Struct

Pango.GlyphItemIter

Description [src]

struct PangoGlyphItemIter {
  PangoGlyphItem* glyph_item;
  const gchar* text;
  int start_glyph;
  int start_index;
  int start_char;
  int end_glyph;
  int end_index;
  int end_char;
}

A PangoGlyphItemIter is an iterator over the clusters in a PangoGlyphItem.

The forward direction of the iterator is the logical direction of text. That is, with increasing start_index and start_char values. If glyph_item is right-to-left (that is, if glyph_item->item->analysis.level is odd), then start_glyph decreases as the iterator moves forward. Moreover, in right-to-left cases, start_glyph is greater than end_glyph.

An iterator should be initialized using either pango_glyph_item_iter_init_start() or pango_glyph_item_iter_init_end(), for forward and backward iteration respectively, and walked over using any desired mixture of pango_glyph_item_iter_next_cluster() and pango_glyph_item_iter_prev_cluster().

A common idiom for doing a forward iteration over the clusters is:

PangoGlyphItemIter cluster_iter;
gboolean have_cluster;

for (have_cluster = pango_glyph_item_iter_init_start (&cluster_iter,
                                                      glyph_item, text);
     have_cluster;
     have_cluster = pango_glyph_item_iter_next_cluster (&cluster_iter))
{
  ...
}

Note that text is the start of the text for layout, which is then indexed by glyph_item->item->offset to get to the text of glyph_item. The start_index and end_index values can directly index into text. The start_glyph, end_glyph, start_char, and end_char values however are zero-based for the glyph_item. For each cluster, the item pointed at by the start variables is included in the cluster while the one pointed at by end variables is not.

None of the members of a PangoGlyphItemIter should be modified manually.

Structure members
glyph_item No description available.
text No description available.
start_glyph No description available.
start_index No description available.
start_char No description available.
end_glyph No description available.
end_index No description available.
end_char No description available.

Instance methods

pango_glyph_item_iter_copy

Make a shallow copy of an existing PangoGlyphItemIter structure.

pango_glyph_item_iter_free

Frees a PangoGlyphItemIter.

pango_glyph_item_iter_init_end

Initializes a PangoGlyphItemIter structure to point to the last cluster in a glyph item.

pango_glyph_item_iter_init_start

Initializes a PangoGlyphItemIter structure to point to the first cluster in a glyph item.

pango_glyph_item_iter_next_cluster

Advances the iterator to the next cluster in the glyph item.

pango_glyph_item_iter_prev_cluster

Moves the iterator to the preceding cluster in the glyph item. See PangoGlyphItemIter for details of cluster orders.