New API: hb_ot_layout_script_select_language2()

Variant that outputs chosen_language.

Not sure why the original API didn't have this. The script
counterpart has.
This commit is contained in:
Behdad Esfahbod 2023-01-20 09:28:59 -07:00
parent 2fd8e36ea5
commit edec8946ed
3 changed files with 78 additions and 22 deletions

View File

@ -640,6 +640,7 @@ hb_ot_layout_lookup_would_substitute
hb_ot_layout_script_find_language hb_ot_layout_script_find_language
hb_ot_layout_script_get_language_tags hb_ot_layout_script_get_language_tags
hb_ot_layout_script_select_language hb_ot_layout_script_select_language
hb_ot_layout_script_select_language2
hb_ot_layout_table_find_feature_variations hb_ot_layout_table_find_feature_variations
hb_ot_layout_table_get_feature_tags hb_ot_layout_table_get_feature_tags
hb_ot_layout_table_get_script_tags hb_ot_layout_table_get_script_tags

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@ -500,8 +500,8 @@ hb_ot_layout_table_find_script (hb_face_t *face,
* @face: #hb_face_t to work upon * @face: #hb_face_t to work upon
* @table_tag: #HB_OT_TAG_GSUB or #HB_OT_TAG_GPOS * @table_tag: #HB_OT_TAG_GSUB or #HB_OT_TAG_GPOS
* @script_tags: Array of #hb_tag_t script tags * @script_tags: Array of #hb_tag_t script tags
* @script_index: (out): The index of the requested script tag * @script_index: (out): The index of the chosen script
* @chosen_script: (out): #hb_tag_t of the script tag requested * @chosen_script: (out): #hb_tag_t of the chosen script
* *
* Deprecated since 2.0.0 * Deprecated since 2.0.0
**/ **/
@ -531,8 +531,8 @@ hb_ot_layout_table_choose_script (hb_face_t *face,
* *
* If the table does not have any of the requested scripts, then `DFLT`, * If the table does not have any of the requested scripts, then `DFLT`,
* `dflt`, and `latn` tags are tried in that order. If the table still does not * `dflt`, and `latn` tags are tried in that order. If the table still does not
* have any of these scripts, @script_index and @chosen_script are set to * have any of these scripts, @script_index is set to
* #HB_OT_LAYOUT_NO_SCRIPT_INDEX. * #HB_OT_LAYOUT_NO_SCRIPT_INDEX and @chosen_script is set to #HB_TAG_NONE.
* *
* Return value: * Return value:
* `true` if one of the requested scripts is selected, `false` if a fallback * `true` if one of the requested scripts is selected, `false` if a fallback
@ -726,6 +726,66 @@ hb_ot_layout_script_find_language (hb_face_t *face,
#endif #endif
/**
* hb_ot_layout_script_select_language2:
* @face: #hb_face_t to work upon
* @table_tag: #HB_OT_TAG_GSUB or #HB_OT_TAG_GPOS
* @script_index: The index of the requested script tag
* @language_count: The number of languages in the specified script
* @language_tags: The array of language tags
* @language_index: (out): The index of the chosen language
* @chosen_language: (out): #hb_tag_t of the chosen language
*
* Fetches the index of the first language tag fom @language_tags that is present
* in the specified face's GSUB or GPOS table, underneath the specified script
* index.
*
* If none of the given language tags is found, `false` is returned and
* @language_index is set to #HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX and
* @chosen_language is set to #HB_TAG_NONE.
*
* Return value: `true` if one of the given language tags is found, `false` otherwise
*
* Since: REPLACEME
**/
hb_bool_t
hb_ot_layout_script_select_language2 (hb_face_t *face,
hb_tag_t table_tag,
unsigned int script_index,
unsigned int language_count,
const hb_tag_t *language_tags,
unsigned int *language_index /* OUT */,
hb_tag_t *chosen_language /* OUT */)
{
static_assert ((OT::Index::NOT_FOUND_INDEX == HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX), "");
const OT::Script &s = get_gsubgpos_table (face, table_tag).get_script (script_index);
unsigned int i;
for (i = 0; i < language_count; i++)
{
if (s.find_lang_sys_index (language_tags[i], language_index))
{
if (chosen_language)
*chosen_language = language_tags[i];
return true;
}
}
/* try finding 'dflt' */
if (s.find_lang_sys_index (HB_OT_TAG_DEFAULT_LANGUAGE, language_index))
{
if (chosen_language)
*chosen_language = HB_OT_TAG_DEFAULT_LANGUAGE;
return false;
}
if (language_index)
*language_index = HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX;
if (chosen_language)
*chosen_language = HB_TAG_NONE;
return false;
}
/** /**
* hb_ot_layout_script_select_language: * hb_ot_layout_script_select_language:
* @face: #hb_face_t to work upon * @face: #hb_face_t to work upon
@ -754,26 +814,12 @@ hb_ot_layout_script_select_language (hb_face_t *face,
const hb_tag_t *language_tags, const hb_tag_t *language_tags,
unsigned int *language_index /* OUT */) unsigned int *language_index /* OUT */)
{ {
static_assert ((OT::Index::NOT_FOUND_INDEX == HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX), ""); return hb_ot_layout_script_select_language2 (face, table_tag,
const OT::Script &s = get_gsubgpos_table (face, table_tag).get_script (script_index); script_index,
unsigned int i; language_count, language_tags,
language_index, nullptr);
for (i = 0; i < language_count; i++)
{
if (s.find_lang_sys_index (language_tags[i], language_index))
return true;
}
/* try finding 'dflt' */
if (s.find_lang_sys_index (HB_OT_TAG_DEFAULT_LANGUAGE, language_index))
return false;
if (language_index)
*language_index = HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX;
return false;
} }
/** /**
* hb_ot_layout_language_get_required_feature_index: * hb_ot_layout_language_get_required_feature_index:
* @face: #hb_face_t to work upon * @face: #hb_face_t to work upon

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@ -254,6 +254,15 @@ hb_ot_layout_script_select_language (hb_face_t *face,
const hb_tag_t *language_tags, const hb_tag_t *language_tags,
unsigned int *language_index /* OUT */); unsigned int *language_index /* OUT */);
HB_EXTERN hb_bool_t
hb_ot_layout_script_select_language2 (hb_face_t *face,
hb_tag_t table_tag,
unsigned int script_index,
unsigned int language_count,
const hb_tag_t *language_tags,
unsigned int *language_index /* OUT */,
hb_tag_t *chosen_language /* OUT */);
HB_EXTERN hb_bool_t HB_EXTERN hb_bool_t
hb_ot_layout_language_get_required_feature_index (hb_face_t *face, hb_ot_layout_language_get_required_feature_index (hb_face_t *face,
hb_tag_t table_tag, hb_tag_t table_tag,