/*
* 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; }
void get_info (hb_aat_layout_feature_selector_info_t *s,
hb_aat_layout_feature_selector_t default_selector) const
{
s->name_id = nameIndex;
s->enable = (hb_aat_layout_feature_selector_t) (unsigned int) setting;
s->disable = default_selector == HB_AAT_LAYOUT_FEATURE_SELECTOR_INVALID ?
(hb_aat_layout_feature_selector_t) (s->enable + 1) :
default_selector;
s->reserved = 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)
{
hb_array_t<const SettingName> arr = settings_table.sub_array (start_offset, selectors_count);
unsigned int count = arr.len;
for (unsigned int i = 0; i < count; i++)
settings_table[start_offset + i].get_info (&selectors[i], default_selector);
}
return settings_table.len;
}
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 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. */
LOffsetTo<UnsizedArrayOf<SettingName>, false>
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
{
enum { 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
{
unsigned int feature_count = featureNameCount;
if (count && *count)
{
unsigned int len = MIN (feature_count - start_offset, *count);
for (unsigned int i = 0; i < len; i++)
features[i] = namesZ[i + start_offset].get_feature_type ();
*count = len;
}
return featureNameCount;
}
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_STATIC (24);
};
} /* namespace AAT */
#endif /* HB_AAT_LAYOUT_FEAT_TABLE_HH */