/* */
/* User-selectable configuration macros (specification only). */
/* */
-/* Copyright 1996-2015 by */
+/* Copyright 1996-2016 by */
/* David Turner, Robert Wilhelm, and Werner Lemberg. */
/* */
/* This file is part of the FreeType project, and may only be used, */
/***************************************************************************/
-#ifndef __FTOPTION_H__
-#define __FTOPTION_H__
+#ifndef FTOPTION_H_
+#define FTOPTION_H_
#include <ft2build.h>
/* that are statically linked to the library at compile time. By */
/* default, this file is <freetype/config/ftmodule.h>. */
/* */
- /* We highly recommend using the third method whenever possible. */
+ /* We highly recommend using the third method whenever possible. */
/* */
/*************************************************************************/
/*************************************************************************/
+ /*************************************************************************/
+ /* */
+ /* If you enable this configuration option, FreeType recognizes an */
+ /* environment variable called `FREETYPE_PROPERTIES', which can be used */
+ /* to control the various font drivers and modules. The controllable */
+ /* properties are listed in the section `Controlling FreeType Modules' */
+ /* in the reference's table of contents; currently there are properties */
+ /* for the auto-hinter (file `ftautoh.h'), CFF (file `ftcffdrv.h'), and */
+ /* TrueType (file `ftttdrv.h'). */
+ /* */
+ /* `FREETYPE_PROPERTIES' has the following syntax form (broken here into */
+ /* multiple lines for better readability). */
+ /* */
+ /* <optional whitespace> */
+ /* <module-name1> ':' */
+ /* <property-name1> '=' <property-value1> */
+ /* <whitespace> */
+ /* <module-name2> ':' */
+ /* <property-name2> '=' <property-value2> */
+ /* ... */
+ /* */
+ /* Example: */
+ /* */
+ /* FREETYPE_PROPERTIES=truetype:interpreter-version=35 \ */
+ /* cff:no-stem-darkening=1 \ */
+ /* autofitter:warping=1 */
+ /* */
+#define FT_CONFIG_OPTION_ENVIRONMENT_PROPERTIES
+
+
/*************************************************************************/
/* */
/* Uncomment the line below if you want to activate sub-pixel rendering */
/*************************************************************************/
/* */
/* Define TT_CONFIG_OPTION_SUBPIXEL_HINTING if you want to compile */
- /* EXPERIMENTAL subpixel hinting support into the TrueType driver. This */
- /* replaces the native TrueType hinting mechanism when anything but */
- /* FT_RENDER_MODE_MONO is requested. */
- /* */
- /* Enabling this causes the TrueType driver to ignore instructions under */
- /* certain conditions. This is done in accordance with the guide here, */
- /* with some minor differences: */
+ /* subpixel hinting support into the TrueType driver. This modifies the */
+ /* TrueType hinting mechanism when anything but FT_RENDER_MODE_MONO is */
+ /* requested. */
/* */
- /* http://www.microsoft.com/typography/cleartype/truetypecleartype.aspx */
+ /* In particular, it modifies the bytecode interpreter to interpret (or */
+ /* not) instructions in a certain way so that all TrueType fonts look */
+ /* like they do in a Windows ClearType (DirectWrite) environment. See */
+ /* [1] for a technical overview on what this means. See `ttinterp.h' */
+ /* for more details on the LEAN option. */
/* */
- /* By undefining this, you only compile the code necessary to hint */
- /* TrueType glyphs with native TT hinting. */
+ /* There are three options. */
/* */
- /* This option requires TT_CONFIG_OPTION_BYTECODE_INTERPRETER to be */
- /* defined. */
+ /* 1. This option is associated with the `Infinality' moniker. */
+ /* Contributed by an individual nicknamed Infinality with the goal of */
+ /* making TrueType fonts render better than on Windows. A high */
+ /* amount of configurability and flexibility, down to rules for */
+ /* single glyphs in fonts, but also very slow. Its experimental and */
+ /* slow nature and the original developer losing interest meant that */
+ /* this option was never enabled in default builds. */
/* */
-/* #define TT_CONFIG_OPTION_SUBPIXEL_HINTING */
-
-
- /*************************************************************************/
+ /* 2. The new default mode for the TrueType driver. The Infinality code */
+ /* base was stripped to the bare minimum and all configurability */
+ /* removed in the name of speed and simplicity. The configurability */
+ /* was mainly aimed at legacy fonts like Arial, Times New Roman, or */
+ /* Courier. Legacy fonts are fonts that modify vertical stems to */
+ /* achieve clean black-and-white bitmaps. The new mode focuses on */
+ /* applying a minimal set of rules to all fonts indiscriminately so */
+ /* that modern and web fonts render well while legacy fonts render */
+ /* okay. */
/* */
- /* If you define TT_CONFIG_OPTION_UNPATENTED_HINTING, a special version */
- /* of the TrueType bytecode interpreter is used that doesn't implement */
- /* any of the patented opcodes and algorithms. The patents related to */
- /* TrueType hinting have expired worldwide since May 2010; this option */
- /* is now deprecated. */
+ /* 3. Compile both. */
/* */
- /* Note that the TT_CONFIG_OPTION_UNPATENTED_HINTING macro is *ignored* */
- /* if you define TT_CONFIG_OPTION_BYTECODE_INTERPRETER; in other words, */
- /* either define TT_CONFIG_OPTION_BYTECODE_INTERPRETER or */
- /* TT_CONFIG_OPTION_UNPATENTED_HINTING but not both at the same time. */
+ /* By undefining these, you get rendering behavior like on Windows */
+ /* without ClearType, i.e., Windows XP without ClearType enabled and */
+ /* Win9x (interpreter version v35). Or not, depending on how much */
+ /* hinting blood and testing tears the font designer put into a given */
+ /* font. If you define one or both subpixel hinting options, you can */
+ /* switch between between v35 and the ones you define. */
/* */
- /* This macro is only useful for a small number of font files (mostly */
- /* for Asian scripts) that require bytecode interpretation to properly */
- /* load glyphs. For all other fonts, this produces unpleasant results, */
- /* thus the unpatented interpreter is never used to load glyphs from */
- /* TrueType fonts unless one of the following two options is used. */
+ /* This option requires TT_CONFIG_OPTION_BYTECODE_INTERPRETER to be */
+ /* defined. */
/* */
- /* - The unpatented interpreter is explicitly activated by the user */
- /* through the FT_PARAM_TAG_UNPATENTED_HINTING parameter tag */
- /* when opening the FT_Face. */
+ /* [1] http://www.microsoft.com/typography/cleartype/truetypecleartype.aspx */
/* */
- /* - FreeType detects that the FT_Face corresponds to one of the */
- /* `trick' fonts (e.g., `Mingliu') it knows about. The font engine */
- /* contains a hard-coded list of font names and other matching */
- /* parameters (see function `tt_face_init' in file */
- /* `src/truetype/ttobjs.c'). */
- /* */
- /* Here a sample code snippet for using FT_PARAM_TAG_UNPATENTED_HINTING. */
- /* */
- /* { */
- /* FT_Parameter parameter; */
- /* FT_Open_Args open_args; */
- /* */
- /* */
- /* parameter.tag = FT_PARAM_TAG_UNPATENTED_HINTING; */
- /* */
- /* open_args.flags = FT_OPEN_PATHNAME | FT_OPEN_PARAMS; */
- /* open_args.pathname = my_font_pathname; */
- /* open_args.num_params = 1; */
- /* open_args.params = ¶meter; */
- /* */
- /* error = FT_Open_Face( library, &open_args, index, &face ); */
- /* ... */
- /* } */
- /* */
-/* #define TT_CONFIG_OPTION_UNPATENTED_HINTING */
+/* #define TT_CONFIG_OPTION_SUBPIXEL_HINTING 1 */
+#define TT_CONFIG_OPTION_SUBPIXEL_HINTING 2
+/* #define TT_CONFIG_OPTION_SUBPIXEL_HINTING ( 1 | 2 ) */
/*************************************************************************/
/*
- * This macro is defined if either unpatented or native TrueType
- * hinting is requested by the definitions above.
+ * This macro is defined if native TrueType hinting is requested by the
+ * definitions above.
*/
#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
#define TT_USE_BYTECODE_INTERPRETER
-#undef TT_CONFIG_OPTION_UNPATENTED_HINTING
-#elif defined TT_CONFIG_OPTION_UNPATENTED_HINTING
-#define TT_USE_BYTECODE_INTERPRETER
+
+#if TT_CONFIG_OPTION_SUBPIXEL_HINTING & 1
+#define TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY
+#endif
+
+#if TT_CONFIG_OPTION_SUBPIXEL_HINTING & 2
+#define TT_SUPPORT_SUBPIXEL_HINTING_MINIMAL
+#endif
#endif
FT_END_HEADER
-#endif /* __FTOPTION_H__ */
+#endif /* FTOPTION_H_ */
/* END */
projects / platform / upstream / libSkiaSharp.git / commitdiff