1 /*

     2  * %W% %E%

     3  *

     4  * (C) Copyright IBM Corp. 1998-2003 - All Rights Reserved

     5  *

     6  */

     7 

     8 #include "LETypes.h"

     9 #include "LEGlyphFilter.h"

    10 #include "OpenTypeTables.h"

    11 #include "GlyphSubstitutionTables.h"

    12 #include "LigatureSubstSubtables.h"

    13 #include "GlyphIterator.h"

    14 #include "LESwaps.h"

    15 

    16 U_NAMESPACE_BEGIN

    17 

    18 le_uint32 LigatureSubstitutionSubtable::process(GlyphIterator *glyphIterator, const LEGlyphFilter *filter) const

    19 {

    20     LEGlyphID glyph = glyphIterator->getCurrGlyphID();

    21     le_int32 coverageIndex = getGlyphCoverage(glyph);

    22 

    23     if (coverageIndex >= 0) {

    24         Offset ligSetTableOffset = SWAPW(ligSetTableOffsetArray[coverageIndex]);

    25         const LigatureSetTable *ligSetTable = (const LigatureSetTable *) ((char *) this + ligSetTableOffset);

    26         le_uint16 ligCount = SWAPW(ligSetTable->ligatureCount);

    27 

    28         for (le_uint16 lig = 0; lig < ligCount; lig += 1) {

    29             Offset ligTableOffset = SWAPW(ligSetTable->ligatureTableOffsetArray[lig]);

    30             const LigatureTable *ligTable = (const LigatureTable *) ((char *)ligSetTable + ligTableOffset);

    31             le_uint16 compCount = SWAPW(ligTable->compCount) - 1;

    32             le_int32 startPosition = glyphIterator->getCurrStreamPosition();

    33             TTGlyphID ligGlyph = SWAPW(ligTable->ligGlyph);

    34             le_uint16 comp;

    35 

    36             if (filter != NULL && ! filter->accept(LE_SET_GLYPH(glyph, ligGlyph))) {

    37                 continue;

    38             }

    39 

    40             for (comp = 0; comp < compCount; comp += 1) {

    41                 if (! glyphIterator->next()) {

    42                     break;

    43                 }

    44 

    45                 if (LE_GET_GLYPH(glyphIterator->getCurrGlyphID()) != SWAPW(ligTable->componentArray[comp])) {

    46                     break;

    47                 }

    48             }

    49 

    50             if (comp == compCount) {

    51                 GlyphIterator tempIterator(*glyphIterator);

    52                 TTGlyphID deletedGlyph = tempIterator.ignoresMarks()? 0xFFFE : 0xFFFF;

    53 

    54                 while (comp > 0) {

    55                     tempIterator.setCurrGlyphID(deletedGlyph);

    56                     tempIterator.prev();

    57 

    58                     comp -= 1;

    59                 }

    60 

    61                 tempIterator.setCurrGlyphID(ligGlyph);

    62 

    63                 return compCount + 1;

    64             }

    65 

    66             glyphIterator->setCurrStreamPosition(startPosition);

    67         }

    68 

    69     }

    70 

    71     return 0;

    72 }

    73 

    74 U_NAMESPACE_END