manpagez: man pages & more
html files: pango
Home | html | info | man

OpenType Font Handling

OpenType Font Handling — Obtaining information from OpenType tables

Stability Level

Unstable, unless otherwise indicated

Object Hierarchy

    GObject
    ├── PangoOTInfo
    ╰── PangoOTRuleset

Description

Functions and macros in this section are used to implement the OpenType Layout features and algorithms. These are mostly useful when writing Fontconfig-based shaping engines

Functions

PANGO_OT_TAG_MAKE()

#define PANGO_OT_TAG_MAKE(c1,c2,c3,c4)		((PangoOTTag) FT_MAKE_TAG (c1, c2, c3, c4))

Creates a PangoOTTag from four characters. This is similar and compatible with the FT_MAKE_TAG() macro from FreeType.

Parameters

c1

First character.

 

c2

Second character.

 

c3

Third character.

 

c4

Fourth character.

 

PANGO_OT_TAG_MAKE_FROM_STRING()

#define             PANGO_OT_TAG_MAKE_FROM_STRING(s)

Creates a PangoOTTag from a string. The string should be at least four characters long (pad with space characters if needed), and need not be nul-terminated. This is a convenience wrapper around PANGO_OT_TAG_MAKE(), but cannot be used in certain situations, for example, as a switch expression, as it dereferences pointers.

Parameters

s

The string representation of the tag.

 

pango_ot_info_get ()

PangoOTInfo *
pango_ot_info_get (FT_Face face);

pango_ot_info_get is deprecated and should not be used in newly-written code.

Returns the PangoOTInfo structure for the given FreeType font face.

Parameters

face

a FT_Face.

 

Returns

the PangoOTInfo for face . This object will have the same lifetime as face .

Since: 1.2


pango_ot_info_find_script ()

gboolean
pango_ot_info_find_script (PangoOTInfo *info,
                           PangoOTTableType table_type,
                           PangoOTTag script_tag,
                           guint *script_index);

pango_ot_info_find_script is deprecated and should not be used in newly-written code.

Finds the index of a script. If not found, tries to find the 'DFLT' and then 'dflt' scripts and return the index of that in script_index . If none of those is found either, PANGO_OT_NO_SCRIPT is placed in script_index .

All other functions taking an input script_index parameter know how to handle PANGO_OT_NO_SCRIPT, so one can ignore the return value of this function completely and proceed, to enjoy the automatic fallback to the 'DFLT'/'dflt' script.

Parameters

info

a PangoOTInfo.

 

table_type

the table type to obtain information about.

 

script_tag

the tag of the script to find.

 

script_index

location to store the index of the script, or NULL.

[out][optional]

Returns

TRUE if the script was found.


pango_ot_info_find_language ()

gboolean
pango_ot_info_find_language (PangoOTInfo *info,
                             PangoOTTableType table_type,
                             guint script_index,
                             PangoOTTag language_tag,
                             guint *language_index,
                             guint *required_feature_index);

pango_ot_info_find_language is deprecated and should not be used in newly-written code.

Finds the index of a language and its required feature index. If the language is not found, sets language_index to PANGO_OT_DEFAULT_LANGUAGE and the required feature of the default language system is returned in required_feature_index. For best compatibility with some fonts, also searches the language system tag 'dflt' before falling back to the default language system, but that is transparent to the user. The user can simply ignore the return value of this function to automatically fall back to the default language system.

Parameters

info

a PangoOTInfo.

 

table_type

the table type to obtain information about.

 

script_index

the index of the script whose languages are searched.

 

language_tag

the tag of the language to find.

 

language_index

location to store the index of the language, or NULL.

[out][optional]

required_feature_index

location to store the required feature index of the language, or NULL.

[out][optional]

Returns

TRUE if the language was found.


pango_ot_info_find_feature ()

gboolean
pango_ot_info_find_feature (PangoOTInfo *info,
                            PangoOTTableType table_type,
                            PangoOTTag feature_tag,
                            guint script_index,
                            guint language_index,
                            guint *feature_index);

pango_ot_info_find_feature is deprecated and should not be used in newly-written code.

Finds the index of a feature. If the feature is not found, sets feature_index to PANGO_OT_NO_FEATURE, which is safe to pass to pango_ot_ruleset_add_feature() and similar functions.

In the future, this may set feature_index to an special value that if used in pango_ot_ruleset_add_feature() will ask Pango to synthesize the requested feature based on Unicode properties and data. However, this function will still return FALSE in those cases. So, users may want to ignore the return value of this function in certain cases.

Parameters

info

a PangoOTInfo.

 

table_type

the table type to obtain information about.

 

feature_tag

the tag of the feature to find.

 

script_index

the index of the script.

 

language_index

the index of the language whose features are searched, or PANGO_OT_DEFAULT_LANGUAGE to use the default language of the script.

 

feature_index

location to store the index of the feature, or NULL.

[out][optional]

Returns

TRUE if the feature was found.


pango_ot_info_list_scripts ()

PangoOTTag *
pango_ot_info_list_scripts (PangoOTInfo *info,
                            PangoOTTableType table_type);

pango_ot_info_list_scripts is deprecated and should not be used in newly-written code.

Obtains the list of available scripts.

Parameters

info

a PangoOTInfo.

 

table_type

the table type to obtain information about.

 

Returns

a newly-allocated zero-terminated array containing the tags of the available scripts. Should be freed using g_free().


pango_ot_info_list_languages ()

PangoOTTag *
pango_ot_info_list_languages (PangoOTInfo *info,
                              PangoOTTableType table_type,
                              guint script_index,
                              PangoOTTag language_tag);

pango_ot_info_list_languages is deprecated and should not be used in newly-written code.

Obtains the list of available languages for a given script.

Parameters

info

a PangoOTInfo.

 

table_type

the table type to obtain information about.

 

script_index

the index of the script to list languages for.

 

language_tag

unused parameter.

 

Returns

a newly-allocated zero-terminated array containing the tags of the available languages. Should be freed using g_free().


pango_ot_info_list_features ()

PangoOTTag *
pango_ot_info_list_features (PangoOTInfo *info,
                             PangoOTTableType table_type,
                             PangoOTTag tag,
                             guint script_index,
                             guint language_index);

pango_ot_info_list_features is deprecated and should not be used in newly-written code.

Obtains the list of features for the given language of the given script.

Parameters

info

a PangoOTInfo.

 

table_type

the table type to obtain information about.

 

tag

unused parameter.

 

script_index

the index of the script to obtain information about.

 

language_index

the index of the language to list features for, or PANGO_OT_DEFAULT_LANGUAGE, to list features for the default language of the script.

 

Returns

a newly-allocated zero-terminated array containing the tags of the available features. Should be freed using g_free().


pango_ot_buffer_new ()

PangoOTBuffer *
pango_ot_buffer_new (PangoFcFont *font);

pango_ot_buffer_new is deprecated and should not be used in newly-written code.

Creates a new PangoOTBuffer for the given OpenType font.

Parameters

font

a PangoFcFont

 

Returns

the newly allocated PangoOTBuffer, which should be freed with pango_ot_buffer_destroy().

Since: 1.4


pango_ot_buffer_destroy ()

void
pango_ot_buffer_destroy (PangoOTBuffer *buffer);

pango_ot_buffer_destroy is deprecated and should not be used in newly-written code.

Destroys a PangoOTBuffer and free all associated memory.

Parameters

buffer

a PangoOTBuffer

 

Since: 1.4


pango_ot_buffer_clear ()

void
pango_ot_buffer_clear (PangoOTBuffer *buffer);

pango_ot_buffer_clear is deprecated and should not be used in newly-written code.

Empties a PangoOTBuffer, make it ready to add glyphs to.

Parameters

buffer

a PangoOTBuffer

 

Since: 1.4


pango_ot_buffer_add_glyph ()

void
pango_ot_buffer_add_glyph (PangoOTBuffer *buffer,
                           guint glyph,
                           guint properties,
                           guint cluster);

pango_ot_buffer_add_glyph is deprecated and should not be used in newly-written code.

Appends a glyph to a PangoOTBuffer, with properties identifying which features should be applied on this glyph. See pango_ot_ruleset_add_feature().

Parameters

buffer

a PangoOTBuffer

 

glyph

the glyph index to add, like a PangoGlyph

 

properties

the glyph properties

 

cluster

the cluster that this glyph belongs to

 

Since: 1.4


pango_ot_buffer_set_rtl ()

void
pango_ot_buffer_set_rtl (PangoOTBuffer *buffer,
                         gboolean rtl);

pango_ot_buffer_set_rtl is deprecated and should not be used in newly-written code.

Sets whether glyphs will be rendered right-to-left. This setting is needed for proper horizontal positioning of right-to-left scripts.

Parameters

buffer

a PangoOTBuffer

 

rtl

TRUE for right-to-left text

 

Since: 1.4


pango_ot_buffer_set_zero_width_marks ()

void
pango_ot_buffer_set_zero_width_marks (PangoOTBuffer *buffer,
                                      gboolean zero_width_marks);

pango_ot_buffer_set_zero_width_marks is deprecated and should not be used in newly-written code.

Sets whether characters with a mark class should be forced to zero width. This setting is needed for proper positioning of Arabic accents, but will produce incorrect results with standard OpenType Indic fonts.

Parameters

buffer

a PangoOTBuffer

 

zero_width_marks

TRUE if characters with a mark class should be forced to zero width.

 

Since: 1.6


pango_ot_buffer_get_glyphs ()

void
pango_ot_buffer_get_glyphs (const PangoOTBuffer *buffer,
                            PangoOTGlyph **glyphs,
                            int *n_glyphs);

pango_ot_buffer_get_glyphs is deprecated and should not be used in newly-written code.

Gets the glyph array contained in a PangoOTBuffer. The glyphs are owned by the buffer and should not be freed, and are only valid as long as buffer is not modified.

Parameters

buffer

a PangoOTBuffer

 

glyphs

location to store the array of glyphs, or NULL.

[array length=n_glyphs][out][optional]

n_glyphs

location to store the number of glyphs, or NULL.

[out][optional]

Since: 1.4


pango_ot_buffer_output ()

void
pango_ot_buffer_output (const PangoOTBuffer *buffer,
                        PangoGlyphString *glyphs);

pango_ot_buffer_output is deprecated and should not be used in newly-written code.

Exports the glyphs in a PangoOTBuffer into a PangoGlyphString. This is typically used after the OpenType layout processing is over, to convert the resulting glyphs into a generic Pango glyph string.

Parameters

buffer

a PangoOTBuffer

 

glyphs

a PangoGlyphString

 

Since: 1.4


pango_ot_ruleset_get_for_description ()

const PangoOTRuleset *
pango_ot_ruleset_get_for_description (PangoOTInfo *info,
                                      const PangoOTRulesetDescription *desc);

pango_ot_ruleset_get_for_description is deprecated and should not be used in newly-written code.

Returns a ruleset for the given OpenType info and ruleset description. Rulesets are created on demand using pango_ot_ruleset_new_from_description(). The returned ruleset should not be modified or destroyed.

The static feature map members of desc should be alive as long as info is.

Parameters

info

a PangoOTInfo.

 

desc

a PangoOTRulesetDescription.

 

Returns

the PangoOTRuleset for desc . This object will have the same lifetime as info .

Since: 1.18


pango_ot_ruleset_new ()

PangoOTRuleset *
pango_ot_ruleset_new (PangoOTInfo *info);

pango_ot_ruleset_new is deprecated and should not be used in newly-written code.

Creates a new PangoOTRuleset for the given OpenType info.

Parameters

info

a PangoOTInfo.

 

Returns

the newly allocated PangoOTRuleset, which should be freed with g_object_unref().


pango_ot_ruleset_new_for ()

PangoOTRuleset *
pango_ot_ruleset_new_for (PangoOTInfo *info,
                          PangoScript script,
                          PangoLanguage *language);

pango_ot_ruleset_new_for is deprecated and should not be used in newly-written code.

Creates a new PangoOTRuleset for the given OpenType info, script, and language.

This function is part of a convenience scheme that highly simplifies using a PangoOTRuleset to represent features for a specific pair of script and language. So one can use this function passing in the script and language of interest, and later try to add features to the ruleset by just specifying the feature name or tag, without having to deal with finding script, language, or feature indices manually.

In excess to what pango_ot_ruleset_new() does, this function will:

Because of the way return values of pango_ot_info_find_script() and pango_ot_info_find_language() are ignored, this function automatically finds and uses the 'DFLT' script and the default language-system.

Parameters

info

a PangoOTInfo.

 

script

a PangoScript.

 

language

a PangoLanguage.

 

Returns

the newly allocated PangoOTRuleset, which should be freed with g_object_unref().

Since: 1.18


pango_ot_ruleset_new_from_description ()

PangoOTRuleset *
pango_ot_ruleset_new_from_description (PangoOTInfo *info,
                                       const PangoOTRulesetDescription *desc);

pango_ot_ruleset_new_from_description is deprecated and should not be used in newly-written code.

Creates a new PangoOTRuleset for the given OpenType infor and matching the given ruleset description.

This is a convenience function that calls pango_ot_ruleset_new_for() and adds the static GSUB/GPOS features to the resulting ruleset, followed by adding other features to both GSUB and GPOS.

The static feature map members of desc should be alive as long as info is.

Parameters

info

a PangoOTInfo.

 

desc

a PangoOTRulesetDescription.

 

Returns

the newly allocated PangoOTRuleset, which should be freed with g_object_unref().

Since: 1.18


pango_ot_ruleset_add_feature ()

void
pango_ot_ruleset_add_feature (PangoOTRuleset *ruleset,
                              PangoOTTableType table_type,
                              guint feature_index,
                              gulong property_bit);

pango_ot_ruleset_add_feature is deprecated and should not be used in newly-written code.

Adds a feature to the ruleset.

Parameters

ruleset

a PangoOTRuleset.

 

table_type

the table type to add a feature to.

 

feature_index

the index of the feature to add.

 

property_bit

the property bit to use for this feature. Used to identify the glyphs that this feature should be applied to, or PANGO_OT_ALL_GLYPHS if it should be applied to all glyphs.

 

pango_ot_ruleset_maybe_add_feature ()

gboolean
pango_ot_ruleset_maybe_add_feature (PangoOTRuleset *ruleset,
                                    PangoOTTableType table_type,
                                    PangoOTTag feature_tag,
                                    gulong property_bit);

pango_ot_ruleset_maybe_add_feature is deprecated and should not be used in newly-written code.

This is a convenience function that first tries to find the feature using pango_ot_info_find_feature() and the ruleset script and language passed to pango_ot_ruleset_new_for(), and if the feature is found, adds it to the ruleset.

If ruleset was not created using pango_ot_ruleset_new_for(), this function does nothing.

Parameters

ruleset

a PangoOTRuleset.

 

table_type

the table type to add a feature to.

 

feature_tag

the tag of the feature to add.

 

property_bit

the property bit to use for this feature. Used to identify the glyphs that this feature should be applied to, or PANGO_OT_ALL_GLYPHS if it should be applied to all glyphs.

 

Returns

TRUE if the feature was found and added to ruleset, FALSE otherwise.

Since: 1.18


pango_ot_ruleset_maybe_add_features ()

guint
pango_ot_ruleset_maybe_add_features (PangoOTRuleset *ruleset,
                                     PangoOTTableType table_type,
                                     const PangoOTFeatureMap *features,
                                     guint n_features);

pango_ot_ruleset_maybe_add_features is deprecated and should not be used in newly-written code.

This is a convenience function that for each feature in the feature map array features converts the feature name to a PangoOTTag feature tag using PANGO_OT_TAG_MAKE() and calls pango_ot_ruleset_maybe_add_feature() on it.

Parameters

ruleset

a PangoOTRuleset.

 

table_type

the table type to add features to.

 

features

array of feature name and property bits to add.

 

n_features

number of feature records in features array.

 

Returns

The number of features in features that were found and added to ruleset .

Since: 1.18


pango_ot_ruleset_get_feature_count ()

guint
pango_ot_ruleset_get_feature_count (const PangoOTRuleset *ruleset,
                                    guint *n_gsub_features,
                                    guint *n_gpos_features);

pango_ot_ruleset_get_feature_count is deprecated and should not be used in newly-written code.

Gets the number of GSUB and GPOS features in the ruleset.

Parameters

ruleset

a PangoOTRuleset.

 

n_gsub_features

location to store number of GSUB features, or NULL.

[out][optional]

n_gpos_features

location to store number of GPOS features, or NULL.

[out][optional]

Returns

Total number of features in the ruleset .

Since: 1.18


pango_ot_ruleset_substitute ()

void
pango_ot_ruleset_substitute (const PangoOTRuleset *ruleset,
                             PangoOTBuffer *buffer);

pango_ot_ruleset_substitute is deprecated and should not be used in newly-written code.

Performs the OpenType GSUB substitution on buffer using the features in ruleset

Parameters

ruleset

a PangoOTRuleset.

 

buffer

a PangoOTBuffer.

 

Since: 1.4


pango_ot_ruleset_position ()

void
pango_ot_ruleset_position (const PangoOTRuleset *ruleset,
                           PangoOTBuffer *buffer);

pango_ot_ruleset_position is deprecated and should not be used in newly-written code.

Performs the OpenType GPOS positioning on buffer using the features in ruleset

Parameters

ruleset

a PangoOTRuleset.

 

buffer

a PangoOTBuffer.

 

Since: 1.4


pango_ot_ruleset_description_copy ()

PangoOTRulesetDescription *
pango_ot_ruleset_description_copy (const PangoOTRulesetDescription *desc);

pango_ot_ruleset_description_copy is deprecated and should not be used in newly-written code.

Creates a copy of desc , which should be freed with pango_ot_ruleset_description_free(). Primarily used internally by pango_ot_ruleset_get_for_description() to cache rulesets for ruleset descriptions.

Parameters

desc

ruleset description to copy

 

Returns

the newly allocated PangoOTRulesetDescription, which should be freed with pango_ot_ruleset_description_free().

Since: 1.18


pango_ot_ruleset_description_equal ()

gboolean
pango_ot_ruleset_description_equal (const PangoOTRulesetDescription *desc1,
                                    const PangoOTRulesetDescription *desc2);

pango_ot_ruleset_description_equal is deprecated and should not be used in newly-written code.

Compares two ruleset descriptions for equality. Two ruleset descriptions are considered equal if the rulesets they describe are provably identical. This means that their script, language, and all feature sets should be equal. For static feature sets, the array addresses are compared directly, while for other features, the list of features is compared one by one. (Two ruleset descriptions may result in identical rulesets being created, but still compare FALSE.)

Parameters

desc1

a ruleset description

 

desc2

a ruleset description

 

Returns

TRUE if two ruleset descriptions are identical, FALSE otherwise.

Since: 1.18


pango_ot_ruleset_description_free ()

void
pango_ot_ruleset_description_free (PangoOTRulesetDescription *desc);

pango_ot_ruleset_description_free is deprecated and should not be used in newly-written code.

Frees a ruleset description allocated by pango_ot_ruleset_description_copy().

Parameters

desc

an allocated PangoOTRulesetDescription

 

Since: 1.18


pango_ot_ruleset_description_hash ()

guint
pango_ot_ruleset_description_hash (const PangoOTRulesetDescription *desc);

pango_ot_ruleset_description_hash is deprecated and should not be used in newly-written code.

Computes a hash of a PangoOTRulesetDescription structure suitable to be used, for example, as an argument to g_hash_table_new().

Parameters

desc

a ruleset description

 

Returns

the hash value.

Since: 1.18


pango_ot_tag_from_language ()

PangoOTTag
pango_ot_tag_from_language (PangoLanguage *language);

pango_ot_tag_from_language is deprecated and should not be used in newly-written code.

Finds the OpenType language-system tag best describing language .

Parameters

language

A PangoLanguage, or NULL.

[nullable]

Returns

PangoOTTag best matching language or PANGO_OT_TAG_DEFAULT_LANGUAGE if none found or if language is NULL.

Since: 1.18


pango_ot_tag_from_script ()

PangoOTTag
pango_ot_tag_from_script (PangoScript script);

pango_ot_tag_from_script is deprecated and should not be used in newly-written code.

Finds the OpenType script tag corresponding to script .

The PANGO_SCRIPT_COMMON, PANGO_SCRIPT_INHERITED, and PANGO_SCRIPT_UNKNOWN scripts are mapped to the OpenType 'DFLT' script tag that is also defined as PANGO_OT_TAG_DEFAULT_SCRIPT.

Note that multiple PangoScript values may map to the same OpenType script tag. In particular, PANGO_SCRIPT_HIRAGANA and PANGO_SCRIPT_KATAKANA both map to the OT tag 'kana'.

Parameters

script

A PangoScript

 

Returns

PangoOTTag corresponding to script or PANGO_OT_TAG_DEFAULT_SCRIPT if none found.

Since: 1.18


pango_ot_tag_to_language ()

PangoLanguage *
pango_ot_tag_to_language (PangoOTTag language_tag);

pango_ot_tag_to_language is deprecated and should not be used in newly-written code.

Finds a PangoLanguage corresponding to language_tag .

Parameters

language_tag

A PangoOTTag OpenType language-system tag

 

Returns

PangoLanguage best matching language_tag or PangoLanguage corresponding to the string "xx" if none found.

Since: 1.18


pango_ot_tag_to_script ()

PangoScript
pango_ot_tag_to_script (PangoOTTag script_tag);

pango_ot_tag_to_script is deprecated and should not be used in newly-written code.

Finds the PangoScript corresponding to script_tag .

The 'DFLT' script tag is mapped to PANGO_SCRIPT_COMMON.

Note that an OpenType script tag may correspond to multiple PangoScript values. In such cases, the PangoScript value with the smallest value is returned. In particular, PANGO_SCRIPT_HIRAGANA and PANGO_SCRIPT_KATAKANA both map to the OT tag 'kana'. This function will return PANGO_SCRIPT_HIRAGANA for 'kana'.

Parameters

script_tag

A PangoOTTag OpenType script tag

 

Returns

PangoScript corresponding to script_tag or PANGO_SCRIPT_UNKNOWN if none found.

Since: 1.18

Types and Values

PangoOTTag

typedef guint32 PangoOTTag;

The PangoOTTag typedef is used to represent TrueType and OpenType four letter tags inside Pango. Use PANGO_OT_TAG_MAKE() or PANGO_OT_TAG_MAKE_FROM_STRING() macros to create PangoOTTags manually.


PangoOTInfo

typedef struct _PangoOTInfo PangoOTInfo;

The PangoOTInfo struct contains the various tables associated with an OpenType font. It contains only private fields and should only be accessed via the pango_ot_info_* functions which are documented below. To obtain a PangoOTInfo, use pango_ot_info_get().


PangoOTBuffer

typedef struct _PangoOTBuffer PangoOTBuffer;

The PangoOTBuffer structure is used to store strings of glyphs associated with a PangoFcFont, suitable for OpenType layout processing. It contains only private fields and should only be accessed via the pango_ot_buffer_* functions which are documented below. To obtain a PangoOTBuffer, use pango_ot_buffer_new().


struct PangoOTGlyph

struct PangoOTGlyph {
  guint32  glyph;
  guint    properties;
  guint    cluster;
  gushort  component;
  gushort  ligID;

  guint    internal;
};

The PangoOTGlyph structure represents a single glyph together with information used for OpenType layout processing of the glyph. It contains the following fields.

Members

guint32 glyph;

the glyph itself.

 

guint properties;

the properties value, identifying which features should be applied on this glyph. See pango_ot_ruleset_add_feature().

 

guint cluster;

the cluster that this glyph belongs to.

 

gushort component;

a component value, set by the OpenType layout engine.

 

gushort ligID;

a ligature index value, set by the OpenType layout engine.

 

guint internal;

for Pango internal use

 

PangoOTRuleset

typedef struct _PangoOTRuleset PangoOTRuleset;

The PangoOTRuleset structure holds a set of features selected from the tables in an OpenType font. (A feature is an operation such as adjusting glyph positioning that should be applied to a text feature such as a certain type of accent.) A PangoOTRuleset is created with pango_ot_ruleset_new(), features are added to it with pango_ot_ruleset_add_feature(), then it is applied to a PangoGlyphString with pango_ot_ruleset_shape().


struct PangoOTRulesetDescription

struct PangoOTRulesetDescription {
  PangoScript               script;
  PangoLanguage            *language;
  const PangoOTFeatureMap  *static_gsub_features;
  guint                   n_static_gsub_features;
  const PangoOTFeatureMap  *static_gpos_features;
  guint                   n_static_gpos_features;
  const PangoOTFeatureMap  *other_features;
  guint                   n_other_features;
};

The PangoOTRuleset structure holds all the information needed to build a complete PangoOTRuleset from an OpenType font. The main use of this struct is to act as the key for a per-font hash of rulesets. The user populates a ruleset description and gets the ruleset using pango_ot_ruleset_get_for_description() or create a new one using pango_ot_ruleset_new_from_description().

Members

PangoScript script;

a PangoScript.

 

PangoLanguage *language;

a PangoLanguage.

 

const PangoOTFeatureMap *static_gsub_features;

static map of GSUB features, or NULL.

[nullable]

guint n_static_gsub_features;

length of static_gsub_features , or 0.

 

const PangoOTFeatureMap *static_gpos_features;

static map of GPOS features, or NULL.

[nullable]

guint n_static_gpos_features;

length of static_gpos_features , or 0.

 

const PangoOTFeatureMap *other_features;

map of extra features to add to both GSUB and GPOS, or NULL. Unlike the static maps, this pointer need not live beyond the life of function calls taking this struct.

[nullable]

guint n_other_features;

length of other_features , or 0.

 

Since: 1.18


enum PangoOTTableType

The PangoOTTableType enumeration values are used to identify the various OpenType tables in the pango_ot_info_* functions.

Members

PANGO_OT_TABLE_GSUB

The GSUB table.

 

PANGO_OT_TABLE_GPOS

The GPOS table.

 

struct PangoOTFeatureMap

struct PangoOTFeatureMap {
  char     feature_name[5];
  gulong   property_bit;
};

The PangoOTFeatureMap typedef is used to represent an OpenType feature with the property bit associated with it. The feature tag is represented as a char array instead of a PangoOTTag for convenience.

Members

char feature_name[5];

feature tag in represented as four-letter ASCII string.

 

gulong property_bit;

the property bit to use for this feature. See pango_ot_ruleset_add_feature() for details.

 

Since: 1.18


PANGO_OT_ALL_GLYPHS

#define PANGO_OT_ALL_GLYPHS			((guint) 0xFFFF)

This is used as the property bit in pango_ot_ruleset_add_feature() when a feature should be applied to all glyphs.

Since: 1.16


PANGO_OT_NO_FEATURE

#define PANGO_OT_NO_FEATURE			((guint) 0xFFFF)

This is used as a feature index that represent no feature, that is, should be skipped. It may be returned as feature index by pango_ot_info_find_feature() if the feature is not found, and pango_ot_ruleset_add_feature() function automatically skips this value, so no special handling is required by the user.

Since: 1.18


PANGO_OT_NO_SCRIPT

#define PANGO_OT_NO_SCRIPT			((guint) 0xFFFF)

This is used as a script index that represent no script, that is, when the requested script was not found, and a default ('DFLT') script was not found either. It may be returned as script index by pango_ot_info_find_script() if the script or a default script are not found, all other functions taking a script index essentially return if the input script index is this value, so no special handling is required by the user.

Since: 1.18


PANGO_OT_DEFAULT_LANGUAGE

#define PANGO_OT_DEFAULT_LANGUAGE		((guint) 0xFFFF)

This is used as the language index in pango_ot_info_find_feature() when the default language system of the script is desired.

It is also returned by pango_ot_info_find_language() if the requested language is not found, or the requested language tag was PANGO_OT_TAG_DEFAULT_LANGUAGE. The end result is that one can always call pango_ot_tag_from_language() followed by pango_ot_info_find_language() and pass the result to pango_ot_info_find_feature() without having to worry about falling back to default language system explicitly.

Since: 1.16


PANGO_OT_TAG_DEFAULT_LANGUAGE

#define PANGO_OT_TAG_DEFAULT_LANGUAGE		PANGO_OT_TAG_MAKE ('d', 'f', 'l', 't')

This is a PangoOTTag representing a special language tag 'dflt'. It is returned as language tag by pango_ot_tag_from_language() if the requested language is not found. It is safe to pass this value to pango_ot_info_find_language() as that function falls back to returning default language-system if the requested language tag is not found.

Since: 1.18


PANGO_OT_TAG_DEFAULT_SCRIPT

#define PANGO_OT_TAG_DEFAULT_SCRIPT		PANGO_OT_TAG_MAKE ('D', 'F', 'L', 'T')

This is a PangoOTTag representing the special script tag 'DFLT'. It is returned as script tag by pango_ot_tag_from_script() if the requested script is not found.

Since: 1.18

© manpagez.com 2000-2017
Individual documents may contain additional copyright information.