scuffed-code/icu4c/source/samples/layout/RenderingFontInstance.cpp
2002-03-19 18:45:51 +00:00

165 lines
4.5 KiB
C++

/*
*******************************************************************************
*
* Copyright (C) 1999-2001, International Business Machines
* Corporation and others. All Rights Reserved.
*
*******************************************************************************
* file name: RenderingFontInstance.cpp
*
* created on: 10/22/2001
* created by: Eric R. Mader
*/
#include "LETypes.h"
#include "LEFontInstance.h"
#include "RenderingFontInstance.h"
#include "LESwaps.h"
#include "sfnt.h"
#include "cmaps.h"
#include <string.h>
RenderingFontInstance::RenderingFontInstance(void *surface, le_int16 pointSize)
: fSurface(surface), fPointSize(pointSize), fUnitsPerEM(0), fAscent(0), fDescent(), fLeading(0),
fDeviceScaleX(1), fDeviceScaleY(1), fTableCache(NULL), fTableCacheCurr(0), fTableCacheSize(0), fMapper(NULL)
{
// we expect the subclass to call
// initMapper() and initFontTableCache
}
RenderingFontInstance::~RenderingFontInstance()
{
flushFontTableCache();
delete[] fTableCache;
delete fMapper;
}
void RenderingFontInstance::mapCharsToGlyphs(const LEUnicode chars[], le_int32 offset, le_int32 count,
le_bool reverse, const LECharMapper *mapper, LEGlyphID glyphs[]) const
{
le_int32 i, out = 0, dir = 1;
if (reverse) {
out = count - 1;
dir = -1;
}
for (i = offset; i < offset + count; i += 1, out += dir) {
LEUnicode16 high = chars[i];
LEUnicode32 code = high;
if (i < offset + count - 1 && high >= 0xD800 && high <= 0xDBFF) {
LEUnicode16 low = chars[i + 1];
if (low >= 0xDC00 && low <= 0xDFFF) {
code = (high - 0xD800) * 0x400 + low - 0xDC00 + 0x10000;
}
}
glyphs[out] = mapCharToGlyph(code, mapper);
if (code >= 0x10000) {
i += 1;
glyphs[out += dir] = 0xFFFF;
}
}
}
LEGlyphID RenderingFontInstance::mapCharToGlyph(LEUnicode32 ch, const LECharMapper *mapper) const
{
LEUnicode32 mappedChar = mapper->mapChar(ch);
if (mappedChar == 0xFFFE || mappedChar == 0xFFFF) {
return 0xFFFF;
}
if (mappedChar == 0x200C || mappedChar == 0x200D) {
return 1;
}
return fMapper->unicodeToGlyph(mappedChar);
}
const void *RenderingFontInstance::getFontTable(LETag tableTag) const
{
for (int i = 0; i < fTableCacheCurr; i += 1) {
if (fTableCache[i].tag == tableTag) {
return fTableCache[i].table;
}
}
RenderingFontInstance *realThis = (RenderingFontInstance *) this;
if (realThis->fTableCacheCurr >= realThis->fTableCacheSize) {
le_int32 newSize = realThis->fTableCacheSize + TABLE_CACHE_GROW;
TableCacheEntry *newTable = new TableCacheEntry[newSize];
// FIXME: need a better strategy than this...
if (newTable == NULL) {
return NULL;
}
memcpy(newTable, realThis->fTableCache, realThis->fTableCacheSize * sizeof realThis->fTableCache[0]);
delete[] realThis->fTableCache;
for (int i = realThis->fTableCacheSize; i < newSize; i += 1) {
newTable[i].tag = 0;
newTable[i].table = NULL;
}
realThis->fTableCache = newTable;
realThis->fTableCacheSize = newSize;
}
realThis->fTableCache[realThis->fTableCacheCurr].tag = tableTag;
realThis->fTableCache[realThis->fTableCacheCurr].table = (void *) realThis->readFontTable(tableTag);
return fTableCache[realThis->fTableCacheCurr++].table;
};
RFIErrorCode RenderingFontInstance::initMapper()
{
LETag cmapTag = 0x636D6170; // 'cmap'
const CMAPTable *cmap = (const CMAPTable *) readFontTable(cmapTag);
if (cmap == NULL) {
return RFI_MISSING_FONT_TABLE_ERROR;
}
fMapper = CMAPMapper::createUnicodeMapper(cmap);
if (fMapper == NULL) {
return RFI_MISSING_FONT_TABLE_ERROR;
}
return RFI_NO_ERROR;
}
RFIErrorCode RenderingFontInstance::initFontTableCache()
{
fTableCacheSize = TABLE_CACHE_INIT;
fTableCache = new TableCacheEntry[fTableCacheSize];
if (fTableCache == 0) {
return RFI_OUT_OF_MEMORY_ERROR;
}
for (int i = 0; i < fTableCacheSize; i += 1) {
fTableCache[i].tag = 0;
fTableCache[i].table = NULL;
}
return RFI_NO_ERROR;
}
void RenderingFontInstance::flushFontTableCache()
{
for (int i = fTableCacheCurr - 1; i >= 0; i -= 1) {
delete[] (char *) fTableCache[i].table;
}
fTableCacheCurr = 0;
}