sl@0: /*
sl@0:  *
sl@0:  * (C) Copyright IBM Corp. 1998-2004 - All Rights Reserved
sl@0:  *
sl@0:  */
sl@0: 
sl@0: #include "LETypes.h"
sl@0: #include "LEGlyphFilter.h"
sl@0: #include "OpenTypeTables.h"
sl@0: #include "GlyphSubstitutionTables.h"
sl@0: #include "MultipleSubstSubtables.h"
sl@0: #include "GlyphIterator.h"
sl@0: #include "LESwaps.h"
sl@0: 
sl@0: U_NAMESPACE_BEGIN
sl@0: 
sl@0: le_uint32 MultipleSubstitutionSubtable::process(GlyphIterator *glyphIterator, LEErrorCode& success,
sl@0:     const LEGlyphFilter *filter) const
sl@0: {
sl@0:     if (LE_FAILURE(success)) {
sl@0:         return 0;
sl@0:     }
sl@0: 
sl@0:     LEGlyphID glyph = glyphIterator->getCurrGlyphID();
sl@0: 
sl@0:     // If there's a filter, we only want to do the
sl@0:     // substitution if the *input* glyphs doesn't
sl@0:     // exist.
sl@0:     //
sl@0:     // FIXME: is this always the right thing to do?
sl@0:     // FIXME: should this only be done for a non-zero
sl@0:     //        glyphCount?
sl@0:     if (filter != NULL && filter->accept(glyph)) {
sl@0:         return 0;
sl@0:     }
sl@0: 
sl@0:     le_int32 coverageIndex = getGlyphCoverage(glyph);
sl@0:     le_uint16 seqCount = SWAPW(sequenceCount);
sl@0: 
sl@0:     if (coverageIndex >= 0 && coverageIndex < seqCount) {
sl@0:         Offset sequenceTableOffset = SWAPW(sequenceTableOffsetArray[coverageIndex]);
sl@0:         const SequenceTable *sequenceTable = (const SequenceTable *) ((char *) this + sequenceTableOffset);
sl@0:         le_uint16 glyphCount = SWAPW(sequenceTable->glyphCount);
sl@0: 
sl@0:         if (glyphCount == 0) {
sl@0:             glyphIterator->setCurrGlyphID(0xFFFF);
sl@0:             return 1;
sl@0:         } else if (glyphCount == 1) {
sl@0:             TTGlyphID substitute = SWAPW(sequenceTable->substituteArray[0]);
sl@0: 
sl@0:             if (filter != NULL && ! filter->accept(LE_SET_GLYPH(glyph, substitute))) {
sl@0:                 return 0;
sl@0:             }
sl@0: 
sl@0:             glyphIterator->setCurrGlyphID(substitute);
sl@0:             return 1;
sl@0:         } else {
sl@0:             // If there's a filter, make sure all of the output glyphs
sl@0:             // exist.
sl@0:             if (filter != NULL) {
sl@0:                 for (le_int32 i = 0; i < glyphCount; i += 1) {
sl@0:                     TTGlyphID substitute = SWAPW(sequenceTable->substituteArray[i]);
sl@0: 
sl@0:                     if (! filter->accept(substitute)) {
sl@0:                         return 0;
sl@0:                     }
sl@0:                 }
sl@0:             }
sl@0: 
sl@0:             LEGlyphID *newGlyphs = glyphIterator->insertGlyphs(glyphCount, success);
sl@0:             if (LE_FAILURE(success)) {
sl@0:                 return 0;
sl@0:             }
sl@0: 
sl@0:             le_int32 insert = 0, direction = 1;
sl@0: 
sl@0:             if (glyphIterator->isRightToLeft()) {
sl@0:                 insert = glyphCount - 1;
sl@0:                 direction = -1;
sl@0:             }
sl@0: 
sl@0:             for (le_int32 i = 0; i < glyphCount; i += 1) {
sl@0:                 TTGlyphID substitute = SWAPW(sequenceTable->substituteArray[i]);
sl@0: 
sl@0:                 newGlyphs[insert] = LE_SET_GLYPH(glyph, substitute);
sl@0:                 insert += direction;
sl@0:             }
sl@0: 
sl@0:             return 1;
sl@0:         }
sl@0:     }
sl@0: 
sl@0:     return 0;
sl@0: }
sl@0: 
sl@0: U_NAMESPACE_END