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diff --git a/Build/source/libs/harfbuzz/harfbuzz-src/src/hb-ot-shape-complex-khmer.cc b/Build/source/libs/harfbuzz/harfbuzz-src/src/hb-ot-shape-complex-khmer.cc
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+++ b/Build/source/libs/harfbuzz/harfbuzz-src/src/hb-ot-shape-complex-khmer.cc
@@ -0,0 +1,945 @@
+/*
+ * 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-ot-shape-complex-indic-private.hh"
+#include "hb-ot-layout-private.hh"
+
+/* buffer var allocations */
+#define khmer_category() complex_var_u8_0() /* khmer_category_t */
+#define khmer_position() complex_var_u8_1() /* khmer_position_t */
+
+
+/*
+ * Khmer shaper.
+ */
+
+typedef indic_category_t khmer_category_t;
+typedef indic_position_t khmer_position_t;
+
+
+static inline khmer_position_t
+matra_position (khmer_position_t side)
+{
+ switch ((int) side)
+ {
+ case POS_PRE_C:
+ return POS_PRE_M;
+
+ case POS_POST_C:
+ case POS_ABOVE_C:
+ case POS_BELOW_C:
+ return POS_AFTER_POST;
+
+ default:
+ return side;
+ };
+}
+
+static inline bool
+is_one_of (const hb_glyph_info_t &info, unsigned int flags)
+{
+ /* If it ligated, all bets are off. */
+ if (_hb_glyph_info_ligated (&info)) return false;
+ return !!(FLAG_UNSAFE (info.khmer_category()) & flags);
+}
+
+static inline bool
+is_joiner (const hb_glyph_info_t &info)
+{
+ return is_one_of (info, JOINER_FLAGS);
+}
+
+static inline bool
+is_consonant (const hb_glyph_info_t &info)
+{
+ return is_one_of (info, CONSONANT_FLAGS | FLAG (OT_V));
+}
+
+static inline bool
+is_coeng (const hb_glyph_info_t &info)
+{
+ return is_one_of (info, FLAG (OT_Coeng));
+}
+
+static inline void
+set_khmer_properties (hb_glyph_info_t &info)
+{
+ hb_codepoint_t u = info.codepoint;
+ unsigned int type = hb_indic_get_categories (u);
+ khmer_category_t cat = (khmer_category_t) (type & 0x7Fu);
+ khmer_position_t pos = (khmer_position_t) (type >> 8);
+
+
+ /*
+ * Re-assign category
+ */
+
+ if (unlikely (u == 0x17C6u)) cat = OT_N; /* Khmer Bindu doesn't like to be repositioned. */
+ else if (unlikely (hb_in_range<hb_codepoint_t> (u, 0x17CDu, 0x17D1u) ||
+ u == 0x17CBu || u == 0x17D3u || u == 0x17DDu)) /* Khmer Various signs */
+ {
+ /* These can occur mid-syllable (eg. before matras), even though Unicode marks them as Syllable_Modifier.
+ * https://github.com/roozbehp/unicode-data/issues/5 */
+ cat = OT_M;
+ pos = POS_ABOVE_C;
+ }
+ else if (unlikely (hb_in_range<hb_codepoint_t> (u, 0x2010u, 0x2011u))) cat = OT_PLACEHOLDER;
+ else if (unlikely (u == 0x25CCu)) cat = OT_DOTTEDCIRCLE;
+
+
+ /*
+ * Re-assign position.
+ */
+
+ if ((FLAG_UNSAFE (cat) & CONSONANT_FLAGS))
+ {
+ pos = POS_BASE_C;
+ if (u == 0x179Au)
+ cat = OT_Ra;
+ }
+ else if (cat == OT_M)
+ {
+ pos = matra_position (pos);
+ }
+ else if ((FLAG_UNSAFE (cat) & (FLAG (OT_SM) | FLAG (OT_A) | FLAG (OT_Symbol))))
+ {
+ pos = POS_SMVD;
+ }
+
+ info.khmer_category() = cat;
+ info.khmer_position() = pos;
+}
+
+/*
+ * Things above this line should ideally be moved to the Indic table itself.
+ */
+
+
+/*
+ * Khmer shaper.
+ */
+
+struct feature_list_t {
+ hb_tag_t tag;
+ hb_ot_map_feature_flags_t flags;
+};
+
+static const feature_list_t
+khmer_features[] =
+{
+ /*
+ * Basic features.
+ * These features are applied in order, one at a time, after initial_reordering.
+ */
+ {HB_TAG('p','r','e','f'), F_NONE},
+ {HB_TAG('b','l','w','f'), F_NONE},
+ {HB_TAG('a','b','v','f'), F_NONE},
+ {HB_TAG('p','s','t','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.
+ */
+ {HB_TAG('p','r','e','s'), F_GLOBAL},
+ {HB_TAG('a','b','v','s'), F_GLOBAL},
+ {HB_TAG('b','l','w','s'), F_GLOBAL},
+ {HB_TAG('p','s','t','s'), F_GLOBAL},
+ /* Positioning features, though we don't care about the types. */
+ {HB_TAG('d','i','s','t'), F_GLOBAL},
+ {HB_TAG('a','b','v','m'), F_GLOBAL},
+ {HB_TAG('b','l','w','m'), F_GLOBAL},
+};
+
+/*
+ * Must be in the same order as the khmer_features array.
+ */
+enum {
+ PREF,
+ BLWF,
+ ABVF,
+ PSTF,
+ CFAR,
+
+ _PRES,
+ _ABVS,
+ _BLWS,
+ _PSTS,
+ _DIST,
+ _ABVM,
+ _BLWM,
+
+ KHMER_NUM_FEATURES,
+ KHMER_BASIC_FEATURES = _PRES /* Don't forget to update this! */
+};
+
+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
+clear_syllables (const hb_ot_shape_plan_t *plan,
+ hb_font_t *font,
+ hb_buffer_t *buffer);
+
+static void
+collect_features_khmer (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'));
+
+
+ unsigned int i = 0;
+ map->add_gsub_pause (initial_reordering);
+ 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);
+ }
+
+ map->add_global_bool_feature (HB_TAG('c','a','l','t'));
+ map->add_global_bool_feature (HB_TAG('c','l','i','g'));
+
+ map->add_gsub_pause (clear_syllables);
+}
+
+static void
+override_features_khmer (hb_ot_shape_planner_t *plan)
+{
+ /* Uniscribe does not apply 'kern' in Khmer. */
+ if (hb_options ().uniscribe_bug_compatible)
+ {
+ plan->map.add_feature (HB_TAG('k','e','r','n'), 0, F_GLOBAL);
+ }
+
+ plan->map.add_feature (HB_TAG('l','i','g','a'), 0, F_GLOBAL);
+}
+
+
+struct would_substitute_feature_t
+{
+ inline void init (const hb_ot_map_t *map, hb_tag_t feature_tag, bool zero_context_)
+ {
+ zero_context = zero_context_;
+ map->get_stage_lookups (0/*GSUB*/,
+ map->get_feature_stage (0/*GSUB*/, feature_tag),
+ &lookups, &count);
+ }
+
+ inline bool would_substitute (const hb_codepoint_t *glyphs,
+ unsigned int glyphs_count,
+ hb_face_t *face) const
+ {
+ for (unsigned int i = 0; i < count; i++)
+ if (hb_ot_layout_lookup_would_substitute_fast (face, lookups[i].index, glyphs, glyphs_count, zero_context))
+ return true;
+ return false;
+ }
+
+ private:
+ const hb_ot_map_t::lookup_map_t *lookups;
+ unsigned int count;
+ bool zero_context;
+};
+
+struct khmer_shape_plan_t
+{
+ ASSERT_POD ();
+
+ inline bool get_virama_glyph (hb_font_t *font, hb_codepoint_t *pglyph) const
+ {
+ hb_codepoint_t glyph = virama_glyph;
+ if (unlikely (virama_glyph == (hb_codepoint_t) -1))
+ {
+ if (!font->get_nominal_glyph (0x17D2u, &glyph))
+ glyph = 0;
+ /* Technically speaking, the spec says we should apply 'locl' to virama too.
+ * Maybe one day... */
+
+ /* Our get_nominal_glyph() function needs a font, so we can't get the virama glyph
+ * during shape planning... Instead, overwrite it here. It's safe. Don't worry! */
+ virama_glyph = glyph;
+ }
+
+ *pglyph = glyph;
+ return glyph != 0;
+ }
+
+ mutable hb_codepoint_t virama_glyph;
+
+ would_substitute_feature_t pref;
+
+ hb_mask_t mask_array[KHMER_NUM_FEATURES];
+};
+
+static void *
+data_create_khmer (const hb_ot_shape_plan_t *plan)
+{
+ khmer_shape_plan_t *khmer_plan = (khmer_shape_plan_t *) calloc (1, sizeof (khmer_shape_plan_t));
+ if (unlikely (!khmer_plan))
+ return nullptr;
+
+ khmer_plan->virama_glyph = (hb_codepoint_t) -1;
+
+ khmer_plan->pref.init (&plan->map, HB_TAG('p','r','e','f'), true);
+
+ for (unsigned int i = 0; i < ARRAY_LENGTH (khmer_plan->mask_array); i++)
+ khmer_plan->mask_array[i] = (khmer_features[i].flags & F_GLOBAL) ?
+ 0 : plan->map.get_1_mask (khmer_features[i].tag);
+
+ return khmer_plan;
+}
+
+static void
+data_destroy_khmer (void *data)
+{
+ free (data);
+}
+
+
+enum syllable_type_t {
+ consonant_syllable,
+ broken_cluster,
+ non_khmer_cluster,
+};
+
+#include "hb-ot-shape-complex-khmer-machine.hh"
+
+static void
+setup_masks_khmer (const hb_ot_shape_plan_t *plan HB_UNUSED,
+ hb_buffer_t *buffer,
+ hb_font_t *font HB_UNUSED)
+{
+ HB_BUFFER_ALLOCATE_VAR (buffer, khmer_category);
+ HB_BUFFER_ALLOCATE_VAR (buffer, khmer_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_khmer_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);
+ foreach_syllable (buffer, start, end)
+ 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://www.microsoft.com/typography/otfntdev/devanot/shaping.aspx */
+
+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)
+{
+ 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 (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 (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_H &&
+ 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 (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;
+ }
+
+ /* 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 */
+
+ {
+ 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++)
+ info[i].mask |= mask;
+ }
+
+ unsigned int pref_len = 2;
+ if (khmer_plan->mask_array[PREF] && base + pref_len < end)
+ {
+ /* 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))
+ {
+ for (unsigned int j = 0; j < pref_len; j++)
+ info[i++].mask |= khmer_plan->mask_array[PREF];
+
+ /* Mark the subsequent stuff with 'cfar'. Used in Khmer.
+ * Read the feature spec.
+ * This allows distinguishing the following cases with MS Khmer fonts:
+ * U+1784,U+17D2,U+179A,U+17D2,U+1782
+ * 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];
+
+ break;
+ }
+ }
+ }
+}
+
+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 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);
+ break;
+
+ case non_khmer_cluster:
+ break;
+ }
+}
+
+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_nominal_glyph (0x25CCu, &dottedcircle_glyph))
+ return;
+
+ hb_glyph_info_t dottedcircle = {0};
+ dottedcircle.codepoint = 0x25CCu;
+ set_khmer_properties (dottedcircle);
+ dottedcircle.codepoint = dottedcircle_glyph;
+
+ buffer->clear_output ();
+
+ buffer->idx = 0;
+ unsigned int last_syllable = 0;
+ while (buffer->idx < buffer->len && !buffer->in_error)
+ {
+ 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 ginfo = dottedcircle;
+ ginfo.cluster = buffer->cur().cluster;
+ ginfo.mask = buffer->cur().mask;
+ ginfo.syllable() = buffer->cur().syllable();
+ /* TODO Set glyph_props? */
+
+ /* Insert dottedcircle after possible Repha. */
+ while (buffer->idx < buffer->len && !buffer->in_error &&
+ last_syllable == buffer->cur().syllable() &&
+ buffer->cur().khmer_category() == OT_Repha)
+ buffer->next_glyph ();
+
+ buffer->output_info (ginfo);
+ }
+ 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);
+
+ 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_H 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_H;
+ _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)
+{
+ hb_glyph_info_t *info = buffer->info;
+ unsigned int count = buffer->len;
+ for (unsigned int i = 0; i < count; i++)
+ info[i].syllable() = 0;
+}
+
+
+static bool
+decompose_khmer (const hb_ot_shape_normalize_context_t *c,
+ hb_codepoint_t ab,
+ hb_codepoint_t *a,
+ hb_codepoint_t *b)
+{
+ switch (ab)
+ {
+ /*
+ * Decompose split matras that don't have Unicode decompositions.
+ */
+
+ /* Khmer */
+ case 0x17BEu : *a = 0x17C1u; *b= 0x17BEu; return true;
+ case 0x17BFu : *a = 0x17C1u; *b= 0x17BFu; return true;
+ case 0x17C0u : *a = 0x17C1u; *b= 0x17C0u; return true;
+ case 0x17C4u : *a = 0x17C1u; *b= 0x17C4u; return true;
+ case 0x17C5u : *a = 0x17C1u; *b= 0x17C5u; return true;
+ }
+
+ return (bool) c->unicode->decompose (ab, a, b);
+}
+
+static bool
+compose_khmer (const hb_ot_shape_normalize_context_t *c,
+ hb_codepoint_t a,
+ hb_codepoint_t b,
+ hb_codepoint_t *ab)
+{
+ /* Avoid recomposing split matras. */
+ if (HB_UNICODE_GENERAL_CATEGORY_IS_MARK (c->unicode->general_category (a)))
+ return false;
+
+ return (bool) c->unicode->compose (a, b, ab);
+}
+
+
+const hb_ot_complex_shaper_t _hb_ot_complex_shaper_khmer =
+{
+ collect_features_khmer,
+ override_features_khmer,
+ data_create_khmer,
+ data_destroy_khmer,
+ nullptr, /* preprocess_text */
+ nullptr, /* postprocess_glyphs */
+ HB_OT_SHAPE_NORMALIZATION_MODE_COMPOSED_DIACRITICS_NO_SHORT_CIRCUIT,
+ decompose_khmer,
+ compose_khmer,
+ setup_masks_khmer,
+ nullptr, /* disable_otl */
+ nullptr, /* reorder_marks */
+ HB_OT_SHAPE_ZERO_WIDTH_MARKS_NONE,
+ false, /* fallback_position */
+};