1366 lines
43 KiB
C++
1366 lines
43 KiB
C++
/*
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* Copyright © 2011,2012 Google, Inc.
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*
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* This is part of HarfBuzz, a text shaping library.
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*
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* Permission is hereby granted, without written agreement and without
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* license or royalty fees, to use, copy, modify, and distribute this
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* software and its documentation for any purpose, provided that the
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* above copyright notice and the following two paragraphs appear in
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* all copies of this software.
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*
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* IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
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* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
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* ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
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* IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
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* DAMAGE.
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*
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* THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
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* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
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* FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
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* ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
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* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
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*
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* Google Author(s): Behdad Esfahbod
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*/
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#include "hb-ot-shape-complex-indic-private.hh"
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#include "hb-ot-layout-private.hh"
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/*
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* Global Indic shaper options.
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*/
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struct indic_options_t
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{
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int initialized : 1;
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int uniscribe_bug_compatible : 1;
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};
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union indic_options_union_t {
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int i;
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indic_options_t opts;
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};
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ASSERT_STATIC (sizeof (int) == sizeof (indic_options_union_t));
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static indic_options_union_t
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indic_options_init (void)
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{
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indic_options_union_t u;
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u.i = 0;
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u.opts.initialized = 1;
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char *c = getenv ("HB_OT_INDIC_OPTIONS");
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u.opts.uniscribe_bug_compatible = c && strstr (c, "uniscribe-bug-compatible");
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return u;
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}
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static inline indic_options_t
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indic_options (void)
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{
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static indic_options_union_t options;
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if (unlikely (!options.i)) {
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/* This is idempotent and threadsafe. */
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options = indic_options_init ();
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}
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return options.opts;
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}
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/*
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* Indic configurations. Note that we do not want to keep every single script-specific
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* behavior in these tables necessarily. This should mainly be used for per-script
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* properties that are cheaper keeping here, than in the code. Ie. if, say, one and
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* only one script has an exception, that one script can be if'ed directly in the code,
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* instead of adding a new flag in these structs.
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*/
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enum base_position_t {
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BASE_POS_FIRST,
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BASE_POS_LAST
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};
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enum reph_position_t {
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REPH_POS_DEFAULT = POS_BEFORE_POST,
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REPH_POS_AFTER_MAIN = POS_AFTER_MAIN,
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REPH_POS_BEFORE_SUB = POS_BEFORE_SUB,
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REPH_POS_AFTER_SUB = POS_AFTER_SUB,
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REPH_POS_BEFORE_POST = POS_BEFORE_POST,
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REPH_POS_AFTER_POST = POS_AFTER_POST
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};
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enum reph_mode_t {
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REPH_MODE_IMPLICIT, /* Reph formed out of initial Ra,H sequence. */
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REPH_MODE_EXPLICIT, /* Reph formed out of initial Ra,H,ZWJ sequence. */
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REPH_MODE_VIS_REPHA, /* Encoded Repha character, no reordering needed. */
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REPH_MODE_LOG_REPHA /* Encoded Repha character, needs reordering. */
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};
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struct indic_config_t
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{
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hb_script_t script;
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bool has_old_spec;
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hb_codepoint_t virama;
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base_position_t base_pos;
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reph_position_t reph_pos;
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reph_mode_t reph_mode;
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};
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static const indic_config_t indic_configs[] =
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{
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/* Default. Should be first. */
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{HB_SCRIPT_INVALID, false, 0,BASE_POS_LAST, REPH_POS_DEFAULT, REPH_MODE_IMPLICIT},
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{HB_SCRIPT_DEVANAGARI,true, 0x094D,BASE_POS_LAST, REPH_POS_BEFORE_POST,REPH_MODE_IMPLICIT},
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{HB_SCRIPT_BENGALI, true, 0x09CD,BASE_POS_LAST, REPH_POS_AFTER_SUB, REPH_MODE_IMPLICIT},
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{HB_SCRIPT_GURMUKHI, true, 0x0A4D,BASE_POS_LAST, REPH_POS_BEFORE_SUB, REPH_MODE_IMPLICIT},
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{HB_SCRIPT_GUJARATI, true, 0x0ACD,BASE_POS_LAST, REPH_POS_BEFORE_POST,REPH_MODE_IMPLICIT},
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{HB_SCRIPT_ORIYA, true, 0x0B4D,BASE_POS_LAST, REPH_POS_AFTER_MAIN, REPH_MODE_IMPLICIT},
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{HB_SCRIPT_TAMIL, true, 0x0BCD,BASE_POS_LAST, REPH_POS_AFTER_POST, REPH_MODE_IMPLICIT},
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{HB_SCRIPT_TELUGU, true, 0x0C4D,BASE_POS_LAST, REPH_POS_AFTER_POST, REPH_MODE_EXPLICIT},
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{HB_SCRIPT_KANNADA, true, 0x0CCD,BASE_POS_LAST, REPH_POS_AFTER_POST, REPH_MODE_IMPLICIT},
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{HB_SCRIPT_MALAYALAM, true, 0x0D4D,BASE_POS_LAST, REPH_POS_AFTER_MAIN, REPH_MODE_LOG_REPHA},
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{HB_SCRIPT_SINHALA, false,0x0DCA,BASE_POS_FIRST,REPH_POS_AFTER_MAIN, REPH_MODE_EXPLICIT},
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{HB_SCRIPT_KHMER, false,0x17D2,BASE_POS_FIRST,REPH_POS_DEFAULT, REPH_MODE_VIS_REPHA},
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/* Myanmar does not have the "old_indic" behavior, even though it has a "new" tag. */
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{HB_SCRIPT_MYANMAR, false, 0x1039,BASE_POS_LAST, REPH_POS_DEFAULT, REPH_MODE_EXPLICIT},
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};
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/*
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* Indic shaper.
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*/
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struct feature_list_t {
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hb_tag_t tag;
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hb_bool_t is_global;
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};
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static const feature_list_t
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indic_features[] =
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{
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/*
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* Basic features.
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* These features are applied in order, one at a time, after initial_reordering.
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*/
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{HB_TAG('n','u','k','t'), true},
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{HB_TAG('a','k','h','n'), true},
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{HB_TAG('r','p','h','f'), false},
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{HB_TAG('r','k','r','f'), true},
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{HB_TAG('p','r','e','f'), false},
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{HB_TAG('h','a','l','f'), false},
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{HB_TAG('b','l','w','f'), false},
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{HB_TAG('a','b','v','f'), false},
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{HB_TAG('p','s','t','f'), false},
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{HB_TAG('c','f','a','r'), false},
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{HB_TAG('c','j','c','t'), true},
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{HB_TAG('v','a','t','u'), true},
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/*
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* Other features.
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* These features are applied all at once, after final_reordering.
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*/
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{HB_TAG('i','n','i','t'), false},
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{HB_TAG('p','r','e','s'), true},
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{HB_TAG('a','b','v','s'), true},
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{HB_TAG('b','l','w','s'), true},
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{HB_TAG('p','s','t','s'), true},
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{HB_TAG('h','a','l','n'), true},
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/* Positioning features, though we don't care about the types. */
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{HB_TAG('d','i','s','t'), true},
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{HB_TAG('a','b','v','m'), true},
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{HB_TAG('b','l','w','m'), true},
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};
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/*
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* Must be in the same order as the indic_features array.
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*/
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enum {
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_NUKT,
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_AKHN,
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RPHF,
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_RKRF,
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PREF,
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HALF,
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BLWF,
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ABVF,
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PSTF,
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CFAR,
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_CJCT,
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_VATU,
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INIT,
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_PRES,
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_ABVS,
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_BLWS,
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_PSTS,
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_HALN,
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_DIST,
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_ABVM,
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_BLWM,
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INDIC_NUM_FEATURES,
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INDIC_BASIC_FEATURES = INIT /* Don't forget to update this! */
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};
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static void
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setup_syllables (const hb_ot_shape_plan_t *plan,
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hb_font_t *font,
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hb_buffer_t *buffer);
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static void
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initial_reordering (const hb_ot_shape_plan_t *plan,
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hb_font_t *font,
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hb_buffer_t *buffer);
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static void
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final_reordering (const hb_ot_shape_plan_t *plan,
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hb_font_t *font,
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hb_buffer_t *buffer);
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static void
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collect_features_indic (hb_ot_shape_planner_t *plan)
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{
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hb_ot_map_builder_t *map = &plan->map;
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/* Do this before any lookups have been applied. */
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map->add_gsub_pause (setup_syllables);
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map->add_bool_feature (HB_TAG('l','o','c','l'));
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/* The Indic specs do not require ccmp, but we apply it here since if
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* there is a use of it, it's typically at the beginning. */
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map->add_bool_feature (HB_TAG('c','c','m','p'));
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unsigned int i = 0;
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map->add_gsub_pause (initial_reordering);
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for (; i < INDIC_BASIC_FEATURES; i++) {
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map->add_bool_feature (indic_features[i].tag, indic_features[i].is_global);
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map->add_gsub_pause (NULL);
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}
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map->add_gsub_pause (final_reordering);
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for (; i < INDIC_NUM_FEATURES; i++) {
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map->add_bool_feature (indic_features[i].tag, indic_features[i].is_global);
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}
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}
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static void
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override_features_indic (hb_ot_shape_planner_t *plan)
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{
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/* Uniscribe does not apply 'kern'. */
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if (indic_options ().uniscribe_bug_compatible)
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plan->map.add_feature (HB_TAG('k','e','r','n'), 0, true);
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plan->map.add_feature (HB_TAG('l','i','g','a'), 0, true);
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}
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struct would_substitute_feature_t
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{
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inline void init (const hb_ot_map_t *map, hb_tag_t feature_tag)
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{
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map->get_stage_lookups (0/*GSUB*/,
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map->get_feature_stage (0/*GSUB*/, feature_tag),
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&lookups, &count);
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}
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inline bool would_substitute (hb_codepoint_t *glyphs,
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unsigned int glyphs_count,
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bool zero_context,
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hb_face_t *face) const
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{
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for (unsigned int i = 0; i < count; i++)
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if (hb_ot_layout_lookup_would_substitute_fast (face, lookups[i].index, glyphs, glyphs_count, zero_context))
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return true;
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return false;
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}
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private:
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const hb_ot_map_t::lookup_map_t *lookups;
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unsigned int count;
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};
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struct indic_shape_plan_t
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{
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ASSERT_POD ();
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inline bool get_virama_glyph (hb_font_t *font, hb_codepoint_t *pglyph) const
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{
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hb_codepoint_t glyph = virama_glyph;
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if (unlikely (virama_glyph == (hb_codepoint_t) -1))
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{
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if (!config->virama || !font->get_glyph (config->virama, 0, &glyph))
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glyph = 0;
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/* Technically speaking, the spec says we should apply 'locl' to virama too.
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* Maybe one day... */
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/* Our get_glyph() function needs a font, so we can't get the virama glyph
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* during shape planning... Instead, overwrite it here. It's safe. Don't worry! */
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(const_cast<indic_shape_plan_t *> (this))->virama_glyph = glyph;
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}
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*pglyph = glyph;
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return glyph != 0;
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}
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const indic_config_t *config;
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bool is_old_spec;
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hb_codepoint_t virama_glyph;
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would_substitute_feature_t rphf;
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would_substitute_feature_t pref;
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would_substitute_feature_t blwf;
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would_substitute_feature_t pstf;
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hb_mask_t mask_array[INDIC_NUM_FEATURES];
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};
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static void *
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data_create_indic (const hb_ot_shape_plan_t *plan)
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{
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indic_shape_plan_t *indic_plan = (indic_shape_plan_t *) calloc (1, sizeof (indic_shape_plan_t));
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if (unlikely (!indic_plan))
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return NULL;
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indic_plan->config = &indic_configs[0];
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for (unsigned int i = 1; i < ARRAY_LENGTH (indic_configs); i++)
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if (plan->props.script == indic_configs[i].script) {
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indic_plan->config = &indic_configs[i];
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break;
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}
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indic_plan->is_old_spec = indic_plan->config->has_old_spec && ((plan->map.chosen_script[0] & 0x000000FF) != '2');
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indic_plan->virama_glyph = (hb_codepoint_t) -1;
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indic_plan->rphf.init (&plan->map, HB_TAG('r','p','h','f'));
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indic_plan->pref.init (&plan->map, HB_TAG('p','r','e','f'));
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indic_plan->blwf.init (&plan->map, HB_TAG('b','l','w','f'));
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indic_plan->pstf.init (&plan->map, HB_TAG('p','s','t','f'));
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for (unsigned int i = 0; i < ARRAY_LENGTH (indic_plan->mask_array); i++)
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indic_plan->mask_array[i] = indic_features[i].is_global ? 0 : plan->map.get_1_mask (indic_features[i].tag);
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return indic_plan;
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}
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static void
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data_destroy_indic (void *data)
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{
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free (data);
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}
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static indic_position_t
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consonant_position_from_face (const indic_shape_plan_t *indic_plan,
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hb_codepoint_t *glyphs, unsigned int glyphs_len,
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hb_face_t *face)
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{
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bool zero_context = indic_plan->is_old_spec ? false : true;
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if (indic_plan->pref.would_substitute (glyphs, glyphs_len, zero_context, face)) return POS_BELOW_C;
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if (indic_plan->blwf.would_substitute (glyphs, glyphs_len, zero_context, face)) return POS_BELOW_C;
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if (indic_plan->pstf.would_substitute (glyphs, glyphs_len, zero_context, face)) return POS_POST_C;
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return POS_BASE_C;
|
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}
|
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|
||
|
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enum syllable_type_t {
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consonant_syllable,
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vowel_syllable,
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standalone_cluster,
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broken_cluster,
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non_indic_cluster,
|
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};
|
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|
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#include "hb-ot-shape-complex-indic-machine.hh"
|
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|
||
|
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static void
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setup_masks_indic (const hb_ot_shape_plan_t *plan HB_UNUSED,
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hb_buffer_t *buffer,
|
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hb_font_t *font HB_UNUSED)
|
||
{
|
||
HB_BUFFER_ALLOCATE_VAR (buffer, indic_category);
|
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HB_BUFFER_ALLOCATE_VAR (buffer, indic_position);
|
||
|
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/* We cannot setup masks here. We save information about characters
|
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* and setup masks later on in a pause-callback. */
|
||
|
||
unsigned int count = buffer->len;
|
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for (unsigned int i = 0; i < count; i++)
|
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set_indic_properties (buffer->info[i]);
|
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}
|
||
|
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static void
|
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setup_syllables (const hb_ot_shape_plan_t *plan HB_UNUSED,
|
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hb_font_t *font HB_UNUSED,
|
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hb_buffer_t *buffer)
|
||
{
|
||
find_syllables (buffer);
|
||
}
|
||
|
||
static int
|
||
compare_indic_order (const hb_glyph_info_t *pa, const hb_glyph_info_t *pb)
|
||
{
|
||
int a = pa->indic_position();
|
||
int b = pb->indic_position();
|
||
|
||
return a < b ? -1 : a == b ? 0 : +1;
|
||
}
|
||
|
||
|
||
|
||
static void
|
||
update_consonant_positions (const hb_ot_shape_plan_t *plan,
|
||
hb_font_t *font,
|
||
hb_buffer_t *buffer)
|
||
{
|
||
const indic_shape_plan_t *indic_plan = (const indic_shape_plan_t *) plan->data;
|
||
|
||
unsigned int consonant_pos = indic_plan->is_old_spec ? 0 : 1;
|
||
hb_codepoint_t glyphs[2];
|
||
if (indic_plan->get_virama_glyph (font, &glyphs[1 - consonant_pos]))
|
||
{
|
||
hb_face_t *face = font->face;
|
||
unsigned int count = buffer->len;
|
||
for (unsigned int i = 0; i < count; i++)
|
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if (buffer->info[i].indic_position() == POS_BASE_C) {
|
||
glyphs[consonant_pos] = buffer->info[i].codepoint;
|
||
buffer->info[i].indic_position() = consonant_position_from_face (indic_plan, glyphs, 2, face);
|
||
}
|
||
}
|
||
}
|
||
|
||
|
||
/* 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 indic_shape_plan_t *indic_plan = (const indic_shape_plan_t *) plan->data;
|
||
hb_glyph_info_t *info = buffer->info;
|
||
|
||
|
||
/* 1. Find base consonant:
|
||
*
|
||
* The shaping engine finds the base consonant of the syllable, using the
|
||
* following algorithm: starting from the end of the syllable, move backwards
|
||
* until a consonant is found that does not have a below-base or post-base
|
||
* form (post-base forms have to follow below-base forms), or that is not a
|
||
* pre-base reordering Ra, or arrive at the first consonant. The consonant
|
||
* stopped at will be the base.
|
||
*
|
||
* o If the syllable starts with Ra + Halant (in a script that has Reph)
|
||
* and has more than one consonant, Ra is excluded from candidates for
|
||
* base consonants.
|
||
*/
|
||
|
||
unsigned int base = end;
|
||
bool has_reph = false;
|
||
|
||
{
|
||
/* -> If the syllable starts with Ra + Halant (in a script that has Reph)
|
||
* and has more than one consonant, Ra is excluded from candidates for
|
||
* base consonants. */
|
||
unsigned int limit = start;
|
||
if (indic_plan->mask_array[RPHF] &&
|
||
start + 3 <= end &&
|
||
(/* TODO Handle other Reph modes. */
|
||
(indic_plan->config->reph_mode == REPH_MODE_IMPLICIT && !is_joiner (info[start + 2])) ||
|
||
(indic_plan->config->reph_mode == REPH_MODE_EXPLICIT && info[start + 2].indic_category() == OT_ZWJ)
|
||
))
|
||
{
|
||
/* See if it matches the 'rphf' feature. */
|
||
hb_codepoint_t glyphs[2] = {info[start].codepoint, info[start + 1].codepoint};
|
||
if (indic_plan->rphf.would_substitute (glyphs, ARRAY_LENGTH (glyphs), true, face))
|
||
{
|
||
limit += 2;
|
||
while (limit < end && is_joiner (info[limit]))
|
||
limit++;
|
||
base = start;
|
||
has_reph = true;
|
||
}
|
||
};
|
||
|
||
switch (indic_plan->config->base_pos)
|
||
{
|
||
default:
|
||
assert (false);
|
||
/* fallthrough */
|
||
|
||
case BASE_POS_LAST:
|
||
{
|
||
/* -> starting from the end of the syllable, move backwards */
|
||
unsigned int i = end;
|
||
bool seen_below = false;
|
||
do {
|
||
i--;
|
||
/* -> until a consonant is found */
|
||
if (is_consonant (info[i]))
|
||
{
|
||
/* -> that does not have a below-base or post-base form
|
||
* (post-base forms have to follow below-base forms), */
|
||
if (info[i].indic_position() != POS_BELOW_C &&
|
||
(info[i].indic_position() != POS_POST_C || seen_below))
|
||
{
|
||
base = i;
|
||
break;
|
||
}
|
||
if (info[i].indic_position() == POS_BELOW_C)
|
||
seen_below = true;
|
||
|
||
/* -> or that is not a pre-base reordering Ra,
|
||
*
|
||
* IMPLEMENTATION NOTES:
|
||
*
|
||
* Our pre-base reordering Ra's are marked POS_BELOW, so will be skipped
|
||
* by the logic above already.
|
||
*/
|
||
|
||
/* -> or arrive at the first consonant. The consonant stopped at will
|
||
* be the base. */
|
||
base = i;
|
||
}
|
||
else
|
||
{
|
||
/* A ZWJ after a Halant stops the base search, and requests an explicit
|
||
* half form.
|
||
* A ZWJ before a Halant, requests a subjoined form instead, and hence
|
||
* search continues. This is particularly important for Bengali
|
||
* sequence Ra,H,Ya that should form Ya-Phalaa by subjoining Ya. */
|
||
if (start < i &&
|
||
info[i].indic_category() == OT_ZWJ &&
|
||
info[i - 1].indic_category() == OT_H)
|
||
break;
|
||
}
|
||
} while (i > limit);
|
||
}
|
||
break;
|
||
|
||
case BASE_POS_FIRST:
|
||
{
|
||
/* In scripts without half forms (eg. Khmer), the first consonant is always the base. */
|
||
|
||
if (!has_reph)
|
||
base = limit;
|
||
|
||
/* Find the last base consonant that is not blocked by ZWJ. If there is
|
||
* a ZWJ right before a base consonant, that would request a subjoined form. */
|
||
for (unsigned int i = limit; i < end; i++)
|
||
if (is_consonant (info[i]) && info[i].indic_position() == POS_BASE_C)
|
||
{
|
||
if (limit < i && info[i - 1].indic_category() == OT_ZWJ)
|
||
break;
|
||
else
|
||
base = i;
|
||
}
|
||
|
||
/* Mark all subsequent consonants as below. */
|
||
for (unsigned int i = base + 1; i < end; i++)
|
||
if (is_consonant (info[i]) && info[i].indic_position() == POS_BASE_C)
|
||
info[i].indic_position() = POS_BELOW_C;
|
||
}
|
||
break;
|
||
}
|
||
|
||
/* -> If the syllable starts with Ra + Halant (in a script that has Reph)
|
||
* and has more than one consonant, Ra is excluded from candidates for
|
||
* base consonants.
|
||
*
|
||
* Only do this for unforced Reph. (ie. not for Ra,H,ZWJ. */
|
||
if (has_reph && base == start && start + 2 == limit) {
|
||
/* Have no other consonant, so Reph is not formed and Ra becomes base. */
|
||
has_reph = false;
|
||
}
|
||
}
|
||
|
||
if (base < end)
|
||
info[base].indic_position() = POS_BASE_C;
|
||
|
||
|
||
/* 2. Decompose and reorder Matras:
|
||
*
|
||
* Each matra and any syllable modifier sign in the cluster are moved to the
|
||
* appropriate position relative to the consonant(s) in the cluster. The
|
||
* shaping engine decomposes two- or three-part matras into their constituent
|
||
* parts before any repositioning. Matra characters are classified by which
|
||
* consonant in a conjunct they have affinity for and are reordered to the
|
||
* following positions:
|
||
*
|
||
* o Before first half form in the syllable
|
||
* o After subjoined consonants
|
||
* o After post-form consonant
|
||
* o After main consonant (for above marks)
|
||
*
|
||
* IMPLEMENTATION NOTES:
|
||
*
|
||
* The normalize() routine has already decomposed matras for us, so we don't
|
||
* need to worry about that.
|
||
*/
|
||
|
||
|
||
/* 3. Reorder marks to canonical order:
|
||
*
|
||
* Adjacent nukta and halant or nukta and vedic sign are always repositioned
|
||
* if necessary, so that the nukta is first.
|
||
*
|
||
* IMPLEMENTATION NOTES:
|
||
*
|
||
* We don't need to do this: the normalize() routine already did this for us.
|
||
*/
|
||
|
||
|
||
/* Reorder characters */
|
||
|
||
for (unsigned int i = start; i < base; i++)
|
||
info[i].indic_position() = MIN (POS_PRE_C, (indic_position_t) info[i].indic_position());
|
||
|
||
if (base < end)
|
||
info[base].indic_position() = POS_BASE_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].indic_category() == OT_M) {
|
||
for (unsigned int j = i + 1; j < end; j++)
|
||
if (is_consonant (info[j])) {
|
||
info[j].indic_position() = POS_FINAL_C;
|
||
break;
|
||
}
|
||
break;
|
||
}
|
||
|
||
/* Handle beginning Ra */
|
||
if (has_reph)
|
||
info[start].indic_position() = POS_RA_TO_BECOME_REPH;
|
||
|
||
/* For old-style Indic script tags, move the first post-base Halant after
|
||
* last consonant. */
|
||
if (indic_plan->is_old_spec) {
|
||
for (unsigned int i = base + 1; i < end; i++)
|
||
if (info[i].indic_category() == OT_H) {
|
||
unsigned int j;
|
||
for (j = end - 1; j > i; j--)
|
||
if (is_consonant (info[j]))
|
||
break;
|
||
if (j > i) {
|
||
/* Move Halant to after last consonant. */
|
||
hb_glyph_info_t t = info[i];
|
||
memmove (&info[i], &info[i + 1], (j - i) * sizeof (info[0]));
|
||
info[j] = t;
|
||
}
|
||
break;
|
||
}
|
||
}
|
||
|
||
/* Attach misc marks to previous char to move with them. */
|
||
{
|
||
indic_position_t last_pos = POS_START;
|
||
for (unsigned int i = start; i < end; i++)
|
||
{
|
||
if ((FLAG (info[i].indic_category()) & (JOINER_FLAGS | FLAG (OT_N) | FLAG (OT_RS) | HALANT_OR_COENG_FLAGS)))
|
||
{
|
||
info[i].indic_position() = last_pos;
|
||
if (unlikely (info[i].indic_category() == OT_H &&
|
||
info[i].indic_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].indic_position() != POS_PRE_M) {
|
||
info[i].indic_position() = info[j - 1].indic_position();
|
||
break;
|
||
}
|
||
}
|
||
} else if (info[i].indic_position() != POS_SMVD) {
|
||
last_pos = (indic_position_t) info[i].indic_position();
|
||
}
|
||
}
|
||
}
|
||
/* Re-attach ZWJ, ZWNJ, and halant to next char, for after-base consonants. */
|
||
{
|
||
unsigned int last_halant = end;
|
||
for (unsigned int i = base + 1; i < end; i++)
|
||
if (is_halant_or_coeng (info[i]))
|
||
last_halant = i;
|
||
else if (is_consonant (info[i])) {
|
||
for (unsigned int j = last_halant; j < i; j++)
|
||
if (info[j].indic_position() != POS_SMVD)
|
||
info[j].indic_position() = info[i].indic_position();
|
||
}
|
||
}
|
||
|
||
{
|
||
/* Things are out-of-control for post base positions, they may shuffle
|
||
* around like crazy, so merge clusters. For pre-base stuff, we handle
|
||
* cluster issues in final reordering. */
|
||
buffer->merge_clusters (base, end);
|
||
/* Sit tight, rock 'n roll! */
|
||
hb_bubble_sort (info + start, end - start, compare_indic_order);
|
||
/* Find base again */
|
||
base = end;
|
||
for (unsigned int i = start; i < end; i++)
|
||
if (info[i].indic_position() == POS_BASE_C) {
|
||
base = i;
|
||
break;
|
||
}
|
||
}
|
||
|
||
/* Setup masks now */
|
||
|
||
{
|
||
hb_mask_t mask;
|
||
|
||
/* Reph */
|
||
for (unsigned int i = start; i < end && info[i].indic_position() == POS_RA_TO_BECOME_REPH; i++)
|
||
info[i].mask |= indic_plan->mask_array[RPHF];
|
||
|
||
/* Pre-base */
|
||
mask = indic_plan->mask_array[HALF];
|
||
for (unsigned int i = start; i < base; i++)
|
||
info[i].mask |= mask;
|
||
/* Base */
|
||
mask = 0;
|
||
if (base < end)
|
||
info[base].mask |= mask;
|
||
/* Post-base */
|
||
mask = indic_plan->mask_array[BLWF] | indic_plan->mask_array[ABVF] | indic_plan->mask_array[PSTF];
|
||
for (unsigned int i = base + 1; i < end; i++)
|
||
info[i].mask |= mask;
|
||
}
|
||
|
||
if (indic_plan->mask_array[PREF] && base + 2 < end)
|
||
{
|
||
/* Find a Halant,Ra sequence and mark it for pre-base reordering processing. */
|
||
for (unsigned int i = base + 1; i + 1 < end; i++) {
|
||
hb_codepoint_t glyphs[2] = {info[i].codepoint, info[i + 1].codepoint};
|
||
if (indic_plan->pref.would_substitute (glyphs, ARRAY_LENGTH (glyphs), true, face))
|
||
{
|
||
info[i++].mask |= indic_plan->mask_array[PREF];
|
||
info[i++].mask |= indic_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
|
||
*/
|
||
for (; i < end; i++)
|
||
info[i].mask |= indic_plan->mask_array[CFAR];
|
||
|
||
break;
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Apply ZWJ/ZWNJ effects */
|
||
for (unsigned int i = start + 1; i < end; i++)
|
||
if (is_joiner (info[i])) {
|
||
bool non_joiner = info[i].indic_category() == OT_ZWNJ;
|
||
unsigned int j = i;
|
||
|
||
do {
|
||
j--;
|
||
|
||
/* A ZWJ disables CJCT, however, it's mere presence is enough
|
||
* to disable ligation. No explicit action needed. */
|
||
|
||
/* A ZWNJ disables HALF. */
|
||
if (non_joiner)
|
||
info[j].mask &= ~indic_plan->mask_array[HALF];
|
||
|
||
} while (j > start && !is_consonant (info[j]));
|
||
}
|
||
}
|
||
|
||
|
||
static void
|
||
initial_reordering_vowel_syllable (const hb_ot_shape_plan_t *plan,
|
||
hb_face_t *face,
|
||
hb_buffer_t *buffer,
|
||
unsigned int start, unsigned int end)
|
||
{
|
||
/* We made the vowels look like consonants. So let's call the consonant logic! */
|
||
initial_reordering_consonant_syllable (plan, face, buffer, start, end);
|
||
}
|
||
|
||
static void
|
||
initial_reordering_standalone_cluster (const hb_ot_shape_plan_t *plan,
|
||
hb_face_t *face,
|
||
hb_buffer_t *buffer,
|
||
unsigned int start, unsigned int end)
|
||
{
|
||
/* We treat NBSP/dotted-circle as if they are consonants, so we should just chain.
|
||
* Only if not in compatibility mode that is... */
|
||
|
||
if (indic_options ().uniscribe_bug_compatible)
|
||
{
|
||
/* For dotted-circle, this is what Uniscribe does:
|
||
* If dotted-circle is the last glyph, it just does nothing.
|
||
* Ie. It doesn't form Reph. */
|
||
if (buffer->info[end - 1].indic_category() == OT_DOTTEDCIRCLE)
|
||
return;
|
||
}
|
||
|
||
initial_reordering_consonant_syllable (plan, face, buffer, start, end);
|
||
}
|
||
|
||
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 standalone_cluster. */
|
||
initial_reordering_standalone_cluster (plan, face, buffer, start, end);
|
||
}
|
||
|
||
static void
|
||
initial_reordering_non_indic_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 vowel_syllable: initial_reordering_vowel_syllable (plan, face, buffer, start, end); return;
|
||
case standalone_cluster: initial_reordering_standalone_cluster (plan, face, buffer, start, end); return;
|
||
case broken_cluster: initial_reordering_broken_cluster (plan, face, buffer, start, end); return;
|
||
case non_indic_cluster: initial_reordering_non_indic_cluster (plan, face, buffer, start, end); return;
|
||
}
|
||
}
|
||
|
||
static inline void
|
||
insert_dotted_circles (const hb_ot_shape_plan_t *plan,
|
||
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;
|
||
for (unsigned int i = 0; i < count; i++)
|
||
if ((buffer->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 (0x25CC, 0, &dottedcircle_glyph))
|
||
return;
|
||
|
||
hb_glyph_info_t dottedcircle = {0};
|
||
dottedcircle.codepoint = 0x25CC;
|
||
set_indic_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))
|
||
{
|
||
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);
|
||
last_syllable = syllable;
|
||
}
|
||
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)
|
||
{
|
||
update_consonant_positions (plan, font, 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_syllable (const hb_ot_shape_plan_t *plan,
|
||
hb_buffer_t *buffer,
|
||
unsigned int start, unsigned int end)
|
||
{
|
||
const indic_shape_plan_t *indic_plan = (const indic_shape_plan_t *) plan->data;
|
||
hb_glyph_info_t *info = buffer->info;
|
||
|
||
/* 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
|
||
* cluster.
|
||
*/
|
||
|
||
/* Find base again */
|
||
unsigned int base;
|
||
for (base = start; base < end; base++)
|
||
if (info[base].indic_position() >= POS_BASE_C) {
|
||
if (start < base && info[base].indic_position() > POS_BASE_C)
|
||
base--;
|
||
break;
|
||
}
|
||
|
||
|
||
/* 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;
|
||
|
||
/* Malayalam / Tamil do not have "half" forms or explicit virama forms.
|
||
* The glyphs formed by 'half' are Chillus or ligated explicit viramas.
|
||
* We want to position matra after them.
|
||
*/
|
||
if (buffer->props.script != HB_SCRIPT_MALAYALAM && buffer->props.script != HB_SCRIPT_TAMIL)
|
||
{
|
||
while (new_pos > start &&
|
||
!(is_one_of (info[new_pos], (FLAG (OT_M) | FLAG (OT_H) | 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_halant_or_coeng (info[new_pos]) &&
|
||
info[new_pos].indic_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].indic_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].indic_position () == POS_PRE_M)
|
||
{
|
||
unsigned int old_pos = i - 1;
|
||
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;
|
||
new_pos--;
|
||
}
|
||
buffer->merge_clusters (new_pos, MIN (end, base + 1));
|
||
} else {
|
||
for (unsigned int i = start; i < base; i++)
|
||
if (info[i].indic_position () == POS_PRE_M) {
|
||
buffer->merge_clusters (i, MIN (end, base + 1));
|
||
break;
|
||
}
|
||
}
|
||
}
|
||
|
||
|
||
/* o Reorder reph:
|
||
*
|
||
* Reph’s original position is always at the beginning of the syllable,
|
||
* (i.e. it is not reordered at the character reordering stage). However,
|
||
* it will be reordered according to the basic-forms shaping results.
|
||
* Possible positions for reph, depending on the script, are; after main,
|
||
* before post-base consonant forms, and after post-base consonant forms.
|
||
*/
|
||
|
||
/* If there's anything after the Ra that has the REPH pos, it ought to be halant.
|
||
* Which means that the font has failed to ligate the Reph. In which case, we
|
||
* shouldn't move. */
|
||
if (start + 1 < end &&
|
||
info[start].indic_position() == POS_RA_TO_BECOME_REPH &&
|
||
info[start + 1].indic_position() != POS_RA_TO_BECOME_REPH)
|
||
{
|
||
unsigned int new_reph_pos;
|
||
reph_position_t reph_pos = indic_plan->config->reph_pos;
|
||
|
||
/* XXX Figure out old behavior too */
|
||
|
||
/* 1. If reph should be positioned after post-base consonant forms,
|
||
* proceed to step 5.
|
||
*/
|
||
if (reph_pos == REPH_POS_AFTER_POST)
|
||
{
|
||
goto reph_step_5;
|
||
}
|
||
|
||
/* 2. If the reph repositioning class is not after post-base: target
|
||
* position is after the first explicit halant glyph between the
|
||
* first post-reph consonant and last main consonant. If ZWJ or ZWNJ
|
||
* are following this halant, position is moved after it. If such
|
||
* position is found, this is the target position. Otherwise,
|
||
* proceed to the next step.
|
||
*
|
||
* Note: in old-implementation fonts, where classifications were
|
||
* fixed in shaping engine, there was no case where reph position
|
||
* will be found on this step.
|
||
*/
|
||
{
|
||
new_reph_pos = start + 1;
|
||
while (new_reph_pos < base && !is_halant_or_coeng (info[new_reph_pos]))
|
||
new_reph_pos++;
|
||
|
||
if (new_reph_pos < base && is_halant_or_coeng (info[new_reph_pos])) {
|
||
/* ->If ZWJ or ZWNJ are following this halant, position is moved after it. */
|
||
if (new_reph_pos + 1 < base && is_joiner (info[new_reph_pos + 1]))
|
||
new_reph_pos++;
|
||
goto reph_move;
|
||
}
|
||
}
|
||
|
||
/* 3. If reph should be repositioned after the main consonant: find the
|
||
* first consonant not ligated with main, or find the first
|
||
* consonant that is not a potential pre-base reordering Ra.
|
||
*/
|
||
if (reph_pos == REPH_POS_AFTER_MAIN)
|
||
{
|
||
new_reph_pos = base;
|
||
/* XXX Skip potential pre-base reordering Ra. */
|
||
while (new_reph_pos + 1 < end && info[new_reph_pos + 1].indic_position() <= POS_AFTER_MAIN)
|
||
new_reph_pos++;
|
||
if (new_reph_pos < end)
|
||
goto reph_move;
|
||
}
|
||
|
||
/* 4. If reph should be positioned before post-base consonant, find
|
||
* first post-base classified consonant not ligated with main. If no
|
||
* consonant is found, the target position should be before the
|
||
* first matra, syllable modifier sign or vedic sign.
|
||
*/
|
||
/* This is our take on what step 4 is trying to say (and failing, BADLY). */
|
||
if (reph_pos == REPH_POS_AFTER_SUB)
|
||
{
|
||
new_reph_pos = base;
|
||
while (new_reph_pos < end &&
|
||
!( FLAG (info[new_reph_pos + 1].indic_position()) & (FLAG (POS_POST_C) | FLAG (POS_AFTER_POST) | FLAG (POS_SMVD))))
|
||
new_reph_pos++;
|
||
if (new_reph_pos < end)
|
||
goto reph_move;
|
||
}
|
||
|
||
/* 5. If no consonant is found in steps 3 or 4, move reph to a position
|
||
* immediately before the first post-base matra, syllable modifier
|
||
* sign or vedic sign that has a reordering class after the intended
|
||
* reph position. For example, if the reordering position for reph
|
||
* is post-main, it will skip above-base matras that also have a
|
||
* post-main position.
|
||
*/
|
||
reph_step_5:
|
||
{
|
||
/* Copied from step 2. */
|
||
new_reph_pos = start + 1;
|
||
while (new_reph_pos < base && !is_halant_or_coeng (info[new_reph_pos]))
|
||
new_reph_pos++;
|
||
|
||
if (new_reph_pos < base && is_halant_or_coeng (info[new_reph_pos])) {
|
||
/* ->If ZWJ or ZWNJ are following this halant, position is moved after it. */
|
||
if (new_reph_pos + 1 < base && is_joiner (info[new_reph_pos + 1]))
|
||
new_reph_pos++;
|
||
goto reph_move;
|
||
}
|
||
}
|
||
|
||
/* 6. Otherwise, reorder reph to the end of the syllable.
|
||
*/
|
||
{
|
||
new_reph_pos = end - 1;
|
||
while (new_reph_pos > start && info[new_reph_pos].indic_position() == POS_SMVD)
|
||
new_reph_pos--;
|
||
|
||
/*
|
||
* If the Reph is to be ending up after a Matra,Halant sequence,
|
||
* position it before that Halant so it can interact with the Matra.
|
||
* However, if it's a plain Consonant,Halant we shouldn't do that.
|
||
* Uniscribe doesn't do this.
|
||
* TEST: U+0930,U+094D,U+0915,U+094B,U+094D
|
||
*/
|
||
if (!indic_options ().uniscribe_bug_compatible &&
|
||
unlikely (is_halant_or_coeng (info[new_reph_pos]))) {
|
||
for (unsigned int i = base + 1; i < new_reph_pos; i++)
|
||
if (info[i].indic_category() == OT_M) {
|
||
/* Ok, got it. */
|
||
new_reph_pos--;
|
||
}
|
||
}
|
||
goto reph_move;
|
||
}
|
||
|
||
reph_move:
|
||
{
|
||
/* Yay, one big cluster! Merge before moving. */
|
||
buffer->merge_clusters (start, end);
|
||
|
||
/* Move */
|
||
hb_glyph_info_t reph = info[start];
|
||
memmove (&info[start], &info[start + 1], (new_reph_pos - start) * sizeof (info[0]));
|
||
info[new_reph_pos] = reph;
|
||
}
|
||
}
|
||
|
||
|
||
/* o Reorder pre-base reordering consonants:
|
||
*
|
||
* If a pre-base reordering consonant is found, reorder it according to
|
||
* the following rules:
|
||
*/
|
||
|
||
if (indic_plan->mask_array[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 & indic_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.)
|
||
*/
|
||
if (i + 1 == end || (info[i + 1].mask & indic_plan->mask_array[PREF]) == 0)
|
||
{
|
||
/*
|
||
* 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;
|
||
/* Malayalam / Tamil do not have "half" forms or explicit virama forms.
|
||
* The glyphs formed by 'half' are Chillus or ligated explicit viramas.
|
||
* We want to position matra after them.
|
||
*/
|
||
if (buffer->props.script != HB_SCRIPT_MALAYALAM && buffer->props.script != HB_SCRIPT_TAMIL)
|
||
{
|
||
while (new_pos > start &&
|
||
!(is_one_of (info[new_pos - 1], FLAG(OT_M) | HALANT_OR_COENG_FLAGS)))
|
||
new_pos--;
|
||
|
||
/* In Khmer coeng model, a V,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].indic_category() == OT_M)
|
||
{
|
||
unsigned int old_pos = i;
|
||
for (unsigned int i = base + 1; i < old_pos; i++)
|
||
if (info[i].indic_category() == OT_M)
|
||
{
|
||
new_pos--;
|
||
break;
|
||
}
|
||
}
|
||
}
|
||
|
||
if (new_pos > start && is_halant_or_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;
|
||
}
|
||
}
|
||
|
||
break;
|
||
}
|
||
}
|
||
|
||
|
||
/* Apply 'init' to the Left Matra if it's a word start. */
|
||
if (info[start].indic_position () == POS_PRE_M &&
|
||
(!start ||
|
||
!(FLAG (_hb_glyph_info_get_general_category (&info[start - 1])) &
|
||
FLAG_RANGE (HB_UNICODE_GENERAL_CATEGORY_FORMAT, HB_UNICODE_GENERAL_CATEGORY_NON_SPACING_MARK))))
|
||
info[start].mask |= indic_plan->mask_array[INIT];
|
||
|
||
|
||
/*
|
||
* Finish off the clusters and go home!
|
||
*/
|
||
if (indic_options ().uniscribe_bug_compatible)
|
||
{
|
||
/* Uniscribe merges the entire cluster.
|
||
* This means, half forms are submerged into the main consonants 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_buffer_t *buffer)
|
||
{
|
||
unsigned int count = buffer->len;
|
||
if (unlikely (!count)) return;
|
||
|
||
hb_glyph_info_t *info = buffer->info;
|
||
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()) {
|
||
final_reordering_syllable (plan, buffer, last, i);
|
||
last = i;
|
||
last_syllable = info[last].syllable();
|
||
}
|
||
final_reordering_syllable (plan, buffer, last, count);
|
||
|
||
/* Zero syllables now... */
|
||
for (unsigned int i = 0; i < count; i++)
|
||
info[i].syllable() = 0;
|
||
|
||
HB_BUFFER_DEALLOCATE_VAR (buffer, indic_category);
|
||
HB_BUFFER_DEALLOCATE_VAR (buffer, indic_position);
|
||
}
|
||
|
||
|
||
static hb_ot_shape_normalization_mode_t
|
||
normalization_preference_indic (const hb_segment_properties_t *props)
|
||
{
|
||
return HB_OT_SHAPE_NORMALIZATION_MODE_COMPOSED_DIACRITICS_NO_SHORT_CIRCUIT;
|
||
}
|
||
|
||
static hb_bool_t
|
||
decompose_indic (hb_unicode_funcs_t *unicode,
|
||
hb_codepoint_t ab,
|
||
hb_codepoint_t *a,
|
||
hb_codepoint_t *b)
|
||
{
|
||
switch (ab)
|
||
{
|
||
/* Don't decompose these. */
|
||
case 0x0931 : return false;
|
||
case 0x0B94 : return false;
|
||
|
||
|
||
/*
|
||
* Decompose split matras that don't have Unicode decompositions.
|
||
*/
|
||
|
||
case 0x0F77 : *a = 0x0FB2; *b= 0x0F81; return true;
|
||
case 0x0F79 : *a = 0x0FB3; *b= 0x0F81; return true;
|
||
case 0x17BE : *a = 0x17C1; *b= 0x17BE; return true;
|
||
case 0x17BF : *a = 0x17C1; *b= 0x17BF; return true;
|
||
case 0x17C0 : *a = 0x17C1; *b= 0x17C0; return true;
|
||
case 0x17C4 : *a = 0x17C1; *b= 0x17C4; return true;
|
||
case 0x17C5 : *a = 0x17C1; *b= 0x17C5; return true;
|
||
case 0x1925 : *a = 0x1920; *b= 0x1923; return true;
|
||
case 0x1926 : *a = 0x1920; *b= 0x1924; return true;
|
||
case 0x1B3C : *a = 0x1B42; *b= 0x1B3C; return true;
|
||
case 0x1112E : *a = 0x11127; *b= 0x11131; return true;
|
||
case 0x1112F : *a = 0x11127; *b= 0x11132; return true;
|
||
#if 0
|
||
/* This one has no decomposition in Unicode, but needs no decomposition either. */
|
||
/* case 0x0AC9 : return false; */
|
||
case 0x0B57 : *a = no decomp, -> RIGHT; return true;
|
||
case 0x1C29 : *a = no decomp, -> LEFT; return true;
|
||
case 0xA9C0 : *a = no decomp, -> RIGHT; return true;
|
||
case 0x111BF : *a = no decomp, -> ABOVE; return true;
|
||
#endif
|
||
}
|
||
|
||
if (indic_options ().uniscribe_bug_compatible)
|
||
switch (ab)
|
||
{
|
||
/* These Sinhala ones have Unicode decompositions, but Uniscribe
|
||
* decomposes them "Khmer-style". */
|
||
case 0x0DDA : *a = 0x0DD9; *b= 0x0DDA; return true;
|
||
case 0x0DDC : *a = 0x0DD9; *b= 0x0DDC; return true;
|
||
case 0x0DDD : *a = 0x0DD9; *b= 0x0DDD; return true;
|
||
case 0x0DDE : *a = 0x0DD9; *b= 0x0DDE; return true;
|
||
}
|
||
|
||
return unicode->decompose (ab, a, b);
|
||
}
|
||
|
||
static hb_bool_t
|
||
compose_indic (hb_unicode_funcs_t *unicode,
|
||
hb_codepoint_t a,
|
||
hb_codepoint_t b,
|
||
hb_codepoint_t *ab)
|
||
{
|
||
/* Avoid recomposing split matras. */
|
||
if (HB_UNICODE_GENERAL_CATEGORY_IS_MARK (unicode->general_category (a)))
|
||
return false;
|
||
|
||
/* Composition-exclusion exceptions that we want to recompose. */
|
||
if (a == 0x09AF && b == 0x09BC) { *ab = 0x09DF; return true; }
|
||
|
||
return unicode->compose (a, b, ab);
|
||
}
|
||
|
||
|
||
const hb_ot_complex_shaper_t _hb_ot_complex_shaper_indic =
|
||
{
|
||
"indic",
|
||
collect_features_indic,
|
||
override_features_indic,
|
||
data_create_indic,
|
||
data_destroy_indic,
|
||
NULL, /* preprocess_text */
|
||
normalization_preference_indic,
|
||
decompose_indic,
|
||
compose_indic,
|
||
setup_masks_indic,
|
||
false, /* zero_width_attached_marks */
|
||
false, /* fallback_position */
|
||
};
|