1 /*
2 *
3 * (C) Copyright IBM Corp. 1998-2015 - 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(const LETableReference & base,GlyphIterator * glyphIterator,LEErrorCode & success,const LEGlyphFilter * filter) const17 le_uint32 MultipleSubstitutionSubtable::process(const LETableReference &base, 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(base, glyph, success);
37 le_uint16 seqCount = SWAPW(sequenceCount);
38 LEReferenceToArrayOf<Offset>
39 sequenceTableOffsetArrayRef(base, success, sequenceTableOffsetArray, seqCount);
40
41 if (LE_FAILURE(success)) {
42 return 0;
43 }
44 if (coverageIndex >= 0 && coverageIndex < seqCount) {
45 Offset sequenceTableOffset = SWAPW(sequenceTableOffsetArray[coverageIndex]);
46 const SequenceTable *sequenceTable = (const SequenceTable *) ((char *) this + sequenceTableOffset);
47 le_uint16 glyphCount = SWAPW(sequenceTable->glyphCount);
48
49 if (glyphCount == 0) {
50 glyphIterator->setCurrGlyphID(0xFFFF);
51 return 1;
52 } else if (glyphCount == 1) {
53 TTGlyphID substitute = SWAPW(sequenceTable->substituteArray[0]);
54
55 if (filter != NULL && ! filter->accept(LE_SET_GLYPH(glyph, substitute))) {
56 return 0;
57 }
58
59 glyphIterator->setCurrGlyphID(substitute);
60 return 1;
61 } else {
62 // If there's a filter, make sure all of the output glyphs
63 // exist.
64 if (filter != NULL) {
65 for (le_int32 i = 0; i < glyphCount; i += 1) {
66 TTGlyphID substitute = SWAPW(sequenceTable->substituteArray[i]);
67
68 if (! filter->accept(substitute)) {
69 return 0;
70 }
71 }
72 }
73
74 LEGlyphID *newGlyphs = glyphIterator->insertGlyphs(glyphCount, success);
75 if (LE_FAILURE(success)) {
76 return 0;
77 }
78
79 le_int32 insert = 0, direction = 1;
80
81 if (glyphIterator->isRightToLeft()) {
82 insert = glyphCount - 1;
83 direction = -1;
84 }
85
86 for (le_int32 i = 0; i < glyphCount; i += 1) {
87 TTGlyphID substitute = SWAPW(sequenceTable->substituteArray[i]);
88
89 newGlyphs[insert] = LE_SET_GLYPH(glyph, substitute);
90 insert += direction;
91 }
92
93 return 1;
94 }
95 }
96
97 return 0;
98 }
99
100 U_NAMESPACE_END
101