diff options
Diffstat (limited to 'pango/pango-ot-info.c')
| -rw-r--r-- | pango/pango-ot-info.c | 119 |
1 files changed, 111 insertions, 8 deletions
diff --git a/pango/pango-ot-info.c b/pango/pango-ot-info.c index 5f3ff33f..75d14e2b 100644 --- a/pango/pango-ot-info.c +++ b/pango/pango-ot-info.c @@ -404,7 +404,15 @@ get_tables (PangoOTInfo *info, * @script_tag: the tag of the script to find. * @script_index: location to store the index of the script, or %NULL. * - * Finds the index of a script. + * Finds the index of a script. If not found, tries to find the 'DFLT' + * and then 'dflt' scripts and return the index of that in @script_index. + * If none of those is found either, %PANGO_OT_NO_SCRIPT is placed in + * @script_index. + * + * All other functions taking an input script_index parameter know + * how to handle %PANGO_OT_NO_SCRIPT, so one can ignore the return + * value of this function completely and proceed, to enjoy the automatic + * fallback to the 'DFLT'/'dflt' script. * * Return value: %TRUE if the script was found. **/ @@ -417,6 +425,9 @@ pango_ot_info_find_script (PangoOTInfo *info, HB_ScriptList *script_list; int i; + if (script_index) + *script_index = PANGO_OT_NO_SCRIPT; + g_return_val_if_fail (PANGO_IS_OT_INFO (info), FALSE); if (!get_tables (info, table_type, &script_list, NULL)) @@ -433,6 +444,34 @@ pango_ot_info_find_script (PangoOTInfo *info, } } + /* try finding 'DFLT' */ + script_tag = PANGO_OT_TAG_DEFAULT_SCRIPT; + + for (i=0; i < script_list->ScriptCount; i++) + { + if (script_list->ScriptRecord[i].ScriptTag == script_tag) + { + if (script_index) + *script_index = i; + + return FALSE; + } + } + + /* try with 'dflt'; MS site has had typos and many fonts use it now :( */ + script_tag = FT_MAKE_TAG ('d', 'f', 'l', 't'); + + for (i=0; i < script_list->ScriptCount; i++) + { + if (script_list->ScriptRecord[i].ScriptTag == script_tag) + { + if (script_index) + *script_index = i; + + return FALSE; + } + } + return FALSE; } @@ -447,6 +486,13 @@ pango_ot_info_find_script (PangoOTInfo *info, * the language, or %NULL. * * Finds the index of a language and its required feature index. + * If the language is not found, sets @language_index to + * PANGO_OT_DEFAULT_LANGUAGE and the required feature of the default language + * system is returned in required_feature_index. For best compatibility with + * some fonts, also searches the language system tag 'dflt' before falling + * back to the default language system, but that is transparent to the user. + * The user can simply ignore the return value of this function to + * automatically fall back to the default language system. * * Return value: %TRUE if the language was found. **/ @@ -462,8 +508,16 @@ pango_ot_info_find_language (PangoOTInfo *info, HB_Script *script; int i; + if (language_index) + *language_index = PANGO_OT_DEFAULT_LANGUAGE; + if (required_feature_index) + *required_feature_index = PANGO_OT_NO_FEATURE; + g_return_val_if_fail (PANGO_IS_OT_INFO (info), FALSE); + if (script_index == PANGO_OT_NO_SCRIPT) + return FALSE; + if (!get_tables (info, table_type, &script_list, NULL)) return FALSE; @@ -483,6 +537,27 @@ pango_ot_info_find_language (PangoOTInfo *info, } } + /* try with 'dflt'; MS site has had typos and many fonts use it now :( */ + language_tag = FT_MAKE_TAG ('d', 'f', 'l', 't'); + + for (i = 0; i < script->LangSysCount; i++) + { + if (script->LangSysRecord[i].LangSysTag == language_tag) + { + if (language_index) + *language_index = i; + if (required_feature_index) + *required_feature_index = script->LangSysRecord[i].LangSys.ReqFeatureIndex; + return FALSE; + } + } + + /* DefaultLangSys */ + if (language_index) + *language_index = PANGO_OT_DEFAULT_LANGUAGE; + if (required_feature_index) + *required_feature_index = script->DefaultLangSys.ReqFeatureIndex; + return FALSE; } @@ -496,7 +571,15 @@ pango_ot_info_find_language (PangoOTInfo *info, * or %PANGO_OT_DEFAULT_LANGUAGE to use the default language of the script. * @feature_index: location to store the index of the feature, or %NULL. * - * Finds the index of a feature. + * Finds the index of a feature. If the feature is not found, sets + * @feature_index to PANGO_OT_NO_FEATURE, which is safe to pass to + * pango_ot_ruleset_add_feature() and similar functions. + * + * In the future, this may set @feature_index to an special value that if used + * in pango_ot_ruleset_add_feature() will ask Pango to synthesize the + * requested feature based on Unicode properties and data. However, this + * function will still return %FALSE in those cases. So, users may want to + * ignore the return value of this function in certain cases. * * Return value: %TRUE if the feature was found. **/ @@ -515,8 +598,14 @@ pango_ot_info_find_feature (PangoOTInfo *info, int i; + if (feature_index) + *feature_index = PANGO_OT_NO_FEATURE; + g_return_val_if_fail (PANGO_IS_OT_INFO (info), FALSE); + if (script_index == PANGO_OT_NO_SCRIPT) + return FALSE; + if (!get_tables (info, table_type, &script_list, &feature_list)) return FALSE; @@ -555,8 +644,8 @@ pango_ot_info_find_feature (PangoOTInfo *info, * * Obtains the list of available scripts. * - * Return value: a newly-allocated array containing the tags of the - * available scripts. + * Return value: a newly-allocated zero-terminated array containing the tags of the + * available scripts that should be freed using g_free(). **/ PangoOTTag * pango_ot_info_list_scripts (PangoOTInfo *info, @@ -590,8 +679,8 @@ pango_ot_info_list_scripts (PangoOTInfo *info, * * Obtains the list of available languages for a given script. * - * Return value: a newly-allocated array containing the tags of the - * available languages. + * Return value: a newly-allocated zero-terminated array containing the tags of the + * available languages that should be freed using g_free(). **/ PangoOTTag * pango_ot_info_list_languages (PangoOTInfo *info, @@ -606,6 +695,13 @@ pango_ot_info_list_languages (PangoOTInfo *info, g_return_val_if_fail (PANGO_IS_OT_INFO (info), NULL); + if (script_index == PANGO_OT_NO_SCRIPT) + { + result = g_new (PangoOTTag, 1); + result[0] = 0; + return result; + } + if (!get_tables (info, table_type, &script_list, NULL)) return NULL; @@ -635,8 +731,8 @@ pango_ot_info_list_languages (PangoOTInfo *info, * * Obtains the list of features for the given language of the given script. * - * Return value: a newly-allocated array containing the tags of the - * available features. + * Return value: a newly-allocated zero-terminated array containing the tags of the + * available features that should be freed using g_free(). **/ PangoOTTag * pango_ot_info_list_features (PangoOTInfo *info, @@ -656,6 +752,13 @@ pango_ot_info_list_features (PangoOTInfo *info, g_return_val_if_fail (PANGO_IS_OT_INFO (info), NULL); + if (script_index == PANGO_OT_NO_SCRIPT) + { + result = g_new (PangoOTTag, 1); + result[0] = 0; + return result; + } + if (!get_tables (info, table_type, &script_list, &feature_list)) return NULL; |