pango_itemize ()

GList *
pango_itemize (PangoContext *context,
               const char *text,
               int start_index,
               int length,
               PangoAttrList *attrs,
               PangoAttrIterator *cached_iter);

Breaks a piece of text into segments with consistent directional level and shaping engine. Each byte of text will be contained in exactly one of the items in the returned list; the generated list of items will be in logical order (the start offsets of the items are ascending).

cached_iter should be an iterator over attrs currently positioned at a range before or containing start_index ; cached_iter will be advanced to the range covering the position just after start_index + length . (i.e. if itemizing in a loop, just keep passing in the same cached_iter ).

pango_itemize_with_base_dir ()

GList *
pango_itemize_with_base_dir (PangoContext *context,
                             PangoDirection base_dir,
                             const char *text,
                             int start_index,
                             int length,
                             PangoAttrList *attrs,
                             PangoAttrIterator *cached_iter);

Like pango_itemize(), but the base direction to use when computing bidirectional levels (see pango_context_set_base_dir()), is specified explicitly rather than gotten from the PangoContext.

Since: 1.4

pango_item_free ()

void
pango_item_free (PangoItem *item);

Free a PangoItem and all associated memory.

pango_item_copy ()

PangoItem *
pango_item_copy (PangoItem *item);

Copy an existing PangoItem structure.

pango_item_new ()

PangoItem *
pango_item_new (void);

Creates a new PangoItem structure initialized to default values.

pango_item_split ()

PangoItem *
pango_item_split (PangoItem *orig,
                  int split_index,
                  int split_offset);

Modifies orig to cover only the text after split_index , and returns a new item that covers the text before split_index that used to be in orig . You can think of split_index as the length of the returned item. split_index may not be 0, and it may not be greater than or equal to the length of orig (that is, there must be at least one byte assigned to each item, you can't create a zero-length item). split_offset is the length of the first item in chars, and must be provided because the text used to generate the item isn't available, so pango_item_split() can't count the char length of the split items itself.

pango_item_apply_attrs ()

void
pango_item_apply_attrs (PangoItem *item,
                        PangoAttrIterator *iter);

Add attributes to a PangoItem. The idea is that you have attributes that don't affect itemization, such as font features, so you filter them out using pango_attr_list_filter(), itemize your text, then reapply the attributes to the resulting items using this function.

The iter should be positioned before the range of the item, and will be advanced past it. This function is meant to be called in a loop over the items resulting from itemization, while passing the iter to each call.

Since: 1.44

pango_reorder_items ()

GList *
pango_reorder_items (GList *logical_items);

From a list of items in logical order and the associated directional levels, produce a list in visual order. The original list is unmodified.

pango_break ()

void
pango_break (const gchar *text,
             int length,
             PangoAnalysis *analysis,
             PangoLogAttr *attrs,
             int attrs_len);

Determines possible line, word, and character breaks for a string of Unicode text with a single analysis. For most purposes you may want to use pango_get_log_attrs().

pango_get_log_attrs ()

void
pango_get_log_attrs (const char *text,
                     int length,
                     int level,
                     PangoLanguage *language,
                     PangoLogAttr *log_attrs,
                     int attrs_len);

Computes a PangoLogAttr for each character in text . The log_attrs array must have one PangoLogAttr for each position in text ; if text contains N characters, it has N+1 positions, including the last position at the end of the text. text should be an entire paragraph; logical attributes can't be computed without context (for example you need to see spaces on either side of a word to know the word is a word).

pango_find_paragraph_boundary ()

void
pango_find_paragraph_boundary (const gchar *text,
                               gint length,
                               gint *paragraph_delimiter_index,
                               gint *next_paragraph_start);

Locates a paragraph boundary in text . A boundary is caused by delimiter characters, such as a newline, carriage return, carriage return-newline pair, or Unicode paragraph separator character. The index of the run of delimiters is returned in paragraph_delimiter_index . The index of the start of the paragraph (index after all delimiters) is stored in next_paragraph_start .

If no delimiters are found, both paragraph_delimiter_index and next_paragraph_start are filled with the length of text (an index one off the end).

pango_default_break ()

void
pango_default_break (const gchar *text,
                     int length,
                     PangoAnalysis *analysis,
                     PangoLogAttr *attrs,
                     int attrs_len);

This is the default break algorithm. It applies Unicode rules without language-specific tailoring, therefore the analyis argument is unused and can be NULL.

See pango_tailor_break() for language-specific breaks.

pango_tailor_break ()

void
pango_tailor_break (const char *text,
                    int length,
                    PangoAnalysis *analysis,
                    int offset,
                    PangoLogAttr *log_attrs,
                    int log_attrs_len);

Apply language-specific tailoring to the breaks in log_attrs , which are assumed to have been produced by pango_default_break().

If offset is not -1, it is used to apply attributes from analysis that are relevant to line breaking.

Since: 1.44

pango_shape ()

void
pango_shape (const char *text,
             int length,
             const PangoAnalysis *analysis,
             PangoGlyphString *glyphs);

Given a segment of text and the corresponding PangoAnalysis structure returned from pango_itemize(), convert the characters into glyphs. You may also pass in only a substring of the item from pango_itemize().

It is recommended that you use pango_shape_full() instead, since that API allows for shaping interaction happening across text item boundaries.

Note that the extra attributes in the analyis that is returned from pango_itemize() have indices that are relative to the entire paragraph, so you need to subtract the item offset from their indices before calling pango_shape().

pango_shape_full ()

void
pango_shape_full (const char *item_text,
                  int item_length,
                  const char *paragraph_text,
                  int paragraph_length,
                  const PangoAnalysis *analysis,
                  PangoGlyphString *glyphs);

Given a segment of text and the corresponding PangoAnalysis structure returned from pango_itemize(), convert the characters into glyphs. You may also pass in only a substring of the item from pango_itemize().

This is similar to pango_shape(), except it also can optionally take the full paragraph text as input, which will then be used to perform certain cross-item shaping interactions. If you have access to the broader text of which item_text is part of, provide the broader text as paragraph_text . If paragraph_text is NULL, item text is used instead.

Note that the extra attributes in the analyis that is returned from pango_itemize() have indices that are relative to the entire paragraph, so you do not pass the full paragraph text as paragraph_text , you need to subtract the item offset from their indices before calling pango_shape_full().

Since: 1.32

pango_shape_with_flags ()

void
pango_shape_with_flags (const char *item_text,
                        int item_length,
                        const char *paragraph_text,
                        int paragraph_length,
                        const PangoAnalysis *analysis,
                        PangoGlyphString *glyphs,
                        PangoShapeFlags flags);

Given a segment of text and the corresponding PangoAnalysis structure returned from pango_itemize(), convert the characters into glyphs. You may also pass in only a substring of the item from pango_itemize().

This is similar to pango_shape_full(), except it also takes flags that can influence the shaping process.

Note that the extra attributes in the analyis that is returned from pango_itemize() have indices that are relative to the entire paragraph, so you do not pass the full paragraph text as paragraph_text , you need to subtract the item offset from their indices before calling pango_shape_with_flags().

Since: 1.44

struct PangoItem

struct PangoItem {
  gint offset;
  gint length;
  gint num_chars;
  PangoAnalysis analysis;
};

The PangoItem structure stores information about a segment of text.

struct PangoAnalysis

struct PangoAnalysis {
  PangoEngineShape *shape_engine;
  PangoEngineLang  *lang_engine;
  PangoFont *font;

  guint8 level;
  guint8 gravity;
  guint8 flags;

  guint8 script;
  PangoLanguage *language;

  GSList *extra_attrs;
};

The PangoAnalysis structure stores information about the properties of a segment of text.

PANGO_ANALYSIS_FLAG_CENTERED_BASELINE

#define PANGO_ANALYSIS_FLAG_CENTERED_BASELINE (1 << 0)

Whether the segment should be shifted to center around the baseline. Used in vertical writing directions mostly.

Since: 1.16

PANGO_ANALYSIS_FLAG_IS_ELLIPSIS

#define PANGO_ANALYSIS_FLAG_IS_ELLIPSIS (1 << 1)

This flag is used to mark runs that hold ellipsized text, in an ellipsized layout.

Since: 1.36.7

PANGO_ANALYSIS_FLAG_NEED_HYPHEN

#define PANGO_ANALYSIS_FLAG_NEED_HYPHEN (1 << 2)

This flag tells Pango to add a hyphen at the end of the run during shaping.

Since: 1.44

PangoLogAttr

typedef struct {
  guint is_line_break               : 1;
  guint is_mandatory_break          : 1;
  guint is_char_break               : 1;
  guint is_white                    : 1;
  guint is_cursor_position          : 1;
  guint is_word_start               : 1;
  guint is_word_end                 : 1;
  guint is_sentence_boundary        : 1;
  guint is_sentence_start           : 1;
  guint is_sentence_end             : 1;
  guint backspace_deletes_character : 1;
  guint is_expandable_space         : 1;
  guint is_word_boundary            : 1;
} PangoLogAttr;

The PangoLogAttr structure stores information about the attributes of a single character.

enum PangoShapeFlags

Flags influencing the shaping process. These can be passed to pango_shape_with_flags().