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authorEskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@qt.io>2023-02-27 12:11:51 +0100
committerQt Cherry-pick Bot <cherrypick_bot@qt-project.org>2023-03-02 05:21:49 +0000
commit7f8020f1f7177d8f3a626e0b746f07dd7727b7e6 (patch)
tree8cdf4986c75789e01b7538a16d47e5452d439732 /src/3rdparty/harfbuzz-ng/src/hb-ot-shaper-thai.cc
parent474e2c9208a9cc7398b1882dd73b4034da6d44b6 (diff)
downloadqtbase-7f8020f1f7177d8f3a626e0b746f07dd7727b7e6.tar.gz
Update Harfbuzz to 7.0.1
This is the 6.4-specific update of Harfbuzz, since Harfbuzz was currently on an older version in 6.4 compared to other branches. This also backports the change to the qtextlayout test that was done on other branches for the 6.0.0 update. Fixes: QTBUG-111535 Change-Id: Ie8217f1541a02d3800142b88cf0007be0ed0d1e2 Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io> (cherry picked from commit 13549fa7c2d27ba588471f97a640f4dbcf86b10c) Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
Diffstat (limited to 'src/3rdparty/harfbuzz-ng/src/hb-ot-shaper-thai.cc')
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+/*
+ * Copyright © 2010,2012 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.hh"
+
+
+/* Thai / Lao shaper */
+
+
+/* PUA shaping */
+
+
+enum thai_consonant_type_t
+{
+ NC,
+ AC,
+ RC,
+ DC,
+ NOT_CONSONANT,
+ NUM_CONSONANT_TYPES = NOT_CONSONANT
+};
+
+static thai_consonant_type_t
+get_consonant_type (hb_codepoint_t u)
+{
+ if (u == 0x0E1Bu || u == 0x0E1Du || u == 0x0E1Fu/* || u == 0x0E2Cu*/)
+ return AC;
+ if (u == 0x0E0Du || u == 0x0E10u)
+ return RC;
+ if (u == 0x0E0Eu || u == 0x0E0Fu)
+ return DC;
+ if (hb_in_range<hb_codepoint_t> (u, 0x0E01u, 0x0E2Eu))
+ return NC;
+ return NOT_CONSONANT;
+}
+
+
+enum thai_mark_type_t
+{
+ AV,
+ BV,
+ T,
+ NOT_MARK,
+ NUM_MARK_TYPES = NOT_MARK
+};
+
+static thai_mark_type_t
+get_mark_type (hb_codepoint_t u)
+{
+ if (u == 0x0E31u || hb_in_range<hb_codepoint_t> (u, 0x0E34u, 0x0E37u) ||
+ u == 0x0E47u || hb_in_range<hb_codepoint_t> (u, 0x0E4Du, 0x0E4Eu))
+ return AV;
+ if (hb_in_range<hb_codepoint_t> (u, 0x0E38u, 0x0E3Au))
+ return BV;
+ if (hb_in_range<hb_codepoint_t> (u, 0x0E48u, 0x0E4Cu))
+ return T;
+ return NOT_MARK;
+}
+
+
+enum thai_action_t
+{
+ NOP,
+ SD, /* Shift combining-mark down */
+ SL, /* Shift combining-mark left */
+ SDL, /* Shift combining-mark down-left */
+ RD /* Remove descender from base */
+};
+
+static hb_codepoint_t
+thai_pua_shape (hb_codepoint_t u, thai_action_t action, hb_font_t *font)
+{
+ struct thai_pua_mapping_t {
+ uint16_t u;
+ uint16_t win_pua;
+ uint16_t mac_pua;
+ } const *pua_mappings = nullptr;
+ static const thai_pua_mapping_t SD_mappings[] = {
+ {0x0E48u, 0xF70Au, 0xF88Bu}, /* MAI EK */
+ {0x0E49u, 0xF70Bu, 0xF88Eu}, /* MAI THO */
+ {0x0E4Au, 0xF70Cu, 0xF891u}, /* MAI TRI */
+ {0x0E4Bu, 0xF70Du, 0xF894u}, /* MAI CHATTAWA */
+ {0x0E4Cu, 0xF70Eu, 0xF897u}, /* THANTHAKHAT */
+ {0x0E38u, 0xF718u, 0xF89Bu}, /* SARA U */
+ {0x0E39u, 0xF719u, 0xF89Cu}, /* SARA UU */
+ {0x0E3Au, 0xF71Au, 0xF89Du}, /* PHINTHU */
+ {0x0000u, 0x0000u, 0x0000u}
+ };
+ static const thai_pua_mapping_t SDL_mappings[] = {
+ {0x0E48u, 0xF705u, 0xF88Cu}, /* MAI EK */
+ {0x0E49u, 0xF706u, 0xF88Fu}, /* MAI THO */
+ {0x0E4Au, 0xF707u, 0xF892u}, /* MAI TRI */
+ {0x0E4Bu, 0xF708u, 0xF895u}, /* MAI CHATTAWA */
+ {0x0E4Cu, 0xF709u, 0xF898u}, /* THANTHAKHAT */
+ {0x0000u, 0x0000u, 0x0000u}
+ };
+ static const thai_pua_mapping_t SL_mappings[] = {
+ {0x0E48u, 0xF713u, 0xF88Au}, /* MAI EK */
+ {0x0E49u, 0xF714u, 0xF88Du}, /* MAI THO */
+ {0x0E4Au, 0xF715u, 0xF890u}, /* MAI TRI */
+ {0x0E4Bu, 0xF716u, 0xF893u}, /* MAI CHATTAWA */
+ {0x0E4Cu, 0xF717u, 0xF896u}, /* THANTHAKHAT */
+ {0x0E31u, 0xF710u, 0xF884u}, /* MAI HAN-AKAT */
+ {0x0E34u, 0xF701u, 0xF885u}, /* SARA I */
+ {0x0E35u, 0xF702u, 0xF886u}, /* SARA II */
+ {0x0E36u, 0xF703u, 0xF887u}, /* SARA UE */
+ {0x0E37u, 0xF704u, 0xF888u}, /* SARA UEE */
+ {0x0E47u, 0xF712u, 0xF889u}, /* MAITAIKHU */
+ {0x0E4Du, 0xF711u, 0xF899u}, /* NIKHAHIT */
+ {0x0000u, 0x0000u, 0x0000u}
+ };
+ static const thai_pua_mapping_t RD_mappings[] = {
+ {0x0E0Du, 0xF70Fu, 0xF89Au}, /* YO YING */
+ {0x0E10u, 0xF700u, 0xF89Eu}, /* THO THAN */
+ {0x0000u, 0x0000u, 0x0000u}
+ };
+
+ switch (action) {
+ case NOP: return u;
+ case SD: pua_mappings = SD_mappings; break;
+ case SDL: pua_mappings = SDL_mappings; break;
+ case SL: pua_mappings = SL_mappings; break;
+ case RD: pua_mappings = RD_mappings; break;
+ }
+ for (; pua_mappings->u; pua_mappings++)
+ if (pua_mappings->u == u)
+ {
+ hb_codepoint_t glyph;
+ if (hb_font_get_glyph (font, pua_mappings->win_pua, 0, &glyph))
+ return pua_mappings->win_pua;
+ if (hb_font_get_glyph (font, pua_mappings->mac_pua, 0, &glyph))
+ return pua_mappings->mac_pua;
+ break;
+ }
+ return u;
+}
+
+
+static enum thai_above_state_t
+{ /* Cluster above looks like: */
+ T0, /* ⣤ */
+ T1, /* ⣼ */
+ T2, /* ⣾ */
+ T3, /* ⣿ */
+ NUM_ABOVE_STATES
+} thai_above_start_state[NUM_CONSONANT_TYPES + 1/* For NOT_CONSONANT */] =
+{
+ T0, /* NC */
+ T1, /* AC */
+ T0, /* RC */
+ T0, /* DC */
+ T3, /* NOT_CONSONANT */
+};
+
+static const struct thai_above_state_machine_edge_t {
+ thai_action_t action;
+ thai_above_state_t next_state;
+} thai_above_state_machine[NUM_ABOVE_STATES][NUM_MARK_TYPES] =
+{ /*AV*/ /*BV*/ /*T*/
+/*T0*/ {{NOP,T3}, {NOP,T0}, {SD, T3}},
+/*T1*/ {{SL, T2}, {NOP,T1}, {SDL,T2}},
+/*T2*/ {{NOP,T3}, {NOP,T2}, {SL, T3}},
+/*T3*/ {{NOP,T3}, {NOP,T3}, {NOP,T3}},
+};
+
+
+static enum thai_below_state_t
+{
+ B0, /* No descender */
+ B1, /* Removable descender */
+ B2, /* Strict descender */
+ NUM_BELOW_STATES
+} thai_below_start_state[NUM_CONSONANT_TYPES + 1/* For NOT_CONSONANT */] =
+{
+ B0, /* NC */
+ B0, /* AC */
+ B1, /* RC */
+ B2, /* DC */
+ B2, /* NOT_CONSONANT */
+};
+
+static const struct thai_below_state_machine_edge_t {
+ thai_action_t action;
+ thai_below_state_t next_state;
+} thai_below_state_machine[NUM_BELOW_STATES][NUM_MARK_TYPES] =
+{ /*AV*/ /*BV*/ /*T*/
+/*B0*/ {{NOP,B0}, {NOP,B2}, {NOP, B0}},
+/*B1*/ {{NOP,B1}, {RD, B2}, {NOP, B1}},
+/*B2*/ {{NOP,B2}, {SD, B2}, {NOP, B2}},
+};
+
+
+static void
+do_thai_pua_shaping (const hb_ot_shape_plan_t *plan HB_UNUSED,
+ hb_buffer_t *buffer,
+ hb_font_t *font)
+{
+#ifdef HB_NO_OT_SHAPER_THAI_FALLBACK
+ return;
+#endif
+
+ thai_above_state_t above_state = thai_above_start_state[NOT_CONSONANT];
+ thai_below_state_t below_state = thai_below_start_state[NOT_CONSONANT];
+ unsigned int base = 0;
+
+ hb_glyph_info_t *info = buffer->info;
+ unsigned int count = buffer->len;
+ for (unsigned int i = 0; i < count; i++)
+ {
+ thai_mark_type_t mt = get_mark_type (info[i].codepoint);
+
+ if (mt == NOT_MARK) {
+ thai_consonant_type_t ct = get_consonant_type (info[i].codepoint);
+ above_state = thai_above_start_state[ct];
+ below_state = thai_below_start_state[ct];
+ base = i;
+ continue;
+ }
+
+ const thai_above_state_machine_edge_t &above_edge = thai_above_state_machine[above_state][mt];
+ const thai_below_state_machine_edge_t &below_edge = thai_below_state_machine[below_state][mt];
+ above_state = above_edge.next_state;
+ below_state = below_edge.next_state;
+
+ /* At least one of the above/below actions is NOP. */
+ thai_action_t action = above_edge.action != NOP ? above_edge.action : below_edge.action;
+
+ buffer->unsafe_to_break (base, i);
+ if (action == RD)
+ info[base].codepoint = thai_pua_shape (info[base].codepoint, action, font);
+ else
+ info[i].codepoint = thai_pua_shape (info[i].codepoint, action, font);
+ }
+}
+
+
+static void
+preprocess_text_thai (const hb_ot_shape_plan_t *plan,
+ hb_buffer_t *buffer,
+ hb_font_t *font)
+{
+ /* This function implements the shaping logic documented here:
+ *
+ * https://linux.thai.net/~thep/th-otf/shaping.html
+ *
+ * The first shaping rule listed there is needed even if the font has Thai
+ * OpenType tables. The rest do fallback positioning based on PUA codepoints.
+ * We implement that only if there exist no Thai GSUB in the font.
+ */
+
+ /* The following is NOT specified in the MS OT Thai spec, however, it seems
+ * to be what Uniscribe and other engines implement. According to Eric Muller:
+ *
+ * When you have a SARA AM, decompose it in NIKHAHIT + SARA AA, *and* move the
+ * NIKHAHIT backwards over any above-base marks.
+ *
+ * <0E14, 0E4B, 0E33> -> <0E14, 0E4D, 0E4B, 0E32>
+ *
+ * This reordering is legit only when the NIKHAHIT comes from a SARA AM, not
+ * when it's there to start with. The string <0E14, 0E4B, 0E4D> is probably
+ * not what a user wanted, but the rendering is nevertheless nikhahit above
+ * chattawa.
+ *
+ * Same for Lao.
+ *
+ * Note:
+ *
+ * Uniscribe also does some below-marks reordering. Namely, it positions U+0E3A
+ * after U+0E38 and U+0E39. We do that by modifying the ccc for U+0E3A.
+ * See unicode->modified_combining_class (). Lao does NOT have a U+0E3A
+ * equivalent.
+ */
+
+
+ /*
+ * Here are the characters of significance:
+ *
+ * Thai Lao
+ * SARA AM: U+0E33 U+0EB3
+ * SARA AA: U+0E32 U+0EB2
+ * Nikhahit: U+0E4D U+0ECD
+ *
+ * Testing shows that Uniscribe reorder the following marks:
+ * Thai: <0E31,0E34..0E37, 0E47..0E4E>
+ * Lao: <0EB1,0EB4..0EB7,0EBB,0EC8..0ECD>
+ *
+ * Note how the Lao versions are the same as Thai + 0x80.
+ */
+
+ /* We only get one script at a time, so a script-agnostic implementation
+ * is adequate here. */
+#define IS_SARA_AM(x) (((x) & ~0x0080u) == 0x0E33u)
+#define NIKHAHIT_FROM_SARA_AM(x) ((x) - 0x0E33u + 0x0E4Du)
+#define SARA_AA_FROM_SARA_AM(x) ((x) - 1)
+#define IS_ABOVE_BASE_MARK(x) (hb_in_ranges<hb_codepoint_t> ((x) & ~0x0080u, 0x0E34u, 0x0E37u, 0x0E47u, 0x0E4Eu, 0x0E31u, 0x0E31u, 0x0E3Bu, 0x0E3Bu))
+
+ buffer->clear_output ();
+ unsigned int count = buffer->len;
+ for (buffer->idx = 0; buffer->idx < count /* No need for: && buffer->successful */;)
+ {
+ hb_codepoint_t u = buffer->cur().codepoint;
+ if (likely (!IS_SARA_AM (u)))
+ {
+ if (unlikely (!buffer->next_glyph ())) break;
+ continue;
+ }
+
+ /* Is SARA AM. Decompose and reorder. */
+ (void) buffer->output_glyph (NIKHAHIT_FROM_SARA_AM (u));
+ _hb_glyph_info_set_continuation (&buffer->prev());
+ if (unlikely (!buffer->replace_glyph (SARA_AA_FROM_SARA_AM (u)))) break;
+
+ /* Make Nikhahit be recognized as a ccc=0 mark when zeroing widths. */
+ unsigned int end = buffer->out_len;
+ _hb_glyph_info_set_general_category (&buffer->out_info[end - 2], HB_UNICODE_GENERAL_CATEGORY_NON_SPACING_MARK);
+
+ /* Ok, let's see... */
+ unsigned int start = end - 2;
+ while (start > 0 && IS_ABOVE_BASE_MARK (buffer->out_info[start - 1].codepoint))
+ start--;
+
+ if (start + 2 < end)
+ {
+ /* Move Nikhahit (end-2) to the beginning */
+ buffer->merge_out_clusters (start, end);
+ hb_glyph_info_t t = buffer->out_info[end - 2];
+ memmove (buffer->out_info + start + 1,
+ buffer->out_info + start,
+ sizeof (buffer->out_info[0]) * (end - start - 2));
+ buffer->out_info[start] = t;
+ }
+ else
+ {
+ /* Since we decomposed, and NIKHAHIT is combining, merge clusters with the
+ * previous cluster. */
+ if (start && buffer->cluster_level == HB_BUFFER_CLUSTER_LEVEL_MONOTONE_GRAPHEMES)
+ buffer->merge_out_clusters (start - 1, end);
+ }
+ }
+ buffer->sync ();
+
+ /* If font has Thai GSUB, we are done. */
+ if (plan->props.script == HB_SCRIPT_THAI && !plan->map.found_script[0])
+ do_thai_pua_shaping (plan, buffer, font);
+}
+
+const hb_ot_shaper_t _hb_ot_shaper_thai =
+{
+ nullptr, /* collect_features */
+ nullptr, /* override_features */
+ nullptr, /* data_create */
+ nullptr, /* data_destroy */
+ preprocess_text_thai,
+ nullptr, /* postprocess_glyphs */
+ nullptr, /* decompose */
+ nullptr, /* compose */
+ nullptr, /* setup_masks */
+ nullptr, /* reorder_marks */
+ HB_TAG_NONE, /* gpos_tag */
+ HB_OT_SHAPE_NORMALIZATION_MODE_DEFAULT,
+ HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF_LATE,
+ false,/* fallback_position */
+};
+
+
+#endif