scuffed-code/icu4c/source/layout/MarkToBasePosnSubtables.cpp
2001-01-19 00:30:17 +00:00

94 lines
3.2 KiB
C++

/*
* @(#)MarkToBasePosnSubtables.cpp 1.5 00/03/15
*
* (C) Copyright IBM Corp. 1998, 1999, 2000, 2001 - All Rights Reserved
*
*/
#include "LETypes.h"
#include "LEFontInstance.h"
#include "OpenTypeTables.h"
#include "AnchorTables.h"
#include "MarkArrays.h"
#include "GlyphPositioningTables.h"
#include "AttachmentPosnSubtables.h"
#include "MarkToBasePosnSubtables.h"
#include "GlyphIterator.h"
#include "LESwaps.h"
LEGlyphID MarkToBasePositioningSubtable::findBaseGlyph(GlyphIterator *glyphIterator) const
{
if (glyphIterator->prev()) {
return glyphIterator->getCurrGlyphID();
}
return 0xFFFF;
}
le_int32 MarkToBasePositioningSubtable::process(GlyphIterator *glyphIterator, const LEFontInstance *fontInstance) const
{
LEGlyphID markGlyph = glyphIterator->getCurrGlyphID();
le_int32 markCoverage = getGlyphCoverage((LEGlyphID) markGlyph);
if (markCoverage < 0) {
// markGlyph isn't a covered mark glyph
return 0;
}
LEPoint markAnchor;
const MarkArray *markArray = (const MarkArray *) ((char *) this + SWAPW(markArrayOffset));
le_int32 markClass = markArray->getMarkClass(markGlyph, markCoverage, fontInstance, markAnchor);
le_uint16 mcCount = SWAPW(classCount);
if (markClass < 0 || markClass >= mcCount) {
// markGlyph isn't in the mark array or its
// mark class is too big. The table is mal-formed!
return 0;
}
// FIXME: We probably don't want to find a base glyph before a previous ligature...
GlyphIterator baseIterator(*glyphIterator, lfIgnoreMarks /*| lfIgnoreLigatures*/);
LEGlyphID baseGlyph = findBaseGlyph(&baseIterator);
le_int32 baseCoverage = getBaseCoverage((LEGlyphID) baseGlyph);
const BaseArray *baseArray = (const BaseArray *) ((char *) this + SWAPW(baseArrayOffset));
le_uint16 baseCount = SWAPW(baseArray->baseRecordCount);
if (baseCoverage < 0 || baseCoverage >= baseCount) {
// The base glyph isn't covered, or the coverage
// index is too big. The latter means that the
// table is mal-formed...
return 0;
}
const BaseRecord *baseRecord = &baseArray->baseRecordArray[baseCoverage * mcCount];
Offset anchorTableOffset = SWAPW(baseRecord->baseAnchorTableOffsetArray[markClass]);
const AnchorTable *anchorTable = (const AnchorTable *) ((char *) baseArray + anchorTableOffset);
LEPoint baseAnchor, markAdvance, pixels;
anchorTable->getAnchor(baseGlyph, fontInstance, baseAnchor);
fontInstance->getGlyphAdvance(markGlyph, pixels);
fontInstance->pixelsToUnits(pixels, markAdvance);
float anchorDiffX = baseAnchor.fX - markAnchor.fX;
float anchorDiffY = baseAnchor.fY - markAnchor.fY;
if (glyphIterator->isRightToLeft()) {
float adjustX = markAdvance.fX + anchorDiffX;
glyphIterator->adjustCurrGlyphPositionAdjustment(anchorDiffX, -anchorDiffY, -adjustX, anchorDiffY);
} else {
LEPoint baseAdvance;
fontInstance->getGlyphAdvance(baseGlyph, pixels);
fontInstance->pixelsToUnits(pixels, baseAdvance);
float adjustX = baseAdvance.fX - anchorDiffX;
float advAdjustX = adjustX - markAdvance.fX;
glyphIterator->adjustCurrGlyphPositionAdjustment(-adjustX, -anchorDiffY, advAdjustX, anchorDiffY);
}
return 1;
}