1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/modules/freetype2/include/ftautoh.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,402 @@
1.4 +/***************************************************************************/
1.5 +/* */
1.6 +/* ftautoh.h */
1.7 +/* */
1.8 +/* FreeType API for controlling the auto-hinter (specification only). */
1.9 +/* */
1.10 +/* Copyright 2012, 2013 by */
1.11 +/* David Turner, Robert Wilhelm, and Werner Lemberg. */
1.12 +/* */
1.13 +/* This file is part of the FreeType project, and may only be used, */
1.14 +/* modified, and distributed under the terms of the FreeType project */
1.15 +/* license, LICENSE.TXT. By continuing to use, modify, or distribute */
1.16 +/* this file you indicate that you have read the license and */
1.17 +/* understand and accept it fully. */
1.18 +/* */
1.19 +/***************************************************************************/
1.20 +
1.21 +
1.22 +#ifndef __FTAUTOH_H__
1.23 +#define __FTAUTOH_H__
1.24 +
1.25 +#include <ft2build.h>
1.26 +#include FT_FREETYPE_H
1.27 +
1.28 +#ifdef FREETYPE_H
1.29 +#error "freetype.h of FreeType 1 has been loaded!"
1.30 +#error "Please fix the directory search order for header files"
1.31 +#error "so that freetype.h of FreeType 2 is found first."
1.32 +#endif
1.33 +
1.34 +
1.35 +FT_BEGIN_HEADER
1.36 +
1.37 +
1.38 + /**************************************************************************
1.39 + *
1.40 + * @section:
1.41 + * auto_hinter
1.42 + *
1.43 + * @title:
1.44 + * The auto-hinter
1.45 + *
1.46 + * @abstract:
1.47 + * Controlling the auto-hinting module.
1.48 + *
1.49 + * @description:
1.50 + * While FreeType's auto-hinter doesn't expose API functions by itself,
1.51 + * it is possible to control its behaviour with @FT_Property_Set and
1.52 + * @FT_Property_Get. The following lists the available properties
1.53 + * together with the necessary macros and structures.
1.54 + *
1.55 + * Note that the auto-hinter's module name is `autofitter' for
1.56 + * historical reasons.
1.57 + *
1.58 + */
1.59 +
1.60 +
1.61 + /**************************************************************************
1.62 + *
1.63 + * @property:
1.64 + * glyph-to-script-map
1.65 + *
1.66 + * @description:
1.67 + * *Experimental* *only*
1.68 + *
1.69 + * The auto-hinter provides various script modules to hint glyphs.
1.70 + * Examples of supported scripts are Latin or CJK. Before a glyph is
1.71 + * auto-hinted, the Unicode character map of the font gets examined, and
1.72 + * the script is then determined based on Unicode character ranges, see
1.73 + * below.
1.74 + *
1.75 + * OpenType fonts, however, often provide much more glyphs than
1.76 + * character codes (small caps, superscripts, ligatures, swashes, etc.),
1.77 + * to be controlled by so-called `features'. Handling OpenType features
1.78 + * can be quite complicated and thus needs a separate library on top of
1.79 + * FreeType.
1.80 + *
1.81 + * The mapping between glyph indices and scripts (in the auto-hinter
1.82 + * sense, see the @FT_AUTOHINTER_SCRIPT_XXX values) is stored as an
1.83 + * array with `num_glyphs' elements, as found in the font's @FT_Face
1.84 + * structure. The `glyph-to-script-map' property returns a pointer to
1.85 + * this array, which can be modified as needed. Note that the
1.86 + * modification should happen before the first glyph gets processed by
1.87 + * the auto-hinter so that the global analysis of the font shapes
1.88 + * actually uses the modified mapping.
1.89 + *
1.90 + * The following example code demonstrates how to access it (omitting
1.91 + * the error handling).
1.92 + *
1.93 + * {
1.94 + * FT_Library library;
1.95 + * FT_Face face;
1.96 + * FT_Prop_GlyphToScriptMap prop;
1.97 + *
1.98 + *
1.99 + * FT_Init_FreeType( &library );
1.100 + * FT_New_Face( library, "foo.ttf", 0, &face );
1.101 + *
1.102 + * prop.face = face;
1.103 + *
1.104 + * FT_Property_Get( library, "autofitter",
1.105 + * "glyph-to-script-map", &prop );
1.106 + *
1.107 + * // adjust `prop.map' as needed right here
1.108 + *
1.109 + * FT_Load_Glyph( face, ..., FT_LOAD_FORCE_AUTOHINT );
1.110 + * }
1.111 + *
1.112 + */
1.113 +
1.114 +
1.115 + /**************************************************************************
1.116 + *
1.117 + * @enum:
1.118 + * FT_AUTOHINTER_SCRIPT_XXX
1.119 + *
1.120 + * @description:
1.121 + * *Experimental* *only*
1.122 + *
1.123 + * A list of constants used for the @glyph-to-script-map property to
1.124 + * specify the script submodule the auto-hinter should use for hinting a
1.125 + * particular glyph.
1.126 + *
1.127 + * @values:
1.128 + * FT_AUTOHINTER_SCRIPT_NONE ::
1.129 + * Don't auto-hint this glyph.
1.130 + *
1.131 + * FT_AUTOHINTER_SCRIPT_LATIN ::
1.132 + * Apply the latin auto-hinter. For the auto-hinter, `latin' is a
1.133 + * very broad term, including Cyrillic and Greek also since characters
1.134 + * from those scripts share the same design constraints.
1.135 + *
1.136 + * By default, characters from the following Unicode ranges are
1.137 + * assigned to this submodule.
1.138 + *
1.139 + * {
1.140 + * U+0020 - U+007F // Basic Latin (no control characters)
1.141 + * U+00A0 - U+00FF // Latin-1 Supplement (no control characters)
1.142 + * U+0100 - U+017F // Latin Extended-A
1.143 + * U+0180 - U+024F // Latin Extended-B
1.144 + * U+0250 - U+02AF // IPA Extensions
1.145 + * U+02B0 - U+02FF // Spacing Modifier Letters
1.146 + * U+0300 - U+036F // Combining Diacritical Marks
1.147 + * U+0370 - U+03FF // Greek and Coptic
1.148 + * U+0400 - U+04FF // Cyrillic
1.149 + * U+0500 - U+052F // Cyrillic Supplement
1.150 + * U+1D00 - U+1D7F // Phonetic Extensions
1.151 + * U+1D80 - U+1DBF // Phonetic Extensions Supplement
1.152 + * U+1DC0 - U+1DFF // Combining Diacritical Marks Supplement
1.153 + * U+1E00 - U+1EFF // Latin Extended Additional
1.154 + * U+1F00 - U+1FFF // Greek Extended
1.155 + * U+2000 - U+206F // General Punctuation
1.156 + * U+2070 - U+209F // Superscripts and Subscripts
1.157 + * U+20A0 - U+20CF // Currency Symbols
1.158 + * U+2150 - U+218F // Number Forms
1.159 + * U+2460 - U+24FF // Enclosed Alphanumerics
1.160 + * U+2C60 - U+2C7F // Latin Extended-C
1.161 + * U+2DE0 - U+2DFF // Cyrillic Extended-A
1.162 + * U+2E00 - U+2E7F // Supplemental Punctuation
1.163 + * U+A640 - U+A69F // Cyrillic Extended-B
1.164 + * U+A720 - U+A7FF // Latin Extended-D
1.165 + * U+FB00 - U+FB06 // Alphab. Present. Forms (Latin Ligatures)
1.166 + * U+1D400 - U+1D7FF // Mathematical Alphanumeric Symbols
1.167 + * U+1F100 - U+1F1FF // Enclosed Alphanumeric Supplement
1.168 + * }
1.169 + *
1.170 + * FT_AUTOHINTER_SCRIPT_CJK ::
1.171 + * Apply the CJK auto-hinter, covering Chinese, Japanese, Korean, old
1.172 + * Vietnamese, and some other scripts.
1.173 + *
1.174 + * By default, characters from the following Unicode ranges are
1.175 + * assigned to this submodule.
1.176 + *
1.177 + * {
1.178 + * U+1100 - U+11FF // Hangul Jamo
1.179 + * U+2E80 - U+2EFF // CJK Radicals Supplement
1.180 + * U+2F00 - U+2FDF // Kangxi Radicals
1.181 + * U+2FF0 - U+2FFF // Ideographic Description Characters
1.182 + * U+3000 - U+303F // CJK Symbols and Punctuation
1.183 + * U+3040 - U+309F // Hiragana
1.184 + * U+30A0 - U+30FF // Katakana
1.185 + * U+3100 - U+312F // Bopomofo
1.186 + * U+3130 - U+318F // Hangul Compatibility Jamo
1.187 + * U+3190 - U+319F // Kanbun
1.188 + * U+31A0 - U+31BF // Bopomofo Extended
1.189 + * U+31C0 - U+31EF // CJK Strokes
1.190 + * U+31F0 - U+31FF // Katakana Phonetic Extensions
1.191 + * U+3200 - U+32FF // Enclosed CJK Letters and Months
1.192 + * U+3300 - U+33FF // CJK Compatibility
1.193 + * U+3400 - U+4DBF // CJK Unified Ideographs Extension A
1.194 + * U+4DC0 - U+4DFF // Yijing Hexagram Symbols
1.195 + * U+4E00 - U+9FFF // CJK Unified Ideographs
1.196 + * U+A960 - U+A97F // Hangul Jamo Extended-A
1.197 + * U+AC00 - U+D7AF // Hangul Syllables
1.198 + * U+D7B0 - U+D7FF // Hangul Jamo Extended-B
1.199 + * U+F900 - U+FAFF // CJK Compatibility Ideographs
1.200 + * U+FE10 - U+FE1F // Vertical forms
1.201 + * U+FE30 - U+FE4F // CJK Compatibility Forms
1.202 + * U+FF00 - U+FFEF // Halfwidth and Fullwidth Forms
1.203 + * U+1B000 - U+1B0FF // Kana Supplement
1.204 + * U+1D300 - U+1D35F // Tai Xuan Hing Symbols
1.205 + * U+1F200 - U+1F2FF // Enclosed Ideographic Supplement
1.206 + * U+20000 - U+2A6DF // CJK Unified Ideographs Extension B
1.207 + * U+2A700 - U+2B73F // CJK Unified Ideographs Extension C
1.208 + * U+2B740 - U+2B81F // CJK Unified Ideographs Extension D
1.209 + * U+2F800 - U+2FA1F // CJK Compatibility Ideographs Supplement
1.210 + * }
1.211 + *
1.212 + * FT_AUTOHINTER_SCRIPT_INDIC ::
1.213 + * Apply the indic auto-hinter, covering all major scripts from the
1.214 + * Indian sub-continent and some other related scripts like Thai, Lao,
1.215 + * or Tibetan.
1.216 + *
1.217 + * By default, characters from the following Unicode ranges are
1.218 + * assigned to this submodule.
1.219 + *
1.220 + * {
1.221 + * U+0900 - U+0DFF // Indic Range
1.222 + * U+0F00 - U+0FFF // Tibetan
1.223 + * U+1900 - U+194F // Limbu
1.224 + * U+1B80 - U+1BBF // Sundanese
1.225 + * U+1C80 - U+1CDF // Meetei Mayak
1.226 + * U+A800 - U+A82F // Syloti Nagri
1.227 + * U+11800 - U+118DF // Sharada
1.228 + * }
1.229 + *
1.230 + * Note that currently Indic support is rudimentary only, missing blue
1.231 + * zone support.
1.232 + *
1.233 + */
1.234 +#define FT_AUTOHINTER_SCRIPT_NONE 0
1.235 +#define FT_AUTOHINTER_SCRIPT_LATIN 1
1.236 +#define FT_AUTOHINTER_SCRIPT_CJK 2
1.237 +#define FT_AUTOHINTER_SCRIPT_INDIC 3
1.238 +
1.239 +
1.240 + /**************************************************************************
1.241 + *
1.242 + * @struct:
1.243 + * FT_Prop_GlyphToScriptMap
1.244 + *
1.245 + * @description:
1.246 + * *Experimental* *only*
1.247 + *
1.248 + * The data exchange structure for the @glyph-to-script-map property.
1.249 + *
1.250 + */
1.251 + typedef struct FT_Prop_GlyphToScriptMap_
1.252 + {
1.253 + FT_Face face;
1.254 + FT_Byte* map;
1.255 +
1.256 + } FT_Prop_GlyphToScriptMap;
1.257 +
1.258 +
1.259 + /**************************************************************************
1.260 + *
1.261 + * @property:
1.262 + * fallback-script
1.263 + *
1.264 + * @description:
1.265 + * *Experimental* *only*
1.266 + *
1.267 + * If no auto-hinter script module can be assigned to a glyph, a
1.268 + * fallback script gets assigned to it (see also the
1.269 + * @glyph-to-script-map property). By default, this is
1.270 + * @FT_AUTOHINTER_SCRIPT_CJK. Using the `fallback-script' property,
1.271 + * this fallback value can be changed.
1.272 + *
1.273 + * {
1.274 + * FT_Library library;
1.275 + * FT_UInt fallback_script = FT_AUTOHINTER_SCRIPT_NONE;
1.276 + *
1.277 + *
1.278 + * FT_Init_FreeType( &library );
1.279 + *
1.280 + * FT_Property_Set( library, "autofitter",
1.281 + * "fallback-script", &fallback_script );
1.282 + * }
1.283 + *
1.284 + * @note:
1.285 + * This property can be used with @FT_Property_Get also.
1.286 + *
1.287 + * It's important to use the right timing for changing this value: The
1.288 + * creation of the glyph-to-script map that eventually uses the
1.289 + * fallback script value gets triggered either by setting or reading a
1.290 + * face-specific property like @glyph-to-script-map, or by auto-hinting
1.291 + * any glyph from that face. In particular, if you have already created
1.292 + * an @FT_Face structure but not loaded any glyph (using the
1.293 + * auto-hinter), a change of the fallback script will affect this face.
1.294 + *
1.295 + */
1.296 +
1.297 +
1.298 + /**************************************************************************
1.299 + *
1.300 + * @property:
1.301 + * default-script
1.302 + *
1.303 + * @description:
1.304 + * *Experimental* *only*
1.305 + *
1.306 + * If Freetype gets compiled with FT_CONFIG_OPTION_USE_HARFBUZZ to make
1.307 + * the HarfBuzz library access OpenType features for getting better
1.308 + * glyph coverages, this property sets the (auto-fitter) script to be
1.309 + * used for the default (OpenType) script data of a font's GSUB table.
1.310 + * Features for the default script are intended for all scripts not
1.311 + * explicitly handled in GSUB; an example is a `dlig' feature,
1.312 + * containing the combination of the characters `T', `E', and `L' to
1.313 + * form a `TEL' ligature.
1.314 + *
1.315 + * By default, this is @FT_AUTOHINTER_SCRIPT_LATIN. Using the
1.316 + * `default-script' property, this default value can be changed.
1.317 + *
1.318 + * {
1.319 + * FT_Library library;
1.320 + * FT_UInt default_script = FT_AUTOHINTER_SCRIPT_NONE;
1.321 + *
1.322 + *
1.323 + * FT_Init_FreeType( &library );
1.324 + *
1.325 + * FT_Property_Set( library, "autofitter",
1.326 + * "default-script", &default_script );
1.327 + * }
1.328 + *
1.329 + * @note:
1.330 + * This property can be used with @FT_Property_Get also.
1.331 + *
1.332 + * It's important to use the right timing for changing this value: The
1.333 + * creation of the glyph-to-script map that eventually uses the
1.334 + * default script value gets triggered either by setting or reading a
1.335 + * face-specific property like @glyph-to-script-map, or by auto-hinting
1.336 + * any glyph from that face. In particular, if you have already created
1.337 + * an @FT_Face structure but not loaded any glyph (using the
1.338 + * auto-hinter), a change of the default script will affect this face.
1.339 + *
1.340 + */
1.341 +
1.342 +
1.343 + /**************************************************************************
1.344 + *
1.345 + * @property:
1.346 + * increase-x-height
1.347 + *
1.348 + * @description:
1.349 + * For ppem values in the range 6~<= ppem <= `increase-x-height', round
1.350 + * up the font's x~height much more often than normally. If the value
1.351 + * is set to~0, which is the default, this feature is switched off. Use
1.352 + * this property to improve the legibility of small font sizes if
1.353 + * necessary.
1.354 + *
1.355 + * {
1.356 + * FT_Library library;
1.357 + * FT_Face face;
1.358 + * FT_Prop_IncreaseXHeight prop;
1.359 + *
1.360 + *
1.361 + * FT_Init_FreeType( &library );
1.362 + * FT_New_Face( library, "foo.ttf", 0, &face );
1.363 + * FT_Set_Char_Size( face, 10 * 64, 0, 72, 0 );
1.364 + *
1.365 + * prop.face = face;
1.366 + * prop.limit = 14;
1.367 + *
1.368 + * FT_Property_Set( library, "autofitter",
1.369 + * "increase-x-height", &prop );
1.370 + * }
1.371 + *
1.372 + * @note:
1.373 + * This property can be used with @FT_Property_Get also.
1.374 + *
1.375 + * Set this value right after calling @FT_Set_Char_Size, but before
1.376 + * loading any glyph (using the auto-hinter).
1.377 + *
1.378 + */
1.379 +
1.380 +
1.381 + /**************************************************************************
1.382 + *
1.383 + * @struct:
1.384 + * FT_Prop_IncreaseXHeight
1.385 + *
1.386 + * @description:
1.387 + * The data exchange structure for the @increase-x-height property.
1.388 + *
1.389 + */
1.390 + typedef struct FT_Prop_IncreaseXHeight_
1.391 + {
1.392 + FT_Face face;
1.393 + FT_UInt limit;
1.394 +
1.395 + } FT_Prop_IncreaseXHeight;
1.396 +
1.397 +
1.398 + /* */
1.399 +
1.400 +FT_END_HEADER
1.401 +
1.402 +#endif /* __FTAUTOH_H__ */
1.403 +
1.404 +
1.405 +/* END */
