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Diffstat (limited to 'third_party/harfbuzz/src/harfbuzz-khmer.c')
| -rw-r--r-- | third_party/harfbuzz/src/harfbuzz-khmer.c | 667 |
1 files changed, 667 insertions, 0 deletions
diff --git a/third_party/harfbuzz/src/harfbuzz-khmer.c b/third_party/harfbuzz/src/harfbuzz-khmer.c new file mode 100644 index 0000000..958069e --- /dev/null +++ b/third_party/harfbuzz/src/harfbuzz-khmer.c @@ -0,0 +1,667 @@ +/* + * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies) + * + * This is part of HarfBuzz, an OpenType Layout engine 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. + */ + +#include "harfbuzz-shaper.h" +#include "harfbuzz-shaper-private.h" + +#include <assert.h> +#include <stdio.h> + +/* +// Vocabulary +// Base -> A consonant or an independent vowel in its full (not subscript) form. It is the +// center of the syllable, it can be surrounded by coeng (subscript) consonants, vowels, +// split vowels, signs... but there is only one base in a syllable, it has to be coded as +// the first character of the syllable. +// split vowel --> vowel that has two parts placed separately (e.g. Before and after the consonant). +// Khmer language has five of them. Khmer split vowels either have one part before the +// base and one after the base or they have a part before the base and a part above the base. +// The first part of all Khmer split vowels is the same character, identical to +// the glyph of Khmer dependent vowel SRA EI +// coeng --> modifier used in Khmer to construct coeng (subscript) consonants +// Differently than indian languages, the coeng modifies the consonant that follows it, +// not the one preceding it Each consonant has two forms, the base form and the subscript form +// the base form is the normal one (using the consonants code-point), the subscript form is +// displayed when the combination coeng + consonant is encountered. +// Consonant of type 1 -> A consonant which has subscript for that only occupies space under a base consonant +// Consonant of type 2.-> Its subscript form occupies space under and before the base (only one, RO) +// Consonant of Type 3 -> Its subscript form occupies space under and after the base (KHO, CHHO, THHO, BA, YO, SA) +// Consonant shifter -> Khmer has to series of consonants. The same dependent vowel has different sounds +// if it is attached to a consonant of the first series or a consonant of the second series +// Most consonants have an equivalent in the other series, but some of theme exist only in +// one series (for example SA). If we want to use the consonant SA with a vowel sound that +// can only be done with a vowel sound that corresponds to a vowel accompanying a consonant +// of the other series, then we need to use a consonant shifter: TRIISAP or MUSIKATOAN +// x17C9 y x17CA. TRIISAP changes a first series consonant to second series sound and +// MUSIKATOAN a second series consonant to have a first series vowel sound. +// Consonant shifter are both normally supercript marks, but, when they are followed by a +// superscript, they change shape and take the form of subscript dependent vowel SRA U. +// If they are in the same syllable as a coeng consonant, Unicode 3.0 says that they +// should be typed before the coeng. Unicode 4.0 breaks the standard and says that it should +// be placed after the coeng consonant. +// Dependent vowel -> In khmer dependent vowels can be placed above, below, before or after the base +// Each vowel has its own position. Only one vowel per syllable is allowed. +// Signs -> Khmer has above signs and post signs. Only one above sign and/or one post sign are +// Allowed in a syllable. +// +// +// order is important here! This order must be the same that is found in each horizontal +// line in the statetable for Khmer (see khmerStateTable) . +*/ +enum KhmerCharClassValues { + CC_RESERVED = 0, + CC_CONSONANT = 1, /* Consonant of type 1 or independent vowel */ + CC_CONSONANT2 = 2, /* Consonant of type 2 */ + CC_CONSONANT3 = 3, /* Consonant of type 3 */ + CC_ZERO_WIDTH_NJ_MARK = 4, /* Zero Width non joiner character (0x200C) */ + CC_CONSONANT_SHIFTER = 5, + CC_ROBAT = 6, /* Khmer special diacritic accent -treated differently in state table */ + CC_COENG = 7, /* Subscript consonant combining character */ + CC_DEPENDENT_VOWEL = 8, + CC_SIGN_ABOVE = 9, + CC_SIGN_AFTER = 10, + CC_ZERO_WIDTH_J_MARK = 11, /* Zero width joiner character */ + CC_COUNT = 12 /* This is the number of character classes */ +}; + + +enum KhmerCharClassFlags { + CF_CLASS_MASK = 0x0000FFFF, + + CF_CONSONANT = 0x01000000, /* flag to speed up comparing */ + CF_SPLIT_VOWEL = 0x02000000, /* flag for a split vowel -> the first part is added in front of the syllable */ + CF_DOTTED_CIRCLE = 0x04000000, /* add a dotted circle if a character with this flag is the first in a syllable */ + CF_COENG = 0x08000000, /* flag to speed up comparing */ + CF_SHIFTER = 0x10000000, /* flag to speed up comparing */ + CF_ABOVE_VOWEL = 0x20000000, /* flag to speed up comparing */ + + /* position flags */ + CF_POS_BEFORE = 0x00080000, + CF_POS_BELOW = 0x00040000, + CF_POS_ABOVE = 0x00020000, + CF_POS_AFTER = 0x00010000, + CF_POS_MASK = 0x000f0000 +}; + + +/* Characters that get referred to by name */ +enum KhmerChar { + C_SIGN_ZWNJ = 0x200C, + C_SIGN_ZWJ = 0x200D, + C_RO = 0x179A, + C_VOWEL_AA = 0x17B6, + C_SIGN_NIKAHIT = 0x17C6, + C_VOWEL_E = 0x17C1, + C_COENG = 0x17D2 +}; + + +/* +// simple classes, they are used in the statetable (in this file) to control the length of a syllable +// they are also used to know where a character should be placed (location in reference to the base character) +// and also to know if a character, when independently displayed, should be displayed with a dotted-circle to +// indicate error in syllable construction +*/ +enum { + _xx = CC_RESERVED, + _sa = CC_SIGN_ABOVE | CF_DOTTED_CIRCLE | CF_POS_ABOVE, + _sp = CC_SIGN_AFTER | CF_DOTTED_CIRCLE| CF_POS_AFTER, + _c1 = CC_CONSONANT | CF_CONSONANT, + _c2 = CC_CONSONANT2 | CF_CONSONANT, + _c3 = CC_CONSONANT3 | CF_CONSONANT, + _rb = CC_ROBAT | CF_POS_ABOVE | CF_DOTTED_CIRCLE, + _cs = CC_CONSONANT_SHIFTER | CF_DOTTED_CIRCLE | CF_SHIFTER, + _dl = CC_DEPENDENT_VOWEL | CF_POS_BEFORE | CF_DOTTED_CIRCLE, + _db = CC_DEPENDENT_VOWEL | CF_POS_BELOW | CF_DOTTED_CIRCLE, + _da = CC_DEPENDENT_VOWEL | CF_POS_ABOVE | CF_DOTTED_CIRCLE | CF_ABOVE_VOWEL, + _dr = CC_DEPENDENT_VOWEL | CF_POS_AFTER | CF_DOTTED_CIRCLE, + _co = CC_COENG | CF_COENG | CF_DOTTED_CIRCLE, + + /* split vowel */ + _va = _da | CF_SPLIT_VOWEL, + _vr = _dr | CF_SPLIT_VOWEL +}; + + +/* +// Character class: a character class value +// ORed with character class flags. +*/ +typedef unsigned long KhmerCharClass; + + +/* +// Character class tables +// _xx character does not combine into syllable, such as numbers, puntuation marks, non-Khmer signs... +// _sa Sign placed above the base +// _sp Sign placed after the base +// _c1 Consonant of type 1 or independent vowel (independent vowels behave as type 1 consonants) +// _c2 Consonant of type 2 (only RO) +// _c3 Consonant of type 3 +// _rb Khmer sign robat u17CC. combining mark for subscript consonants +// _cd Consonant-shifter +// _dl Dependent vowel placed before the base (left of the base) +// _db Dependent vowel placed below the base +// _da Dependent vowel placed above the base +// _dr Dependent vowel placed behind the base (right of the base) +// _co Khmer combining mark COENG u17D2, combines with the consonant or independent vowel following +// it to create a subscript consonant or independent vowel +// _va Khmer split vowel in which the first part is before the base and the second one above the base +// _vr Khmer split vowel in which the first part is before the base and the second one behind (right of) the base +*/ +static const KhmerCharClass khmerCharClasses[] = { + _c1, _c1, _c1, _c3, _c1, _c1, _c1, _c1, _c3, _c1, _c1, _c1, _c1, _c3, _c1, _c1, /* 1780 - 178F */ + _c1, _c1, _c1, _c1, _c3, _c1, _c1, _c1, _c1, _c3, _c2, _c1, _c1, _c1, _c3, _c3, /* 1790 - 179F */ + _c1, _c3, _c1, _c1, _c1, _c1, _c1, _c1, _c1, _c1, _c1, _c1, _c1, _c1, _c1, _c1, /* 17A0 - 17AF */ + _c1, _c1, _c1, _c1, _dr, _dr, _dr, _da, _da, _da, _da, _db, _db, _db, _va, _vr, /* 17B0 - 17BF */ + _vr, _dl, _dl, _dl, _vr, _vr, _sa, _sp, _sp, _cs, _cs, _sa, _rb, _sa, _sa, _sa, /* 17C0 - 17CF */ + _sa, _sa, _co, _sa, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _xx, _sa, _xx, _xx /* 17D0 - 17DF */ +}; + +/* this enum must reflect the range of khmerCharClasses */ +enum KhmerCharClassesRange { + KhmerFirstChar = 0x1780, + KhmerLastChar = 0x17df +}; + +/* +// Below we define how a character in the input string is either in the khmerCharClasses table +// (in which case we get its type back), a ZWJ or ZWNJ (two characters that may appear +// within the syllable, but are not in the table) we also get their type back, or an unknown object +// in which case we get _xx (CC_RESERVED) back +*/ +static KhmerCharClass getKhmerCharClass(HB_UChar16 uc) +{ + if (uc == C_SIGN_ZWJ) { + return CC_ZERO_WIDTH_J_MARK; + } + + if (uc == C_SIGN_ZWNJ) { + return CC_ZERO_WIDTH_NJ_MARK; + } + + if (uc < KhmerFirstChar || uc > KhmerLastChar) { + return CC_RESERVED; + } + + return khmerCharClasses[uc - KhmerFirstChar]; +} + + +/* +// The stateTable is used to calculate the end (the length) of a well +// formed Khmer Syllable. +// +// Each horizontal line is ordered exactly the same way as the values in KhmerClassTable +// CharClassValues. This coincidence of values allows the follow up of the table. +// +// Each line corresponds to a state, which does not necessarily need to be a type +// of component... for example, state 2 is a base, with is always a first character +// in the syllable, but the state could be produced a consonant of any type when +// it is the first character that is analysed (in ground state). +// +// Differentiating 3 types of consonants is necessary in order to +// forbid the use of certain combinations, such as having a second +// coeng after a coeng RO, +// The inexistent possibility of having a type 3 after another type 3 is permitted, +// eliminating it would very much complicate the table, and it does not create typing +// problems, as the case above. +// +// The table is quite complex, in order to limit the number of coeng consonants +// to 2 (by means of the table). +// +// There a peculiarity, as far as Unicode is concerned: +// - The consonant-shifter is considered in two possible different +// locations, the one considered in Unicode 3.0 and the one considered in +// Unicode 4.0. (there is a backwards compatibility problem in this standard). +// +// +// xx independent character, such as a number, punctuation sign or non-khmer char +// +// c1 Khmer consonant of type 1 or an independent vowel +// that is, a letter in which the subscript for is only under the +// base, not taking any space to the right or to the left +// +// c2 Khmer consonant of type 2, the coeng form takes space under +// and to the left of the base (only RO is of this type) +// +// c3 Khmer consonant of type 3. Its subscript form takes space under +// and to the right of the base. +// +// cs Khmer consonant shifter +// +// rb Khmer robat +// +// co coeng character (u17D2) +// +// dv dependent vowel (including split vowels, they are treated in the same way). +// even if dv is not defined above, the component that is really tested for is +// KhmerClassTable::CC_DEPENDENT_VOWEL, which is common to all dependent vowels +// +// zwj Zero Width joiner +// +// zwnj Zero width non joiner +// +// sa above sign +// +// sp post sign +// +// there are lines with equal content but for an easier understanding +// (and maybe change in the future) we did not join them +*/ +static const signed char khmerStateTable[][CC_COUNT] = +{ + /* xx c1 c2 c3 zwnj cs rb co dv sa sp zwj */ + { 1, 2, 2, 2, 1, 1, 1, 6, 1, 1, 1, 2}, /* 0 - ground state */ + {-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1}, /* 1 - exit state (or sign to the right of the syllable) */ + {-1, -1, -1, -1, 3, 4, 5, 6, 16, 17, 1, -1}, /* 2 - Base consonant */ + {-1, -1, -1, -1, -1, 4, -1, -1, 16, -1, -1, -1}, /* 3 - First ZWNJ before a register shifter It can only be followed by a shifter or a vowel */ + {-1, -1, -1, -1, 15, -1, -1, 6, 16, 17, 1, 14}, /* 4 - First register shifter */ + {-1, -1, -1, -1, -1, -1, -1, -1, 20, -1, 1, -1}, /* 5 - Robat */ + {-1, 7, 8, 9, -1, -1, -1, -1, -1, -1, -1, -1}, /* 6 - First Coeng */ + {-1, -1, -1, -1, 12, 13, -1, 10, 16, 17, 1, 14}, /* 7 - First consonant of type 1 after coeng */ + {-1, -1, -1, -1, 12, 13, -1, -1, 16, 17, 1, 14}, /* 8 - First consonant of type 2 after coeng */ + {-1, -1, -1, -1, 12, 13, -1, 10, 16, 17, 1, 14}, /* 9 - First consonant or type 3 after ceong */ + {-1, 11, 11, 11, -1, -1, -1, -1, -1, -1, -1, -1}, /* 10 - Second Coeng (no register shifter before) */ + {-1, -1, -1, -1, 15, -1, -1, -1, 16, 17, 1, 14}, /* 11 - Second coeng consonant (or ind. vowel) no register shifter before */ + {-1, -1, -1, -1, -1, 13, -1, -1, 16, -1, -1, -1}, /* 12 - Second ZWNJ before a register shifter */ + {-1, -1, -1, -1, 15, -1, -1, -1, 16, 17, 1, 14}, /* 13 - Second register shifter */ + {-1, -1, -1, -1, -1, -1, -1, -1, 16, -1, -1, -1}, /* 14 - ZWJ before vowel */ + {-1, -1, -1, -1, -1, -1, -1, -1, 16, -1, -1, -1}, /* 15 - ZWNJ before vowel */ + {-1, -1, -1, -1, -1, -1, -1, -1, -1, 17, 1, 18}, /* 16 - dependent vowel */ + {-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 1, 18}, /* 17 - sign above */ + {-1, -1, -1, -1, -1, -1, -1, 19, -1, -1, -1, -1}, /* 18 - ZWJ after vowel */ + {-1, 1, -1, 1, -1, -1, -1, -1, -1, -1, -1, -1}, /* 19 - Third coeng */ + {-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 1, -1}, /* 20 - dependent vowel after a Robat */ +}; + + +/* #define KHMER_DEBUG */ +#ifdef KHMER_DEBUG +#define KHDEBUG qDebug +#else +#define KHDEBUG if(0) printf +#endif + +/* +// Given an input string of characters and a location in which to start looking +// calculate, using the state table, which one is the last character of the syllable +// that starts in the starting position. +*/ +static int khmer_nextSyllableBoundary(const HB_UChar16 *s, int start, int end, HB_Bool *invalid) +{ + const HB_UChar16 *uc = s + start; + int state = 0; + int pos = start; + *invalid = FALSE; + + while (pos < end) { + KhmerCharClass charClass = getKhmerCharClass(*uc); + if (pos == start) { + *invalid = (charClass > 0) && ! (charClass & CF_CONSONANT); + } + state = khmerStateTable[state][charClass & CF_CLASS_MASK]; + + KHDEBUG("state[%d]=%d class=%8lx (uc=%4x)", pos - start, state, + charClass, *uc ); + + if (state < 0) { + break; + } + ++uc; + ++pos; + } + return pos; +} + +#ifndef NO_OPENTYPE +static const HB_OpenTypeFeature khmer_features[] = { + { HB_MAKE_TAG( 'p', 'r', 'e', 'f' ), PreFormProperty }, + { HB_MAKE_TAG( 'b', 'l', 'w', 'f' ), BelowFormProperty }, + { HB_MAKE_TAG( 'a', 'b', 'v', 'f' ), AboveFormProperty }, + { HB_MAKE_TAG( 'p', 's', 't', 'f' ), PostFormProperty }, + { HB_MAKE_TAG( 'p', 'r', 'e', 's' ), PreSubstProperty }, + { HB_MAKE_TAG( 'b', 'l', 'w', 's' ), BelowSubstProperty }, + { HB_MAKE_TAG( 'a', 'b', 'v', 's' ), AboveSubstProperty }, + { HB_MAKE_TAG( 'p', 's', 't', 's' ), PostSubstProperty }, + { HB_MAKE_TAG( 'c', 'l', 'i', 'g' ), CligProperty }, + { 0, 0 } +}; +#endif + + +static HB_Bool khmer_shape_syllable(HB_Bool openType, HB_ShaperItem *item) +{ +/* KHDEBUG("syllable from %d len %d, str='%s'", item->from, item->length, + item->string->mid(item->from, item->length).toUtf8().data()); */ + + int len = 0; + int syllableEnd = item->item.pos + item->item.length; + unsigned short reordered[16]; + unsigned char properties[16]; + enum { + AboveForm = 0x01, + PreForm = 0x02, + PostForm = 0x04, + BelowForm = 0x08 + }; +#ifndef NO_OPENTYPE + const int availableGlyphs = item->num_glyphs; +#endif + int coengRo; + int i; + + /* according to the specs this is the max length one can get + ### the real value should be smaller */ + assert(item->item.length < 13); + + memset(properties, 0, 16*sizeof(unsigned char)); + +#ifdef KHMER_DEBUG + qDebug("original:"); + for (int i = from; i < syllableEnd; i++) { + qDebug(" %d: %4x", i, string[i]); + } +#endif + + /* + // write a pre vowel or the pre part of a split vowel first + // and look out for coeng + ro. RO is the only vowel of type 2, and + // therefore the only one that requires saving space before the base. + */ + coengRo = -1; /* There is no Coeng Ro, if found this value will change */ + for (i = item->item.pos; i < syllableEnd; i += 1) { + KhmerCharClass charClass = getKhmerCharClass(item->string[i]); + + /* if a split vowel, write the pre part. In Khmer the pre part + is the same for all split vowels, same glyph as pre vowel C_VOWEL_E */ + if (charClass & CF_SPLIT_VOWEL) { + reordered[len] = C_VOWEL_E; + properties[len] = PreForm; + ++len; + break; /* there can be only one vowel */ + } + /* if a vowel with pos before write it out */ + if (charClass & CF_POS_BEFORE) { + reordered[len] = item->string[i]; + properties[len] = PreForm; + ++len; + break; /* there can be only one vowel */ + } + /* look for coeng + ro and remember position + works because coeng + ro is always in front of a vowel (if there is a vowel) + and because CC_CONSONANT2 is enough to identify it, as it is the only consonant + with this flag */ + if ( (charClass & CF_COENG) && (i + 1 < syllableEnd) && + ( (getKhmerCharClass(item->string[i+1]) & CF_CLASS_MASK) == CC_CONSONANT2) ) { + coengRo = i; + } + } + + /* write coeng + ro if found */ + if (coengRo > -1) { + reordered[len] = C_COENG; + properties[len] = PreForm; + ++len; + reordered[len] = C_RO; + properties[len] = PreForm; + ++len; + } + + /* + shall we add a dotted circle? + If in the position in which the base should be (first char in the string) there is + a character that has the Dotted circle flag (a character that cannot be a base) + then write a dotted circle */ + if (getKhmerCharClass(item->string[item->item.pos]) & CF_DOTTED_CIRCLE) { + reordered[len] = C_DOTTED_CIRCLE; + ++len; + } + + /* copy what is left to the output, skipping before vowels and + coeng Ro if they are present */ + for (i = item->item.pos; i < syllableEnd; i += 1) { + HB_UChar16 uc = item->string[i]; + KhmerCharClass charClass = getKhmerCharClass(uc); + + /* skip a before vowel, it was already processed */ + if (charClass & CF_POS_BEFORE) { + continue; + } + + /* skip coeng + ro, it was already processed */ + if (i == coengRo) { + i += 1; + continue; + } + + switch (charClass & CF_POS_MASK) + { + case CF_POS_ABOVE : + reordered[len] = uc; + properties[len] = AboveForm; + ++len; + break; + + case CF_POS_AFTER : + reordered[len] = uc; + properties[len] = PostForm; + ++len; + break; + + case CF_POS_BELOW : + reordered[len] = uc; + properties[len] = BelowForm; + ++len; + break; + + default: + /* assign the correct flags to a coeng consonant + Consonants of type 3 are taged as Post forms and those type 1 as below forms */ + if ( (charClass & CF_COENG) && i + 1 < syllableEnd ) { + unsigned char property = (getKhmerCharClass(item->string[i+1]) & CF_CLASS_MASK) == CC_CONSONANT3 ? + PostForm : BelowForm; + reordered[len] = uc; + properties[len] = property; + ++len; + i += 1; + reordered[len] = item->string[i]; + properties[len] = property; + ++len; + break; + } + + /* if a shifter is followed by an above vowel change the shifter to below form, + an above vowel can have two possible positions i + 1 or i + 3 + (position i+1 corresponds to unicode 3, position i+3 to Unicode 4) + and there is an extra rule for C_VOWEL_AA + C_SIGN_NIKAHIT also for two + different positions, right after the shifter or after a vowel (Unicode 4) */ + if ( (charClass & CF_SHIFTER) && (i + 1 < syllableEnd) ) { + if (getKhmerCharClass(item->string[i+1]) & CF_ABOVE_VOWEL ) { + reordered[len] = uc; + properties[len] = BelowForm; + ++len; + break; + } + if (i + 2 < syllableEnd && + (item->string[i+1] == C_VOWEL_AA) && + (item->string[i+2] == C_SIGN_NIKAHIT) ) + { + reordered[len] = uc; + properties[len] = BelowForm; + ++len; + break; + } + if (i + 3 < syllableEnd && (getKhmerCharClass(item->string[i+3]) & CF_ABOVE_VOWEL) ) { + reordered[len] = uc; + properties[len] = BelowForm; + ++len; + break; + } + if (i + 4 < syllableEnd && + (item->string[i+3] == C_VOWEL_AA) && + (item->string[i+4] == C_SIGN_NIKAHIT) ) + { + reordered[len] = uc; + properties[len] = BelowForm; + ++len; + break; + } + } + + /* default - any other characters */ + reordered[len] = uc; + ++len; + break; + } /* switch */ + } /* for */ + + if (!item->font->klass->convertStringToGlyphIndices(item->font, + reordered, len, + item->glyphs, &item->num_glyphs, + item->item.bidiLevel % 2)) + return FALSE; + + + KHDEBUG("after shaping: len=%d", len); + for (i = 0; i < len; i++) { + item->attributes[i].mark = FALSE; + item->attributes[i].clusterStart = FALSE; + item->attributes[i].justification = 0; + item->attributes[i].zeroWidth = FALSE; + KHDEBUG(" %d: %4x property=%x", i, reordered[i], properties[i]); + } + + /* now we have the syllable in the right order, and can start running it through open type. */ + +#ifndef NO_OPENTYPE + if (openType) { + hb_uint32 where[16]; + for (i = 0; i < len; ++i) { + where[i] = ~(PreSubstProperty + | BelowSubstProperty + | AboveSubstProperty + | PostSubstProperty + | CligProperty + | PositioningProperties); + if (properties[i] == PreForm) + where[i] &= ~PreFormProperty; + else if (properties[i] == BelowForm) + where[i] &= ~BelowFormProperty; + else if (properties[i] == AboveForm) + where[i] &= ~AboveFormProperty; + else if (properties[i] == PostForm) + where[i] &= ~PostFormProperty; + } + + HB_OpenTypeShape(item, where); + if (!HB_OpenTypePosition(item, availableGlyphs, /*doLogClusters*/FALSE)) + return FALSE; + } else +#endif + { + KHDEBUG("Not using openType"); + HB_HeuristicPosition(item); + } + + item->attributes[0].clusterStart = TRUE; + return TRUE; +} + +HB_Bool HB_KhmerShape(HB_ShaperItem *item) +{ + HB_Bool openType = FALSE; + unsigned short *logClusters = item->log_clusters; + int i; + + HB_ShaperItem syllable = *item; + int first_glyph = 0; + + int sstart = item->item.pos; + int end = sstart + item->item.length; + + assert(item->item.script == HB_Script_Khmer); + +#ifndef NO_OPENTYPE + openType = HB_SelectScript(item, khmer_features); +#endif + + KHDEBUG("khmer_shape: from %d length %d", item->item.pos, item->item.length); + while (sstart < end) { + HB_Bool invalid; + int send = khmer_nextSyllableBoundary(item->string, sstart, end, &invalid); + KHDEBUG("syllable from %d, length %d, invalid=%s", sstart, send-sstart, + invalid ? "TRUE" : "FALSE"); + syllable.item.pos = sstart; + syllable.item.length = send-sstart; + syllable.glyphs = item->glyphs + first_glyph; + syllable.attributes = item->attributes + first_glyph; + syllable.offsets = item->offsets + first_glyph; + syllable.advances = item->advances + first_glyph; + syllable.num_glyphs = item->num_glyphs - first_glyph; + if (!khmer_shape_syllable(openType, &syllable)) { + KHDEBUG("syllable shaping failed, syllable requests %d glyphs", syllable.num_glyphs); + item->num_glyphs += syllable.num_glyphs; + return FALSE; + } + /* fix logcluster array */ + KHDEBUG("syllable:"); + for (i = first_glyph; i < first_glyph + (int)syllable.num_glyphs; ++i) + KHDEBUG(" %d -> glyph %x", i, item->glyphs[i]); + KHDEBUG(" logclusters:"); + for (i = sstart; i < send; ++i) { + KHDEBUG(" %d -> glyph %d", i, first_glyph); + logClusters[i-item->item.pos] = first_glyph; + } + sstart = send; + first_glyph += syllable.num_glyphs; + } + item->num_glyphs = first_glyph; + return TRUE; +} + +void HB_KhmerAttributes(HB_Script script, const HB_UChar16 *text, hb_uint32 from, hb_uint32 len, HB_CharAttributes *attributes) +{ + int end = from + len; + const HB_UChar16 *uc = text + from; + hb_uint32 i = 0; + HB_UNUSED(script); + attributes += from; + while ( i < len ) { + HB_Bool invalid; + hb_uint32 boundary = khmer_nextSyllableBoundary( text, from+i, end, &invalid ) - from; + + attributes[i].charStop = TRUE; + + if ( boundary > len-1 ) boundary = len; + i++; + while ( i < boundary ) { + attributes[i].charStop = FALSE; + ++uc; + ++i; + } + assert( i == boundary ); + } +} + |