freetype.h: Improve Unicode Variation Sequence documentation.
This commit is contained in:
Werner Lemberg
parent
464b16ba46
commit
1c19b54999
|
|
@ -3804,40 +3804,51 @@ FT_BEGIN_HEADER
|
||||||
/* glyph_variants */
|
/* glyph_variants */
|
||||||
/* */
|
/* */
|
||||||
/* <Title> */
|
/* <Title> */
|
||||||
/* Glyph Variants */
|
/* Unicode Variation Sequences */
|
||||||
/* */
|
/* */
|
||||||
/* <Abstract> */
|
/* <Abstract> */
|
||||||
/* The FreeType~2 interface to Unicode Ideographic Variation */
|
/* The FreeType~2 interface to Unicode Variation Sequences (UVS), */
|
||||||
/* Sequences (IVS), using the SFNT cmap format~14. */
|
/* using the SFNT cmap format~14. */
|
||||||
/* */
|
/* */
|
||||||
/* <Description> */
|
/* <Description> */
|
||||||
/* Many CJK characters have variant forms. They are a sort of grey */
|
/* Many characters, especially for CJK scripts, have variant forms. */
|
||||||
/* area somewhere between being totally irrelevant and semantically */
|
/* They are a sort of grey area somewhere between being totally */
|
||||||
/* distinct; for this reason, the Unicode consortium decided to */
|
/* irrelevant and semantically distinct; for this reason, the Unicode */
|
||||||
/* introduce Ideographic Variation Sequences (IVS), consisting of a */
|
/* consortium decided to introduce Variation Sequences (VS), */
|
||||||
/* Unicode base character and one of 240 variant selectors */
|
/* consisting of a Unicode base character and a variation selector */
|
||||||
/* (U+E0100-U+E01EF), instead of further extending the already huge */
|
/* instead of further extending the already huge number of */
|
||||||
/* code range for CJK characters. */
|
/* characters. */
|
||||||
/* */
|
/* */
|
||||||
/* An IVS is registered and unique; for further details please refer */
|
/* Unicode maintains two different sets, namely `Standardized */
|
||||||
/* to Unicode Technical Standard #37, the Ideographic Variation */
|
/* Variation Sequences' and registered `Ideographic Variation */
|
||||||
/* Database: */
|
/* Sequences' (IVS), collected in the `Ideographic Variation */
|
||||||
|
/* Database' (IVD). */
|
||||||
/* */
|
/* */
|
||||||
/* http://www.unicode.org/reports/tr37/ */
|
/* http://unicode.org/Public/UCD/latest/ucd/StandardizedVariants.txt */
|
||||||
/* http://www.unicode.org/ivd/ */
|
/* http://unicode.org/reports/tr37/ */
|
||||||
|
/* http://unicode.org/ivd/ */
|
||||||
/* */
|
/* */
|
||||||
/* To date (January 2017), the character with the most variants is */
|
/* To date (January 2017), the character with the most ideographic */
|
||||||
/* U+9089, having 32 such IVS. */
|
/* variations is U+9089, having 32 such IVS. */
|
||||||
/* */
|
/* */
|
||||||
/* Adobe and MS decided to support IVS with a new cmap subtable */
|
/* Three Mongolian Variation Selectors have the values U+180B-U+180D; */
|
||||||
/* (format~14). It is an odd subtable because it is not a mapping of */
|
/* 256 generic Variation Selectors are encoded in the ranges */
|
||||||
/* input code points to glyphs, but contains lists of all variants */
|
/* U+FE00-U+FE0F and U+E0100-U+E01EF. IVS currently use Variation */
|
||||||
/* supported by the font. */
|
/* Selectors from the range U+E0100-U+E01EF only. */
|
||||||
/* */
|
/* */
|
||||||
/* A variant may be either `default' or `non-default'. A default */
|
/* A VS consists of the base character value followed by a single */
|
||||||
/* variant is the one you will get for that code point if you look it */
|
/* Variation Selector. For example, to get the first variation of */
|
||||||
/* up in the standard Unicode cmap. A non-default variant is a */
|
/* U+9089, you have to write the character sequence `U+9089 U+E0100'. */
|
||||||
/* different glyph. */
|
/* */
|
||||||
|
/* Adobe and MS decided to support both standardized and ideographic */
|
||||||
|
/* VS with a new cmap subtable (format~14). It is an odd subtable */
|
||||||
|
/* because it is not a mapping of input code points to glyphs, but */
|
||||||
|
/* contains lists of all variations supported by the font. */
|
||||||
|
/* */
|
||||||
|
/* A variation may be either `default' or `non-default' for a given */
|
||||||
|
/* font. A default variation is the one you will get for that code */
|
||||||
|
/* point if you look it up in the standard Unicode cmap. A */
|
||||||
|
/* non-default variation is a different glyph. */
|
||||||
/* */
|
/* */
|
||||||
/*************************************************************************/
|
/*************************************************************************/
|
||||||
|
|
||||||
|
|
@ -3893,8 +3904,8 @@ FT_BEGIN_HEADER
|
||||||
/* FT_Face_GetCharVariantIsDefault */
|
/* FT_Face_GetCharVariantIsDefault */
|
||||||
/* */
|
/* */
|
||||||
/* <Description> */
|
/* <Description> */
|
||||||
/* Check whether this variant of this Unicode character is the one to */
|
/* Check whether this variation of this Unicode character is the one */
|
||||||
/* be found in the `cmap'. */
|
/* to be found in the `cmap'. */
|
||||||
/* */
|
/* */
|
||||||
/* <Input> */
|
/* <Input> */
|
||||||
/* face :: */
|
/* face :: */
|
||||||
|
|
@ -3908,7 +3919,7 @@ FT_BEGIN_HEADER
|
||||||
/* */
|
/* */
|
||||||
/* <Return> */
|
/* <Return> */
|
||||||
/* 1~if found in the standard (Unicode) cmap, 0~if found in the */
|
/* 1~if found in the standard (Unicode) cmap, 0~if found in the */
|
||||||
/* variation selector cmap, or -1 if it is not a variant. */
|
/* variation selector cmap, or -1 if it is not a variation. */
|
||||||
/* */
|
/* */
|
||||||
/* <Note> */
|
/* <Note> */
|
||||||
/* This function is only meaningful if the font has a variation */
|
/* This function is only meaningful if the font has a variation */
|
||||||
|
|
@ -3929,7 +3940,7 @@ FT_BEGIN_HEADER
|
||||||
/* FT_Face_GetVariantSelectors */
|
/* FT_Face_GetVariantSelectors */
|
||||||
/* */
|
/* */
|
||||||
/* <Description> */
|
/* <Description> */
|
||||||
/* Return a zero-terminated list of Unicode variant selectors found */
|
/* Return a zero-terminated list of Unicode variation selectors found */
|
||||||
/* in the font. */
|
/* in the font. */
|
||||||
/* */
|
/* */
|
||||||
/* <Input> */
|
/* <Input> */
|
||||||
|
|
@ -3938,7 +3949,7 @@ FT_BEGIN_HEADER
|
||||||
/* */
|
/* */
|
||||||
/* <Return> */
|
/* <Return> */
|
||||||
/* A pointer to an array of selector code points, or NULL if there is */
|
/* A pointer to an array of selector code points, or NULL if there is */
|
||||||
/* no valid variant selector cmap subtable. */
|
/* no valid variation selector cmap subtable. */
|
||||||
/* */
|
/* */
|
||||||
/* <Note> */
|
/* <Note> */
|
||||||
/* The last item in the array is~0; the array is owned by the */
|
/* The last item in the array is~0; the array is owned by the */
|
||||||
|
|
@ -3958,7 +3969,7 @@ FT_BEGIN_HEADER
|
||||||
/* FT_Face_GetVariantsOfChar */
|
/* FT_Face_GetVariantsOfChar */
|
||||||
/* */
|
/* */
|
||||||
/* <Description> */
|
/* <Description> */
|
||||||
/* Return a zero-terminated list of Unicode variant selectors found */
|
/* Return a zero-terminated list of Unicode variation selectors found */
|
||||||
/* for the specified character code. */
|
/* for the specified character code. */
|
||||||
/* */
|
/* */
|
||||||
/* <Input> */
|
/* <Input> */
|
||||||
|
|
@ -3969,7 +3980,7 @@ FT_BEGIN_HEADER
|
||||||
/* The character codepoint in Unicode. */
|
/* The character codepoint in Unicode. */
|
||||||
/* */
|
/* */
|
||||||
/* <Return> */
|
/* <Return> */
|
||||||
/* A pointer to an array of variant selector code points that are */
|
/* A pointer to an array of variation selector code points that are */
|
||||||
/* active for the given character, or NULL if the corresponding list */
|
/* active for the given character, or NULL if the corresponding list */
|
||||||
/* is empty. */
|
/* is empty. */
|
||||||
/* */
|
/* */
|
||||||
|
|
@ -3993,19 +4004,19 @@ FT_BEGIN_HEADER
|
||||||
/* */
|
/* */
|
||||||
/* <Description> */
|
/* <Description> */
|
||||||
/* Return a zero-terminated list of Unicode character codes found for */
|
/* Return a zero-terminated list of Unicode character codes found for */
|
||||||
/* the specified variant selector. */
|
/* the specified variation selector. */
|
||||||
/* */
|
/* */
|
||||||
/* <Input> */
|
/* <Input> */
|
||||||
/* face :: */
|
/* face :: */
|
||||||
/* A handle to the source face object. */
|
/* A handle to the source face object. */
|
||||||
/* */
|
/* */
|
||||||
/* variantSelector :: */
|
/* variantSelector :: */
|
||||||
/* The variant selector code point in Unicode. */
|
/* The variation selector code point in Unicode. */
|
||||||
/* */
|
/* */
|
||||||
/* <Return> */
|
/* <Return> */
|
||||||
/* A list of all the code points that are specified by this selector */
|
/* A list of all the code points that are specified by this selector */
|
||||||
/* (both default and non-default codes are returned) or NULL if there */
|
/* (both default and non-default codes are returned) or NULL if there */
|
||||||
/* is no valid cmap or the variant selector is invalid. */
|
/* is no valid cmap or the variation selector is invalid. */
|
||||||
/* */
|
/* */
|
||||||
/* <Note> */
|
/* <Note> */
|
||||||
/* The last item in the array is~0; the array is owned by the */
|
/* The last item in the array is~0; the array is owned by the */
|
||||||
|
|
|
||||||
Loading…
Reference in New Issue