1 /*
2 *
3 * (C) Copyright IBM Corp. 1998-2008 - All Rights Reserved
4 *
5 */
6
7 #include "LETypes.h"
8 #include "LEGlyphFilter.h"
9 #include "OpenTypeTables.h"
10 #include "GlyphSubstitutionTables.h"
11 #include "MultipleSubstSubtables.h"
12 #include "GlyphIterator.h"
13 #include "LESwaps.h"
14
15 U_NAMESPACE_BEGIN
16
process(GlyphIterator * glyphIterator,LEErrorCode & success,const LEGlyphFilter * filter) const17 le_uint32 MultipleSubstitutionSubtable::process(GlyphIterator *glyphIterator, LEErrorCode& success, const LEGlyphFilter *filter) const
18 {
19 if (LE_FAILURE(success)) {
20 return 0;
21 }
22
23 LEGlyphID glyph = glyphIterator->getCurrGlyphID();
24
25 // If there's a filter, we only want to do the
26 // substitution if the *input* glyphs doesn't
27 // exist.
28 //
29 // FIXME: is this always the right thing to do?
30 // FIXME: should this only be done for a non-zero
31 // glyphCount?
32 if (filter != NULL && filter->accept(glyph)) {
33 return 0;
34 }
35
36 le_int32 coverageIndex = getGlyphCoverage(glyph);
37 le_uint16 seqCount = SWAPW(sequenceCount);
38
39 if (coverageIndex >= 0 && coverageIndex < seqCount) {
40 Offset sequenceTableOffset = SWAPW(sequenceTableOffsetArray[coverageIndex]);
41 const SequenceTable *sequenceTable = (const SequenceTable *) ((char *) this + sequenceTableOffset);
42 le_uint16 glyphCount = SWAPW(sequenceTable->glyphCount);
43
44 if (glyphCount == 0) {
45 glyphIterator->setCurrGlyphID(0xFFFF);
46 return 1;
47 } else if (glyphCount == 1) {
48 TTGlyphID substitute = SWAPW(sequenceTable->substituteArray[0]);
49
50 if (filter != NULL && ! filter->accept(LE_SET_GLYPH(glyph, substitute))) {
51 return 0;
52 }
53
54 glyphIterator->setCurrGlyphID(substitute);
55 return 1;
56 } else {
57 // If there's a filter, make sure all of the output glyphs
58 // exist.
59 if (filter != NULL) {
60 for (le_int32 i = 0; i < glyphCount; i += 1) {
61 TTGlyphID substitute = SWAPW(sequenceTable->substituteArray[i]);
62
63 if (! filter->accept(substitute)) {
64 return 0;
65 }
66 }
67 }
68
69 LEGlyphID *newGlyphs = glyphIterator->insertGlyphs(glyphCount, success);
70 if (LE_FAILURE(success)) {
71 return 0;
72 }
73
74 le_int32 insert = 0, direction = 1;
75
76 if (glyphIterator->isRightToLeft()) {
77 insert = glyphCount - 1;
78 direction = -1;
79 }
80
81 for (le_int32 i = 0; i < glyphCount; i += 1) {
82 TTGlyphID substitute = SWAPW(sequenceTable->substituteArray[i]);
83
84 newGlyphs[insert] = LE_SET_GLYPH(glyph, substitute);
85 insert += direction;
86 }
87
88 return 1;
89 }
90 }
91
92 return 0;
93 }
94
95 U_NAMESPACE_END
96