scuffed-code/icu4c/source/layout/IndicReordering.cpp

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/*
* %W% %E%
*
* (C) Copyright IBM Corp. 1998, 1999, 2000 - All Rights Reserved
*
*/
#include "LETypes.h"
#include "OpenTypeTables.h"
#include "OpenTypeUtilities.h"
#include "IndicReordering.h"
U_NAMESPACE_BEGIN
class ReorderingOutput
{
private:
le_int32 fOutIndex;
LEUnicode *fOutChars;
le_int32 *fCharIndices;
const LETag **fCharTags;
LEUnicode fMpre;
LEUnicode fMbelow;
LEUnicode fMabove;
LEUnicode fMpost;
LEUnicode fLengthMark;
le_int32 fMatraIndex;
const LETag *fMatraTags;
void saveMatra(LEUnicode matra, IndicClassTable::CharClass matraClass)
{
// FIXME: check if already set, or if not a matra...
if (IndicClassTable::isMpre(matraClass)) {
fMpre = matra;
} else if (IndicClassTable::isMbelow(matraClass)) {
fMbelow = matra;
} else if (IndicClassTable::isMabove(matraClass)) {
fMabove = matra;
} else if (IndicClassTable::isMpost(matraClass)) {
fMpost = matra;
} else if (IndicClassTable::isLengthMark(matraClass)) {
fLengthMark = matra;
}
}
public:
ReorderingOutput(LEUnicode *outChars, le_int32 *charIndices, const LETag **charTags)
: fOutIndex(0), fOutChars(outChars), fCharIndices(charIndices), fCharTags(charTags),
fMpre(0), fMbelow(0), fMabove(0), fMpost(0), fLengthMark(0),
fMatraIndex(0), fMatraTags(NULL)
{
// nothing else to do...
}
~ReorderingOutput()
{
// nothing to do here...
}
void noteMatra(const IndicClassTable *classTable, LEUnicode matra, le_uint32 matraIndex, const LETag *matraTags)
{
IndicClassTable::CharClass matraClass = classTable->getCharClass(matra);
fMpre = fMbelow = fMabove = fMpost = fLengthMark = 0;
fMatraIndex = matraIndex;
fMatraTags = matraTags;
if (IndicClassTable::isMatra(matraClass)) {
if (IndicClassTable::isSplitMatra(matraClass)) {
const SplitMatra *splitMatra = classTable->getSplitMatra(matraClass);
int i;
for (i = 0; i < 3 && (*splitMatra)[i] != 0; i += 1) {
LEUnicode piece = (*splitMatra)[i];
IndicClassTable::CharClass pieceClass = classTable->getCharClass(piece);
saveMatra(piece, pieceClass);
}
} else {
saveMatra(matra, matraClass);
}
}
}
void writeMpre()
{
if (fMpre != 0) {
writeChar(fMpre, fMatraIndex, fMatraTags);
}
}
void writeMbelow()
{
if (fMbelow != 0) {
writeChar(fMbelow, fMatraIndex, fMatraTags);
}
}
void writeMabove()
{
if (fMabove != 0) {
writeChar(fMabove, fMatraIndex, fMatraTags);
}
}
void writeMpost()
{
if (fMpost != 0) {
writeChar(fMpost, fMatraIndex, fMatraTags);
}
}
void writeLengthMark()
{
if (fLengthMark != 0) {
writeChar(fLengthMark, fMatraIndex, fMatraTags);
}
}
void writeChar(LEUnicode ch, le_uint32 charIndex, const LETag *charTags)
{
fOutChars[fOutIndex] = ch;
fCharIndices[fOutIndex] = charIndex;
fCharTags[fOutIndex] = charTags;
fOutIndex += 1;
}
le_int32 getOutputIndex()
{
return fOutIndex;
}
};
enum
{
C_DOTTED_CIRCLE = 0x25CC
};
const LETag emptyTag = 0x00000000; // ''
const LETag nuktFeatureTag = 0x6E756B74; // 'nukt'
const LETag akhnFeatureTag = 0x616B686E; // 'akhn'
const LETag rphfFeatureTag = 0x72706866; // 'rphf'
const LETag blwfFeatureTag = 0x626C7766; // 'blwf'
const LETag halfFeatureTag = 0x68616C66; // 'half'
const LETag pstfFeatureTag = 0x70737466; // 'pstf'
const LETag vatuFeatureTag = 0x76617475; // 'vatu'
const LETag presFeatureTag = 0x70726573; // 'pres'
const LETag blwsFeatureTag = 0x626C7773; // 'blws'
const LETag abvsFeatureTag = 0x61627673; // 'abvs'
const LETag pstsFeatureTag = 0x70737473; // 'psts'
const LETag halnFeatureTag = 0x68616C6E; // 'haln'
const LETag blwmFeatureTag = 0x626C776D; // 'blwm'
const LETag abvmFeatureTag = 0x6162766D; // 'abvm'
const LETag distFeatureTag = 0x64697374; // 'dist'
// FIXME: do we want a seperate tag array for each kind of character??
const LETag tagArray[] =
{
rphfFeatureTag, blwfFeatureTag, halfFeatureTag, nuktFeatureTag, akhnFeatureTag, pstfFeatureTag,
vatuFeatureTag, presFeatureTag, blwsFeatureTag, abvsFeatureTag, pstsFeatureTag, halnFeatureTag,
blwmFeatureTag, abvmFeatureTag, emptyTag
};
const le_int8 stateTable[][IndicClassTable::CC_COUNT] =
{
// xx ma mp iv ct cn nu dv vr zw
{ 1, 1, 1, 5, 3, 2, 1, 1, 1, 1},
{-1, -1, -1, -1, -1, -1, -1, -1, -1, -1},
{-1, 6, 1, -1, -1, -1, -1, 5, 4, -1},
{-1, 6, 1, -1, -1, -1, 2, 5, 4, -1},
{-1, -1, -1, -1, 3, 2, -1, -1, -1, 8},
{-1, 6, 1, -1, -1, -1, -1, -1, -1, -1},
{-1, 7, 1, -1, -1, -1, -1, -1, -1, -1},
{-1, -1, 1, -1, -1, -1, -1, -1, -1, -1},
{-1, -1, -1, -1, 3, 2, -1, -1, -1, -1}
};
le_int32 IndicReordering::findSyllable(const IndicClassTable *classTable, const LEUnicode *chars, le_int32 prev, le_int32 charCount)
{
le_int32 cursor = prev;
le_int8 state = 0;
while (cursor < charCount) {
IndicClassTable::CharClass charClass = classTable->getCharClass(chars[cursor]);
state = stateTable[state][charClass & IndicClassTable::CF_CLASS_MASK];
if (state < 0) {
break;
}
cursor += 1;
}
return cursor;
}
le_int32 IndicReordering::reorder(const LEUnicode *chars, le_int32 charCount, le_int32 scriptCode, LEUnicode *outChars, le_int32 *charIndices, const LETag **charTags)
{
const IndicClassTable *classTable = IndicClassTable::getScriptClassTable(scriptCode);
ReorderingOutput output(outChars, charIndices, charTags);
le_int32 i, prev = 0;
while (prev < charCount) {
le_int32 syllable = findSyllable(classTable, chars, prev, charCount);
le_int32 matra, vmabove, vmpost = syllable;
le_int16 flags = 0;
while (vmpost > prev && classTable->isVMpost(chars[vmpost - 1])) {
vmpost -= 1;
}
vmabove = vmpost;
while (vmabove > prev && classTable->isVMabove(chars[vmabove - 1])) {
vmabove -= 1;
}
matra = vmabove - 1;
output.noteMatra(classTable, chars[matra], matra, &tagArray[1]);
switch (classTable->getCharClass(chars[prev]) & IndicClassTable::CF_CLASS_MASK) {
case IndicClassTable::CC_RESERVED:
case IndicClassTable::CC_INDEPENDENT_VOWEL:
case IndicClassTable::CC_ZERO_WIDTH_MARK:
for (i = prev; i < syllable; i += 1) {
output.writeChar(chars[i], i, &tagArray[1]);
}
break;
case IndicClassTable::CC_MODIFYING_MARK_ABOVE:
case IndicClassTable::CC_MODIFYING_MARK_POST:
case IndicClassTable::CC_NUKTA:
case IndicClassTable::CC_VIRAMA:
output.writeChar(C_DOTTED_CIRCLE, prev, &tagArray[1]);
output.writeChar(chars[prev], prev, &tagArray[1]);
break;
case IndicClassTable::CC_DEPENDENT_VOWEL:
output.writeMpre();
output.writeChar(C_DOTTED_CIRCLE, prev, &tagArray[1]);
output.writeMbelow();
output.writeMabove();
output.writeMpost();
output.writeLengthMark();
break;
case IndicClassTable::CC_CONSONANT:
case IndicClassTable::CC_CONSONANT_WITH_NUKTA:
{
le_uint32 length = vmabove - prev;
le_int32 lastConsonant = vmabove - 1;
le_int32 baseLimit = prev;
// Check for REPH at front of syllable
if (length > 2 && classTable->isReph(chars[prev]) && classTable->isVirama(chars[prev + 1])) {
baseLimit = prev + 2;
// Check for eyelash RA, if the script supports it
if ((classTable->scriptFlags & IndicClassTable::SF_EYELASH_RA) != 0 &&
chars[prev + 2] == C_SIGN_ZWJ) {
if (length > 3) {
baseLimit += 1;
} else {
baseLimit = prev;
}
}
}
while (lastConsonant >= baseLimit && !classTable->isConsonant(chars[lastConsonant])) {
lastConsonant -= 1;
}
le_int32 baseConsonant = lastConsonant;
le_int32 postBase = lastConsonant + 1;
if (lastConsonant >= prev) {
int postBaseLimit = classTable->scriptFlags & IndicClassTable::SF_POST_BASE_LIMIT_MASK;
le_bool seenVattu = false;
le_bool seenBelowBaseForm = false;
while (baseConsonant >= baseLimit) {
IndicClassTable::CharClass charClass = classTable->getCharClass(chars[baseConsonant]);
if (IndicClassTable::isConsonant(charClass)) {
if (postBaseLimit == 0 || seenVattu ||
(baseConsonant > baseLimit && !classTable->isVirama(chars[baseConsonant - 1])) ||
!IndicClassTable::hasPostOrBelowBaseForm(charClass)) {
break;
}
seenVattu = IndicClassTable::isVattu(charClass);
if (IndicClassTable::hasPostBaseForm(charClass)) {
if (seenBelowBaseForm) {
break;
}
postBase = baseConsonant;
} else if (IndicClassTable::hasBelowBaseForm(charClass)) {
seenBelowBaseForm = true;
}
postBaseLimit -= 1;
}
baseConsonant -= 1;
}
if (baseConsonant < baseLimit) {
baseConsonant = baseLimit;
}
// Write Mpre
output.writeMpre();
// Write eyelash RA
// NOTE: baseLimit == prev + 3 iff eyelash RA present...
if (baseLimit == prev + 3) {
output.writeChar(chars[prev], prev, &tagArray[2]);
output.writeChar(chars[prev + 1], prev + 1, &tagArray[2]);
output.writeChar(chars[prev + 2], prev + 2, &tagArray[2]);
}
// write any pre-base consonants
le_bool supressVattu = true;
for (i = baseLimit; i < baseConsonant; i += 1) {
LEUnicode ch = chars[i];
const LETag *tag = &tagArray[1];
IndicClassTable::CharClass charClass = classTable->getCharClass(ch);
if (IndicClassTable::isConsonant(charClass)) {
if (IndicClassTable::isVattu(charClass) && supressVattu) {
tag = &tagArray[3];
}
supressVattu = IndicClassTable::isVattu(charClass);
} else if (IndicClassTable::isVirama(charClass) && chars[i + 1] == C_SIGN_ZWNJ)
{
tag = &tagArray[3];
}
output.writeChar(ch, i, tag);
}
le_int32 bcSpan = baseConsonant + 1;
if (bcSpan < vmabove && classTable->isNukta(chars[bcSpan])) {
bcSpan += 1;
}
if (baseConsonant == lastConsonant && bcSpan < vmabove && classTable->isVirama(chars[bcSpan])) {
bcSpan += 1;
if (bcSpan < vmabove && chars[bcSpan] == C_SIGN_ZWNJ) {
bcSpan += 1;
}
}
// write base consonant
for (i = baseConsonant; i < bcSpan; i += 1) {
output.writeChar(chars[i], i, &tagArray[3]);
}
if ((classTable->scriptFlags & IndicClassTable::SF_MATRAS_AFTER_BASE) != 0) {
output.writeMbelow();
output.writeMabove();
output.writeMpost();
}
// write below-base consonants
if (baseConsonant != lastConsonant) {
for (i = bcSpan + 1; i < postBase; i += 1) {
output.writeChar(chars[i], i, &tagArray[1]);
}
if (postBase > lastConsonant) {
// write halant that was after base consonant
output.writeChar(chars[bcSpan], bcSpan, &tagArray[1]);
}
}
// write Mbelow, Mabove
if ((classTable->scriptFlags & IndicClassTable::SF_MATRAS_AFTER_BASE) == 0) {
output.writeMbelow();
output.writeMabove();
}
if ((classTable->scriptFlags & IndicClassTable::SF_REPH_AFTER_BELOW) != 0) {
if (baseLimit == prev + 2) {
output.writeChar(chars[prev], prev, &tagArray[0]);
output.writeChar(chars[prev + 1], prev + 1, &tagArray[0]);
}
// write VMabove
for (i = vmabove; i < vmpost; i += 1) {
output.writeChar(chars[i], i, &tagArray[1]);
}
}
// write post-base consonants
// FIXME: does this put the right tags on post-base consonants?
if (baseConsonant != lastConsonant) {
if (postBase <= lastConsonant) {
for (i = postBase; i <= lastConsonant; i += 1) {
output.writeChar(chars[i], i, &tagArray[3]);
}
// write halant that was after base consonant
output.writeChar(chars[bcSpan], bcSpan, &tagArray[1]);
}
// write the training halant, if there is one
if (lastConsonant < matra && classTable->isVirama(chars[matra])) {
output.writeChar(chars[matra], matra, &tagArray[3]);
}
}
// write Mpost
if ((classTable->scriptFlags & IndicClassTable::SF_MATRAS_AFTER_BASE) == 0) {
output.writeMpost();
}
output.writeLengthMark();
// write reph
if ((classTable->scriptFlags & IndicClassTable::SF_REPH_AFTER_BELOW) == 0) {
if (baseLimit == prev + 2) {
output.writeChar(chars[prev], prev, &tagArray[0]);
output.writeChar(chars[prev + 1], prev + 1, &tagArray[0]);
}
// write VMabove
for (i = vmabove; i < vmpost; i += 1) {
output.writeChar(chars[i], i, &tagArray[1]);
}
}
// write VMpost
for (i = vmpost; i < syllable; i += 1) {
output.writeChar(chars[i], i, &tagArray[1]);
}
}
break;
}
default:
break;
}
prev = syllable;
}
return output.getOutputIndex();
}
void IndicReordering::adjustMPres(const LEUnicode *chars, le_int32 charCount, LEGlyphID *glyphs, le_int32 *charIndices, le_int32 scriptCode)
{
const IndicClassTable *classTable = IndicClassTable::getScriptClassTable(scriptCode);
if (classTable->scriptFlags & IndicClassTable::SF_MPRE_FIXUP) {
le_int32 i;
for (i = 0; i < charCount; i += 1) {
if (classTable->isMpre(chars[i])) {
le_int32 j;
le_bool cflag = true;
for (j = i + 1; j < charCount; j += 1) {
IndicClassTable::CharClass charClass = classTable->getCharClass(chars[j]);
if (IndicClassTable::isConsonant(charClass)) {
if (! cflag) {
break;
}
cflag = false;
} else if (IndicClassTable::isVirama(charClass)) {
if (cflag) {
break;
}
cflag = true;
} else {
break;
}
}
// Don't bother to reorder if
// there's one or fewer consonants
if (j <= i + 2) {
continue;
}
int lastConsonant = j - 1;
int base;
for (base = lastConsonant; base > i; base -= 1) {
if (classTable->isConsonant(chars[base]) && glyphs[base] != 0xFFFF) {
break;
}
}
LEGlyphID matra = glyphs[i];
le_int32 mIndex = charIndices[i];
le_int32 x;
for (x = i; x < base - 1; x += 1) {
glyphs[x] = glyphs[x + 1];
charIndices[x] = charIndices[x + 1];
}
glyphs[base - 1] = matra;
charIndices[base - 1] = mIndex;
}
}
}
}
U_NAMESPACE_END