{
/*
* Basic features.
- * These features are applied in order, one at a time, after initial_reordering.
+ * These features are applied in order, one at a time, after reordering.
*/
{HB_TAG('p','r','e','f'), F_NONE},
{HB_TAG('b','l','w','f'), F_NONE},
{HB_TAG('c','f','a','r'), F_NONE},
/*
* Other features.
- * These features are applied all at once, after final_reordering.
- * Default Bengali font in Windows for example has intermixed
- * lookups for init,pres,abvs,blws features.
+ * These features are applied all at once.
*/
{HB_TAG('p','r','e','s'), F_GLOBAL},
{HB_TAG('a','b','v','s'), F_GLOBAL},
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);
+reorder (const hb_ot_shape_plan_t *plan,
+ hb_font_t *font,
+ hb_buffer_t *buffer);
static void
clear_syllables (const hb_ot_shape_plan_t *plan,
hb_font_t *font,
unsigned int i = 0;
- map->add_gsub_pause (initial_reordering);
+ map->add_gsub_pause (reorder);
for (; i < KHMER_BASIC_FEATURES; i++) {
map->add_feature (khmer_features[i].tag, 1, khmer_features[i].flags | F_MANUAL_ZWJ | F_MANUAL_ZWNJ);
map->add_gsub_pause (nullptr);
}
- map->add_gsub_pause (final_reordering);
for (; i < KHMER_NUM_FEATURES; i++) {
map->add_feature (khmer_features[i].tag, 1, khmer_features[i].flags | F_MANUAL_ZWJ | F_MANUAL_ZWNJ);
}
buffer->unsafe_to_break (start, end);
}
-static int
-compare_khmer_order (const hb_glyph_info_t *pa, const hb_glyph_info_t *pb)
-{
- int a = pa->khmer_position();
- int b = pb->khmer_position();
-
- return a < b ? -1 : a == b ? 0 : +1;
-}
-
/* Rules from:
* https://docs.microsoft.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)
+reorder_consonant_syllable (const hb_ot_shape_plan_t *plan,
+ hb_face_t *face,
+ hb_buffer_t *buffer,
+ unsigned int start, unsigned int end)
{
const khmer_shape_plan_t *khmer_plan = (const khmer_shape_plan_t *) plan->data;
hb_glyph_info_t *info = buffer->info;
- /* 1. Khmer shaping assumes that a syllable will begin with a Cons, IndV, or Number. */
-
- /* The first consonant is always the base. */
- unsigned int base = start;
- info[base].khmer_position() = POS_BASE_C;
-
- /* Mark all subsequent consonants as below. */
- for (unsigned int i = base + 1; i < end; i++)
- if (is_consonant_or_vowel (info[i]))
- info[i].khmer_position() = POS_BELOW_C;
-
- /* Mark final consonants. A final consonant is one appearing after a matra,
- * like in Khmer. */
- for (unsigned int i = base + 1; i < end; i++)
- if (info[i].khmer_category() == OT_M) {
- for (unsigned int j = i + 1; j < end; j++)
- if (is_consonant_or_vowel (info[j])) {
- info[j].khmer_position() = POS_FINAL_C;
- break;
- }
- break;
- }
-
- /* Attach misc marks to previous char to move with them. */
- {
- khmer_position_t last_pos = POS_START;
- for (unsigned int i = start; i < end; i++)
- {
- if ((FLAG_UNSAFE (info[i].khmer_category()) & (JOINER_FLAGS | FLAG (OT_N) | FLAG (OT_RS) | MEDIAL_FLAGS | FLAG (OT_Coeng))))
- {
- info[i].khmer_position() = last_pos;
- if (unlikely (info[i].khmer_category() == OT_Coeng &&
- info[i].khmer_position() == POS_PRE_M))
- {
- /*
- * Uniscribe doesn't move the Halant with Left Matra.
- * TEST: U+092B,U+093F,U+094DE
- * We follow. This is important for the Sinhala
- * U+0DDA split matra since it decomposes to U+0DD9,U+0DCA
- * where U+0DD9 is a left matra and U+0DCA is the virama.
- * We don't want to move the virama with the left matra.
- * TEST: U+0D9A,U+0DDA
- */
- for (unsigned int j = i; j > start; j--)
- if (info[j - 1].khmer_position() != POS_PRE_M) {
- info[i].khmer_position() = info[j - 1].khmer_position();
- break;
- }
- }
- } else if (info[i].khmer_position() != POS_SMVD) {
- last_pos = (khmer_position_t) info[i].khmer_position();
- }
- }
- }
- /* For post-base consonants let them own anything before them
- * since the last consonant or matra. */
- {
- unsigned int last = base;
- for (unsigned int i = base + 1; i < end; i++)
- if (is_consonant_or_vowel (info[i]))
- {
- for (unsigned int j = last + 1; j < i; j++)
- if (info[j].khmer_position() < POS_SMVD)
- info[j].khmer_position() = info[i].khmer_position();
- last = i;
- } else if (info[i].khmer_category() == OT_M)
- last = i;
- }
-
- {
- /* Use syllable() for sort accounting temporarily. */
- unsigned int syllable = info[start].syllable();
- for (unsigned int i = start; i < end; i++)
- info[i].syllable() = i - start;
-
- /* Sit tight, rock 'n roll! */
- hb_stable_sort (info + start, end - start, compare_khmer_order);
- /* Find base again */
- base = end;
- for (unsigned int i = start; i < end; i++)
- if (info[i].khmer_position() == POS_BASE_C)
- {
- base = i;
- break;
- }
-
- if (unlikely (end - start >= 127))
- buffer->merge_clusters (start, end);
- else
- /* Note! syllable() is a one-byte field. */
- for (unsigned int i = base; i < end; i++)
- if (info[i].syllable() != 255)
- {
- unsigned int max = i;
- unsigned int j = start + info[i].syllable();
- while (j != i)
- {
- max = MAX (max, j);
- unsigned int next = start + info[j].syllable();
- info[j].syllable() = 255; /* So we don't process j later again. */
- j = next;
- }
- if (i != max)
- buffer->merge_clusters (i, max + 1);
- }
-
- /* Put syllable back in. */
- for (unsigned int i = start; i < end; i++)
- info[i].syllable() = syllable;
- }
-
- /* Setup masks now */
-
+ /* Setup masks. */
{
- hb_mask_t mask;
-
/* Post-base */
- mask = khmer_plan->mask_array[BLWF] | khmer_plan->mask_array[ABVF] | khmer_plan->mask_array[PSTF];
- for (unsigned int i = base + 1; i < end; i++)
+ hb_mask_t mask = khmer_plan->mask_array[BLWF] | khmer_plan->mask_array[ABVF] | khmer_plan->mask_array[PSTF];
+ for (unsigned int i = start + 1; i < end; i++)
info[i].mask |= mask;
}
- unsigned int pref_len = 2;
- if (khmer_plan->mask_array[PREF] && base + pref_len < end)
+ unsigned int num_coengs = 0;
+ for (unsigned int i = start + 1; i < end; i++)
{
- /* Find a Halant,Ra sequence and mark it for pre-base-reordering processing. */
- for (unsigned int i = base + 1; i + pref_len - 1 < end; i++) {
- hb_codepoint_t glyphs[2];
- for (unsigned int j = 0; j < pref_len; j++)
- glyphs[j] = info[i + j].codepoint;
- if (khmer_plan->pref.would_substitute (glyphs, pref_len, face))
+ /* """
+ * When a COENG + (Cons | IndV) combination are found (and subscript count
+ * is less than two) the character combination is handled according to the
+ * subscript type of the character following the COENG.
+ *
+ * ...
+ *
+ * Subscript Type 2 - The COENG + RO characters are reordered to immediately
+ * before the base glyph. Then the COENG + RO characters are assigned to have
+ * the 'pref' OpenType feature applied to them.
+ * """
+ */
+ if (info[i].khmer_category() == OT_Coeng && num_coengs <= 2 && i + 1 < end)
+ {
+ num_coengs++;
+
+ if (info[i + 1].khmer_category() == OT_Ra)
{
- for (unsigned int j = 0; j < pref_len; j++)
- info[i++].mask |= khmer_plan->mask_array[PREF];
+ for (unsigned int j = 0; j < 2; j++)
+ info[i + j].mask |= khmer_plan->mask_array[PREF];
+
+ /* Move the Coeng,Ro sequence to the start. */
+ buffer->merge_clusters (start, i + 2);
+ hb_glyph_info_t t0 = info[i];
+ hb_glyph_info_t t1 = info[i + 1];
+ memmove (&info[start + 2], &info[start], (i - start) * sizeof (info[0]));
+ info[start] = t0;
+ info[start + 1] = t1;
/* Mark the subsequent stuff with 'cfar'. Used in Khmer.
* Read the feature spec.
* U+1784,U+17D2,U+1782,U+17D2,U+179A
*/
if (khmer_plan->mask_array[CFAR])
- for (; i < end; i++)
- info[i].mask |= khmer_plan->mask_array[CFAR];
+ for (unsigned int j = i + 2; j < end; j++)
+ info[j].mask |= khmer_plan->mask_array[CFAR];
- break;
+ num_coengs = 2; /* Done. */
}
}
+
+ /* Reorder left matra piece. */
+ else if (info[i].khmer_position() == POS_PRE_M)
+ {
+ /* Move to the start. */
+ buffer->merge_clusters (start, i + 1);
+ hb_glyph_info_t t = info[i];
+ memmove (&info[start + 1], &info[start], (i - start) * sizeof (info[0]));
+ info[start] = t;
+ }
}
}
{
case broken_cluster: /* We already inserted dotted-circles, so just call the consonant_syllable. */
case consonant_syllable:
- initial_reordering_consonant_syllable (plan, face, buffer, start, end);
+ reorder_consonant_syllable (plan, face, buffer, start, end);
break;
case non_khmer_cluster:
}
static void
-initial_reordering (const hb_ot_shape_plan_t *plan,
- hb_font_t *font,
- hb_buffer_t *buffer)
+reorder (const hb_ot_shape_plan_t *plan,
+ hb_font_t *font,
+ hb_buffer_t *buffer)
{
insert_dotted_circles (plan, font, buffer);
foreach_syllable (buffer, start, end)
initial_reordering_syllable (plan, font->face, buffer, start, end);
-}
-
-static void
-final_reordering_syllable (const hb_ot_shape_plan_t *plan,
- hb_buffer_t *buffer,
- unsigned int start, unsigned int end)
-{
- const khmer_shape_plan_t *khmer_plan = (const khmer_shape_plan_t *) plan->data;
- hb_glyph_info_t *info = buffer->info;
-
-
- /* This function relies heavily on halant glyphs. Lots of ligation
- * and possibly multiple substitutions happened prior to this
- * phase, and that might have messed up our properties. Recover
- * from a particular case of that where we're fairly sure that a
- * class of OT_Coeng is desired but has been lost. */
- if (khmer_plan->virama_glyph)
- {
- unsigned int virama_glyph = khmer_plan->virama_glyph;
- for (unsigned int i = start; i < end; i++)
- if (info[i].codepoint == virama_glyph &&
- _hb_glyph_info_ligated (&info[i]) &&
- _hb_glyph_info_multiplied (&info[i]))
- {
- /* This will make sure that this glyph passes is_coeng() test. */
- info[i].khmer_category() = OT_Coeng;
- _hb_glyph_info_clear_ligated_and_multiplied (&info[i]);
- }
- }
-
-
- /* 4. Final reordering:
- *
- * After the localized forms and basic shaping forms GSUB features have been
- * applied (see below), the shaping engine performs some final glyph
- * reordering before applying all the remaining font features to the entire
- * syllable.
- */
-
- bool try_pref = !!khmer_plan->mask_array[PREF];
-
- /* Find base again */
- unsigned int base;
- for (base = start; base < end; base++)
- if (info[base].khmer_position() >= POS_BASE_C)
- {
- if (try_pref && base + 1 < end)
- {
- for (unsigned int i = base + 1; i < end; i++)
- if ((info[i].mask & khmer_plan->mask_array[PREF]) != 0)
- {
- if (!(_hb_glyph_info_substituted (&info[i]) &&
- _hb_glyph_info_ligated_and_didnt_multiply (&info[i])))
- {
- /* Ok, this was a 'pref' candidate but didn't form any.
- * Base is around here... */
- base = i;
- while (base < end && is_coeng (info[base]))
- base++;
- info[base].khmer_position() = POS_BASE_C;
-
- try_pref = false;
- }
- break;
- }
- }
-
- if (start < base && info[base].khmer_position() > POS_BASE_C)
- base--;
- break;
- }
- if (base == end && start < base &&
- is_one_of (info[base - 1], FLAG (OT_ZWJ)))
- base--;
- if (base < end)
- while (start < base &&
- is_one_of (info[base], (FLAG (OT_N) | FLAG (OT_Coeng))))
- base--;
-
-
- /* o Reorder matras:
- *
- * If a pre-base matra character had been reordered before applying basic
- * features, the glyph can be moved closer to the main consonant based on
- * whether half-forms had been formed. Actual position for the matra is
- * defined as “after last standalone halant glyph, after initial matra
- * position and before the main consonant”. If ZWJ or ZWNJ follow this
- * halant, position is moved after it.
- */
-
- if (start + 1 < end && start < base) /* Otherwise there can't be any pre-base matra characters. */
- {
- /* If we lost track of base, alas, position before last thingy. */
- unsigned int new_pos = base == end ? base - 2 : base - 1;
-
- while (new_pos > start &&
- !(is_one_of (info[new_pos], (FLAG (OT_M) | FLAG (OT_Coeng)))))
- new_pos--;
-
- /* If we found no Halant we are done.
- * Otherwise only proceed if the Halant does
- * not belong to the Matra itself! */
- if (is_coeng (info[new_pos]) &&
- info[new_pos].khmer_position() != POS_PRE_M)
- {
- /* -> If ZWJ or ZWNJ follow this halant, position is moved after it. */
- if (new_pos + 1 < end && is_joiner (info[new_pos + 1]))
- new_pos++;
- }
- else
- new_pos = start; /* No move. */
-
- if (start < new_pos && info[new_pos].khmer_position () != POS_PRE_M)
- {
- /* Now go see if there's actually any matras... */
- for (unsigned int i = new_pos; i > start; i--)
- if (info[i - 1].khmer_position () == POS_PRE_M)
- {
- unsigned int old_pos = i - 1;
- if (old_pos < base && base <= new_pos) /* Shouldn't actually happen. */
- base--;
-
- hb_glyph_info_t tmp = info[old_pos];
- memmove (&info[old_pos], &info[old_pos + 1], (new_pos - old_pos) * sizeof (info[0]));
- info[new_pos] = tmp;
-
- /* Note: this merge_clusters() is intentionally *after* the reordering.
- * Indic matra reordering is special and tricky... */
- buffer->merge_clusters (new_pos, MIN (end, base + 1));
-
- new_pos--;
- }
- } else {
- for (unsigned int i = start; i < base; i++)
- if (info[i].khmer_position () == POS_PRE_M) {
- buffer->merge_clusters (i, MIN (end, base + 1));
- break;
- }
- }
- }
-
-
- /* o Reorder pre-base-reordering consonants:
- *
- * If a pre-base-reordering consonant is found, reorder it according to
- * the following rules:
- */
-
- if (try_pref && base + 1 < end) /* Otherwise there can't be any pre-base-reordering Ra. */
- {
- for (unsigned int i = base + 1; i < end; i++)
- if ((info[i].mask & khmer_plan->mask_array[PREF]) != 0)
- {
- /* 1. Only reorder a glyph produced by substitution during application
- * of the <pref> feature. (Note that a font may shape a Ra consonant with
- * the feature generally but block it in certain contexts.)
- */
- /* Note: We just check that something got substituted. We don't check that
- * the <pref> feature actually did it...
- *
- * Reorder pref only if it ligated. */
- if (_hb_glyph_info_ligated_and_didnt_multiply (&info[i]))
- {
- /*
- * 2. Try to find a target position the same way as for pre-base matra.
- * If it is found, reorder pre-base consonant glyph.
- *
- * 3. If position is not found, reorder immediately before main
- * consonant.
- */
-
- unsigned int new_pos = base;
- while (new_pos > start &&
- !(is_one_of (info[new_pos - 1], FLAG(OT_M) | FLAG (OT_Coeng))))
- new_pos--;
-
- /* In Khmer coeng model, a H,Ra can go *after* matras. If it goes after a
- * split matra, it should be reordered to *before* the left part of such matra. */
- if (new_pos > start && info[new_pos - 1].khmer_category() == OT_M)
- {
- unsigned int old_pos = i;
- for (unsigned int j = base + 1; j < old_pos; j++)
- if (info[j].khmer_category() == OT_M)
- {
- new_pos--;
- break;
- }
- }
-
- if (new_pos > start && is_coeng (info[new_pos - 1]))
- {
- /* -> If ZWJ or ZWNJ follow this halant, position is moved after it. */
- if (new_pos < end && is_joiner (info[new_pos]))
- new_pos++;
- }
-
- {
- unsigned int old_pos = i;
-
- buffer->merge_clusters (new_pos, old_pos + 1);
- hb_glyph_info_t tmp = info[old_pos];
- memmove (&info[new_pos + 1], &info[new_pos], (old_pos - new_pos) * sizeof (info[0]));
- info[new_pos] = tmp;
-
- if (new_pos <= base && base < old_pos)
- base++;
- }
- }
-
- break;
- }
- }
-
-
- /*
- * Finish off the clusters and go home!
- */
- if (hb_options ().uniscribe_bug_compatible)
- {
- /* Uniscribe merges the entire syllable into a single cluster... Except for Tamil & Sinhala.
- * This means, half forms are submerged into the main consonant's cluster.
- * This is unnecessary, and makes cursor positioning harder, but that's what
- * Uniscribe does. */
- buffer->merge_clusters (start, end);
- }
-}
-
-
-static void
-final_reordering (const hb_ot_shape_plan_t *plan,
- hb_font_t *font HB_UNUSED,
- hb_buffer_t *buffer)
-{
- unsigned int count = buffer->len;
- if (unlikely (!count)) return;
-
- foreach_syllable (buffer, start, end)
- final_reordering_syllable (plan, buffer, start, end);
HB_BUFFER_DEALLOCATE_VAR (buffer, khmer_category);
HB_BUFFER_DEALLOCATE_VAR (buffer, khmer_position);
}
-
static void
clear_syllables (const hb_ot_shape_plan_t *plan HB_UNUSED,
hb_font_t *font HB_UNUSED,
hb_buffer_t *buffer)
{
+ /* TODO: In USE, we clear syllables right after reorder. Figure out
+ * what Uniscribe does. */
hb_glyph_info_t *info = buffer->info;
unsigned int count = buffer->len;
for (unsigned int i = 0; i < count; i++)
projects / platform / upstream / libHarfBuzzSharp.git / commitdiff