/* Pango * pango-ot-info.c: Store tables for OpenType * * Copyright (C) 2000 Red Hat Software * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. */ /** * SECTION:opentype * @short_description:Obtaining information from OpenType tables * @title:OpenType Font Handling * @stability:Unstable * * Functions and macros in this section are used to implement the OpenType Layout * features and algorithms. These are mostly useful when writing Fontconfig-based * shaping engines */ #include "config.h" #include "pango-ot-private.h" static void pango_ot_info_finalize (GObject *object); G_DEFINE_TYPE (PangoOTInfo, pango_ot_info, G_TYPE_OBJECT); static void pango_ot_info_init (PangoOTInfo *self) { } static void pango_ot_info_class_init (PangoOTInfoClass *klass) { GObjectClass *object_class = G_OBJECT_CLASS (klass); object_class->finalize = pango_ot_info_finalize; } static void pango_ot_info_finalize (GObject *object) { PangoOTInfo *info = PANGO_OT_INFO (object); if (info->hb_face) hb_face_destroy (info->hb_face); G_OBJECT_CLASS (pango_ot_info_parent_class)->finalize (object); } static void pango_ot_info_finalizer (void *object) { FT_Face face = object; PangoOTInfo *info = face->generic.data; info->face = NULL; g_object_unref (info); } /** * pango_ot_info_get: * @face: a FT_Face. * * Returns the #PangoOTInfo structure for the given FreeType font face. * * Return value: the #PangoOTInfo for @face. This object will have * the same lifetime as @face. * * Since: 1.2 **/ PangoOTInfo * pango_ot_info_get (FT_Face face) { PangoOTInfo *info; if (G_UNLIKELY (!face)) return NULL; if (G_LIKELY (face->generic.data && face->generic.finalizer == pango_ot_info_finalizer)) return face->generic.data; else { if (face->generic.finalizer) face->generic.finalizer (face); info = face->generic.data = g_object_new (PANGO_TYPE_OT_INFO, NULL); face->generic.finalizer = pango_ot_info_finalizer; info->face = face; info->hb_face = hb_ft_face_create (face, NULL); } return info; } static hb_tag_t get_hb_table_type (PangoOTTableType table_type) { switch (table_type) { case PANGO_OT_TABLE_GSUB: return HB_OT_TAG_GSUB; case PANGO_OT_TABLE_GPOS: return HB_OT_TAG_GPOS; default: return HB_TAG_NONE; } } /** * pango_ot_info_find_script: * @info: a #PangoOTInfo. * @table_type: the table type to obtain information about. * @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. 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. **/ gboolean pango_ot_info_find_script (PangoOTInfo *info, PangoOTTableType table_type, PangoOTTag script_tag, guint *script_index) { hb_tag_t tt = get_hb_table_type (table_type); return hb_ot_layout_table_find_script (info->hb_face, tt, script_tag, script_index); } /** * pango_ot_info_find_language: * @info: a #PangoOTInfo. * @table_type: the table type to obtain information about. * @script_index: the index of the script whose languages are searched. * @language_tag: the tag of the language to find. * @language_index: location to store the index of the language, or %NULL. * @required_feature_index: location to store the required feature index of * 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. **/ gboolean pango_ot_info_find_language (PangoOTInfo *info, PangoOTTableType table_type, guint script_index, PangoOTTag language_tag, guint *language_index, guint *required_feature_index) { gboolean ret; unsigned l_index; hb_tag_t tt = get_hb_table_type (table_type); ret = hb_ot_layout_script_find_language (info->hb_face, tt, script_index, language_tag, &l_index); if (language_index) *language_index = l_index; hb_ot_layout_language_get_required_feature (info->hb_face, tt, script_index, l_index, required_feature_index, NULL); return ret; } /** * pango_ot_info_find_feature: * @info: a #PangoOTInfo. * @table_type: the table type to obtain information about. * @feature_tag: the tag of the feature to find. * @script_index: the index of the script. * @language_index: the index of the language whose features are searched, * 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. 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. **/ gboolean pango_ot_info_find_feature (PangoOTInfo *info, PangoOTTableType table_type, PangoOTTag feature_tag, guint script_index, guint language_index, guint *feature_index) { hb_tag_t tt = get_hb_table_type (table_type); return hb_ot_layout_language_find_feature (info->hb_face, tt, script_index, language_index, feature_tag, feature_index); } /** * pango_ot_info_list_scripts: * @info: a #PangoOTInfo. * @table_type: the table type to obtain information about. * * Obtains the list of available scripts. * * Return value: a newly-allocated zero-terminated array containing the tags of the * available scripts. Should be freed using g_free(). **/ PangoOTTag * pango_ot_info_list_scripts (PangoOTInfo *info, PangoOTTableType table_type) { hb_tag_t tt = get_hb_table_type (table_type); PangoOTTag *result; unsigned int count; count = hb_ot_layout_table_get_script_tags (info->hb_face, tt, 0, NULL, NULL); result = g_new (PangoOTTag, count + 1); hb_ot_layout_table_get_script_tags (info->hb_face, tt, 0, &count, result); result[count] = 0; return result; } /** * pango_ot_info_list_languages: * @info: a #PangoOTInfo. * @table_type: the table type to obtain information about. * @script_index: the index of the script to list languages for. * @language_tag: unused parameter. * * Obtains the list of available languages for a given script. * * Return value: a newly-allocated zero-terminated array containing the tags of the * available languages. Should be freed using g_free(). **/ PangoOTTag * pango_ot_info_list_languages (PangoOTInfo *info, PangoOTTableType table_type, guint script_index, PangoOTTag language_tag G_GNUC_UNUSED) { hb_tag_t tt = get_hb_table_type (table_type); PangoOTTag *result; unsigned int count; count = hb_ot_layout_script_get_language_tags (info->hb_face, tt, script_index, 0, NULL, NULL); result = g_new (PangoOTTag, count + 1); hb_ot_layout_script_get_language_tags (info->hb_face, tt, script_index, 0, &count, result); result[count] = 0; return result; } /** * pango_ot_info_list_features: * @info: a #PangoOTInfo. * @table_type: the table type to obtain information about. * @tag: unused parameter. * @script_index: the index of the script to obtain information about. * @language_index: the index of the language to list features for, or * %PANGO_OT_DEFAULT_LANGUAGE, to list features for the default * language of the script. * * Obtains the list of features for the given language of the given script. * * Return value: a newly-allocated zero-terminated array containing the tags of the * available features. Should be freed using g_free(). **/ PangoOTTag * pango_ot_info_list_features (PangoOTInfo *info, PangoOTTableType table_type, PangoOTTag tag G_GNUC_UNUSED, guint script_index, guint language_index) { hb_tag_t tt = get_hb_table_type (table_type); PangoOTTag *result; unsigned int count; count = hb_ot_layout_language_get_feature_tags (info->hb_face, tt, script_index, language_index, 0, NULL, NULL); result = g_new (PangoOTTag, count + 1); hb_ot_layout_language_get_feature_tags (info->hb_face, tt, script_index, language_index, 0, &count, result); result[count] = 0; return result; }