src/hb-ot-map.cc - platform/external/harfbuzz_ng - Git at Google

 /*
  * Copyright © 2009,2010  Red Hat, Inc.
  * Copyright © 2010,2011  Google, Inc.
  *
  *  This is part of HarfBuzz, a text shaping library.
  *
  * Permission is hereby granted, without written agreement and without
  * license or royalty fees, to use, copy, modify, and distribute this
  * software and its documentation for any purpose, provided that the
  * above copyright notice and the following two paragraphs appear in
  * all copies of this software.
  *
  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
  * DAMAGE.
  *
  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
  *
  * Red Hat Author(s): Behdad Esfahbod
  * Google Author(s): Behdad Esfahbod
  */

 #include "hb-ot-map-private.hh"


 void
 hb_ot_map_t::add_lookups (hb_face_t    *face,
 			  unsigned int  table_index,
 			  unsigned int  feature_index,
 			  hb_mask_t     mask)
 {
   unsigned int lookup_indices[32];
   unsigned int offset, len;

   offset = 0;
   do {
     len = ARRAY_LENGTH (lookup_indices);
     hb_ot_layout_feature_get_lookups (face,
 				      table_tags[table_index],
 				      feature_index,
 				      offset, &len,
 				      lookup_indices);

     for (unsigned int i = 0; i < len; i++) {
       hb_ot_map_t::lookup_map_t *lookup = lookups[table_index].push ();
       if (unlikely (!lookup))
         return;
       lookup->mask = mask;
       lookup->index = lookup_indices[i];
     }

     offset += len;
   } while (len == ARRAY_LENGTH (lookup_indices));
 }

 hb_ot_map_builder_t::hb_ot_map_builder_t (hb_face_t *face_,
 					  const hb_segment_properties_t *props_)
 {
   memset (this, 0, sizeof (*this));

   face = face_;
   props = *props_;


   /* Fetch script/language indices for GSUB/GPOS.  We need these later to skip
    * features not available in either table and not waste precious bits for them. */

   hb_tag_t script_tags[3] = {HB_TAG_NONE, HB_TAG_NONE, HB_TAG_NONE};
   hb_tag_t language_tag;

   hb_ot_tags_from_script (props.script, &script_tags[0], &script_tags[1]);
   language_tag = hb_ot_tag_from_language (props.language);

   for (unsigned int table_index = 0; table_index < 2; table_index++) {
     hb_tag_t table_tag = table_tags[table_index];
     found_script[table_index] = hb_ot_layout_table_choose_script (face, table_tag, script_tags, &script_index[table_index], &chosen_script[table_index]);
     hb_ot_layout_script_find_language (face, table_tag, script_index[table_index], language_tag, &language_index[table_index]);
   }
 }

 void hb_ot_map_builder_t::add_feature (hb_tag_t tag, unsigned int value, bool global, bool has_fallback)
 {
   feature_info_t *info = feature_infos.push();
   if (unlikely (!info)) return;
   info->tag = tag;
   info->seq = feature_infos.len;
   info->max_value = value;
   info->global = global;
   info->has_fallback = has_fallback;
   info->default_value = global ? value : 0;
   info->stage[0] = current_stage[0];
   info->stage[1] = current_stage[1];
 }

 /* Keep the next two functions in sync. */

 void hb_ot_map_t::substitute (const hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const
 {
   const unsigned int table_index = 0;
   unsigned int i = 0;

   for (unsigned int pause_index = 0; pause_index < pauses[table_index].len; pause_index++) {
     const pause_map_t *pause = &pauses[table_index][pause_index];
     for (; i < pause->num_lookups; i++)
       hb_ot_layout_substitute_lookup (font, buffer, lookups[table_index][i].index, lookups[table_index][i].mask);

     buffer->clear_output ();

     if (pause->callback)
       pause->callback (plan, font, buffer);
   }

   for (; i < lookups[table_index].len; i++)
     hb_ot_layout_substitute_lookup (font, buffer, lookups[table_index][i].index, lookups[table_index][i].mask);
 }

 void hb_ot_map_t::position (const hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const
 {
   const unsigned int table_index = 1;
   unsigned int i = 0;

   for (unsigned int pause_index = 0; pause_index < pauses[table_index].len; pause_index++) {
     const pause_map_t *pause = &pauses[table_index][pause_index];
     for (; i < pause->num_lookups; i++)
       hb_ot_layout_position_lookup (font, buffer, lookups[table_index][i].index, lookups[table_index][i].mask);

     if (pause->callback)
       pause->callback (plan, font, buffer);
   }

   for (; i < lookups[table_index].len; i++)
     hb_ot_layout_position_lookup (font, buffer, lookups[table_index][i].index, lookups[table_index][i].mask);
 }

 void hb_ot_map_t::collect_lookups (unsigned int table_index, hb_set_t *lookups_out) const
 {
   for (unsigned int i = 0; i < lookups[table_index].len; i++)
     hb_set_add (lookups_out, lookups[table_index][i].index);
 }

 void hb_ot_map_builder_t::add_pause (unsigned int table_index, hb_ot_map_t::pause_func_t pause_func)
 {
   pause_info_t *p = pauses[table_index].push ();
   if (likely (p)) {
     p->stage = current_stage[table_index];
     p->callback = pause_func;
   }

   current_stage[table_index]++;
 }

 void
 hb_ot_map_builder_t::compile (hb_ot_map_t &m)
 {
   m.global_mask = 1;

   for (unsigned int table_index = 0; table_index < 2; table_index++) {
     m.chosen_script[table_index] = chosen_script[table_index];
     m.found_script[table_index] = found_script[table_index];
   }

   if (!feature_infos.len)
     return;

   /* Sort features and merge duplicates */
   {
     feature_infos.sort ();
     unsigned int j = 0;
     for (unsigned int i = 1; i < feature_infos.len; i++)
       if (feature_infos[i].tag != feature_infos[j].tag)
 	feature_infos[++j] = feature_infos[i];
       else {
 	if (feature_infos[i].global) {
 	  feature_infos[j].global = true;
 	  feature_infos[j].max_value = feature_infos[i].max_value;
 	  feature_infos[j].default_value = feature_infos[i].default_value;
 	} else {
 	  feature_infos[j].global = false;
 	  feature_infos[j].max_value = MAX (feature_infos[j].max_value, feature_infos[i].max_value);
 	}
 	feature_infos[j].has_fallback = feature_infos[j].has_fallback || feature_infos[i].has_fallback;
 	feature_infos[j].stage[0] = MIN (feature_infos[j].stage[0], feature_infos[i].stage[0]);
 	feature_infos[j].stage[1] = MIN (feature_infos[j].stage[1], feature_infos[i].stage[1]);
 	/* Inherit default_value from j */
       }
     feature_infos.shrink (j + 1);
   }


   /* Allocate bits now */
   unsigned int next_bit = 1;
   for (unsigned int i = 0; i < feature_infos.len; i++) {
     const feature_info_t *info = &feature_infos[i];

     unsigned int bits_needed;

     if (info->global && info->max_value == 1)
       /* Uses the global bit */
       bits_needed = 0;
     else
       bits_needed = _hb_bit_storage (info->max_value);

     if (!info->max_value || next_bit + bits_needed > 8 * sizeof (hb_mask_t))
       continue; /* Feature disabled, or not enough bits. */


     bool found = false;
     unsigned int feature_index[2];
     for (unsigned int table_index = 0; table_index < 2; table_index++)
       found |= hb_ot_layout_language_find_feature (face,
 						   table_tags[table_index],
 						   script_index[table_index],
 						   language_index[table_index],
 						   info->tag,
 						   &feature_index[table_index]);
     if (!found && !info->has_fallback)
       continue;


     hb_ot_map_t::feature_map_t *map = m.features.push ();
     if (unlikely (!map))
       break;

     map->tag = info->tag;
     map->index[0] = feature_index[0];
     map->index[1] = feature_index[1];
     map->stage[0] = info->stage[0];
     map->stage[1] = info->stage[1];
     if (info->global && info->max_value == 1) {
       /* Uses the global bit */
       map->shift = 0;
       map->mask = 1;
     } else {
       map->shift = next_bit;
       map->mask = (1 << (next_bit + bits_needed)) - (1 << next_bit);
       next_bit += bits_needed;
       if (info->global)
 	m.global_mask |= (info->default_value << map->shift) & map->mask;
     }
     map->_1_mask = (1 << map->shift) & map->mask;
     map->needs_fallback = !found;

   }
   feature_infos.shrink (0); /* Done with these */


   add_gsub_pause (NULL);
   add_gpos_pause (NULL);

   for (unsigned int table_index = 0; table_index < 2; table_index++) {
     hb_tag_t table_tag = table_tags[table_index];

     /* Collect lookup indices for features */

     unsigned int required_feature_index;
     if (hb_ot_layout_language_get_required_feature_index (face,
 							  table_tag,
 							  script_index[table_index],
 							  language_index[table_index],
 							  &required_feature_index))
       m.add_lookups (face, table_index, required_feature_index, 1);

     unsigned int pause_index = 0;
     unsigned int last_num_lookups = 0;
     for (unsigned stage = 0; stage < current_stage[table_index]; stage++)
     {
       for (unsigned i = 0; i < m.features.len; i++)
         if (m.features[i].stage[table_index] == stage)
 	  m.add_lookups (face, table_index, m.features[i].index[table_index], m.features[i].mask);

       /* Sort lookups and merge duplicates */
       if (last_num_lookups < m.lookups[table_index].len)
       {
 	m.lookups[table_index].sort (last_num_lookups, m.lookups[table_index].len);

 	unsigned int j = last_num_lookups;
 	for (unsigned int i = j + 1; i < m.lookups[table_index].len; i++)
 	  if (m.lookups[table_index][i].index != m.lookups[table_index][j].index)
 	    m.lookups[table_index][++j] = m.lookups[table_index][i];
 	  else
 	    m.lookups[table_index][j].mask |= m.lookups[table_index][i].mask;
 	m.lookups[table_index].shrink (j + 1);
       }

       last_num_lookups = m.lookups[table_index].len;

       if (pause_index < pauses[table_index].len && pauses[table_index][pause_index].stage == stage) {
 	hb_ot_map_t::pause_map_t *pause_map = m.pauses[table_index].push ();
 	if (likely (pause_map)) {
 	  pause_map->num_lookups = last_num_lookups;
 	  pause_map->callback = pauses[table_index][pause_index].callback;
 	}

 	pause_index++;
       }
     }
   }
 }
	/*
	* Copyright © 2009,2010 Red Hat, Inc.
	* Copyright © 2010,2011 Google, Inc.
	*
	* This is part of HarfBuzz, a text shaping library.
	*
	* Permission is hereby granted, without written agreement and without
	* license or royalty fees, to use, copy, modify, and distribute this
	* software and its documentation for any purpose, provided that the
	* above copyright notice and the following two paragraphs appear in
	* all copies of this software.
	*
	* IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
	* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
	* ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
	* IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
	* DAMAGE.
	*
	* THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
	* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
	* FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
	* ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
	* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
	*
	* Red Hat Author(s): Behdad Esfahbod
	* Google Author(s): Behdad Esfahbod
	*/

	#include "hb-ot-map-private.hh"


	void
	hb_ot_map_t::add_lookups (hb_face_t *face,
	unsigned int table_index,
	unsigned int feature_index,
	hb_mask_t mask)
	{
	unsigned int lookup_indices[32];
	unsigned int offset, len;

	offset = 0;
	do {
	len = ARRAY_LENGTH (lookup_indices);
	hb_ot_layout_feature_get_lookups (face,
	table_tags[table_index],
	feature_index,
	offset, &len,
	lookup_indices);

	for (unsigned int i = 0; i < len; i++) {
	hb_ot_map_t::lookup_map_t *lookup = lookups[table_index].push ();
	if (unlikely (!lookup))
	return;
	lookup->mask = mask;
	lookup->index = lookup_indices[i];
	}

	offset += len;
	} while (len == ARRAY_LENGTH (lookup_indices));
	}

	hb_ot_map_builder_t::hb_ot_map_builder_t (hb_face_t *face_,
	const hb_segment_properties_t *props_)
	{
	memset (this, 0, sizeof (*this));

	face = face_;
	props = *props_;


	/* Fetch script/language indices for GSUB/GPOS. We need these later to skip
	* features not available in either table and not waste precious bits for them. */

	hb_tag_t script_tags[3] = {HB_TAG_NONE, HB_TAG_NONE, HB_TAG_NONE};
	hb_tag_t language_tag;

	hb_ot_tags_from_script (props.script, &script_tags[0], &script_tags[1]);
	language_tag = hb_ot_tag_from_language (props.language);

	for (unsigned int table_index = 0; table_index < 2; table_index++) {
	hb_tag_t table_tag = table_tags[table_index];
	found_script[table_index] = hb_ot_layout_table_choose_script (face, table_tag, script_tags, &script_index[table_index], &chosen_script[table_index]);
	hb_ot_layout_script_find_language (face, table_tag, script_index[table_index], language_tag, &language_index[table_index]);
	}
	}

	void hb_ot_map_builder_t::add_feature (hb_tag_t tag, unsigned int value, bool global, bool has_fallback)
	{
	feature_info_t *info = feature_infos.push();
	if (unlikely (!info)) return;
	info->tag = tag;
	info->seq = feature_infos.len;
	info->max_value = value;
	info->global = global;
	info->has_fallback = has_fallback;
	info->default_value = global ? value : 0;
	info->stage[0] = current_stage[0];
	info->stage[1] = current_stage[1];
	}

	/* Keep the next two functions in sync. */

	void hb_ot_map_t::substitute (const hb_ot_shape_plan_t plan, hb_font_t font, hb_buffer_t *buffer) const
	{
	const unsigned int table_index = 0;
	unsigned int i = 0;

	for (unsigned int pause_index = 0; pause_index < pauses[table_index].len; pause_index++) {
	const pause_map_t *pause = &pauses[table_index][pause_index];
	for (; i < pause->num_lookups; i++)
	hb_ot_layout_substitute_lookup (font, buffer, lookups[table_index][i].index, lookups[table_index][i].mask);

	buffer->clear_output ();

	if (pause->callback)
	pause->callback (plan, font, buffer);
	}

	for (; i < lookups[table_index].len; i++)
	hb_ot_layout_substitute_lookup (font, buffer, lookups[table_index][i].index, lookups[table_index][i].mask);
	}

	void hb_ot_map_t::position (const hb_ot_shape_plan_t plan, hb_font_t font, hb_buffer_t *buffer) const
	{
	const unsigned int table_index = 1;
	unsigned int i = 0;

	for (unsigned int pause_index = 0; pause_index < pauses[table_index].len; pause_index++) {
	const pause_map_t *pause = &pauses[table_index][pause_index];
	for (; i < pause->num_lookups; i++)
	hb_ot_layout_position_lookup (font, buffer, lookups[table_index][i].index, lookups[table_index][i].mask);

	if (pause->callback)
	pause->callback (plan, font, buffer);
	}

	for (; i < lookups[table_index].len; i++)
	hb_ot_layout_position_lookup (font, buffer, lookups[table_index][i].index, lookups[table_index][i].mask);
	}

	void hb_ot_map_t::collect_lookups (unsigned int table_index, hb_set_t *lookups_out) const
	{
	for (unsigned int i = 0; i < lookups[table_index].len; i++)
	hb_set_add (lookups_out, lookups[table_index][i].index);
	}

	void hb_ot_map_builder_t::add_pause (unsigned int table_index, hb_ot_map_t::pause_func_t pause_func)
	{
	pause_info_t *p = pauses[table_index].push ();
	if (likely (p)) {
	p->stage = current_stage[table_index];
	p->callback = pause_func;
	}

	current_stage[table_index]++;
	}

	void
	hb_ot_map_builder_t::compile (hb_ot_map_t &m)
	{
	m.global_mask = 1;

	for (unsigned int table_index = 0; table_index < 2; table_index++) {
	m.chosen_script[table_index] = chosen_script[table_index];
	m.found_script[table_index] = found_script[table_index];
	}

	if (!feature_infos.len)
	return;

	/* Sort features and merge duplicates */
	{
	feature_infos.sort ();
	unsigned int j = 0;
	for (unsigned int i = 1; i < feature_infos.len; i++)
	if (feature_infos[i].tag != feature_infos[j].tag)
	feature_infos[++j] = feature_infos[i];
	else {
	if (feature_infos[i].global) {
	feature_infos[j].global = true;
	feature_infos[j].max_value = feature_infos[i].max_value;
	feature_infos[j].default_value = feature_infos[i].default_value;
	} else {
	feature_infos[j].global = false;
	feature_infos[j].max_value = MAX (feature_infos[j].max_value, feature_infos[i].max_value);
	}
	feature_infos[j].has_fallback = feature_infos[j].has_fallback \|\| feature_infos[i].has_fallback;
	feature_infos[j].stage[0] = MIN (feature_infos[j].stage[0], feature_infos[i].stage[0]);
	feature_infos[j].stage[1] = MIN (feature_infos[j].stage[1], feature_infos[i].stage[1]);
	/* Inherit default_value from j */
	}
	feature_infos.shrink (j + 1);
	}


	/* Allocate bits now */
	unsigned int next_bit = 1;
	for (unsigned int i = 0; i < feature_infos.len; i++) {
	const feature_info_t *info = &feature_infos[i];

	unsigned int bits_needed;

	if (info->global && info->max_value == 1)
	/* Uses the global bit */
	bits_needed = 0;
	else
	bits_needed = _hb_bit_storage (info->max_value);

	if (!info->max_value \|\| next_bit + bits_needed > 8 * sizeof (hb_mask_t))
	continue; /* Feature disabled, or not enough bits. */


	bool found = false;
	unsigned int feature_index[2];
	for (unsigned int table_index = 0; table_index < 2; table_index++)
	found \|= hb_ot_layout_language_find_feature (face,
	table_tags[table_index],
	script_index[table_index],
	language_index[table_index],
	info->tag,
	&feature_index[table_index]);
	if (!found && !info->has_fallback)
	continue;


	hb_ot_map_t::feature_map_t *map = m.features.push ();
	if (unlikely (!map))
	break;

	map->tag = info->tag;
	map->index[0] = feature_index[0];
	map->index[1] = feature_index[1];
	map->stage[0] = info->stage[0];
	map->stage[1] = info->stage[1];
	if (info->global && info->max_value == 1) {
	/* Uses the global bit */
	map->shift = 0;
	map->mask = 1;
	} else {
	map->shift = next_bit;
	map->mask = (1 << (next_bit + bits_needed)) - (1 << next_bit);
	next_bit += bits_needed;
	if (info->global)
	m.global_mask \|= (info->default_value << map->shift) & map->mask;
	}
	map->_1_mask = (1 << map->shift) & map->mask;
	map->needs_fallback = !found;

	}
	feature_infos.shrink (0); /* Done with these */


	add_gsub_pause (NULL);
	add_gpos_pause (NULL);

	for (unsigned int table_index = 0; table_index < 2; table_index++) {
	hb_tag_t table_tag = table_tags[table_index];

	/* Collect lookup indices for features */

	unsigned int required_feature_index;
	if (hb_ot_layout_language_get_required_feature_index (face,
	table_tag,
	script_index[table_index],
	language_index[table_index],
	&required_feature_index))
	m.add_lookups (face, table_index, required_feature_index, 1);

	unsigned int pause_index = 0;
	unsigned int last_num_lookups = 0;
	for (unsigned stage = 0; stage < current_stage[table_index]; stage++)
	{
	for (unsigned i = 0; i < m.features.len; i++)
	if (m.features[i].stage[table_index] == stage)
	m.add_lookups (face, table_index, m.features[i].index[table_index], m.features[i].mask);

	/* Sort lookups and merge duplicates */
	if (last_num_lookups < m.lookups[table_index].len)
	{
	m.lookups[table_index].sort (last_num_lookups, m.lookups[table_index].len);

	unsigned int j = last_num_lookups;
	for (unsigned int i = j + 1; i < m.lookups[table_index].len; i++)
	if (m.lookups[table_index][i].index != m.lookups[table_index][j].index)
	m.lookups[table_index][++j] = m.lookups[table_index][i];
	else
	m.lookups[table_index][j].mask \|= m.lookups[table_index][i].mask;
	m.lookups[table_index].shrink (j + 1);
	}

	last_num_lookups = m.lookups[table_index].len;

	if (pause_index < pauses[table_index].len && pauses[table_index][pause_index].stage == stage) {
	hb_ot_map_t::pause_map_t *pause_map = m.pauses[table_index].push ();
	if (likely (pause_map)) {
	pause_map->num_lookups = last_num_lookups;
	pause_map->callback = pauses[table_index][pause_index].callback;
	}

	pause_index++;
	}
	}
	}
	}