1 /*
2 *
3 * (C) Copyright IBM Corp. 1998-2004 - All Rights Reserved
4 *
5 */
6
7 #include "LETypes.h"
8 #include "LEFontInstance.h"
9 #include "OpenTypeTables.h"
10 #include "AnchorTables.h"
11 #include "MarkArrays.h"
12 #include "GlyphPositioningTables.h"
13 #include "AttachmentPosnSubtables.h"
14 #include "MarkToBasePosnSubtables.h"
15 #include "GlyphIterator.h"
16 #include "LESwaps.h"
17
18 U_NAMESPACE_BEGIN
19
findBaseGlyph(GlyphIterator * glyphIterator) const20 LEGlyphID MarkToBasePositioningSubtable::findBaseGlyph(GlyphIterator *glyphIterator) const
21 {
22 if (glyphIterator->prev()) {
23 return glyphIterator->getCurrGlyphID();
24 }
25
26 return 0xFFFF;
27 }
28
process(GlyphIterator * glyphIterator,const LEFontInstance * fontInstance) const29 le_int32 MarkToBasePositioningSubtable::process(GlyphIterator *glyphIterator, const LEFontInstance *fontInstance) const
30 {
31 LEGlyphID markGlyph = glyphIterator->getCurrGlyphID();
32 le_int32 markCoverage = getGlyphCoverage((LEGlyphID) markGlyph);
33
34 if (markCoverage < 0) {
35 // markGlyph isn't a covered mark glyph
36 return 0;
37 }
38
39 LEPoint markAnchor;
40 const MarkArray *markArray = (const MarkArray *) ((char *) this + SWAPW(markArrayOffset));
41 le_int32 markClass = markArray->getMarkClass(markGlyph, markCoverage, fontInstance, markAnchor);
42 le_uint16 mcCount = SWAPW(classCount);
43
44 if (markClass < 0 || markClass >= mcCount) {
45 // markGlyph isn't in the mark array or its
46 // mark class is too big. The table is mal-formed!
47 return 0;
48 }
49
50 // FIXME: We probably don't want to find a base glyph before a previous ligature...
51 GlyphIterator baseIterator(*glyphIterator, (le_uint16) (lfIgnoreMarks /*| lfIgnoreLigatures*/));
52 LEGlyphID baseGlyph = findBaseGlyph(&baseIterator);
53 le_int32 baseCoverage = getBaseCoverage((LEGlyphID) baseGlyph);
54 const BaseArray *baseArray = (const BaseArray *) ((char *) this + SWAPW(baseArrayOffset));
55 le_uint16 baseCount = SWAPW(baseArray->baseRecordCount);
56
57 if (baseCoverage < 0 || baseCoverage >= baseCount) {
58 // The base glyph isn't covered, or the coverage
59 // index is too big. The latter means that the
60 // table is mal-formed...
61 return 0;
62 }
63
64 const BaseRecord *baseRecord = &baseArray->baseRecordArray[baseCoverage * mcCount];
65 Offset anchorTableOffset = SWAPW(baseRecord->baseAnchorTableOffsetArray[markClass]);
66 const AnchorTable *anchorTable = (const AnchorTable *) ((char *) baseArray + anchorTableOffset);
67 LEPoint baseAnchor, markAdvance, pixels;
68
69 if (anchorTableOffset == 0) {
70 // this means the table is mal-formed...
71 glyphIterator->setCurrGlyphBaseOffset(baseIterator.getCurrStreamPosition());
72 return 0;
73 }
74
75 anchorTable->getAnchor(baseGlyph, fontInstance, baseAnchor);
76
77 fontInstance->getGlyphAdvance(markGlyph, pixels);
78 fontInstance->pixelsToUnits(pixels, markAdvance);
79
80 float anchorDiffX = baseAnchor.fX - markAnchor.fX;
81 float anchorDiffY = baseAnchor.fY - markAnchor.fY;
82
83 glyphIterator->setCurrGlyphBaseOffset(baseIterator.getCurrStreamPosition());
84
85 if (glyphIterator->isRightToLeft()) {
86 glyphIterator->setCurrGlyphPositionAdjustment(anchorDiffX, anchorDiffY, -markAdvance.fX, -markAdvance.fY);
87 } else {
88 LEPoint baseAdvance;
89
90 fontInstance->getGlyphAdvance(baseGlyph, pixels);
91 fontInstance->pixelsToUnits(pixels, baseAdvance);
92
93 glyphIterator->setCurrGlyphPositionAdjustment(anchorDiffX - baseAdvance.fX, anchorDiffY - baseAdvance.fY, -markAdvance.fX, -markAdvance.fY);
94 }
95
96 return 1;
97 }
98
99 U_NAMESPACE_END
100