GlyphItemIter

Added in version 1.22.

class GlyphItemIter(*args, **kwargs)

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 init_start() or init_end(), for forward and backward iteration respectively, and walked over using any desired mixture of next_cluster() and 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.

Methods

class GlyphItemIter

free() → None

Frees a PangoGlyphItemIter.

Added in version 1.22.

init_end(glyph_item: GlyphItem, text: str) → bool

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

See PangoGlyphItemIter for details of cluster orders.

Added in version 1.22.

Parameters:

• glyph_item – the glyph item to iterate over

• text – text corresponding to the glyph item

init_start(glyph_item: GlyphItem, text: str) → bool

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

See PangoGlyphItemIter for details of cluster orders.

Added in version 1.22.

Parameters:

• glyph_item – the glyph item to iterate over

• text – text corresponding to the glyph item

next_cluster() → bool

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

See PangoGlyphItemIter for details of cluster orders.

Added in version 1.22.

prev_cluster() → bool

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

Added in version 1.22.

Fields

class GlyphItemIter

end_char

end_glyph

end_index

glyph_item

start_char

start_glyph

start_index

text