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/*
*
* (C) Copyright IBM Corp. 1998-2004 - All Rights Reserved
*
*/
#include "LETypes.h"
#include "MorphTables.h"
#include "StateTables.h"
#include "MorphStateTables.h"
#include "SubtableProcessor.h"
#include "StateTableProcessor.h"
#include "LigatureSubstProc.h"
#include "LEGlyphStorage.h"
#include "LESwaps.h"
U_NAMESPACE_BEGIN
#define ExtendedComplement(m) ((le_int32) (~((le_uint32) (m))))
#define SignBit(m) ((ExtendedComplement(m) >> 1) & (le_int32)(m))
#define SignExtend(v,m) (((v) & SignBit(m))? ((v) | ExtendedComplement(m)): (v))
UOBJECT_DEFINE_RTTI_IMPLEMENTATION(LigatureSubstitutionProcessor)
LigatureSubstitutionProcessor::LigatureSubstitutionProcessor(const MorphSubtableHeader *morphSubtableHeader)
: StateTableProcessor(morphSubtableHeader)
{
ligatureSubstitutionHeader = (const LigatureSubstitutionHeader *) morphSubtableHeader;
ligatureActionTableOffset = SWAPW(ligatureSubstitutionHeader->ligatureActionTableOffset);
componentTableOffset = SWAPW(ligatureSubstitutionHeader->componentTableOffset);
ligatureTableOffset = SWAPW(ligatureSubstitutionHeader->ligatureTableOffset);
entryTable = (const LigatureSubstitutionStateEntry *) ((char *) &stateTableHeader->stHeader + entryTableOffset);
}
LigatureSubstitutionProcessor::~LigatureSubstitutionProcessor()
{
}
void LigatureSubstitutionProcessor::beginStateTable()
{
m = -1;
}
ByteOffset LigatureSubstitutionProcessor::processStateEntry(LEGlyphStorage &glyphStorage, le_int32 &currGlyph, EntryTableIndex index)
{
const LigatureSubstitutionStateEntry *entry = &entryTable[index];
ByteOffset newState = SWAPW(entry->newStateOffset);
le_int16 flags = SWAPW(entry->flags);
if (flags & lsfSetComponent) {
if (++m >= nComponents) {
m = 0;
}
componentStack[m] = currGlyph;
}
ByteOffset actionOffset = flags & lsfActionOffsetMask;
if (actionOffset != 0) {
const LigatureActionEntry *ap = (const LigatureActionEntry *) ((char *) &ligatureSubstitutionHeader->stHeader + actionOffset);
LigatureActionEntry action;
le_int32 offset, i = 0;
le_int32 stack[nComponents];
le_int16 mm = -1;
do {
le_uint32 componentGlyph = componentStack[m--];
action = SWAPL(*ap++);
if (m < 0) {
m = nComponents - 1;
}
offset = action & lafComponentOffsetMask;
if (offset != 0) {
const le_int16 *offsetTable = (const le_int16 *)((char *) &ligatureSubstitutionHeader->stHeader + 2 * SignExtend(offset, lafComponentOffsetMask));
i += SWAPW(offsetTable[LE_GET_GLYPH(glyphStorage[componentGlyph])]);
if (action & (lafLast | lafStore)) {
const TTGlyphID *ligatureOffset = (const TTGlyphID *) ((char *) &ligatureSubstitutionHeader->stHeader + i);
TTGlyphID ligatureGlyph = SWAPW(*ligatureOffset);
glyphStorage[componentGlyph] = LE_SET_GLYPH(glyphStorage[componentGlyph], ligatureGlyph);
stack[++mm] = componentGlyph;
i = 0;
} else {
glyphStorage[componentGlyph] = LE_SET_GLYPH(glyphStorage[componentGlyph], 0xFFFF);
}
}
} while (!(action & lafLast));
while (mm >= 0) {
if (++m >= nComponents) {
m = 0;
}
componentStack[m] = stack[mm--];
}
}
if (!(flags & lsfDontAdvance)) {
// should handle reverse too!
currGlyph += 1;
}
return newState;
}
void LigatureSubstitutionProcessor::endStateTable()
{
}
U_NAMESPACE_END