pango-ot-info.c

GTK+-2.0源码之pango-1.15.6.tar.gz

      HB_GDEF gdef = pango_ot_info_get_gdef (info);

      info->loaded |= INFO_LOADED_GPOS;

      if (is_truetype (info->face))
	{
	  error = HB_Load_GPOS_Table (info->face, &info->gpos, gdef);

	  if (error && error != FT_Err_Table_Missing)
	    g_warning ("Error loading GPOS table %d", error);
	}
    }

  return info->gpos;
}

static gboolean
get_tables (PangoOTInfo      *info,
	    PangoOTTableType  table_type,
	    HB_ScriptList  **script_list,
	    HB_FeatureList **feature_list)
{
  if (table_type == PANGO_OT_TABLE_GSUB)
    {
      HB_GSUB gsub = pango_ot_info_get_gsub (info);

      if (!gsub)
	return FALSE;
      else
	{
	  if (script_list)
	    *script_list = &gsub->ScriptList;
	  if (feature_list)
	    *feature_list = &gsub->FeatureList;
	  return TRUE;
	}
    }
  else
    {
      HB_GPOS gpos = pango_ot_info_get_gpos (info);

      if (!gpos)
	return FALSE;
      else
	{
	  if (script_list)
	    *script_list = &gpos->ScriptList;
	  if (feature_list)
	    *feature_list = &gpos->FeatureList;
	  return TRUE;
	}
    }
}

/**
 * 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.
 *
 * 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_ScriptList *script_list;
  int i;

  g_return_val_if_fail (PANGO_IS_OT_INFO (info), FALSE);

  if (!get_tables (info, table_type, &script_list, NULL))
    return FALSE;

  for (i=0; i < script_list->ScriptCount; i++)
    {
      if (script_list->ScriptRecord[i].ScriptTag == script_tag)
	{
	  if (script_index)
	    *script_index = i;

	  return TRUE;
	}
    }

  return FALSE;
}

/**
 * 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.
 *
 * 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)
{
  HB_ScriptList *script_list;
  HB_Script *script;
  int i;

  g_return_val_if_fail (PANGO_IS_OT_INFO (info), FALSE);

  if (!get_tables (info, table_type, &script_list, NULL))
    return FALSE;

  g_return_val_if_fail (script_index < script_list->ScriptCount, FALSE);

  script = &script_list->ScriptRecord[script_index].Script;

  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 TRUE;
	}
    }

  return FALSE;
}

/**
 * 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.
 *
 * 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_ScriptList *script_list;
  HB_FeatureList *feature_list;
  HB_Script *script;
  HB_LangSys *lang_sys;

  int i;

  g_return_val_if_fail (PANGO_IS_OT_INFO (info), FALSE);

  if (!get_tables (info, table_type, &script_list, &feature_list))
    return FALSE;

  g_return_val_if_fail (script_index < script_list->ScriptCount, FALSE);

  script = &script_list->ScriptRecord[script_index].Script;

  if (language_index == PANGO_OT_DEFAULT_LANGUAGE)
    lang_sys = &script->DefaultLangSys;
  else
    {
      g_return_val_if_fail (language_index < script->LangSysCount, FALSE);
      lang_sys = &script->LangSysRecord[language_index].LangSys;
    }

  for (i = 0; i < lang_sys->FeatureCount; i++)
    {
      FT_UShort index = lang_sys->FeatureIndex[i];

      if (feature_list->FeatureRecord[index].FeatureTag == feature_tag)
	{
	  if (feature_index)
	    *feature_index = index;

	  return TRUE;
	}
    }

  return FALSE;
}

/**
 * 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 array containing the tags of the
 *   available scripts.
 **/
PangoOTTag *
pango_ot_info_list_scripts (PangoOTInfo      *info,
			    PangoOTTableType  table_type)
{
  PangoOTTag *result;
  HB_ScriptList *script_list;
  int i;

  g_return_val_if_fail (PANGO_IS_OT_INFO (info), NULL);

  if (!get_tables (info, table_type, &script_list, NULL))
    return NULL;

  result = g_new (PangoOTTag, script_list->ScriptCount + 1);

  for (i=0; i < script_list->ScriptCount; i++)
    result[i] = script_list->ScriptRecord[i].ScriptTag;

  result[i] = 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 array containing the tags of the
 *   available languages.
 **/
PangoOTTag *
pango_ot_info_list_languages (PangoOTInfo      *info,
			      PangoOTTableType  table_type,
			      guint             script_index,
			      PangoOTTag        language_tag G_GNUC_UNUSED)
{
  PangoOTTag *result;
  HB_ScriptList *script_list;
  HB_Script *script;
  int i;

  g_return_val_if_fail (PANGO_IS_OT_INFO (info), NULL);

  if (!get_tables (info, table_type, &script_list, NULL))
    return NULL;

  g_return_val_if_fail (script_index < script_list->ScriptCount, NULL);

  script = &script_list->ScriptRecord[script_index].Script;

  result = g_new (PangoOTTag, script->LangSysCount + 1);

  for (i = 0; i < script->LangSysCount; i++)
    result[i] = script->LangSysRecord[i].LangSysTag;

  result[i] = 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 array containing the tags of the
 * available features.
 **/
PangoOTTag *
pango_ot_info_list_features  (PangoOTInfo      *info,
			      PangoOTTableType  table_type,
			      PangoOTTag        tag G_GNUC_UNUSED,
			      guint             script_index,
			      guint             language_index)
{
  PangoOTTag *result;

  HB_ScriptList *script_list;
  HB_FeatureList *feature_list;
  HB_Script *script;
  HB_LangSys *lang_sys;

  int i;

  g_return_val_if_fail (PANGO_IS_OT_INFO (info), NULL);

  if (!get_tables (info, table_type, &script_list, &feature_list))
    return NULL;

  g_return_val_if_fail (script_index < script_list->ScriptCount, NULL);

  script = &script_list->ScriptRecord[script_index].Script;

  if (language_index == PANGO_OT_DEFAULT_LANGUAGE)
    lang_sys = &script->DefaultLangSys;
  else
    {
      g_return_val_if_fail (language_index < script->LangSysCount, NULL);
      lang_sys = &script->LangSysRecord[language_index].LangSys;
    }

  result = g_new (PangoOTTag, lang_sys->FeatureCount + 1);

  for (i = 0; i < lang_sys->FeatureCount; i++)
    {
      FT_UShort index = lang_sys->FeatureIndex[i];

      result[i] = feature_list->FeatureRecord[index].FeatureTag;
    }

  result[i] = 0;

  return result;
}