harfbuzz/src/hb-ot-shape.c

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/*
* Copyright (C) 2009 Red Hat, Inc.
*
* This is part of HarfBuzz, an OpenType Layout engine 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
*/
#include "hb-ot-shape-private.h"
#include "hb-buffer-private.h"
#include "hb-ot-layout.h"
hb_tag_t default_features[] = {
/* GSUB */
HB_TAG('c','c','m','p'),
HB_TAG('l','o','c','l'),
HB_TAG('l','i','g','a'),
HB_TAG('c','l','i','g'),
/* GPOS */
HB_TAG('k','e','r','n'),
HB_TAG('m','a','r','k'),
HB_TAG('m','k','m','k'),
};
static void
add_feature (hb_face_t *face,
hb_tag_t table_tag,
unsigned int feature_index,
unsigned int *lookups,
unsigned int *num_lookups,
unsigned int room_lookups)
{
unsigned int i = room_lookups - *num_lookups;
hb_ot_layout_feature_get_lookup_indexes (face, table_tag, feature_index, 0,
&i,
lookups + *num_lookups);
*num_lookups += i;
}
static int
cmp_lookups (const void *p1, const void *p2)
{
unsigned int a = * (const unsigned int *) p1;
unsigned int b = * (const unsigned int *) p2;
return a - b;
}
static void
setup_lookups (hb_font_t *font,
hb_face_t *face,
hb_buffer_t *buffer,
hb_feature_t *features,
unsigned int num_features,
hb_tag_t table_tag,
unsigned int *lookups,
unsigned int *num_lookups)
{
unsigned int i, j, script_index, language_index, feature_index, room_lookups;
room_lookups = *num_lookups;
*num_lookups = 0;
hb_ot_layout_table_choose_script (face, table_tag,
hb_ot_tags_from_script (buffer->script),
&script_index);
hb_ot_layout_script_find_language (face, table_tag, script_index,
hb_ot_tag_from_language (buffer->language),
&language_index);
if (hb_ot_layout_language_get_required_feature_index (face, table_tag, script_index, language_index,
&feature_index))
add_feature (face, table_tag, feature_index, lookups, num_lookups, room_lookups);
for (i = 0; i < ARRAY_LENGTH (default_features); i++)
{
if (hb_ot_layout_language_find_feature (face, table_tag, script_index, language_index,
default_features[i],
&feature_index))
add_feature (face, table_tag, feature_index, lookups, num_lookups, room_lookups);
}
qsort (lookups, *num_lookups, sizeof (lookups[0]), cmp_lookups);
if (*num_lookups)
{
for (i = 1, j = 0; i < *num_lookups; i++)
if (lookups[i] != lookups[j])
lookups[++j] = lookups[i];
lookups[j++] = lookups[i - 1];
*num_lookups = j;
}
}
gboolean
_hb_ot_substitute_complex (hb_font_t *font,
hb_face_t *face,
hb_buffer_t *buffer,
hb_feature_t *features,
unsigned int num_features)
{
unsigned int lookups[1000];
unsigned int num_lookups = ARRAY_LENGTH (lookups);
unsigned int i;
if (!hb_ot_layout_has_substitution (face))
return FALSE;
setup_lookups (font, face, buffer, features, num_features,
HB_OT_TAG_GSUB,
lookups, &num_lookups);
for (i = 0; i < num_lookups; i++)
hb_ot_layout_substitute_lookup (face, buffer, lookups[i], 0xFFFF);
return TRUE;
}
gboolean
_hb_ot_position_complex (hb_font_t *font,
hb_face_t *face,
hb_buffer_t *buffer,
hb_feature_t *features,
unsigned int num_features)
{
unsigned int lookups[1000];
unsigned int num_lookups = ARRAY_LENGTH (lookups);
unsigned int i;
if (!hb_ot_layout_has_positioning (face))
return FALSE;
setup_lookups (font, face, buffer, features, num_features,
HB_OT_TAG_GPOS,
lookups, &num_lookups);
for (i = 0; i < num_lookups; i++)
hb_ot_layout_position_lookup (font, face, buffer, lookups[i], 0xFFFF);
hb_ot_layout_position_finish (font, face, buffer);
return TRUE;
}