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/*
*
* (C) Copyright IBM Corp. 1998-2008 - All Rights Reserved
*
*/
#include "LETypes.h"
#include "LayoutEngine.h"
#include "ThaiLayoutEngine.h"
#include "ScriptAndLanguageTags.h"
#include "LEGlyphStorage.h"
#include "KernTable.h"
#include "ThaiShaping.h"
U_NAMESPACE_BEGIN
UOBJECT_DEFINE_RTTI_IMPLEMENTATION(ThaiLayoutEngine)
ThaiLayoutEngine::ThaiLayoutEngine(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode, le_int32 typoFlags, LEErrorCode &success)
: LayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, success)
{
fErrorChar = 0x25CC;
// Figure out which presentation forms the font uses
if (! fontInstance->canDisplay(0x0E01)) {
// No Thai in font; don't use presentation forms.
fGlyphSet = 3;
} else if (fontInstance->canDisplay(0x0E64)) {
// WorldType uses reserved space in Thai block
fGlyphSet = 0;
} else if (fontInstance->canDisplay(0xF701)) {
// Microsoft corporate zone
fGlyphSet = 1;
if (!fontInstance->canDisplay(fErrorChar)) {
fErrorChar = 0xF71B;
}
} else if (fontInstance->canDisplay(0xF885)) {
// Apple corporate zone
fGlyphSet = 2;
} else {
// no presentation forms in the font
fGlyphSet = 3;
}
}
ThaiLayoutEngine::~ThaiLayoutEngine()
{
// nothing to do
}
// Input: characters (0..max provided for context)
// Output: glyphs, char indices
// Returns: the glyph count
// NOTE: this assumes that ThaiShaping::compose will allocate the outChars array...
le_int32 ThaiLayoutEngine::computeGlyphs(const LEUnicode chars[], le_int32 offset, le_int32 count, le_int32 max, le_bool /*rightToLeft*/, LEGlyphStorage &glyphStorage, LEErrorCode &success)
{
if (LE_FAILURE(success)) {
return 0;
}
if (chars == NULL || offset < 0 || count < 0 || max < 0 || offset >= max || offset + count > max) {
success = LE_ILLEGAL_ARGUMENT_ERROR;
return 0;
}
LEUnicode *outChars;
le_int32 glyphCount;
// This is enough room for the worst-case expansion
// (it says here...)
outChars = LE_NEW_ARRAY(LEUnicode, count * 2);
if (outChars == NULL) {
success = LE_MEMORY_ALLOCATION_ERROR;
return 0;
}
glyphStorage.allocateGlyphArray(count * 2, FALSE, success);
if (LE_FAILURE(success)) {
LE_DELETE_ARRAY(outChars);
success = LE_MEMORY_ALLOCATION_ERROR;
return 0;
}
glyphCount = ThaiShaping::compose(chars, offset, count, fGlyphSet, fErrorChar, outChars, glyphStorage);
mapCharsToGlyphs(outChars, 0, glyphCount, FALSE, FALSE, glyphStorage, success);
LE_DELETE_ARRAY(outChars);
glyphStorage.adoptGlyphCount(glyphCount);
return glyphCount;
}
// This is the same as LayoutEngline::adjustGlyphPositions() except that it doesn't call adjustMarkGlyphs
void ThaiLayoutEngine::adjustGlyphPositions(const LEUnicode chars[], le_int32 offset, le_int32 count, le_bool /*reverse*/,
LEGlyphStorage &glyphStorage, LEErrorCode &success)
{
if (LE_FAILURE(success)) {
return;
}
if (chars == NULL || offset < 0 || count < 0) {
success = LE_ILLEGAL_ARGUMENT_ERROR;
return;
}
if (fTypoFlags & 0x1) { /* kerning enabled */
static const le_uint32 kernTableTag = LE_KERN_TABLE_TAG;
KernTable kt(fFontInstance, getFontTable(kernTableTag));
kt.process(glyphStorage);
}
// default is no adjustments
return;
}
U_NAMESPACE_END