chromium/third_party/harfbuzz-ng/src/src/hb-ot-shaper-indic.cc

/*
 * Copyright © 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.
 *
 * Google Author(s): Behdad Esfahbod
 */

#include "hb.hh"

#ifndef HB_NO_OT_SHAPE

#include "hb-ot-shaper-indic.hh"
#include "hb-ot-shaper-indic-machine.hh"
#include "hb-ot-shaper-vowel-constraints.hh"
#include "hb-ot-layout.hh"


/*
 * Indic shaper.
 */


static inline void
set_indic_properties (hb_glyph_info_t &info)
{ … }


static inline bool
is_one_of (const hb_glyph_info_t &info, unsigned int flags)
{ … }

/* Note:
 *
 * We treat Vowels and placeholders as if they were consonants.  This is safe because Vowels
 * cannot happen in a consonant syllable.  The plus side however is, we can call the
 * consonant syllable logic from the vowel syllable function and get it all right!
 *
 * Keep in sync with consonant_categories in the generator. */
#define CONSONANT_FLAGS_INDIC …

static inline bool
is_consonant (const hb_glyph_info_t &info)
{ … }

#define JOINER_FLAGS …

static inline bool
is_joiner (const hb_glyph_info_t &info)
{ … }

static inline bool
is_halant (const hb_glyph_info_t &info)
{ … }

struct hb_indic_would_substitute_feature_t
{ … };


/*
 * Indic configurations.  Note that we do not want to keep every single script-specific
 * behavior in these tables necessarily.  This should mainly be used for per-script
 * properties that are cheaper keeping here, than in the code.  Ie. if, say, one and
 * only one script has an exception, that one script can be if'ed directly in the code,
 * instead of adding a new flag in these structs.
 */

enum reph_position_t { … };
enum reph_mode_t { … };
enum blwf_mode_t { … };
struct indic_config_t
{ … };

static const indic_config_t indic_configs[] = …;


static const hb_ot_map_feature_t
indic_features[] = …;

/*
 * Must be in the same order as the indic_features array.
 */
enum { … };

static bool
setup_syllables_indic (const hb_ot_shape_plan_t *plan,
		       hb_font_t *font,
		       hb_buffer_t *buffer);
static bool
initial_reordering_indic (const hb_ot_shape_plan_t *plan,
			  hb_font_t *font,
			  hb_buffer_t *buffer);
static bool
final_reordering_indic (const hb_ot_shape_plan_t *plan,
			hb_font_t *font,
			hb_buffer_t *buffer);

static void
collect_features_indic (hb_ot_shape_planner_t *plan)
{ … }

static void
override_features_indic (hb_ot_shape_planner_t *plan)
{ … }


struct indic_shape_plan_t
{ … };

static void *
data_create_indic (const hb_ot_shape_plan_t *plan)
{ … }

static void
data_destroy_indic (void *data)
{ … }

static indic_position_t
consonant_position_from_face (const indic_shape_plan_t *indic_plan,
			      const hb_codepoint_t consonant,
			      const hb_codepoint_t virama,
			      hb_face_t *face)
{ … }

static void
setup_masks_indic (const hb_ot_shape_plan_t *plan HB_UNUSED,
		   hb_buffer_t              *buffer,
		   hb_font_t                *font HB_UNUSED)
{ … }

static bool
setup_syllables_indic (const hb_ot_shape_plan_t *plan HB_UNUSED,
		       hb_font_t *font HB_UNUSED,
		       hb_buffer_t *buffer)
{ … }

static int
compare_indic_order (const hb_glyph_info_t *pa, const hb_glyph_info_t *pb)
{ … }



static void
update_consonant_positions_indic (const hb_ot_shape_plan_t *plan,
				  hb_font_t         *font,
				  hb_buffer_t       *buffer)
{ … }


/* Rules from:
 * https://docs.microsqoft.com/en-us/typography/script-development/devanagari */

static void
initial_reordering_consonant_syllable (const hb_ot_shape_plan_t *plan,
				       hb_face_t *face,
				       hb_buffer_t *buffer,
				       unsigned int start, unsigned int end)
{ … }

static void
initial_reordering_standalone_cluster (const hb_ot_shape_plan_t *plan,
				       hb_face_t *face,
				       hb_buffer_t *buffer,
				       unsigned int start, unsigned int end)
{ … }

static void
initial_reordering_syllable_indic (const hb_ot_shape_plan_t *plan,
				   hb_face_t *face,
				   hb_buffer_t *buffer,
				   unsigned int start, unsigned int end)
{ … }

static bool
initial_reordering_indic (const hb_ot_shape_plan_t *plan,
			  hb_font_t *font,
			  hb_buffer_t *buffer)
{ … }

static void
final_reordering_syllable_indic (const hb_ot_shape_plan_t *plan,
				 hb_buffer_t *buffer,
				 unsigned int start, unsigned int end)
{ … }


static bool
final_reordering_indic (const hb_ot_shape_plan_t *plan,
			hb_font_t *font HB_UNUSED,
			hb_buffer_t *buffer)
{ … }


static void
preprocess_text_indic (const hb_ot_shape_plan_t *plan,
		       hb_buffer_t              *buffer,
		       hb_font_t                *font)
{ … }

static bool
decompose_indic (const hb_ot_shape_normalize_context_t *c,
		 hb_codepoint_t  ab,
		 hb_codepoint_t *a,
		 hb_codepoint_t *b)
{ … }

static bool
compose_indic (const hb_ot_shape_normalize_context_t *c,
	       hb_codepoint_t  a,
	       hb_codepoint_t  b,
	       hb_codepoint_t *ab)
{ … }


const hb_ot_shaper_t _hb_ot_shaper_indic = …;


#endif