harfbuzz/src/hb-ot-map-private.hh

206 lines
6.8 KiB
C++

/*
* Copyright © 2009,2010 Red Hat, Inc.
* Copyright © 2010,2011,2012 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
*/
#ifndef HB_OT_MAP_PRIVATE_HH
#define HB_OT_MAP_PRIVATE_HH
#include "hb-buffer-private.hh"
#include "hb-ot-layout-private.hh"
static const hb_tag_t table_tags[2] = {HB_OT_TAG_GSUB, HB_OT_TAG_GPOS};
struct hb_ot_map_t
{
friend struct hb_ot_map_builder_t;
public:
struct feature_map_t {
hb_tag_t tag; /* should be first for our bsearch to work */
unsigned int index[2]; /* GSUB/GPOS */
unsigned int stage[2]; /* GSUB/GPOS */
unsigned int shift;
hb_mask_t mask;
hb_mask_t _1_mask; /* mask for value=1, for quick access */
hb_bool_t needs_fallback;
static int cmp (const feature_map_t *a, const feature_map_t *b)
{ return a->tag < b->tag ? -1 : a->tag > b->tag ? 1 : 0; }
};
struct lookup_map_t {
unsigned int index;
hb_mask_t mask;
static int cmp (const lookup_map_t *a, const lookup_map_t *b)
{ return a->index < b->index ? -1 : a->index > b->index ? 1 : 0; }
};
typedef void (*pause_func_t) (const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer);
struct pause_map_t {
unsigned int num_lookups; /* Cumulative */
pause_func_t callback;
};
hb_ot_map_t (void) { memset (this, 0, sizeof (*this)); }
inline hb_mask_t get_global_mask (void) const { return global_mask; }
inline hb_mask_t get_mask (hb_tag_t feature_tag, unsigned int *shift = NULL) const {
const feature_map_t *map = features.bsearch (&feature_tag);
if (shift) *shift = map ? map->shift : 0;
return map ? map->mask : 0;
}
inline bool needs_fallback (hb_tag_t feature_tag) const {
const feature_map_t *map = features.bsearch (&feature_tag);
return map ? map->needs_fallback : false;
}
inline hb_mask_t get_1_mask (hb_tag_t feature_tag) const {
const feature_map_t *map = features.bsearch (&feature_tag);
return map ? map->_1_mask : 0;
}
inline unsigned int get_feature_index (unsigned int table_index, hb_tag_t feature_tag) const {
const feature_map_t *map = features.bsearch (&feature_tag);
return map ? map->index[table_index] : HB_OT_LAYOUT_NO_FEATURE_INDEX;
}
inline unsigned int get_feature_stage (unsigned int table_index, hb_tag_t feature_tag) const {
const feature_map_t *map = features.bsearch (&feature_tag);
return map ? map->stage[table_index] : (unsigned int) -1;
}
inline void get_stage_lookups (unsigned int table_index, unsigned int stage,
const struct lookup_map_t **plookups, unsigned int *lookup_count) const {
if (unlikely (stage == (unsigned int) -1)) {
*plookups = NULL;
*lookup_count = 0;
return;
}
assert (stage <= pauses[table_index].len);
unsigned int start = stage ? pauses[table_index][stage - 1].num_lookups : 0;
unsigned int end = stage < pauses[table_index].len ? pauses[table_index][stage].num_lookups : lookups[table_index].len;
*plookups = &lookups[table_index][start];
*lookup_count = end - start;
}
inline hb_tag_t get_chosen_script (unsigned int table_index) const
{ return chosen_script[table_index]; }
HB_INTERNAL void substitute_closure (const struct hb_ot_shape_plan_t *plan, hb_face_t *face, hb_set_t *glyphs) const;
HB_INTERNAL void substitute (const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const;
HB_INTERNAL void position (const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const;
inline void finish (void) {
features.finish ();
lookups[0].finish ();
lookups[1].finish ();
pauses[0].finish ();
pauses[1].finish ();
}
private:
HB_INTERNAL void add_lookups (hb_face_t *face,
unsigned int table_index,
unsigned int feature_index,
hb_mask_t mask);
hb_mask_t global_mask;
hb_tag_t chosen_script[2];
hb_prealloced_array_t<feature_map_t, 8> features;
hb_prealloced_array_t<lookup_map_t, 32> lookups[2]; /* GSUB/GPOS */
hb_prealloced_array_t<pause_map_t, 1> pauses[2]; /* GSUB/GPOS */
};
struct hb_ot_map_builder_t
{
public:
hb_ot_map_builder_t (void) { memset (this, 0, sizeof (*this)); }
HB_INTERNAL void add_feature (hb_tag_t tag, unsigned int value, bool global, bool has_fallback = false);
inline void add_bool_feature (hb_tag_t tag, bool global = true, bool has_fallback = false)
{ add_feature (tag, 1, global, has_fallback); }
inline void add_gsub_pause (hb_ot_map_t::pause_func_t pause_func)
{ add_pause (0, pause_func); }
inline void add_gpos_pause (hb_ot_map_t::pause_func_t pause_func)
{ add_pause (1, pause_func); }
HB_INTERNAL void compile (hb_face_t *face,
const hb_segment_properties_t *props,
struct hb_ot_map_t &m);
inline void finish (void) {
feature_infos.finish ();
pauses[0].finish ();
pauses[1].finish ();
}
private:
struct feature_info_t {
hb_tag_t tag;
unsigned int seq; /* sequence#, used for stable sorting only */
unsigned int max_value;
bool global; /* whether the feature applies value to every glyph in the buffer */
bool has_fallback; /* whether to allocate bits even if feature not found */
unsigned int default_value; /* for non-global features, what should the unset glyphs take */
unsigned int stage[2]; /* GSUB/GPOS */
static int cmp (const feature_info_t *a, const feature_info_t *b)
{ return (a->tag != b->tag) ? (a->tag < b->tag ? -1 : 1) : (a->seq < b->seq ? -1 : 1); }
};
struct pause_info_t {
unsigned int stage;
hb_ot_map_t::pause_func_t callback;
};
HB_INTERNAL void add_pause (unsigned int table_index, hb_ot_map_t::pause_func_t pause_func);
unsigned int current_stage[2]; /* GSUB/GPOS */
hb_prealloced_array_t<feature_info_t,16> feature_infos;
hb_prealloced_array_t<pause_info_t, 1> pauses[2]; /* GSUB/GPOS */
};
#endif /* HB_OT_MAP_PRIVATE_HH */