+++ /dev/null
-/*
- *
- * (C) Copyright IBM Corp. 1998-2007 - All Rights Reserved
- *
- * This file is a modification of the ICU file IndicReordering.cpp
- * by Jens Herden and Javier Sola for Khmer language
- *
- */
-
-#include "LETypes.h"
-#include "OpenTypeTables.h"
-#include "KhmerReordering.h"
-#include "LEGlyphStorage.h"
-
-
-U_NAMESPACE_BEGIN
-
-// Characters that get refered to by name...
-enum
-{
- C_SIGN_ZWNJ = 0x200C,
- C_SIGN_ZWJ = 0x200D,
- C_DOTTED_CIRCLE = 0x25CC,
- C_RO = 0x179A,
- C_VOWEL_AA = 0x17B6,
- C_SIGN_NIKAHIT = 0x17C6,
- C_VOWEL_E = 0x17C1,
- C_COENG = 0x17D2
-};
-
-
-enum
-{
- // 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 independtly displayed, should be displayed with a dotted-circle to
- // indicate error in syllable construction
- _xx = KhmerClassTable::CC_RESERVED,
- _sa = KhmerClassTable::CC_SIGN_ABOVE | KhmerClassTable::CF_DOTTED_CIRCLE | KhmerClassTable::CF_POS_ABOVE,
- _sp = KhmerClassTable::CC_SIGN_AFTER | KhmerClassTable::CF_DOTTED_CIRCLE| KhmerClassTable::CF_POS_AFTER,
- _c1 = KhmerClassTable::CC_CONSONANT | KhmerClassTable::CF_CONSONANT,
- _c2 = KhmerClassTable::CC_CONSONANT2 | KhmerClassTable::CF_CONSONANT,
- _c3 = KhmerClassTable::CC_CONSONANT3 | KhmerClassTable::CF_CONSONANT,
- _rb = KhmerClassTable::CC_ROBAT | KhmerClassTable::CF_POS_ABOVE | KhmerClassTable::CF_DOTTED_CIRCLE,
- _cs = KhmerClassTable::CC_CONSONANT_SHIFTER | KhmerClassTable::CF_DOTTED_CIRCLE | KhmerClassTable::CF_SHIFTER,
- _dl = KhmerClassTable::CC_DEPENDENT_VOWEL | KhmerClassTable::CF_POS_BEFORE | KhmerClassTable::CF_DOTTED_CIRCLE,
- _db = KhmerClassTable::CC_DEPENDENT_VOWEL | KhmerClassTable::CF_POS_BELOW | KhmerClassTable::CF_DOTTED_CIRCLE,
- _da = KhmerClassTable::CC_DEPENDENT_VOWEL | KhmerClassTable::CF_POS_ABOVE | KhmerClassTable::CF_DOTTED_CIRCLE | KhmerClassTable::CF_ABOVE_VOWEL,
- _dr = KhmerClassTable::CC_DEPENDENT_VOWEL | KhmerClassTable::CF_POS_AFTER | KhmerClassTable::CF_DOTTED_CIRCLE,
- _co = KhmerClassTable::CC_COENG | KhmerClassTable::CF_COENG | KhmerClassTable::CF_DOTTED_CIRCLE,
-
- // split vowel
- _va = _da | KhmerClassTable::CF_SPLIT_VOWEL,
- _vr = _dr | KhmerClassTable::CF_SPLIT_VOWEL
-};
-
-
-// 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 wich the first part is before the base and the second one above the base
-// _vr Khmer split vowel in wich the first part is before the base and the second one behind (right of) the base
-
-static const KhmerClassTable::CharClass 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
-};
-
-
-//
-// Khmer Class Tables
-//
-
-//
-// The range of characters defined in the above table is defined here. FOr Khmer 1780 to 17DF
-// Even if the Khmer range is bigger, all other characters are not combinable, and therefore treated
-// as _xx
-static const KhmerClassTable khmerClassTable = {0x1780, 0x17df, khmerCharClasses};
-
-
-// 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
-KhmerClassTable::CharClass KhmerClassTable::getCharClass(LEUnicode ch) const
-{
-
- if (ch == C_SIGN_ZWJ) {
- return CC_ZERO_WIDTH_J_MARK;
- }
-
- if (ch == C_SIGN_ZWNJ) {
- return CC_ZERO_WIDTH_NJ_MARK;
- }
-
- if (ch < firstChar || ch > lastChar) {
- return CC_RESERVED;
- }
-
- return classTable[ch - firstChar];
-}
-
-const KhmerClassTable *KhmerClassTable::getKhmerClassTable()
-{
- return &khmerClassTable;
-}
-
-
-
-class KhmerReorderingOutput : public UMemory {
-private:
- le_int32 fSyllableCount;
- le_int32 fOutIndex;
- LEUnicode *fOutChars;
-
- LEGlyphStorage &fGlyphStorage;
-
-
-public:
- KhmerReorderingOutput(LEUnicode *outChars, LEGlyphStorage &glyphStorage)
- : fSyllableCount(0), fOutIndex(0), fOutChars(outChars), fGlyphStorage(glyphStorage)
- {
- // nothing else to do...
- }
-
- ~KhmerReorderingOutput()
- {
- // nothing to do here...
- }
-
- void reset()
- {
- fSyllableCount += 1;
- }
-
- void writeChar(LEUnicode ch, le_uint32 charIndex, FeatureMask charFeatures)
- {
- LEErrorCode success = LE_NO_ERROR;
-
- fOutChars[fOutIndex] = ch;
-
- fGlyphStorage.setCharIndex(fOutIndex, charIndex, success);
- fGlyphStorage.setAuxData(fOutIndex, charFeatures | (fSyllableCount & LE_GLYPH_GROUP_MASK), success);
-
- fOutIndex += 1;
- }
-
- le_int32 getOutputIndex()
- {
- return fOutIndex;
- }
-};
-
-
-#define blwfFeatureTag LE_BLWF_FEATURE_TAG
-#define pstfFeatureTag LE_PSTF_FEATURE_TAG
-#define presFeatureTag LE_PRES_FEATURE_TAG
-#define blwsFeatureTag LE_BLWS_FEATURE_TAG
-#define abvsFeatureTag LE_ABVS_FEATURE_TAG
-#define pstsFeatureTag LE_PSTS_FEATURE_TAG
-
-#define blwmFeatureTag LE_BLWM_FEATURE_TAG
-#define abvmFeatureTag LE_ABVM_FEATURE_TAG
-#define distFeatureTag LE_DIST_FEATURE_TAG
-
-#define prefFeatureTag LE_PREF_FEATURE_TAG
-#define abvfFeatureTag LE_ABVF_FEATURE_TAG
-#define cligFeatureTag LE_CLIG_FEATURE_TAG
-#define mkmkFeatureTag LE_MKMK_FEATURE_TAG
-
-#define prefFeatureMask 0x80000000UL
-#define blwfFeatureMask 0x40000000UL
-#define abvfFeatureMask 0x20000000UL
-#define pstfFeatureMask 0x10000000UL
-#define presFeatureMask 0x08000000UL
-#define blwsFeatureMask 0x04000000UL
-#define abvsFeatureMask 0x02000000UL
-#define pstsFeatureMask 0x01000000UL
-#define cligFeatureMask 0x00800000UL
-#define distFeatureMask 0x00400000UL
-#define blwmFeatureMask 0x00200000UL
-#define abvmFeatureMask 0x00100000UL
-#define mkmkFeatureMask 0x00080000UL
-
-#define tagPref (prefFeatureMask | presFeatureMask | cligFeatureMask | distFeatureMask)
-#define tagAbvf (abvfFeatureMask | abvsFeatureMask | cligFeatureMask | distFeatureMask | abvmFeatureMask | mkmkFeatureMask)
-#define tagPstf (blwfFeatureMask | blwsFeatureMask | prefFeatureMask | presFeatureMask | pstfFeatureMask | pstsFeatureMask | cligFeatureMask | distFeatureMask | blwmFeatureMask)
-#define tagBlwf (blwfFeatureMask | blwsFeatureMask | cligFeatureMask | distFeatureMask | blwmFeatureMask | mkmkFeatureMask)
-#define tagDefault (prefFeatureMask | blwfFeatureMask | presFeatureMask | blwsFeatureMask | cligFeatureMask | distFeatureMask | abvmFeatureMask | blwmFeatureMask | mkmkFeatureMask)
-
-
-
-// These are in the order in which the features need to be applied
-// for correct processing
-static const FeatureMap featureMap[] =
-{
- // Shaping features
- {prefFeatureTag, prefFeatureMask},
- {blwfFeatureTag, blwfFeatureMask},
- {abvfFeatureTag, abvfFeatureMask},
- {pstfFeatureTag, pstfFeatureMask},
- {presFeatureTag, presFeatureMask},
- {blwsFeatureTag, blwsFeatureMask},
- {abvsFeatureTag, abvsFeatureMask},
- {pstsFeatureTag, pstsFeatureMask},
- {cligFeatureTag, cligFeatureMask},
-
- // Positioning features
- {distFeatureTag, distFeatureMask},
- {blwmFeatureTag, blwmFeatureMask},
- {abvmFeatureTag, abvmFeatureMask},
- {mkmkFeatureTag, mkmkFeatureMask},
-};
-
-static const le_int32 featureMapCount = LE_ARRAY_SIZE(featureMap);
-
-// 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 in KhmerReordering.h 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 le_int8 khmerStateTable[][KhmerClassTable::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
-
-};
-
-
-const FeatureMap *KhmerReordering::getFeatureMap(le_int32 &count)
-{
- count = featureMapCount;
-
- return featureMap;
-}
-
-
-// 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.
-le_int32 KhmerReordering::findSyllable(const KhmerClassTable *classTable, const LEUnicode *chars, le_int32 prev, le_int32 charCount)
-{
- le_int32 cursor = prev;
- le_int8 state = 0;
-
- while (cursor < charCount) {
- KhmerClassTable::CharClass charClass = (classTable->getCharClass(chars[cursor]) & KhmerClassTable::CF_CLASS_MASK);
-
- state = khmerStateTable[state][charClass];
-
- if (state < 0) {
- break;
- }
-
- cursor += 1;
- }
-
- return cursor;
-}
-
-
-// This is the real reordering function as applied to the Khmer language
-
-le_int32 KhmerReordering::reorder(const LEUnicode *chars, le_int32 charCount, le_int32 /*scriptCode*/,
- LEUnicode *outChars, LEGlyphStorage &glyphStorage)
-{
- const KhmerClassTable *classTable = KhmerClassTable::getKhmerClassTable();
-
- KhmerReorderingOutput output(outChars, glyphStorage);
- KhmerClassTable::CharClass charClass;
- le_int32 i, prev = 0, coengRo;
-
-
- // This loop only exits when we reach the end of a run, which may contain
- // several syllables.
- while (prev < charCount) {
- le_int32 syllable = findSyllable(classTable, chars, prev, charCount);
-
- output.reset();
-
- // 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 = prev; i < syllable; i += 1) {
- charClass = classTable->getCharClass(chars[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 & KhmerClassTable::CF_SPLIT_VOWEL) {
- output.writeChar(C_VOWEL_E, i, tagPref);
- break; // there can be only one vowel
- }
-
- // if a vowel with pos before write it out
- if (charClass & KhmerClassTable::CF_POS_BEFORE) {
- output.writeChar(chars[i], i, tagPref);
- 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 & KhmerClassTable::CF_COENG) && (i + 1 < syllable) &&
- ( (classTable->getCharClass(chars[i + 1]) & KhmerClassTable::CF_CLASS_MASK) == KhmerClassTable::CC_CONSONANT2) )
- {
- coengRo = i;
- }
- }
-
- // write coeng + ro if found
- if (coengRo > -1) {
- output.writeChar(C_COENG, coengRo, tagPref);
- output.writeChar(C_RO, coengRo + 1, tagPref);
- }
-
- // 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 (classTable->getCharClass(chars[prev]) & KhmerClassTable::CF_DOTTED_CIRCLE) {
- output.writeChar(C_DOTTED_CIRCLE, prev, tagDefault);
- }
-
- // copy what is left to the output, skipping before vowels and coeng Ro if they are present
- for (i = prev; i < syllable; i += 1) {
- charClass = classTable->getCharClass(chars[i]);
-
- // skip a before vowel, it was already processed
- if (charClass & KhmerClassTable::CF_POS_BEFORE) {
- continue;
- }
-
- // skip coeng + ro, it was already processed
- if (i == coengRo) {
- i += 1;
- continue;
- }
-
- switch (charClass & KhmerClassTable::CF_POS_MASK) {
- case KhmerClassTable::CF_POS_ABOVE :
- output.writeChar(chars[i], i, tagAbvf);
- break;
-
- case KhmerClassTable::CF_POS_AFTER :
- output.writeChar(chars[i], i, tagPstf);
- break;
-
- case KhmerClassTable::CF_POS_BELOW :
- output.writeChar(chars[i], i, tagBlwf);
- 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 & KhmerClassTable::CF_COENG) && i + 1 < syllable ) {
- if ( (classTable->getCharClass(chars[i + 1]) & KhmerClassTable::CF_CLASS_MASK)
- == KhmerClassTable::CC_CONSONANT3) {
- output.writeChar(chars[i], i, tagPstf);
- i += 1;
- output.writeChar(chars[i], i, tagPstf);
- }
- else {
- output.writeChar(chars[i], i, tagBlwf);
- i += 1;
- output.writeChar(chars[i], i, tagBlwf);
- }
- 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 & KhmerClassTable::CF_SHIFTER) && (i + 1 < syllable) ) {
- if ((classTable->getCharClass(chars[i + 1]) & KhmerClassTable::CF_ABOVE_VOWEL)
- || (i + 2 < syllable
- && ( (classTable->getCharClass(chars[i + 1]) & KhmerClassTable::CF_CLASS_MASK) == C_VOWEL_AA)
- && ( (classTable->getCharClass(chars[i + 2]) & KhmerClassTable::CF_CLASS_MASK) == C_SIGN_NIKAHIT))
- || (i + 3 < syllable && (classTable->getCharClass(chars[i + 3]) & KhmerClassTable::CF_ABOVE_VOWEL))
- || (i + 4 < syllable
- && ( (classTable->getCharClass(chars[i + 3]) & KhmerClassTable::CF_CLASS_MASK) == C_VOWEL_AA)
- && ( (classTable->getCharClass(chars[i + 4]) & KhmerClassTable::CF_CLASS_MASK) == C_SIGN_NIKAHIT) ) )
- {
- output.writeChar(chars[i], i, tagBlwf);
- break;
- }
-
- }
- // default - any other characters
- output.writeChar(chars[i], i, tagDefault);
- break;
- } // switch
- } // for
-
- prev = syllable; // move the pointer to the start of next syllable
- }
-
- return output.getOutputIndex();
-}
-
-
-U_NAMESPACE_END
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