--- /dev/null
+/***************************************************************************/
+/* */
+/* ftautoh.h */
+/* */
+/* FreeType API for controlling the auto-hinter (specification only). */
+/* */
+/* Copyright 2012 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 <ft2build.h>
+#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:
+ * 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:
+ * 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:
+ * 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:
+ * 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 */
git.r.bdr.sh / rbdr / super-polarity / blobdiff