/*
* Copyright © 2011,2012,2013 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-ot-shape-complex-indic-private.hh"
/* buffer var allocations */
#define sea_category() complex_var_u8_0() /* indic_category_t */
#define sea_position() complex_var_u8_1() /* indic_position_t */
/*
* South-East Asian shaper.
* Loosely based on the Myanmar spec / shaper.
* There is no OpenType spec for this.
*/
static const hb_tag_t
basic_features[] =
{
/*
* Basic features.
* These features are applied in order, one at a time, after initial_reordering.
*/
HB_TAG('p','r','e','f'),
HB_TAG('a','b','v','f'),
HB_TAG('b','l','w','f'),
HB_TAG('p','s','t','f'),
};
static const hb_tag_t
other_features[] =
{
/*
* Other features.
* These features are applied all at once, after final_reordering.
*/
HB_TAG('p','r','e','s'),
HB_TAG('a','b','v','s'),
HB_TAG('b','l','w','s'),
HB_TAG('p','s','t','s'),
/* Positioning features, though we don't care about the types. */
HB_TAG('d','i','s','t'),
};
static void
setup_syllables (const hb_ot_shape_plan_t *plan,
hb_font_t *font,
hb_buffer_t *buffer);
static void
initial_reordering (const hb_ot_shape_plan_t *plan,
hb_font_t *font,
hb_buffer_t *buffer);
static void
final_reordering (const hb_ot_shape_plan_t *plan,
hb_font_t *font,
hb_buffer_t *buffer);
static void
collect_features_sea (hb_ot_shape_planner_t *plan)
{
hb_ot_map_builder_t *map = &plan->map;
/* Do this before any lookups have been applied. */
map->add_gsub_pause (setup_syllables);
map->add_global_bool_feature (HB_TAG('l','o','c','l'));
/* The Indic specs do not require ccmp, but we apply it here since if
* there is a use of it, it's typically at the beginning. */
map->add_global_bool_feature (HB_TAG('c','c','m','p'));
map->add_gsub_pause (initial_reordering);
for (unsigned int i = 0; i < ARRAY_LENGTH (basic_features); i++)
{
map->add_feature (basic_features[i], 1, F_GLOBAL | F_MANUAL_ZWJ);
map->add_gsub_pause (NULL);
}
map->add_gsub_pause (final_reordering);
for (unsigned int i = 0; i < ARRAY_LENGTH (other_features); i++)
map->add_feature (other_features[i], 1, F_GLOBAL | F_MANUAL_ZWJ);
}
static void
override_features_sea (hb_ot_shape_planner_t *plan)
{
plan->map.add_feature (HB_TAG('l','i','g','a'), 0, F_GLOBAL);
}
enum syllable_type_t {
consonant_syllable,
broken_cluster,
non_sea_cluster,
};
#include "hb-ot-shape-complex-sea-machine.hh"
/* Note: This enum is duplicated in the -machine.rl source file.
* Not sure how to avoid duplication. */
enum sea_category_t {
// OT_C = 1,
OT_GB = 12, /* Generic Base XXX DOTTED CIRCLE only for now */
// OT_H = 4, /* Halant */
OT_IV = 2, /* Independent Vowel */
OT_MR = 22, /* Medial Ra */
// OT_CM = 17, /* Consonant Medial */
OT_VAbv = 26,
OT_VBlw = 27,
OT_VPre = 28,
OT_VPst = 29,
OT_T = 3, /* Tone Marks */
// OT_A = 10, /* Anusvara */
};
static inline void
set_sea_properties (hb_glyph_info_t &info)
{
hb_codepoint_t u = info.codepoint;
unsigned int type = hb_indic_get_categories (u);
indic_category_t cat = (indic_category_t) (type & 0x7Fu);
indic_position_t pos = (indic_position_t) (type >> 8);
/* Medial Ra */
if (u == 0x1A55u || u == 0xAA34u)
cat = (indic_category_t) OT_MR;
if (cat == OT_M)
{
switch ((int) pos)
{
case POS_PRE_C: cat = (indic_category_t) OT_VPre; break;
case POS_ABOVE_C: cat = (indic_category_t) OT_VAbv; break;
case POS_BELOW_C: cat = (indic_category_t) OT_VBlw; break;
case POS_POST_C: cat = (indic_category_t) OT_VPst; break;
}
}
info.sea_category() = (sea_category_t) cat;
info.sea_position() = pos;
}
static void
setup_masks_sea (const hb_ot_shape_plan_t *plan HB_UNUSED,
hb_buffer_t *buffer,
hb_font_t *font HB_UNUSED)
{
HB_BUFFER_ALLOCATE_VAR (buffer, sea_category);
HB_BUFFER_ALLOCATE_VAR (buffer, sea_position);
/* We cannot setup masks here. We save information about characters
* and setup masks later on in a pause-callback. */
unsigned int count = buffer->len;
hb_glyph_info_t *info = buffer->info;
for (unsigned int i = 0; i < count; i++)
set_sea_properties (info[i]);
}
static void
setup_syllables (const hb_ot_shape_plan_t *plan HB_UNUSED,
hb_font_t *font HB_UNUSED,
hb_buffer_t *buffer)
{
find_syllables (buffer);
}
static int
compare_sea_order (const hb_glyph_info_t *pa, const hb_glyph_info_t *pb)
{
int a = pa->sea_position();
int b = pb->sea_position();
return a < b ? -1 : a == b ? 0 : +1;
}
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)
{
hb_glyph_info_t *info = buffer->info;
unsigned int base = start;
/* Reorder! */
unsigned int i = start;
for (; i < base; i++)
info[i].sea_position() = POS_PRE_C;
if (i < end)
{
info[i].sea_position() = POS_BASE_C;
i++;
}
for (; i < end; i++)
{
if (info[i].sea_category() == OT_MR) /* Pre-base reordering */
{
info[i].sea_position() = POS_PRE_C;
continue;
}
if (info[i].sea_category() == OT_VPre) /* Left matra */
{
info[i].sea_position() = POS_PRE_M;
continue;
}
info[i].sea_position() = POS_AFTER_MAIN;
}
buffer->merge_clusters (start, end);
/* Sit tight, rock 'n roll! */
hb_bubble_sort (info + start, end - start, compare_sea_order);
}
static void
initial_reordering_broken_cluster (const hb_ot_shape_plan_t *plan,
hb_face_t *face,
hb_buffer_t *buffer,
unsigned int start, unsigned int end)
{
/* We already inserted dotted-circles, so just call the consonant_syllable. */
initial_reordering_consonant_syllable (plan, face, buffer, start, end);
}
static void
initial_reordering_non_sea_cluster (const hb_ot_shape_plan_t *plan HB_UNUSED,
hb_face_t *face HB_UNUSED,
hb_buffer_t *buffer HB_UNUSED,
unsigned int start HB_UNUSED, unsigned int end HB_UNUSED)
{
/* Nothing to do right now. If we ever switch to using the output
* buffer in the reordering process, we'd need to next_glyph() here. */
}
static void
initial_reordering_syllable (const hb_ot_shape_plan_t *plan,
hb_face_t *face,
hb_buffer_t *buffer,
unsigned int start, unsigned int end)
{
syllable_type_t syllable_type = (syllable_type_t) (buffer->info[start].syllable() & 0x0F);
switch (syllable_type) {
case consonant_syllable: initial_reordering_consonant_syllable (plan, face, buffer, start, end); return;
case broken_cluster: initial_reordering_broken_cluster (plan, face, buffer, start, end); return;
case non_sea_cluster: initial_reordering_non_sea_cluster (plan, face, buffer, start, end); return;
}
}
static inline void
insert_dotted_circles (const hb_ot_shape_plan_t *plan HB_UNUSED,
hb_font_t *font,
hb_buffer_t *buffer)
{
/* Note: This loop is extra overhead, but should not be measurable. */
bool has_broken_syllables = false;
unsigned int count = buffer->len;
hb_glyph_info_t *info = buffer->info;
for (unsigned int i = 0; i < count; i++)
if ((info[i].syllable() & 0x0F) == broken_cluster)
{
has_broken_syllables = true;
break;
}
if (likely (!has_broken_syllables))
return;
hb_codepoint_t dottedcircle_glyph;
if (!font->get_glyph (0x25CCu, 0, &dottedcircle_glyph))
return;
hb_glyph_info_t dottedcircle = {0};
dottedcircle.codepoint = 0x25CCu;
set_sea_properties (dottedcircle);
dottedcircle.codepoint = dottedcircle_glyph;
buffer->clear_output ();
buffer->idx = 0;
unsigned int last_syllable = 0;
while (buffer->idx < buffer->len)
{
unsigned int syllable = buffer->cur().syllable();
syllable_type_t syllable_type = (syllable_type_t) (syllable & 0x0F);
if (unlikely (last_syllable != syllable && syllable_type == broken_cluster))
{
last_syllable = syllable;
hb_glyph_info_t info = dottedcircle;
info.cluster = buffer->cur().cluster;
info.mask = buffer->cur().mask;
info.syllable() = buffer->cur().syllable();
buffer->output_info (info);
}
else
buffer->next_glyph ();
}
buffer->swap_buffers ();
}
static void
initial_reordering (const hb_ot_shape_plan_t *plan,
hb_font_t *font,
hb_buffer_t *buffer)
{
insert_dotted_circles (plan, font, buffer);
hb_glyph_info_t *info = buffer->info;
unsigned int count = buffer->len;
if (unlikely (!count)) return;
unsigned int last = 0;
unsigned int last_syllable = info[0].syllable();
for (unsigned int i = 1; i < count; i++)
if (last_syllable != info[i].syllable()) {
initial_reordering_syllable (plan, font->face, buffer, last, i);
last = i;
last_syllable = info[last].syllable();
}
initial_reordering_syllable (plan, font->face, buffer, last, count);
}
static void
final_reordering (const hb_ot_shape_plan_t *plan,
hb_font_t *font HB_UNUSED,
hb_buffer_t *buffer)
{
hb_glyph_info_t *info = buffer->info;
unsigned int count = buffer->len;
/* Zero syllables now... */
for (unsigned int i = 0; i < count; i++)
info[i].syllable() = 0;
HB_BUFFER_DEALLOCATE_VAR (buffer, sea_category);
HB_BUFFER_DEALLOCATE_VAR (buffer, sea_position);
}
const hb_ot_complex_shaper_t _hb_ot_complex_shaper_sea =
{
"sea",
collect_features_sea,
override_features_sea,
NULL, /* data_create */
NULL, /* data_destroy */
NULL, /* preprocess_text */
HB_OT_SHAPE_NORMALIZATION_MODE_COMPOSED_DIACRITICS_NO_SHORT_CIRCUIT,
NULL, /* decompose */
NULL, /* compose */
setup_masks_sea,
HB_OT_SHAPE_ZERO_WIDTH_MARKS_NONE,
false, /* fallback_position */
};