1 /****************************************************************************
2  *
3  * ftoption.h
4  *
5  *   User-selectable configuration macros (specification only).
6  *
7  * Copyright (C) 1996-2022 by
8  * David Turner, Robert Wilhelm, and Werner Lemberg.
9  *
10  * This file is part of the FreeType project, and may only be used,
11  * modified, and distributed under the terms of the FreeType project
12  * license, LICENSE.TXT.  By continuing to use, modify, or distribute
13  * this file you indicate that you have read the license and
14  * understand and accept it fully.
15  *
16  */
17 
18 
19 #ifndef FTOPTION_H_
20 #define FTOPTION_H_
21 
22 
23 #include <ft2build.h>
24 
25 
26 FT_BEGIN_HEADER
27 
28   /**************************************************************************
29    *
30    *                USER-SELECTABLE CONFIGURATION MACROS
31    *
32    * This file contains the default configuration macro definitions for a
33    * standard build of the FreeType library.  There are three ways to use
34    * this file to build project-specific versions of the library:
35    *
36    * - You can modify this file by hand, but this is not recommended in
37    *   cases where you would like to build several versions of the library
38    *   from a single source directory.
39    *
40    * - You can put a copy of this file in your build directory, more
41    *   precisely in `$BUILD/freetype/config/ftoption.h`, where `$BUILD` is
42    *   the name of a directory that is included _before_ the FreeType include
43    *   path during compilation.
44    *
45    *   The default FreeType Makefiles use the build directory
46    *   `builds/<system>` by default, but you can easily change that for your
47    *   own projects.
48    *
49    * - Copy the file <ft2build.h> to `$BUILD/ft2build.h` and modify it
50    *   slightly to pre-define the macro `FT_CONFIG_OPTIONS_H` used to locate
51    *   this file during the build.  For example,
52    *
53    *   ```
54    *     #define FT_CONFIG_OPTIONS_H  <myftoptions.h>
55    *     #include <freetype/config/ftheader.h>
56    *   ```
57    *
58    *   will use `$BUILD/myftoptions.h` instead of this file for macro
59    *   definitions.
60    *
61    *   Note also that you can similarly pre-define the macro
62    *   `FT_CONFIG_MODULES_H` used to locate the file listing of the modules
63    *   that are statically linked to the library at compile time.  By
64    *   default, this file is `<freetype/config/ftmodule.h>`.
65    *
66    * We highly recommend using the third method whenever possible.
67    *
68    */
69 
70 
71   /*************************************************************************/
72   /*************************************************************************/
73   /****                                                                 ****/
74   /**** G E N E R A L   F R E E T Y P E   2   C O N F I G U R A T I O N ****/
75   /****                                                                 ****/
76   /*************************************************************************/
77   /*************************************************************************/
78 
79 
80   /*#************************************************************************
81    *
82    * If you enable this configuration option, FreeType recognizes an
83    * environment variable called `FREETYPE_PROPERTIES`, which can be used to
84    * control the various font drivers and modules.  The controllable
85    * properties are listed in the section @properties.
86    *
87    * You have to undefine this configuration option on platforms that lack
88    * the concept of environment variables (and thus don't have the `getenv`
89    * function), for example Windows CE.
90    *
91    * `FREETYPE_PROPERTIES` has the following syntax form (broken here into
92    * multiple lines for better readability).
93    *
94    * ```
95    *   <optional whitespace>
96    *   <module-name1> ':'
97    *   <property-name1> '=' <property-value1>
98    *   <whitespace>
99    *   <module-name2> ':'
100    *   <property-name2> '=' <property-value2>
101    *   ...
102    * ```
103    *
104    * Example:
105    *
106    * ```
107    *   FREETYPE_PROPERTIES=truetype:interpreter-version=35 \
108    *                       cff:no-stem-darkening=1
109    * ```
110    *
111    */
112 #define FT_CONFIG_OPTION_ENVIRONMENT_PROPERTIES
113 
114 
115   /**************************************************************************
116    *
117    * Uncomment the line below if you want to activate LCD rendering
118    * technology similar to ClearType in this build of the library.  This
119    * technology triples the resolution in the direction color subpixels.  To
120    * mitigate color fringes inherent to this technology, you also need to
121    * explicitly set up LCD filtering.
122    *
123    * When this macro is not defined, FreeType offers alternative LCD
124    * rendering technology that produces excellent output.
125    */
126 /* #define FT_CONFIG_OPTION_SUBPIXEL_RENDERING */
127 
128 
129   /**************************************************************************
130    *
131    * Many compilers provide a non-ANSI 64-bit data type that can be used by
132    * FreeType to speed up some computations.  However, this will create some
133    * problems when compiling the library in strict ANSI mode.
134    *
135    * For this reason, the use of 64-bit integers is normally disabled when
136    * the `__STDC__` macro is defined.  You can however disable this by
137    * defining the macro `FT_CONFIG_OPTION_FORCE_INT64` here.
138    *
139    * For most compilers, this will only create compilation warnings when
140    * building the library.
141    *
142    * ObNote: The compiler-specific 64-bit integers are detected in the
143    *         file `ftconfig.h` either statically or through the `configure`
144    *         script on supported platforms.
145    */
146 #undef FT_CONFIG_OPTION_FORCE_INT64
147 
148 
149   /**************************************************************************
150    *
151    * If this macro is defined, do not try to use an assembler version of
152    * performance-critical functions (e.g., @FT_MulFix).  You should only do
153    * that to verify that the assembler function works properly, or to execute
154    * benchmark tests of the various implementations.
155    */
156 /* #define FT_CONFIG_OPTION_NO_ASSEMBLER */
157 
158 
159   /**************************************************************************
160    *
161    * If this macro is defined, try to use an inlined assembler version of the
162    * @FT_MulFix function, which is a 'hotspot' when loading and hinting
163    * glyphs, and which should be executed as fast as possible.
164    *
165    * Note that if your compiler or CPU is not supported, this will default to
166    * the standard and portable implementation found in `ftcalc.c`.
167    */
168 #define FT_CONFIG_OPTION_INLINE_MULFIX
169 
170 
171   /**************************************************************************
172    *
173    * LZW-compressed file support.
174    *
175    *   FreeType now handles font files that have been compressed with the
176    *   `compress` program.  This is mostly used to parse many of the PCF
177    *   files that come with various X11 distributions.  The implementation
178    *   uses NetBSD's `zopen` to partially uncompress the file on the fly (see
179    *   `src/lzw/ftgzip.c`).
180    *
181    *   Define this macro if you want to enable this 'feature'.
182    */
183 #define FT_CONFIG_OPTION_USE_LZW
184 
185 
186   /**************************************************************************
187    *
188    * Gzip-compressed file support.
189    *
190    *   FreeType now handles font files that have been compressed with the
191    *   `gzip` program.  This is mostly used to parse many of the PCF files
192    *   that come with XFree86.  The implementation uses 'zlib' to partially
193    *   uncompress the file on the fly (see `src/gzip/ftgzip.c`).
194    *
195    *   Define this macro if you want to enable this 'feature'.  See also the
196    *   macro `FT_CONFIG_OPTION_SYSTEM_ZLIB` below.
197    */
198 #define FT_CONFIG_OPTION_USE_ZLIB
199 
200 
201   /**************************************************************************
202    *
203    * ZLib library selection
204    *
205    *   This macro is only used when `FT_CONFIG_OPTION_USE_ZLIB` is defined.
206    *   It allows FreeType's 'ftgzip' component to link to the system's
207    *   installation of the ZLib library.  This is useful on systems like
208    *   Unix or VMS where it generally is already available.
209    *
210    *   If you let it undefined, the component will use its own copy of the
211    *   zlib sources instead.  These have been modified to be included
212    *   directly within the component and **not** export external function
213    *   names.  This allows you to link any program with FreeType _and_ ZLib
214    *   without linking conflicts.
215    *
216    *   Do not `#undef` this macro here since the build system might define
217    *   it for certain configurations only.
218    *
219    *   If you use a build system like cmake or the `configure` script,
220    *   options set by those programs have precedence, overwriting the value
221    *   here with the configured one.
222    *
223    *   If you use the GNU make build system directly (that is, without the
224    *   `configure` script) and you define this macro, you also have to pass
225    *   `SYSTEM_ZLIB=yes` as an argument to make.
226    */
227 /* #define FT_CONFIG_OPTION_SYSTEM_ZLIB */
228 
229 
230   /**************************************************************************
231    *
232    * Bzip2-compressed file support.
233    *
234    *   FreeType now handles font files that have been compressed with the
235    *   `bzip2` program.  This is mostly used to parse many of the PCF files
236    *   that come with XFree86.  The implementation uses `libbz2` to partially
237    *   uncompress the file on the fly (see `src/bzip2/ftbzip2.c`).  Contrary
238    *   to gzip, bzip2 currently is not included and need to use the system
239    *   available bzip2 implementation.
240    *
241    *   Define this macro if you want to enable this 'feature'.
242    *
243    *   If you use a build system like cmake or the `configure` script,
244    *   options set by those programs have precedence, overwriting the value
245    *   here with the configured one.
246    */
247 /* #define FT_CONFIG_OPTION_USE_BZIP2 */
248 
249 
250   /**************************************************************************
251    *
252    * Define to disable the use of file stream functions and types, `FILE`,
253    * `fopen`, etc.  Enables the use of smaller system libraries on embedded
254    * systems that have multiple system libraries, some with or without file
255    * stream support, in the cases where file stream support is not necessary
256    * such as memory loading of font files.
257    */
258 /* #define FT_CONFIG_OPTION_DISABLE_STREAM_SUPPORT */
259 
260 
261   /**************************************************************************
262    *
263    * PNG bitmap support.
264    *
265    *   FreeType now handles loading color bitmap glyphs in the PNG format.
266    *   This requires help from the external libpng library.  Uncompressed
267    *   color bitmaps do not need any external libraries and will be supported
268    *   regardless of this configuration.
269    *
270    *   Define this macro if you want to enable this 'feature'.
271    *
272    *   If you use a build system like cmake or the `configure` script,
273    *   options set by those programs have precedence, overwriting the value
274    *   here with the configured one.
275    */
276 /* #define FT_CONFIG_OPTION_USE_PNG */
277 
278 
279   /**************************************************************************
280    *
281    * HarfBuzz support.
282    *
283    *   FreeType uses the HarfBuzz library to improve auto-hinting of OpenType
284    *   fonts.  If available, many glyphs not directly addressable by a font's
285    *   character map will be hinted also.
286    *
287    *   Define this macro if you want to enable this 'feature'.
288    *
289    *   If you use a build system like cmake or the `configure` script,
290    *   options set by those programs have precedence, overwriting the value
291    *   here with the configured one.
292    */
293 /* #define FT_CONFIG_OPTION_USE_HARFBUZZ */
294 
295 
296   /**************************************************************************
297    *
298    * Brotli support.
299    *
300    *   FreeType uses the Brotli library to provide support for decompressing
301    *   WOFF2 streams.
302    *
303    *   Define this macro if you want to enable this 'feature'.
304    *
305    *   If you use a build system like cmake or the `configure` script,
306    *   options set by those programs have precedence, overwriting the value
307    *   here with the configured one.
308    */
309 /* #define FT_CONFIG_OPTION_USE_BROTLI */
310 
311 
312   /**************************************************************************
313    *
314    * Glyph Postscript Names handling
315    *
316    *   By default, FreeType 2 is compiled with the 'psnames' module.  This
317    *   module is in charge of converting a glyph name string into a Unicode
318    *   value, or return a Macintosh standard glyph name for the use with the
319    *   TrueType 'post' table.
320    *
321    *   Undefine this macro if you do not want 'psnames' compiled in your
322    *   build of FreeType.  This has the following effects:
323    *
324    *   - The TrueType driver will provide its own set of glyph names, if you
325    *     build it to support postscript names in the TrueType 'post' table,
326    *     but will not synthesize a missing Unicode charmap.
327    *
328    *   - The Type~1 driver will not be able to synthesize a Unicode charmap
329    *     out of the glyphs found in the fonts.
330    *
331    *   You would normally undefine this configuration macro when building a
332    *   version of FreeType that doesn't contain a Type~1 or CFF driver.
333    */
334 #define FT_CONFIG_OPTION_POSTSCRIPT_NAMES
335 
336 
337   /**************************************************************************
338    *
339    * Postscript Names to Unicode Values support
340    *
341    *   By default, FreeType~2 is built with the 'psnames' module compiled in.
342    *   Among other things, the module is used to convert a glyph name into a
343    *   Unicode value.  This is especially useful in order to synthesize on
344    *   the fly a Unicode charmap from the CFF/Type~1 driver through a big
345    *   table named the 'Adobe Glyph List' (AGL).
346    *
347    *   Undefine this macro if you do not want the Adobe Glyph List compiled
348    *   in your 'psnames' module.  The Type~1 driver will not be able to
349    *   synthesize a Unicode charmap out of the glyphs found in the fonts.
350    */
351 #define FT_CONFIG_OPTION_ADOBE_GLYPH_LIST
352 
353 
354   /**************************************************************************
355    *
356    * Support for Mac fonts
357    *
358    *   Define this macro if you want support for outline fonts in Mac format
359    *   (mac dfont, mac resource, macbinary containing a mac resource) on
360    *   non-Mac platforms.
361    *
362    *   Note that the 'FOND' resource isn't checked.
363    */
364 #define FT_CONFIG_OPTION_MAC_FONTS
365 
366 
367   /**************************************************************************
368    *
369    * Guessing methods to access embedded resource forks
370    *
371    *   Enable extra Mac fonts support on non-Mac platforms (e.g., GNU/Linux).
372    *
373    *   Resource forks which include fonts data are stored sometimes in
374    *   locations which users or developers don't expected.  In some cases,
375    *   resource forks start with some offset from the head of a file.  In
376    *   other cases, the actual resource fork is stored in file different from
377    *   what the user specifies.  If this option is activated, FreeType tries
378    *   to guess whether such offsets or different file names must be used.
379    *
380    *   Note that normal, direct access of resource forks is controlled via
381    *   the `FT_CONFIG_OPTION_MAC_FONTS` option.
382    */
383 #ifdef FT_CONFIG_OPTION_MAC_FONTS
384 #define FT_CONFIG_OPTION_GUESSING_EMBEDDED_RFORK
385 #endif
386 
387 
388   /**************************************************************************
389    *
390    * Allow the use of `FT_Incremental_Interface` to load typefaces that
391    * contain no glyph data, but supply it via a callback function.  This is
392    * required by clients supporting document formats which supply font data
393    * incrementally as the document is parsed, such as the Ghostscript
394    * interpreter for the PostScript language.
395    */
396 #define FT_CONFIG_OPTION_INCREMENTAL
397 
398 
399   /**************************************************************************
400    *
401    * The size in bytes of the render pool used by the scan-line converter to
402    * do all of its work.
403    */
404 #define FT_RENDER_POOL_SIZE  16384L
405 
406 
407   /**************************************************************************
408    *
409    * FT_MAX_MODULES
410    *
411    *   The maximum number of modules that can be registered in a single
412    *   FreeType library object.  32~is the default.
413    */
414 #define FT_MAX_MODULES  32
415 
416 
417   /**************************************************************************
418    *
419    * Debug level
420    *
421    *   FreeType can be compiled in debug or trace mode.  In debug mode,
422    *   errors are reported through the 'ftdebug' component.  In trace mode,
423    *   additional messages are sent to the standard output during execution.
424    *
425    *   Define `FT_DEBUG_LEVEL_ERROR` to build the library in debug mode.
426    *   Define `FT_DEBUG_LEVEL_TRACE` to build it in trace mode.
427    *
428    *   Don't define any of these macros to compile in 'release' mode!
429    *
430    *   Do not `#undef` these macros here since the build system might define
431    *   them for certain configurations only.
432    */
433 /* #define FT_DEBUG_LEVEL_ERROR */
434 /* #define FT_DEBUG_LEVEL_TRACE */
435 
436 
437   /**************************************************************************
438    *
439    * Logging
440    *
441    *   Compiling FreeType in debug or trace mode makes FreeType write error
442    *   and trace log messages to `stderr`.  Enabling this macro
443    *   automatically forces the `FT_DEBUG_LEVEL_ERROR` and
444    *   `FT_DEBUG_LEVEL_TRACE` macros and allows FreeType to write error and
445    *   trace log messages to a file instead of `stderr`.  For writing logs
446    *   to a file, FreeType uses an the external `dlg` library (the source
447    *   code is in `src/dlg`).
448    *
449    *   This option needs a C99 compiler.
450    */
451 /* #define FT_DEBUG_LOGGING */
452 
453 
454   /**************************************************************************
455    *
456    * Autofitter debugging
457    *
458    *   If `FT_DEBUG_AUTOFIT` is defined, FreeType provides some means to
459    *   control the autofitter behaviour for debugging purposes with global
460    *   boolean variables (consequently, you should **never** enable this
461    *   while compiling in 'release' mode):
462    *
463    *   ```
464    *     _af_debug_disable_horz_hints
465    *     _af_debug_disable_vert_hints
466    *     _af_debug_disable_blue_hints
467    *   ```
468    *
469    *   Additionally, the following functions provide dumps of various
470    *   internal autofit structures to stdout (using `printf`):
471    *
472    *   ```
473    *     af_glyph_hints_dump_points
474    *     af_glyph_hints_dump_segments
475    *     af_glyph_hints_dump_edges
476    *     af_glyph_hints_get_num_segments
477    *     af_glyph_hints_get_segment_offset
478    *   ```
479    *
480    *   As an argument, they use another global variable:
481    *
482    *   ```
483    *     _af_debug_hints
484    *   ```
485    *
486    *   Please have a look at the `ftgrid` demo program to see how those
487    *   variables and macros should be used.
488    *
489    *   Do not `#undef` these macros here since the build system might define
490    *   them for certain configurations only.
491    */
492 /* #define FT_DEBUG_AUTOFIT */
493 
494 
495   /**************************************************************************
496    *
497    * Memory Debugging
498    *
499    *   FreeType now comes with an integrated memory debugger that is capable
500    *   of detecting simple errors like memory leaks or double deletes.  To
501    *   compile it within your build of the library, you should define
502    *   `FT_DEBUG_MEMORY` here.
503    *
504    *   Note that the memory debugger is only activated at runtime when when
505    *   the _environment_ variable `FT2_DEBUG_MEMORY` is defined also!
506    *
507    *   Do not `#undef` this macro here since the build system might define it
508    *   for certain configurations only.
509    */
510 /* #define FT_DEBUG_MEMORY */
511 
512 
513   /**************************************************************************
514    *
515    * Module errors
516    *
517    *   If this macro is set (which is _not_ the default), the higher byte of
518    *   an error code gives the module in which the error has occurred, while
519    *   the lower byte is the real error code.
520    *
521    *   Setting this macro makes sense for debugging purposes only, since it
522    *   would break source compatibility of certain programs that use
523    *   FreeType~2.
524    *
525    *   More details can be found in the files `ftmoderr.h` and `fterrors.h`.
526    */
527 #undef FT_CONFIG_OPTION_USE_MODULE_ERRORS
528 
529 
530   /**************************************************************************
531    *
532    * OpenType SVG Glyph Support
533    *
534    *   Setting this macro enables support for OpenType SVG glyphs.  By
535    *   default, FreeType can only fetch SVG documents.  However, it can also
536    *   render them if external rendering hook functions are plugged in at
537    *   runtime.
538    *
539    *   More details on the hooks can be found in file `otsvg.h`.
540    */
541 #define FT_CONFIG_OPTION_SVG
542 
543 
544   /**************************************************************************
545    *
546    * Error Strings
547    *
548    *   If this macro is set, `FT_Error_String` will return meaningful
549    *   descriptions.  This is not enabled by default to reduce the overall
550    *   size of FreeType.
551    *
552    *   More details can be found in the file `fterrors.h`.
553    */
554 /* #define FT_CONFIG_OPTION_ERROR_STRINGS */
555 
556 
557   /*************************************************************************/
558   /*************************************************************************/
559   /****                                                                 ****/
560   /****        S F N T   D R I V E R    C O N F I G U R A T I O N       ****/
561   /****                                                                 ****/
562   /*************************************************************************/
563   /*************************************************************************/
564 
565 
566   /**************************************************************************
567    *
568    * Define `TT_CONFIG_OPTION_EMBEDDED_BITMAPS` if you want to support
569    * embedded bitmaps in all formats using the 'sfnt' module (namely
570    * TrueType~& OpenType).
571    */
572 #define TT_CONFIG_OPTION_EMBEDDED_BITMAPS
573 
574 
575   /**************************************************************************
576    *
577    * Define `TT_CONFIG_OPTION_COLOR_LAYERS` if you want to support colored
578    * outlines (from the 'COLR'/'CPAL' tables) in all formats using the 'sfnt'
579    * module (namely TrueType~& OpenType).
580    */
581 #define TT_CONFIG_OPTION_COLOR_LAYERS
582 
583 
584   /**************************************************************************
585    *
586    * Define `TT_CONFIG_OPTION_POSTSCRIPT_NAMES` if you want to be able to
587    * load and enumerate the glyph Postscript names in a TrueType or OpenType
588    * file.
589    *
590    * Note that when you do not compile the 'psnames' module by undefining the
591    * above `FT_CONFIG_OPTION_POSTSCRIPT_NAMES`, the 'sfnt' module will
592    * contain additional code used to read the PS Names table from a font.
593    *
594    * (By default, the module uses 'psnames' to extract glyph names.)
595    */
596 #define TT_CONFIG_OPTION_POSTSCRIPT_NAMES
597 
598 
599   /**************************************************************************
600    *
601    * Define `TT_CONFIG_OPTION_SFNT_NAMES` if your applications need to access
602    * the internal name table in a SFNT-based format like TrueType or
603    * OpenType.  The name table contains various strings used to describe the
604    * font, like family name, copyright, version, etc.  It does not contain
605    * any glyph name though.
606    *
607    * Accessing SFNT names is done through the functions declared in
608    * `ftsnames.h`.
609    */
610 #define TT_CONFIG_OPTION_SFNT_NAMES
611 
612 
613   /**************************************************************************
614    *
615    * TrueType CMap support
616    *
617    *   Here you can fine-tune which TrueType CMap table format shall be
618    *   supported.
619    */
620 #define TT_CONFIG_CMAP_FORMAT_0
621 #define TT_CONFIG_CMAP_FORMAT_2
622 #define TT_CONFIG_CMAP_FORMAT_4
623 #define TT_CONFIG_CMAP_FORMAT_6
624 #define TT_CONFIG_CMAP_FORMAT_8
625 #define TT_CONFIG_CMAP_FORMAT_10
626 #define TT_CONFIG_CMAP_FORMAT_12
627 #define TT_CONFIG_CMAP_FORMAT_13
628 #define TT_CONFIG_CMAP_FORMAT_14
629 
630 
631   /*************************************************************************/
632   /*************************************************************************/
633   /****                                                                 ****/
634   /****    T R U E T Y P E   D R I V E R    C O N F I G U R A T I O N   ****/
635   /****                                                                 ****/
636   /*************************************************************************/
637   /*************************************************************************/
638 
639   /**************************************************************************
640    *
641    * Define `TT_CONFIG_OPTION_BYTECODE_INTERPRETER` if you want to compile a
642    * bytecode interpreter in the TrueType driver.
643    *
644    * By undefining this, you will only compile the code necessary to load
645    * TrueType glyphs without hinting.
646    *
647    * Do not `#undef` this macro here, since the build system might define it
648    * for certain configurations only.
649    */
650 #define TT_CONFIG_OPTION_BYTECODE_INTERPRETER
651 
652 
653   /**************************************************************************
654    *
655    * Define `TT_CONFIG_OPTION_SUBPIXEL_HINTING` if you want to compile
656    * subpixel hinting support into the TrueType driver.  This modifies the
657    * TrueType hinting mechanism when anything but `FT_RENDER_MODE_MONO` is
658    * requested.
659    *
660    * In particular, it modifies the bytecode interpreter to interpret (or
661    * not) instructions in a certain way so that all TrueType fonts look like
662    * they do in a Windows ClearType (DirectWrite) environment.  See [1] for a
663    * technical overview on what this means.  See `ttinterp.h` for more
664    * details on the LEAN option.
665    *
666    * There are three possible values.
667    *
668    * Value 1:
669    *   This value is associated with the 'Infinality' moniker, contributed by
670    *   an individual nicknamed Infinality with the goal of making TrueType
671    *   fonts render better than on Windows.  A high amount of configurability
672    *   and flexibility, down to rules for single glyphs in fonts, but also
673    *   very slow.  Its experimental and slow nature and the original
674    *   developer losing interest meant that this option was never enabled in
675    *   default builds.
676    *
677    *   The corresponding interpreter version is v38.
678    *
679    * Value 2:
680    *   The new default mode for the TrueType driver.  The Infinality code
681    *   base was stripped to the bare minimum and all configurability removed
682    *   in the name of speed and simplicity.  The configurability was mainly
683    *   aimed at legacy fonts like 'Arial', 'Times New Roman', or 'Courier'.
684    *   Legacy fonts are fonts that modify vertical stems to achieve clean
685    *   black-and-white bitmaps.  The new mode focuses on applying a minimal
686    *   set of rules to all fonts indiscriminately so that modern and web
687    *   fonts render well while legacy fonts render okay.
688    *
689    *   The corresponding interpreter version is v40.
690    *
691    * Value 3:
692    *   Compile both, making both v38 and v40 available (the latter is the
693    *   default).
694    *
695    * By undefining these, you get rendering behavior like on Windows without
696    * ClearType, i.e., Windows XP without ClearType enabled and Win9x
697    * (interpreter version v35).  Or not, depending on how much hinting blood
698    * and testing tears the font designer put into a given font.  If you
699    * define one or both subpixel hinting options, you can switch between
700    * between v35 and the ones you define (using `FT_Property_Set`).
701    *
702    * This option requires `TT_CONFIG_OPTION_BYTECODE_INTERPRETER` to be
703    * defined.
704    *
705    * [1]
706    * https://www.microsoft.com/typography/cleartype/truetypecleartype.aspx
707    */
708 /* #define TT_CONFIG_OPTION_SUBPIXEL_HINTING  1         */
709 #define TT_CONFIG_OPTION_SUBPIXEL_HINTING  2
710 /* #define TT_CONFIG_OPTION_SUBPIXEL_HINTING  ( 1 | 2 ) */
711 
712 
713   /**************************************************************************
714    *
715    * Define `TT_CONFIG_OPTION_COMPONENT_OFFSET_SCALED` to compile the
716    * TrueType glyph loader to use Apple's definition of how to handle
717    * component offsets in composite glyphs.
718    *
719    * Apple and MS disagree on the default behavior of component offsets in
720    * composites.  Apple says that they should be scaled by the scaling
721    * factors in the transformation matrix (roughly, it's more complex) while
722    * MS says they should not.  OpenType defines two bits in the composite
723    * flags array which can be used to disambiguate, but old fonts will not
724    * have them.
725    *
726    *   https://www.microsoft.com/typography/otspec/glyf.htm
727    *   https://developer.apple.com/fonts/TrueType-Reference-Manual/RM06/Chap6glyf.html
728    */
729 #undef TT_CONFIG_OPTION_COMPONENT_OFFSET_SCALED
730 
731 
732   /**************************************************************************
733    *
734    * Define `TT_CONFIG_OPTION_GX_VAR_SUPPORT` if you want to include support
735    * for Apple's distortable font technology ('fvar', 'gvar', 'cvar', and
736    * 'avar' tables).  Tagged 'Font Variations', this is now part of OpenType
737    * also.  This has many similarities to Type~1 Multiple Masters support.
738    */
739 #define TT_CONFIG_OPTION_GX_VAR_SUPPORT
740 
741 
742   /**************************************************************************
743    *
744    * Define `TT_CONFIG_OPTION_BDF` if you want to include support for an
745    * embedded 'BDF~' table within SFNT-based bitmap formats.
746    */
747 #define TT_CONFIG_OPTION_BDF
748 
749 
750   /**************************************************************************
751    *
752    * Option `TT_CONFIG_OPTION_MAX_RUNNABLE_OPCODES` controls the maximum
753    * number of bytecode instructions executed for a single run of the
754    * bytecode interpreter, needed to prevent infinite loops.  You don't want
755    * to change this except for very special situations (e.g., making a
756    * library fuzzer spend less time to handle broken fonts).
757    *
758    * It is not expected that this value is ever modified by a configuring
759    * script; instead, it gets surrounded with `#ifndef ... #endif` so that
760    * the value can be set as a preprocessor option on the compiler's command
761    * line.
762    */
763 #ifndef TT_CONFIG_OPTION_MAX_RUNNABLE_OPCODES
764 #define TT_CONFIG_OPTION_MAX_RUNNABLE_OPCODES  1000000L
765 #endif
766 
767 
768   /*************************************************************************/
769   /*************************************************************************/
770   /****                                                                 ****/
771   /****      T Y P E 1   D R I V E R    C O N F I G U R A T I O N       ****/
772   /****                                                                 ****/
773   /*************************************************************************/
774   /*************************************************************************/
775 
776 
777   /**************************************************************************
778    *
779    * `T1_MAX_DICT_DEPTH` is the maximum depth of nest dictionaries and arrays
780    * in the Type~1 stream (see `t1load.c`).  A minimum of~4 is required.
781    */
782 #define T1_MAX_DICT_DEPTH  5
783 
784 
785   /**************************************************************************
786    *
787    * `T1_MAX_SUBRS_CALLS` details the maximum number of nested sub-routine
788    * calls during glyph loading.
789    */
790 #define T1_MAX_SUBRS_CALLS  16
791 
792 
793   /**************************************************************************
794    *
795    * `T1_MAX_CHARSTRING_OPERANDS` is the charstring stack's capacity.  A
796    * minimum of~16 is required.
797    *
798    * The Chinese font 'MingTiEG-Medium' (covering the CNS 11643 character
799    * set) needs 256.
800    */
801 #define T1_MAX_CHARSTRINGS_OPERANDS  256
802 
803 
804   /**************************************************************************
805    *
806    * Define this configuration macro if you want to prevent the compilation
807    * of the 't1afm' module, which is in charge of reading Type~1 AFM files
808    * into an existing face.  Note that if set, the Type~1 driver will be
809    * unable to produce kerning distances.
810    */
811 #undef T1_CONFIG_OPTION_NO_AFM
812 
813 
814   /**************************************************************************
815    *
816    * Define this configuration macro if you want to prevent the compilation
817    * of the Multiple Masters font support in the Type~1 driver.
818    */
819 #undef T1_CONFIG_OPTION_NO_MM_SUPPORT
820 
821 
822   /**************************************************************************
823    *
824    * `T1_CONFIG_OPTION_OLD_ENGINE` controls whether the pre-Adobe Type~1
825    * engine gets compiled into FreeType.  If defined, it is possible to
826    * switch between the two engines using the `hinting-engine` property of
827    * the 'type1' driver module.
828    */
829 /* #define T1_CONFIG_OPTION_OLD_ENGINE */
830 
831 
832   /*************************************************************************/
833   /*************************************************************************/
834   /****                                                                 ****/
835   /****         C F F   D R I V E R    C O N F I G U R A T I O N        ****/
836   /****                                                                 ****/
837   /*************************************************************************/
838   /*************************************************************************/
839 
840 
841   /**************************************************************************
842    *
843    * Using `CFF_CONFIG_OPTION_DARKENING_PARAMETER_{X,Y}{1,2,3,4}` it is
844    * possible to set up the default values of the four control points that
845    * define the stem darkening behaviour of the (new) CFF engine.  For more
846    * details please read the documentation of the `darkening-parameters`
847    * property (file `ftdriver.h`), which allows the control at run-time.
848    *
849    * Do **not** undefine these macros!
850    */
851 #define CFF_CONFIG_OPTION_DARKENING_PARAMETER_X1   500
852 #define CFF_CONFIG_OPTION_DARKENING_PARAMETER_Y1   400
853 
854 #define CFF_CONFIG_OPTION_DARKENING_PARAMETER_X2  1000
855 #define CFF_CONFIG_OPTION_DARKENING_PARAMETER_Y2   275
856 
857 #define CFF_CONFIG_OPTION_DARKENING_PARAMETER_X3  1667
858 #define CFF_CONFIG_OPTION_DARKENING_PARAMETER_Y3   275
859 
860 #define CFF_CONFIG_OPTION_DARKENING_PARAMETER_X4  2333
861 #define CFF_CONFIG_OPTION_DARKENING_PARAMETER_Y4     0
862 
863 
864   /**************************************************************************
865    *
866    * `CFF_CONFIG_OPTION_OLD_ENGINE` controls whether the pre-Adobe CFF engine
867    * gets compiled into FreeType.  If defined, it is possible to switch
868    * between the two engines using the `hinting-engine` property of the 'cff'
869    * driver module.
870    */
871 /* #define CFF_CONFIG_OPTION_OLD_ENGINE */
872 
873 
874   /*************************************************************************/
875   /*************************************************************************/
876   /****                                                                 ****/
877   /****         P C F   D R I V E R    C O N F I G U R A T I O N        ****/
878   /****                                                                 ****/
879   /*************************************************************************/
880   /*************************************************************************/
881 
882 
883   /**************************************************************************
884    *
885    * There are many PCF fonts just called 'Fixed' which look completely
886    * different, and which have nothing to do with each other.  When selecting
887    * 'Fixed' in KDE or Gnome one gets results that appear rather random, the
888    * style changes often if one changes the size and one cannot select some
889    * fonts at all.  This option makes the 'pcf' module prepend the foundry
890    * name (plus a space) to the family name.
891    *
892    * We also check whether we have 'wide' characters; all put together, we
893    * get family names like 'Sony Fixed' or 'Misc Fixed Wide'.
894    *
895    * If this option is activated, it can be controlled with the
896    * `no-long-family-names` property of the 'pcf' driver module.
897    */
898 /* #define PCF_CONFIG_OPTION_LONG_FAMILY_NAMES */
899 
900 
901   /*************************************************************************/
902   /*************************************************************************/
903   /****                                                                 ****/
904   /****    A U T O F I T   M O D U L E    C O N F I G U R A T I O N     ****/
905   /****                                                                 ****/
906   /*************************************************************************/
907   /*************************************************************************/
908 
909 
910   /**************************************************************************
911    *
912    * Compile 'autofit' module with CJK (Chinese, Japanese, Korean) script
913    * support.
914    */
915 #define AF_CONFIG_OPTION_CJK
916 
917 
918   /**************************************************************************
919    *
920    * Compile 'autofit' module with fallback Indic script support, covering
921    * some scripts that the 'latin' submodule of the 'autofit' module doesn't
922    * (yet) handle.  Currently, this needs option `AF_CONFIG_OPTION_CJK`.
923    */
924 #ifdef AF_CONFIG_OPTION_CJK
925 #define AF_CONFIG_OPTION_INDIC
926 #endif
927 
928 
929   /**************************************************************************
930    *
931    * Use TrueType-like size metrics for 'light' auto-hinting.
932    *
933    * It is strongly recommended to avoid this option, which exists only to
934    * help some legacy applications retain its appearance and behaviour with
935    * respect to auto-hinted TrueType fonts.
936    *
937    * The very reason this option exists at all are GNU/Linux distributions
938    * like Fedora that did not un-patch the following change (which was
939    * present in FreeType between versions 2.4.6 and 2.7.1, inclusive).
940    *
941    * ```
942    *   2011-07-16  Steven Chu  <steven.f.chu@gmail.com>
943    *
944    *     [truetype] Fix metrics on size request for scalable fonts.
945    * ```
946    *
947    * This problematic commit is now reverted (more or less).
948    */
949 /* #define AF_CONFIG_OPTION_TT_SIZE_METRICS */
950 
951   /* */
952 
953 
954   /*
955    * This macro is obsolete.  Support has been removed in FreeType version
956    * 2.5.
957    */
958 /* #define FT_CONFIG_OPTION_OLD_INTERNALS */
959 
960 
961   /*
962    * The next three macros are defined if native TrueType hinting is
963    * requested by the definitions above.  Don't change this.
964    */
965 #ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
966 #define  TT_USE_BYTECODE_INTERPRETER
967 
968 #ifdef TT_CONFIG_OPTION_SUBPIXEL_HINTING
969 #if TT_CONFIG_OPTION_SUBPIXEL_HINTING & 1
970 #define  TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY
971 #endif
972 
973 #if TT_CONFIG_OPTION_SUBPIXEL_HINTING & 2
974 #define  TT_SUPPORT_SUBPIXEL_HINTING_MINIMAL
975 #endif
976 #endif
977 #endif
978 
979 
980   /*
981    * The TT_SUPPORT_COLRV1 macro is defined to indicate to clients that this
982    * version of FreeType has support for 'COLR' v1 API.  This definition is
983    * useful to FreeType clients that want to build in support for 'COLR' v1
984    * depending on a tip-of-tree checkout before it is officially released in
985    * FreeType, and while the feature cannot yet be tested against using
986    * version macros.  Don't change this macro.  This may be removed once the
987    * feature is in a FreeType release version and version macros can be used
988    * to test for availability.
989    */
990 #ifdef TT_CONFIG_OPTION_COLOR_LAYERS
991 #define  TT_SUPPORT_COLRV1
992 #endif
993 
994 
995   /*
996    * Check CFF darkening parameters.  The checks are the same as in function
997    * `cff_property_set` in file `cffdrivr.c`.
998    */
999 #if CFF_CONFIG_OPTION_DARKENING_PARAMETER_X1 < 0   || \
1000     CFF_CONFIG_OPTION_DARKENING_PARAMETER_X2 < 0   || \
1001     CFF_CONFIG_OPTION_DARKENING_PARAMETER_X3 < 0   || \
1002     CFF_CONFIG_OPTION_DARKENING_PARAMETER_X4 < 0   || \
1003                                                       \
1004     CFF_CONFIG_OPTION_DARKENING_PARAMETER_Y1 < 0   || \
1005     CFF_CONFIG_OPTION_DARKENING_PARAMETER_Y2 < 0   || \
1006     CFF_CONFIG_OPTION_DARKENING_PARAMETER_Y3 < 0   || \
1007     CFF_CONFIG_OPTION_DARKENING_PARAMETER_Y4 < 0   || \
1008                                                       \
1009     CFF_CONFIG_OPTION_DARKENING_PARAMETER_X1 >        \
1010       CFF_CONFIG_OPTION_DARKENING_PARAMETER_X2     || \
1011     CFF_CONFIG_OPTION_DARKENING_PARAMETER_X2 >        \
1012       CFF_CONFIG_OPTION_DARKENING_PARAMETER_X3     || \
1013     CFF_CONFIG_OPTION_DARKENING_PARAMETER_X3 >        \
1014       CFF_CONFIG_OPTION_DARKENING_PARAMETER_X4     || \
1015                                                       \
1016     CFF_CONFIG_OPTION_DARKENING_PARAMETER_Y1 > 500 || \
1017     CFF_CONFIG_OPTION_DARKENING_PARAMETER_Y2 > 500 || \
1018     CFF_CONFIG_OPTION_DARKENING_PARAMETER_Y3 > 500 || \
1019     CFF_CONFIG_OPTION_DARKENING_PARAMETER_Y4 > 500
1020 #error "Invalid CFF darkening parameters!"
1021 #endif
1022 
1023 
1024 FT_END_HEADER
1025 
1026 #endif /* FTOPTION_H_ */
1027 
1028 
1029 /* END */
1030