module.
* include/freetype/fttypes.h (FT_F6Dot10): New data type.
* src/base/ftobjs.c (FT_Render_Glyph_Internal): Do not return if the
glyph's slot format is `FT_GLYPH_FORMAT_BITMAP`. The forthcoming
'bsdf' renderer will require bitmaps for processing.
* src/base/ftobjs.c (ft_add_renderer, ft_remove_renderer): Remove
renderer's glyph format check before adding and removing them. The
'bsdf' renderer will have a format `FT_GLYPH_FORMAT_BITMAP`.
The old code used to divide the darkening amount by em_ratio twice,
leading to unnecessarily bold stems on certain fonts with higher
units per em (e.g. Inter). This patch fixes it.
The return value of af_loader_compute_darkening was also changed to
use 16.16 fixed point to get rid of a redundant truncation operation.
This should slightly improve the precision, although it's still
bottlenecked by the emboldening function, which uses 26.6 fixed point.
* src/autofit/afloader.[ch]
(af_loader_compute_darkening): Return FT_Fixed.
(af_loader_embolden_glyph_in_slot): Revise calculations.
* src/truetype/ttgload.c (tt_get_metrics, load_truetype_glyph):
Previously, the code would populate the phantom points before
calling the `get_glyph_metrics` callback. For formats like PCL XL
format 1, class 2 downloaded fonts (where metrics are removed from
the TTF header), this causes problems when the hinting program uses
the phantom points (misplaced and distorted glyphs) due to the
metrics being unset (all zeros).
(tt_get_metrics_incr_overrides): Renamed to...
(tt_get_metrics_incremental): ... this. Updated caller
* include/freetype/ftincrem.h: Update the documentation to make it
clearer that `get_glyph_metrics` is to retrieve metrics from a
non-standard source, but *not* for the purpose of imposing custom
metrics.
* autogen.sh (copy_submodule_file), builds/toplevel.mk: Redirect
stderr to `/dev/null`.
* builds/toplevel.mk: Move code block to handle 'dlg' stuff into
`check_platform` conditional.
Also fix wildcard expressions for guarding `git submodule` commands.
Also make file copying work with non-Unix platforms (untested).
Other compilers are unchanged.
* builds/compiler/gcc-dev.mk, builds/compiler/gcc.mk (ANSIFLAGS):
s/-ansi/-std=c99/.
* builds/freetype.mk (FT_CFLAGS): Remove `-std=c99`.
* builds/unix/configure.raw: Handle C99.
Remove no longer needed test for gcc 4.6 and earlier.
* src/dlg/dlgwrap.c: Duplicate some feature test macros from
`dlg.c`, which must come first before loading standard headers. For
example, `freetype.h` loads `stdio.h` if compiled in debug mode.
* builds/unix/ax_pthread.m4: New file, taken from 'autoconf-archive'
git repository.
* builds/unix/configure.raw: Check for 'pthread'; also check whether
it works.
Based on a patch by Priyesh.
* include/freetype/internal/fttrace.h (FT_MAX_TRACE_LEVEL_LENGTH):
New macro.
* src/base/ftdebug.c, builds/windows/ftdebug.c (ft_log_handler):
Print logs after a fixed width to handle different lengths of
`FT_COMPONENT` entries.
Use `ft_strrchr` to check for final newline character.
We only support Visual C++ 2010 and newer.
* builds/windows/vc2010/script.bat: New windows batch file to copy
necessary 'dlg' files from `submodules/dlg` to `src/dlg`. This file
is used as a pre-built event in Visual C++.
* builds/windows/ftdebug.c: Synchronize with `src/base/ftdebug.c`.
* builds/windows/vc2010/freetype.vcxproj.filters: Add
`src/dlgwrap.c`.
* builds/windows/vc2010/freetype.vcxproj
(AdditionalIncludeDirectories): Add include files of dlg for 'Debug'
and 'Debug Static' configurations on both 'x64' and 'win32'
platforms.
(PreprocessorDefinitions): Add `FT_LOGGING` for 'Debug' and 'Debug
Static' configurations on both 'x64' and 'win32' platforms.
Add `DLG_STATIC' for 'Debug' configuration on 'x64' and 'win32'
platforms.
(DisableLanguageExtensions): We need to disable the `/Za` option
when building 'dlg' with FreeType as 'dlg' strictly follows the C99
standard. Visual C++ produces behaves unexpectedly when
compiling a C99 file with `/Za` option enabled.
* include/freetype/ftlogging.h (FT_Custom_Log_Handler): New function
typedef to store the custom callback logging function.
(FT_Set_Log_Handler, FT_Set_Default_Log_Handler): New functions to
set and reset custom log handler.
* include/freetype/internal/ftdebug.h (custom_output_handler): New
variable to support a custom callback logging function.
(FT_Logging_Callback): A new function typedef to print log using
custom callback logging function, which is set using
`FT_Set_Log_Handler`.
(FT_Log): Use it.
* src/base/ftdebug.c (FT_Set_Log_Handler,
FT_Set_Default_Log_Handler, FT_Logging_Callback): Add function
definitions.
* include/freetype/ftlogging.h: New header file.
* include/freetype/internal/ftdebug.h [FT_LOGGING]: Include
`ftlogging.h`.
* src/base/ftdebug.c (ft_custom_trace_level): New variable.
(ft_debug_init): Update to support change of levels of tracing
components of FreeType at run-time.
(FT_Trace_Set_Level): New function to change the levels of tracing
components at run-time.
(FT_Trace_Set_Default_Level): New function to reset the levels of
tracing components back to default.
Alexei Podtelezhnikov