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/***************************************************************************/

/*                                                                         */

/*  ftautoh.h                                                              */

/*                                                                         */

/*    FreeType API for controlling the auto-hinter (specification only).   */

/*                                                                         */

/*  Copyright 2012, 2013 by                                                */

/*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */

/*                                                                         */

/*  This file is part of the FreeType project, and may only be used,       */

/*  modified, and distributed under the terms of the FreeType project      */

/*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */

/*  this file you indicate that you have read the license and              */

/*  understand and accept it fully.                                        */

/*                                                                         */

/***************************************************************************/

#ifndef __FTAUTOH_H__

#define __FTAUTOH_H__

#include 

#include FT_FREETYPE_H

#ifdef FREETYPE_H

#error "freetype.h of FreeType 1 has been loaded!"

#error "Please fix the directory search order for header files"

#error "so that freetype.h of FreeType 2 is found first."

#endif

FT_BEGIN_HEADER

  /**************************************************************************

   *

   * @section:

   *   auto_hinter

   *

   * @title:

   *   The auto-hinter

   *

   * @abstract:

   *   Controlling the auto-hinting module.

   *

   * @description:

   *   While FreeType's auto-hinter doesn't expose API functions by itself,

   *   it is possible to control its behaviour with @FT_Property_Set and

   *   @FT_Property_Get.  The following lists the available properties

   *   together with the necessary macros and structures.

   *

   *   Note that the auto-hinter's module name is `autofitter' for

   *   historical reasons.

   *

   */

  /**************************************************************************

   *

   * @property:

   *   glyph-to-script-map

   *

   * @description:

   *   *Experimental* *only*

   *

   *   The auto-hinter provides various script modules to hint glyphs.

   *   Examples of supported scripts are Latin or CJK.  Before a glyph is

   *   auto-hinted, the Unicode character map of the font gets examined, and

   *   the script is then determined based on Unicode character ranges, see

   *   below.

   *

   *   OpenType fonts, however, often provide much more glyphs than

   *   character codes (small caps, superscripts, ligatures, swashes, etc.),

   *   to be controlled by so-called `features'.  Handling OpenType features

   *   can be quite complicated and thus needs a separate library on top of

   *   FreeType.

   *

   *   The mapping between glyph indices and scripts (in the auto-hinter

   *   sense, see the @FT_AUTOHINTER_SCRIPT_XXX values) is stored as an

   *   array with `num_glyphs' elements, as found in the font's @FT_Face

   *   structure.  The `glyph-to-script-map' property returns a pointer to

   *   this array which can be modified as needed.  Note that the

   *   modification should happen before the first glyph gets processed by

   *   the auto-hinter so that the global analysis of the font shapes

   *   actually uses the modified mapping.

   *

   *   The following example code demonstrates how to access it (omitting

   *   the error handling).

   *

   *   {

   *     FT_Library                library;

   *     FT_Face                   face;

   *     FT_Prop_GlyphToScriptMap  prop;

   *

   *

   *     FT_Init_FreeType( &library );

   *     FT_New_Face( library, "foo.ttf", 0, &face );

   *

   *     prop.face = face;

   *

   *     FT_Property_Get( library, "autofitter",

   *                               "glyph-to-script-map", &prop );

   *

   *     // adjust `prop.map' as needed right here

   *

   *     FT_Load_Glyph( face, ..., FT_LOAD_FORCE_AUTOHINT );

   *   }

   *

   */

  /**************************************************************************

   *

   * @enum:

   *   FT_AUTOHINTER_SCRIPT_XXX

   *

   * @description:

   *   *Experimental* *only*

   *

   *   A list of constants used for the @glyph-to-script-map property to

   *   specify the script submodule the auto-hinter should use for hinting a

   *   particular glyph.

   *

   * @values:

   *   FT_AUTOHINTER_SCRIPT_NONE ::

   *     Don't auto-hint this glyph.

   *

   *   FT_AUTOHINTER_SCRIPT_LATIN ::

   *     Apply the latin auto-hinter.  For the auto-hinter, `latin' is a

   *     very broad term, including Cyrillic and Greek also since characters

   *     from those scripts share the same design constraints.

   *

   *     By default, characters from the following Unicode ranges are

   *     assigned to this submodule.

   *

   *     {

   *       U+0020 - U+007F  // Basic Latin (no control characters)

   *       U+00A0 - U+00FF  // Latin-1 Supplement (no control characters)

   *       U+0100 - U+017F  // Latin Extended-A

   *       U+0180 - U+024F  // Latin Extended-B

   *       U+0250 - U+02AF  // IPA Extensions

   *       U+02B0 - U+02FF  // Spacing Modifier Letters

   *       U+0300 - U+036F  // Combining Diacritical Marks

   *       U+0370 - U+03FF  // Greek and Coptic

   *       U+0400 - U+04FF  // Cyrillic

   *       U+0500 - U+052F  // Cyrillic Supplement

   *       U+1D00 - U+1D7F  // Phonetic Extensions

   *       U+1D80 - U+1DBF  // Phonetic Extensions Supplement

   *       U+1DC0 - U+1DFF  // Combining Diacritical Marks Supplement

   *       U+1E00 - U+1EFF  // Latin Extended Additional

   *       U+1F00 - U+1FFF  // Greek Extended

   *       U+2000 - U+206F  // General Punctuation

   *       U+2070 - U+209F  // Superscripts and Subscripts

   *       U+20A0 - U+20CF  // Currency Symbols

   *       U+2150 - U+218F  // Number Forms

   *       U+2460 - U+24FF  // Enclosed Alphanumerics

   *       U+2C60 - U+2C7F  // Latin Extended-C

   *       U+2DE0 - U+2DFF  // Cyrillic Extended-A

   *       U+2E00 - U+2E7F  // Supplemental Punctuation

   *       U+A640 - U+A69F  // Cyrillic Extended-B

   *       U+A720 - U+A7FF  // Latin Extended-D

   *       U+FB00 - U+FB06  // Alphab. Present. Forms (Latin Ligatures)

   *      U+1D400 - U+1D7FF // Mathematical Alphanumeric Symbols

   *      U+1F100 - U+1F1FF // Enclosed Alphanumeric Supplement

   *     }

   *

   *   FT_AUTOHINTER_SCRIPT_CJK ::

   *     Apply the CJK auto-hinter, covering Chinese, Japanese, Korean, old

   *     Vietnamese, and some other scripts.

   *

   *     By default, characters from the following Unicode ranges are

   *     assigned to this submodule.

   *

   *     {

   *       U+1100 - U+11FF  // Hangul Jamo

   *       U+2E80 - U+2EFF  // CJK Radicals Supplement

   *       U+2F00 - U+2FDF  // Kangxi Radicals

   *       U+2FF0 - U+2FFF  // Ideographic Description Characters

   *       U+3000 - U+303F  // CJK Symbols and Punctuation

   *       U+3040 - U+309F  // Hiragana

   *       U+30A0 - U+30FF  // Katakana

   *       U+3100 - U+312F  // Bopomofo

   *       U+3130 - U+318F  // Hangul Compatibility Jamo

   *       U+3190 - U+319F  // Kanbun

   *       U+31A0 - U+31BF  // Bopomofo Extended

   *       U+31C0 - U+31EF  // CJK Strokes

   *       U+31F0 - U+31FF  // Katakana Phonetic Extensions

   *       U+3200 - U+32FF  // Enclosed CJK Letters and Months

   *       U+3300 - U+33FF  // CJK Compatibility

   *       U+3400 - U+4DBF  // CJK Unified Ideographs Extension A

   *       U+4DC0 - U+4DFF  // Yijing Hexagram Symbols

   *       U+4E00 - U+9FFF  // CJK Unified Ideographs

   *       U+A960 - U+A97F  // Hangul Jamo Extended-A

   *       U+AC00 - U+D7AF  // Hangul Syllables

   *       U+D7B0 - U+D7FF  // Hangul Jamo Extended-B

   *       U+F900 - U+FAFF  // CJK Compatibility Ideographs

   *       U+FE10 - U+FE1F  // Vertical forms

   *       U+FE30 - U+FE4F  // CJK Compatibility Forms

   *       U+FF00 - U+FFEF  // Halfwidth and Fullwidth Forms

   *      U+1B000 - U+1B0FF // Kana Supplement

   *      U+1D300 - U+1D35F // Tai Xuan Hing Symbols

   *      U+1F200 - U+1F2FF // Enclosed Ideographic Supplement

   *      U+20000 - U+2A6DF // CJK Unified Ideographs Extension B

   *      U+2A700 - U+2B73F // CJK Unified Ideographs Extension C

   *      U+2B740 - U+2B81F // CJK Unified Ideographs Extension D

   *      U+2F800 - U+2FA1F // CJK Compatibility Ideographs Supplement

   *     }

   *

   *   FT_AUTOHINTER_SCRIPT_INDIC ::

   *     Apply the indic auto-hinter, covering all major scripts from the

   *     Indian sub-continent and some other related scripts like Thai, Lao,

   *     or Tibetan.

   *

   *     By default, characters from the following Unicode ranges are

   *     assigned to this submodule.

   *

   *     {

   *       U+0900 - U+0DFF  // Indic Range

   *       U+0F00 - U+0FFF  // Tibetan

   *       U+1900 - U+194F  // Limbu

   *       U+1B80 - U+1BBF  // Sundanese

   *       U+1C80 - U+1CDF  // Meetei Mayak

   *       U+A800 - U+A82F  // Syloti Nagri

   *      U+11800 - U+118DF // Sharada

   *     }

   *

   *     Note that currently Indic support is rudimentary only, missing blue

   *     zone support.

   *

   */

#define FT_AUTOHINTER_SCRIPT_NONE   0

#define FT_AUTOHINTER_SCRIPT_LATIN  1

#define FT_AUTOHINTER_SCRIPT_CJK    2

#define FT_AUTOHINTER_SCRIPT_INDIC  3

  /**************************************************************************

   *

   * @struct:

   *   FT_Prop_GlyphToScriptMap

   *

   * @description:

   *   *Experimental* *only*

   *

   *   The data exchange structure for the @glyph-to-script-map property.

   *

   */

   typedef struct  FT_Prop_GlyphToScriptMap_

   {

     FT_Face   face;

     FT_Byte*  map;

   } FT_Prop_GlyphToScriptMap;

  /**************************************************************************

   *

   * @property:

   *   fallback-script

   *

   * @description:

   *   *Experimental* *only*

   *

   *   If no auto-hinter script module can be assigned to a glyph, a

   *   fallback script gets assigned to it (see also the

   *   @glyph-to-script-map property).  By default, this is

   *   @FT_AUTOHINTER_SCRIPT_CJK.  Using the `fallback-script' property,

   *   this fallback value can be changed.

   *

   *   {

   *     FT_Library  library;

   *     FT_UInt     fallback_script = FT_AUTOHINTER_SCRIPT_NONE;

   *

   *

   *     FT_Init_FreeType( &library );

   *

   *     FT_Property_Set( library, "autofitter",

   *                               "fallback-script", &fallback_script );

   *   }

   *

   * @note:

   *   This property can be used with @FT_Property_Get also.

   *

   *   It's important to use the right timing for changing this value: The

   *   creation of the glyph-to-script map which eventually uses the

   *   fallback script value gets triggered either by setting or reading a

   *   face-specific property like @glyph-to-script-map, or by auto-hinting

   *   any glyph from that face.  In particular, if you have already created

   *   an @FT_Face structure but not loaded any glyph (using the

   *   auto-hinter), a change of the fallback glyph will affect this face.

   *

   */

  /**************************************************************************

   *

   * @property:

   *   increase-x-height

   *

   * @description:

   *   For ppem values in the range 6~<= ppem <= `increase-x-height', round

   *   up the font's x~height much more often than normally.  If the value

   *   is set to~0, which is the default, this feature is switched off.  Use

   *   this property to improve the legibility of small font sizes if

   *   necessary.

   *

   *   {

   *     FT_Library               library;

   *     FT_Face                  face;

   *     FT_Prop_IncreaseXHeight  prop;

   *

   *

   *     FT_Init_FreeType( &library );

   *     FT_New_Face( library, "foo.ttf", 0, &face );

   *     FT_Set_Char_Size( face, 10 * 64, 0, 72, 0 );

   *

   *     prop.face  = face;

   *     prop.limit = 14;

   *

   *     FT_Property_Set( library, "autofitter",

   *                               "increase-x-height", &prop );

   *   }

   *

   * @note:

   *   This property can be used with @FT_Property_Get also.

   *

   *   Set this value right after calling @FT_Set_Char_Size, but before

   *   loading any glyph (using the auto-hinter).

   *

   */

  /**************************************************************************

   *

   * @struct:

   *   FT_Prop_IncreaseXHeight

   *

   * @description:

   *   The data exchange structure for the @increase-x-height property.

   *

   */

   typedef struct  FT_Prop_IncreaseXHeight_

   {

     FT_Face  face;

     FT_UInt  limit;

   } FT_Prop_IncreaseXHeight;

 /* */

FT_END_HEADER

#endif /* __FTAUTOH_H__ */

/* END */