src/hb-aat-layout-feat-table.hh - third_party/harfbuzz - Git at Google

 /*
  * Copyright © 2018  Ebrahim Byagowi
  *
  *  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.
  */

 #ifndef HB_AAT_LAYOUT_FEAT_TABLE_HH
 #define HB_AAT_LAYOUT_FEAT_TABLE_HH

 #include "hb-aat-layout-common.hh"

 /*
  * feat -- Feature Name
  * https://developer.apple.com/fonts/TrueType-Reference-Manual/RM06/Chap6feat.html
  */
 #define HB_AAT_TAG_feat HB_TAG('f','e','a','t')


 namespace AAT {


 struct SettingName
 {
   friend struct FeatureName;

   int cmp (hb_aat_layout_feature_selector_t key) const
   { return (int) key - (int) setting; }

   hb_aat_layout_feature_selector_t get_selector () const
   { return (hb_aat_layout_feature_selector_t) (unsigned) setting; }

   hb_aat_layout_feature_selector_info_t get_info (hb_aat_layout_feature_selector_t default_selector) const
   {
     return {
       nameIndex,
       (hb_aat_layout_feature_selector_t) (unsigned int) setting,
       default_selector == HB_AAT_LAYOUT_FEATURE_SELECTOR_INVALID
 	? (hb_aat_layout_feature_selector_t) (setting + 1)
 	: default_selector,
       0
     };
   }

   bool sanitize (hb_sanitize_context_t *c) const
   {
     TRACE_SANITIZE (this);
     return_trace (likely (c->check_struct (this)));
   }

   protected:
   HBUINT16	setting;	/* The setting. */
   NameID	nameIndex;	/* The name table index for the setting's name. */
   public:
   DEFINE_SIZE_STATIC (4);
 };
 DECLARE_NULL_NAMESPACE_BYTES (AAT, SettingName);

 struct feat;

 struct FeatureName
 {
   int cmp (hb_aat_layout_feature_type_t key) const
   { return (int) key - (int) feature; }

   enum {
     Exclusive	= 0x8000,	/* If set, the feature settings are mutually exclusive. */
     NotDefault	= 0x4000,	/* If clear, then the setting with an index of 0 in
 				 * the setting name array for this feature should
 				 * be taken as the default for the feature
 				 * (if one is required). If set, then bits 0-15 of this
 				 * featureFlags field contain the index of the setting
 				 * which is to be taken as the default. */
     IndexMask	= 0x00FF	/* If bits 30 and 31 are set, then these sixteen bits
 				 * indicate the index of the setting in the setting name
 				 * array for this feature which should be taken
 				 * as the default. */
   };

   unsigned int get_selector_infos (unsigned int                           start_offset,
 				   unsigned int                          *selectors_count, /* IN/OUT.  May be NULL. */
 				   hb_aat_layout_feature_selector_info_t *selectors,       /* OUT.     May be NULL. */
 				   unsigned int                          *pdefault_index,  /* OUT.     May be NULL. */
 				   const void *base) const
   {
     hb_array_t< const SettingName> settings_table = (base+settingTableZ).as_array (nSettings);

     static_assert (Index::NOT_FOUND_INDEX == HB_AAT_LAYOUT_NO_SELECTOR_INDEX, "");

     hb_aat_layout_feature_selector_t default_selector = HB_AAT_LAYOUT_FEATURE_SELECTOR_INVALID;
     unsigned int default_index = Index::NOT_FOUND_INDEX;
     if (featureFlags & Exclusive)
     {
       default_index = (featureFlags & NotDefault) ? featureFlags & IndexMask : 0;
       default_selector = settings_table[default_index].get_selector ();
     }
     if (pdefault_index)
       *pdefault_index = default_index;

     if (selectors_count)
     {
       + settings_table.sub_array (start_offset, selectors_count)
       | hb_map ([=] (const SettingName& setting) { return setting.get_info (default_selector); })
       | hb_sink (hb_array (selectors, *selectors_count))
       ;
     }
     return settings_table.length;
   }

   hb_aat_layout_feature_type_t get_feature_type () const
   { return (hb_aat_layout_feature_type_t) (unsigned int) feature; }

   hb_ot_name_id_t get_feature_name_id () const { return nameIndex; }

   bool is_exclusive () const { return featureFlags & Exclusive; }

   /* A FeatureName with no settings is meaningless */
   bool has_data () const { return nSettings; }

   bool sanitize (hb_sanitize_context_t *c, const void *base) const
   {
     TRACE_SANITIZE (this);
     return_trace (likely (c->check_struct (this) &&
 			  (base+settingTableZ).sanitize (c, nSettings)));
   }

   protected:
   HBUINT16	feature;	/* Feature type. */
   HBUINT16	nSettings;	/* The number of records in the setting name array. */
   LNNOffsetTo<UnsizedArrayOf<SettingName>>
 		settingTableZ;	/* Offset in bytes from the beginning of this table to
 				 * this feature's setting name array. The actual type of
 				 * record this offset refers to will depend on the
 				 * exclusivity value, as described below. */
   HBUINT16	featureFlags;	/* Single-bit flags associated with the feature type. */
   HBINT16	nameIndex;	/* The name table index for the feature's name.
 				 * This index has values greater than 255 and
 				 * less than 32768. */
   public:
   DEFINE_SIZE_STATIC (12);
 };

 struct feat
 {
   static constexpr hb_tag_t tableTag = HB_AAT_TAG_feat;

   bool has_data () const { return version.to_int (); }

   unsigned int get_feature_types (unsigned int                  start_offset,
 				  unsigned int                 *count,
 				  hb_aat_layout_feature_type_t *features) const
   {
     if (count)
     {
       + namesZ.as_array (featureNameCount).sub_array (start_offset, count)
       | hb_map (&FeatureName::get_feature_type)
       | hb_sink (hb_array (features, *count))
       ;
     }
     return featureNameCount;
   }

   bool exposes_feature (hb_aat_layout_feature_type_t feature_type) const
   { return get_feature (feature_type).has_data (); }

   const FeatureName& get_feature (hb_aat_layout_feature_type_t feature_type) const
   { return namesZ.bsearch (featureNameCount, feature_type); }

   hb_ot_name_id_t get_feature_name_id (hb_aat_layout_feature_type_t feature) const
   { return get_feature (feature).get_feature_name_id (); }

   unsigned int get_selector_infos (hb_aat_layout_feature_type_t           feature_type,
 				   unsigned int                           start_offset,
 				   unsigned int                          *selectors_count, /* IN/OUT.  May be NULL. */
 				   hb_aat_layout_feature_selector_info_t *selectors,       /* OUT.     May be NULL. */
 				   unsigned int                          *default_index    /* OUT.     May be NULL. */) const
   {
     return get_feature (feature_type).get_selector_infos (start_offset, selectors_count, selectors,
 							  default_index, this);
   }

   bool sanitize (hb_sanitize_context_t *c) const
   {
     TRACE_SANITIZE (this);
     return_trace (likely (c->check_struct (this) &&
 			  version.major == 1 &&
 			  namesZ.sanitize (c, featureNameCount, this)));
   }

   protected:
   FixedVersion<>version;	/* Version number of the feature name table
 				 * (0x00010000 for the current version). */
   HBUINT16	featureNameCount;
 				/* The number of entries in the feature name array. */
   HBUINT16	reserved1;	/* Reserved (set to zero). */
   HBUINT32	reserved2;	/* Reserved (set to zero). */
   SortedUnsizedArrayOf<FeatureName>
 		namesZ;		/* The feature name array. */
   public:
   DEFINE_SIZE_ARRAY (12, namesZ);
 };

 } /* namespace AAT */

 #endif /* HB_AAT_LAYOUT_FEAT_TABLE_HH */
	/*
	* Copyright © 2018 Ebrahim Byagowi
	*
	* 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.
	*/

	#ifndef HB_AAT_LAYOUT_FEAT_TABLE_HH
	#define HB_AAT_LAYOUT_FEAT_TABLE_HH

	#include "hb-aat-layout-common.hh"

	/*
	* feat -- Feature Name
	* https://developer.apple.com/fonts/TrueType-Reference-Manual/RM06/Chap6feat.html
	*/
	#define HB_AAT_TAG_feat HB_TAG('f','e','a','t')


	namespace AAT {


	struct SettingName
	{
	friend struct FeatureName;

	int cmp (hb_aat_layout_feature_selector_t key) const
	{ return (int) key - (int) setting; }

	hb_aat_layout_feature_selector_t get_selector () const
	{ return (hb_aat_layout_feature_selector_t) (unsigned) setting; }

	hb_aat_layout_feature_selector_info_t get_info (hb_aat_layout_feature_selector_t default_selector) const
	{
	return {
	nameIndex,
	(hb_aat_layout_feature_selector_t) (unsigned int) setting,
	default_selector == HB_AAT_LAYOUT_FEATURE_SELECTOR_INVALID
	? (hb_aat_layout_feature_selector_t) (setting + 1)
	: default_selector,
	0
	};
	}

	bool sanitize (hb_sanitize_context_t *c) const
	{
	TRACE_SANITIZE (this);
	return_trace (likely (c->check_struct (this)));
	}

	protected:
	HBUINT16 setting; /* The setting. */
	NameID nameIndex; /* The name table index for the setting's name. */
	public:
	DEFINE_SIZE_STATIC (4);
	};
	DECLARE_NULL_NAMESPACE_BYTES (AAT, SettingName);

	struct feat;

	struct FeatureName
	{
	int cmp (hb_aat_layout_feature_type_t key) const
	{ return (int) key - (int) feature; }

	enum {
	Exclusive = 0x8000, /* If set, the feature settings are mutually exclusive. */
	NotDefault = 0x4000, /* If clear, then the setting with an index of 0 in
	* the setting name array for this feature should
	* be taken as the default for the feature
	* (if one is required). If set, then bits 0-15 of this
	* featureFlags field contain the index of the setting
	* which is to be taken as the default. */
	IndexMask = 0x00FF /* If bits 30 and 31 are set, then these sixteen bits
	* indicate the index of the setting in the setting name
	* array for this feature which should be taken
	* as the default. */
	};

	unsigned int get_selector_infos (unsigned int start_offset,
	unsigned int selectors_count, / IN/OUT. May be NULL. */
	hb_aat_layout_feature_selector_info_t selectors, / OUT. May be NULL. */
	unsigned int pdefault_index, / OUT. May be NULL. */
	const void *base) const
	{
	hb_array_t< const SettingName> settings_table = (base+settingTableZ).as_array (nSettings);

	static_assert (Index::NOT_FOUND_INDEX == HB_AAT_LAYOUT_NO_SELECTOR_INDEX, "");

	hb_aat_layout_feature_selector_t default_selector = HB_AAT_LAYOUT_FEATURE_SELECTOR_INVALID;
	unsigned int default_index = Index::NOT_FOUND_INDEX;
	if (featureFlags & Exclusive)
	{
	default_index = (featureFlags & NotDefault) ? featureFlags & IndexMask : 0;
	default_selector = settings_table[default_index].get_selector ();
	}
	if (pdefault_index)
	*pdefault_index = default_index;

	if (selectors_count)
	{
	+ settings_table.sub_array (start_offset, selectors_count)
	\| hb_map ([=] (const SettingName& setting) { return setting.get_info (default_selector); })
	\| hb_sink (hb_array (selectors, *selectors_count))
	;
	}
	return settings_table.length;
	}

	hb_aat_layout_feature_type_t get_feature_type () const
	{ return (hb_aat_layout_feature_type_t) (unsigned int) feature; }

	hb_ot_name_id_t get_feature_name_id () const { return nameIndex; }

	bool is_exclusive () const { return featureFlags & Exclusive; }

	/* A FeatureName with no settings is meaningless */
	bool has_data () const { return nSettings; }

	bool sanitize (hb_sanitize_context_t c, const void base) const
	{
	TRACE_SANITIZE (this);
	return_trace (likely (c->check_struct (this) &&
	(base+settingTableZ).sanitize (c, nSettings)));
	}

	protected:
	HBUINT16 feature; /* Feature type. */
	HBUINT16 nSettings; /* The number of records in the setting name array. */
	LNNOffsetTo<UnsizedArrayOf<SettingName>>
	settingTableZ; /* Offset in bytes from the beginning of this table to
	* this feature's setting name array. The actual type of
	* record this offset refers to will depend on the
	* exclusivity value, as described below. */
	HBUINT16 featureFlags; /* Single-bit flags associated with the feature type. */
	HBINT16 nameIndex; /* The name table index for the feature's name.
	* This index has values greater than 255 and
	* less than 32768. */
	public:
	DEFINE_SIZE_STATIC (12);
	};

	struct feat
	{
	static constexpr hb_tag_t tableTag = HB_AAT_TAG_feat;

	bool has_data () const { return version.to_int (); }

	unsigned int get_feature_types (unsigned int start_offset,
	unsigned int *count,
	hb_aat_layout_feature_type_t *features) const
	{
	if (count)
	{
	+ namesZ.as_array (featureNameCount).sub_array (start_offset, count)
	\| hb_map (&FeatureName::get_feature_type)
	\| hb_sink (hb_array (features, *count))
	;
	}
	return featureNameCount;
	}

	bool exposes_feature (hb_aat_layout_feature_type_t feature_type) const
	{ return get_feature (feature_type).has_data (); }

	const FeatureName& get_feature (hb_aat_layout_feature_type_t feature_type) const
	{ return namesZ.bsearch (featureNameCount, feature_type); }

	hb_ot_name_id_t get_feature_name_id (hb_aat_layout_feature_type_t feature) const
	{ return get_feature (feature).get_feature_name_id (); }

	unsigned int get_selector_infos (hb_aat_layout_feature_type_t feature_type,
	unsigned int start_offset,
	unsigned int selectors_count, / IN/OUT. May be NULL. */
	hb_aat_layout_feature_selector_info_t selectors, / OUT. May be NULL. */
	unsigned int default_index / OUT. May be NULL. */) const
	{
	return get_feature (feature_type).get_selector_infos (start_offset, selectors_count, selectors,
	default_index, this);
	}

	bool sanitize (hb_sanitize_context_t *c) const
	{
	TRACE_SANITIZE (this);
	return_trace (likely (c->check_struct (this) &&
	version.major == 1 &&
	namesZ.sanitize (c, featureNameCount, this)));
	}

	protected:
	FixedVersion<>version; /* Version number of the feature name table
	* (0x00010000 for the current version). */
	HBUINT16 featureNameCount;
	/* The number of entries in the feature name array. */
	HBUINT16 reserved1; /* Reserved (set to zero). */
	HBUINT32 reserved2; /* Reserved (set to zero). */
	SortedUnsizedArrayOf<FeatureName>
	namesZ; /* The feature name array. */
	public:
	DEFINE_SIZE_ARRAY (12, namesZ);
	};

	} /* namespace AAT */

	#endif /* HB_AAT_LAYOUT_FEAT_TABLE_HH */