diff options
Diffstat (limited to 'pango/pango-attributes.c')
| -rw-r--r-- | pango/pango-attributes.c | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/pango/pango-attributes.c b/pango/pango-attributes.c index 85e5a240..f641e9ac 100644 --- a/pango/pango-attributes.c +++ b/pango/pango-attributes.c @@ -1599,6 +1599,48 @@ pango_attr_list_change (PangoAttrList *list, } /** + * pango_attr_list_apply_delta: + * @list: a #PangoAttrList + * @pos: the position of the change + * @remove: the number of removed bytes + * @add: the number of added bytes + * + * Update indices of attributes in @list for + * a change in the text they refer to. + * + * The change that this function applies is + * removing @remove bytes at position @pos + * and inserting @add bytes instead. + * + * Attributes start and end positions are updated + * if they are behind @pos + @remove. Positions + * that fall into the (@pos, @pos + @remove) range + * are not updated, since we don't know how the + * removed and added text affects them. + */ +void +pango_attr_list_apply_delta (PangoAttrList *list, + int pos, + int remove, + int add) +{ + GSList *l; + + for (l = list->attributes; l; l = l->next) + { + PangoAttribute *attr = l->data; + + if (attr->end_index < pos) + continue; + + if (attr->start_index >= pos + remove) + attr->start_index += add - remove; + if (attr->end_index >= pos + remove) + attr->end_index += add - remove; + } +} + +/** * pango_attr_list_splice: * @list: a #PangoAttrList * @other: another #PangoAttrList |