44/* */
55/* User-selectable configuration macros (specification only). */
66/* */
7- /* Copyright 1996-2015 by */
7+ /* Copyright 1996-2016 by */
88/* David Turner, Robert Wilhelm, and Werner Lemberg. */
99/* */
1010/* This file is part of the FreeType project, and may only be used, */
1616/***************************************************************************/
1717
1818
19- #ifndef __FTOPTION_H__
20- #define __FTOPTION_H__
19+ #ifndef FTOPTION_H_
20+ #define FTOPTION_H_
2121
2222
2323#include <ft2build.h>
@@ -75,6 +75,36 @@ FT_BEGIN_HEADER
7575 /*************************************************************************/
7676
7777
78+ /*************************************************************************/
79+ /* */
80+ /* If you enable this configuration option, FreeType recognizes an */
81+ /* environment variable called `FREETYPE_PROPERTIES', which can be used */
82+ /* to control the various font drivers and modules. The controllable */
83+ /* properties are listed in the section `Controlling FreeType Modules' */
84+ /* in the reference's table of contents; currently there are properties */
85+ /* for the auto-hinter (file `ftautoh.h'), CFF (file `ftcffdrv.h'), and */
86+ /* TrueType (file `ftttdrv.h'). */
87+ /* */
88+ /* `FREETYPE_PROPERTIES' has the following syntax form (broken here into */
89+ /* multiple lines for better readability). */
90+ /* */
91+ /* <optional whitespace> */
92+ /* <module-name1> ':' */
93+ /* <property-name1> '=' <property-value1> */
94+ /* <whitespace> */
95+ /* <module-name2> ':' */
96+ /* <property-name2> '=' <property-value2> */
97+ /* ... */
98+ /* */
99+ /* Example: */
100+ /* */
101+ /* FREETYPE_PROPERTIES=truetype:interpreter-version=35 \ */
102+ /* cff:no-stem-darkening=1 \ */
103+ /* autofitter:warping=1 */
104+ /* */
105+ /* #define FT_CONFIG_OPTION_ENVIRONMENT_PROPERTIES */
106+
107+
78108 /*************************************************************************/
79109 /* */
80110 /* Uncomment the line below if you want to activate sub-pixel rendering */
@@ -492,7 +522,21 @@ FT_BEGIN_HEADER
492522 /* code will be used. */
493523 /* */
494524 /* Setting this macro is needed for systems that prohibit address */
495- /* fixups, such as BREW. */
525+ /* fixups, such as BREW. [Note that standard compilers like gcc or */
526+ /* clang handle PIC generation automatically; you don't have to set */
527+ /* FT_CONFIG_OPTION_PIC, which is only necessary for very special */
528+ /* compilers.] */
529+ /* */
530+ /* Note that FT_CONFIG_OPTION_PIC support is not available for all */
531+ /* modules (see `modules.cfg' for a complete list). For building with */
532+ /* FT_CONFIG_OPTION_PIC support, do the following. */
533+ /* */
534+ /* 0. Clone the repository. */
535+ /* 1. Define FT_CONFIG_OPTION_PIC. */
536+ /* 2. Remove all subdirectories in `src' that don't have */
537+ /* FT_CONFIG_OPTION_PIC support. */
538+ /* 3. Comment out the corresponding modules in `modules.cfg'. */
539+ /* 4. Compile. */
496540 /* */
497541/* #define FT_CONFIG_OPTION_PIC */
498542
@@ -586,73 +630,53 @@ FT_BEGIN_HEADER
586630 /*************************************************************************/
587631 /* */
588632 /* Define TT_CONFIG_OPTION_SUBPIXEL_HINTING if you want to compile */
589- /* EXPERIMENTAL subpixel hinting support into the TrueType driver. This */
590- /* replaces the native TrueType hinting mechanism when anything but */
591- /* FT_RENDER_MODE_MONO is requested. */
592- /* */
593- /* Enabling this causes the TrueType driver to ignore instructions under */
594- /* certain conditions. This is done in accordance with the guide here, */
595- /* with some minor differences: */
633+ /* subpixel hinting support into the TrueType driver. This modifies the */
634+ /* TrueType hinting mechanism when anything but FT_RENDER_MODE_MONO is */
635+ /* requested. */
596636 /* */
597- /* http://www.microsoft.com/typography/cleartype/truetypecleartype.aspx */
637+ /* In particular, it modifies the bytecode interpreter to interpret (or */
638+ /* not) instructions in a certain way so that all TrueType fonts look */
639+ /* like they do in a Windows ClearType (DirectWrite) environment. See */
640+ /* [1] for a technical overview on what this means. See `ttinterp.h' */
641+ /* for more details on the LEAN option. */
598642 /* */
599- /* By undefining this, you only compile the code necessary to hint */
600- /* TrueType glyphs with native TT hinting. */
643+ /* There are three options. */
601644 /* */
602- /* This option requires TT_CONFIG_OPTION_BYTECODE_INTERPRETER to be */
603- /* defined. */
645+ /* 1. This option is associated with the `Infinality' moniker. */
646+ /* Contributed by an individual nicknamed Infinality with the goal of */
647+ /* making TrueType fonts render better than on Windows. A high */
648+ /* amount of configurability and flexibility, down to rules for */
649+ /* single glyphs in fonts, but also very slow. Its experimental and */
650+ /* slow nature and the original developer losing interest meant that */
651+ /* this option was never enabled in default builds. */
604652 /* */
605- /* #define TT_CONFIG_OPTION_SUBPIXEL_HINTING */
606-
607-
608- /*************************************************************************/
653+ /* 2. The new default mode for the TrueType driver. The Infinality code */
654+ /* base was stripped to the bare minimum and all configurability */
655+ /* removed in the name of speed and simplicity. The configurability */
656+ /* was mainly aimed at legacy fonts like Arial, Times New Roman, or */
657+ /* Courier. Legacy fonts are fonts that modify vertical stems to */
658+ /* achieve clean black-and-white bitmaps. The new mode focuses on */
659+ /* applying a minimal set of rules to all fonts indiscriminately so */
660+ /* that modern and web fonts render well while legacy fonts render */
661+ /* okay. */
609662 /* */
610- /* If you define TT_CONFIG_OPTION_UNPATENTED_HINTING, a special version */
611- /* of the TrueType bytecode interpreter is used that doesn't implement */
612- /* any of the patented opcodes and algorithms. The patents related to */
613- /* TrueType hinting have expired worldwide since May 2010; this option */
614- /* is now deprecated. */
663+ /* 3. Compile both. */
615664 /* */
616- /* Note that the TT_CONFIG_OPTION_UNPATENTED_HINTING macro is *ignored* */
617- /* if you define TT_CONFIG_OPTION_BYTECODE_INTERPRETER; in other words, */
618- /* either define TT_CONFIG_OPTION_BYTECODE_INTERPRETER or */
619- /* TT_CONFIG_OPTION_UNPATENTED_HINTING but not both at the same time. */
665+ /* By undefining these, you get rendering behavior like on Windows */
666+ /* without ClearType, i.e., Windows XP without ClearType enabled and */
667+ /* Win9x (interpreter version v35). Or not, depending on how much */
668+ /* hinting blood and testing tears the font designer put into a given */
669+ /* font. If you define one or both subpixel hinting options, you can */
670+ /* switch between between v35 and the ones you define. */
620671 /* */
621- /* This macro is only useful for a small number of font files (mostly */
622- /* for Asian scripts) that require bytecode interpretation to properly */
623- /* load glyphs. For all other fonts, this produces unpleasant results, */
624- /* thus the unpatented interpreter is never used to load glyphs from */
625- /* TrueType fonts unless one of the following two options is used. */
672+ /* This option requires TT_CONFIG_OPTION_BYTECODE_INTERPRETER to be */
673+ /* defined. */
626674 /* */
627- /* - The unpatented interpreter is explicitly activated by the user */
628- /* through the FT_PARAM_TAG_UNPATENTED_HINTING parameter tag */
629- /* when opening the FT_Face. */
675+ /* [1] http://www.microsoft.com/typography/cleartype/truetypecleartype.aspx */
630676 /* */
631- /* - FreeType detects that the FT_Face corresponds to one of the */
632- /* `trick' fonts (e.g., `Mingliu') it knows about. The font engine */
633- /* contains a hard-coded list of font names and other matching */
634- /* parameters (see function `tt_face_init' in file */
635- /* `src/truetype/ttobjs.c'). */
636- /* */
637- /* Here a sample code snippet for using FT_PARAM_TAG_UNPATENTED_HINTING. */
638- /* */
639- /* { */
640- /* FT_Parameter parameter; */
641- /* FT_Open_Args open_args; */
642- /* */
643- /* */
644- /* parameter.tag = FT_PARAM_TAG_UNPATENTED_HINTING; */
645- /* */
646- /* open_args.flags = FT_OPEN_PATHNAME | FT_OPEN_PARAMS; */
647- /* open_args.pathname = my_font_pathname; */
648- /* open_args.num_params = 1; */
649- /* open_args.params = ¶meter; */
650- /* */
651- /* error = FT_Open_Face( library, &open_args, index, &face ); */
652- /* ... */
653- /* } */
654- /* */
655- /* #define TT_CONFIG_OPTION_UNPATENTED_HINTING */
677+ /* #define TT_CONFIG_OPTION_SUBPIXEL_HINTING 1 */
678+ /* #define TT_CONFIG_OPTION_SUBPIXEL_HINTING 2 */
679+ /* #define TT_CONFIG_OPTION_SUBPIXEL_HINTING ( 1 | 2 ) */
656680
657681
658682 /*************************************************************************/
@@ -843,7 +867,7 @@ FT_BEGIN_HEADER
843867 /* `warping' property of the auto-hinter (see file `ftautoh.h' for more */
844868 /* information; by default it is switched off). */
845869 /* */
846- /* #define AF_CONFIG_OPTION_USE_WARPER */
870+ #define AF_CONFIG_OPTION_USE_WARPER
847871
848872 /* */
849873
@@ -856,14 +880,19 @@ FT_BEGIN_HEADER
856880
857881
858882 /*
859- * This macro is defined if either unpatented or native TrueType
860- * hinting is requested by the definitions above.
883+ * This macro is defined if native TrueType hinting is requested by the
884+ * definitions above.
861885 */
862886#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
863887#define TT_USE_BYTECODE_INTERPRETER
864- #undef TT_CONFIG_OPTION_UNPATENTED_HINTING
865- #elif defined TT_CONFIG_OPTION_UNPATENTED_HINTING
866- #define TT_USE_BYTECODE_INTERPRETER
888+
889+ #if TT_CONFIG_OPTION_SUBPIXEL_HINTING & 1
890+ #define TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY
891+ #endif
892+
893+ #if TT_CONFIG_OPTION_SUBPIXEL_HINTING & 2
894+ #define TT_SUPPORT_SUBPIXEL_HINTING_MINIMAL
895+ #endif
867896#endif
868897
869898
@@ -898,7 +927,7 @@ FT_BEGIN_HEADER
898927FT_END_HEADER
899928
900929
901- #endif /* __FTOPTION_H__ */
930+ #endif /* FTOPTION_H_ */
902931
903932
904933/* END */
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