scuffed-code/icu4c/source/layout/LayoutEngine.cpp
2006-02-21 17:13:48 +00:00

557 lines
16 KiB
C++

/*
*
* (C) Copyright IBM Corp. 1998-2006 - All Rights Reserved
*
*/
#include "LETypes.h"
#include "LEScripts.h"
#include "LELanguages.h"
#include "LayoutEngine.h"
#include "ArabicLayoutEngine.h"
#include "CanonShaping.h"
#include "HanLayoutEngine.h"
#include "HangulLayoutEngine.h"
#include "IndicLayoutEngine.h"
#include "KhmerLayoutEngine.h"
#include "ThaiLayoutEngine.h"
#include "TibetanLayoutEngine.h"
#include "GXLayoutEngine.h"
#include "ScriptAndLanguageTags.h"
#include "CharSubstitutionFilter.h"
#include "LEGlyphStorage.h"
#include "OpenTypeUtilities.h"
#include "GlyphSubstitutionTables.h"
#include "MorphTables.h"
#include "DefaultCharMapper.h"
#include "KernTable.h"
U_NAMESPACE_BEGIN
const LEUnicode32 DefaultCharMapper::controlChars[] = {
0x0009, 0x000A, 0x000D,
/*0x200C, 0x200D,*/ 0x200E, 0x200F,
0x2028, 0x2029, 0x202A, 0x202B, 0x202C, 0x202D, 0x202E,
0x206A, 0x206B, 0x206C, 0x206D, 0x206E, 0x206F
};
const le_int32 DefaultCharMapper::controlCharsCount = LE_ARRAY_SIZE(controlChars);
LEUnicode32 DefaultCharMapper::mapChar(LEUnicode32 ch) const
{
if (fFilterControls) {
le_int32 index = OpenTypeUtilities::search((le_uint32)ch, (le_uint32 *)controlChars, controlCharsCount);
if (controlChars[index] == ch) {
return 0xFFFF;
}
}
if (fMirror) {
le_int32 index = OpenTypeUtilities::search((le_uint32) ch, (le_uint32 *)DefaultCharMapper::mirroredChars, DefaultCharMapper::mirroredCharsCount);
if (mirroredChars[index] == ch) {
return DefaultCharMapper::srahCderorrim[index];
}
}
return ch;
}
// This is here to get it out of LEGlyphFilter.h.
// No particular reason to put it here, other than
// this is a good central location...
LEGlyphFilter::~LEGlyphFilter()
{
// nothing to do
}
CharSubstitutionFilter::CharSubstitutionFilter(const LEFontInstance *fontInstance)
: fFontInstance(fontInstance)
{
// nothing to do
}
CharSubstitutionFilter::~CharSubstitutionFilter()
{
// nothing to do
}
UOBJECT_DEFINE_RTTI_IMPLEMENTATION(LayoutEngine)
#define ccmpFeatureTag LE_CCMP_FEATURE_TAG
#define ccmpFeatureMask 0x80000000UL
#define canonFeatures (ccmpFeatureMask)
static const FeatureMap canonFeatureMap[] =
{
{ccmpFeatureTag, ccmpFeatureMask}
};
static const le_int32 canonFeatureMapCount = LE_ARRAY_SIZE(canonFeatureMap);
LayoutEngine::LayoutEngine(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode, le_int32 typoFlags)
: fGlyphStorage(NULL), fFontInstance(fontInstance), fScriptCode(scriptCode), fLanguageCode(languageCode),
fTypoFlags(typoFlags)
{
fGlyphStorage = new LEGlyphStorage();
}
le_int32 LayoutEngine::getGlyphCount() const
{
return fGlyphStorage->getGlyphCount();
}
void LayoutEngine::getCharIndices(le_int32 charIndices[], le_int32 indexBase, LEErrorCode &success) const
{
fGlyphStorage->getCharIndices(charIndices, indexBase, success);
}
void LayoutEngine::getCharIndices(le_int32 charIndices[], LEErrorCode &success) const
{
fGlyphStorage->getCharIndices(charIndices, success);
}
// Copy the glyphs into caller's (32-bit) glyph array, OR in extraBits
void LayoutEngine::getGlyphs(le_uint32 glyphs[], le_uint32 extraBits, LEErrorCode &success) const
{
fGlyphStorage->getGlyphs(glyphs, extraBits, success);
}
void LayoutEngine::getGlyphs(LEGlyphID glyphs[], LEErrorCode &success) const
{
fGlyphStorage->getGlyphs(glyphs, success);
}
void LayoutEngine::getGlyphPositions(float positions[], LEErrorCode &success) const
{
fGlyphStorage->getGlyphPositions(positions, success);
}
void LayoutEngine::getGlyphPosition(le_int32 glyphIndex, float &x, float &y, LEErrorCode &success) const
{
fGlyphStorage->getGlyphPosition(glyphIndex, x, y, success);
}
le_int32 LayoutEngine::characterProcessing(const LEUnicode chars[], le_int32 offset, le_int32 count, le_int32 max, le_bool rightToLeft,
LEUnicode *&outChars, LEGlyphStorage &/*glyphStorage*/, LEErrorCode &success)
{
if (LE_FAILURE(success)) {
return 0;
}
if (offset < 0 || count < 0 || max < 0 || offset >= max || offset + count > max) {
success = LE_ILLEGAL_ARGUMENT_ERROR;
return 0;
}
const GlyphSubstitutionTableHeader *canonGSUBTable = (GlyphSubstitutionTableHeader *) CanonShaping::glyphSubstitutionTable;
LETag scriptTag = OpenTypeLayoutEngine::getScriptTag(fScriptCode);
LETag langSysTag = OpenTypeLayoutEngine::getLangSysTag(fLanguageCode);
le_int32 i, dir = 1, out = 0, outCharCount = count;
if (canonGSUBTable->coversScript(scriptTag)) {
CharSubstitutionFilter *substitutionFilter = new CharSubstitutionFilter(fFontInstance);
const LEUnicode *inChars = &chars[offset];
LEUnicode *reordered = NULL;
LEGlyphStorage fakeGlyphStorage;
fakeGlyphStorage.allocateGlyphArray(count, rightToLeft, success);
if (LE_FAILURE(success)) {
return 0;
}
// This is the cheapest way to get mark reordering only for Hebrew.
// We could just do the mark reordering for all scripts, but most
// of them probably don't need it...
if (fScriptCode == hebrScriptCode) {
reordered = LE_NEW_ARRAY(LEUnicode, count);
if (reordered == NULL) {
success = LE_MEMORY_ALLOCATION_ERROR;
return 0;
}
CanonShaping::reorderMarks(&chars[offset], count, rightToLeft, reordered, fakeGlyphStorage);
inChars = reordered;
}
fakeGlyphStorage.allocateAuxData(success);
if (LE_FAILURE(success)) {
return 0;
}
if (rightToLeft) {
out = count - 1;
dir = -1;
}
for (i = 0; i < count; i += 1, out += dir) {
fakeGlyphStorage[out] = (LEGlyphID) inChars[i];
fakeGlyphStorage.setAuxData(out, canonFeatures, success);
}
if (reordered != NULL) {
LE_DELETE_ARRAY(reordered);
}
outCharCount = canonGSUBTable->process(fakeGlyphStorage, rightToLeft, scriptTag, langSysTag, NULL, substitutionFilter, canonFeatureMap, canonFeatureMapCount, FALSE);
out = (rightToLeft? outCharCount - 1 : 0);
outChars = LE_NEW_ARRAY(LEUnicode, outCharCount);
for (i = 0; i < outCharCount; i += 1, out += dir) {
outChars[out] = (LEUnicode) LE_GET_GLYPH(fakeGlyphStorage[i]);
}
delete substitutionFilter;
}
return outCharCount;
}
le_int32 LayoutEngine::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 = NULL;
le_int32 outCharCount = characterProcessing(chars, offset, count, max, rightToLeft, outChars, glyphStorage, success);
if (outChars != NULL) {
mapCharsToGlyphs(outChars, 0, outCharCount, rightToLeft, rightToLeft, TRUE, glyphStorage, success);
LE_DELETE_ARRAY(outChars); // FIXME: a subclass may have allocated this, in which case this delete might not work...
} else {
mapCharsToGlyphs(chars, offset, count, rightToLeft, rightToLeft, TRUE, glyphStorage, success);
}
return glyphStorage.getGlyphCount();
}
// Input: glyphs
// Output: positions
void LayoutEngine::positionGlyphs(LEGlyphStorage &glyphStorage, float x, float y, LEErrorCode &success)
{
if (LE_FAILURE(success)) {
return;
}
glyphStorage.allocatePositions(success);
if (LE_FAILURE(success)) {
return;
}
le_int32 i, glyphCount = glyphStorage.getGlyphCount();
for (i = 0; i < glyphCount; i += 1) {
LEPoint advance;
glyphStorage.setPosition(i, x, y, success);
fFontInstance->getGlyphAdvance(glyphStorage[i], advance);
x += advance.fX;
y += advance.fY;
}
glyphStorage.setPosition(glyphCount, x, y, success);
}
void LayoutEngine::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;
}
void LayoutEngine::adjustMarkGlyphs(LEGlyphStorage &glyphStorage, LEGlyphFilter *markFilter, LEErrorCode &success)
{
float xAdjust = 0;
le_int32 p, glyphCount = glyphStorage.getGlyphCount();
if (LE_FAILURE(success)) {
return;
}
if (markFilter == NULL) {
success = LE_ILLEGAL_ARGUMENT_ERROR;
return;
}
float ignore, prev;
glyphStorage.getGlyphPosition(0, prev, ignore, success);
for (p = 0; p < glyphCount; p += 1) {
float next, xAdvance;
glyphStorage.getGlyphPosition(p + 1, next, ignore, success);
xAdvance = next - prev;
glyphStorage.adjustPosition(p, xAdjust, 0, success);
if (markFilter->accept(glyphStorage[p])) {
xAdjust -= xAdvance;
}
prev = next;
}
glyphStorage.adjustPosition(glyphCount, xAdjust, 0, success);
}
void LayoutEngine::adjustMarkGlyphs(const LEUnicode chars[], le_int32 charCount, le_bool reverse, LEGlyphStorage &glyphStorage, LEGlyphFilter *markFilter, LEErrorCode &success)
{
float xAdjust = 0;
le_int32 c = 0, direction = 1, p;
le_int32 glyphCount = glyphStorage.getGlyphCount();
if (LE_FAILURE(success)) {
return;
}
if (markFilter == NULL) {
success = LE_ILLEGAL_ARGUMENT_ERROR;
return;
}
if (reverse) {
c = glyphCount - 1;
direction = -1;
}
float ignore, prev;
glyphStorage.getGlyphPosition(0, prev, ignore, success);
for (p = 0; p < charCount; p += 1, c += direction) {
float next, xAdvance;
glyphStorage.getGlyphPosition(p + 1, next, ignore, success);
xAdvance = next - prev;
glyphStorage.adjustPosition(p, xAdjust, 0, success);
if (markFilter->accept(chars[c])) {
xAdjust -= xAdvance;
}
prev = next;
}
glyphStorage.adjustPosition(glyphCount, xAdjust, 0, success);
}
const void *LayoutEngine::getFontTable(LETag tableTag) const
{
return fFontInstance->getFontTable(tableTag);
}
void LayoutEngine::mapCharsToGlyphs(const LEUnicode chars[], le_int32 offset, le_int32 count, le_bool reverse, le_bool mirror, le_bool filterZeroWidth,
LEGlyphStorage &glyphStorage, LEErrorCode &success)
{
if (LE_FAILURE(success)) {
return;
}
glyphStorage.allocateGlyphArray(count, reverse, success);
DefaultCharMapper charMapper(TRUE, mirror);
fFontInstance->mapCharsToGlyphs(chars, offset, count, reverse, &charMapper, filterZeroWidth, glyphStorage);
}
// Input: characters, font?
// Output: glyphs, positions, char indices
// Returns: number of glyphs
le_int32 LayoutEngine::layoutChars(const LEUnicode chars[], le_int32 offset, le_int32 count, le_int32 max, le_bool rightToLeft,
float x, float y, 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;
}
le_int32 glyphCount;
glyphCount = computeGlyphs(chars, offset, count, max, rightToLeft, *fGlyphStorage, success);
positionGlyphs(*fGlyphStorage, x, y, success);
adjustGlyphPositions(chars, offset, count, rightToLeft, *fGlyphStorage, success);
return glyphCount;
}
void LayoutEngine::reset()
{
fGlyphStorage->reset();
}
LayoutEngine *LayoutEngine::layoutEngineFactory(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode, LEErrorCode &success)
{
// 3 -> kerning and ligatures
return LayoutEngine::layoutEngineFactory(fontInstance, scriptCode, languageCode, 3, success);
}
LayoutEngine *LayoutEngine::layoutEngineFactory(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode, le_int32 typoFlags, LEErrorCode &success)
{
static const le_uint32 gsubTableTag = LE_GSUB_TABLE_TAG;
static const le_uint32 mortTableTag = LE_MORT_TABLE_TAG;
if (LE_FAILURE(success)) {
return NULL;
}
const GlyphSubstitutionTableHeader *gsubTable = (const GlyphSubstitutionTableHeader *) fontInstance->getFontTable(gsubTableTag);
LayoutEngine *result = NULL;
LETag scriptTag = 0x00000000;
LETag languageTag = 0x00000000;
if (gsubTable != NULL && gsubTable->coversScript(scriptTag = OpenTypeLayoutEngine::getScriptTag(scriptCode))) {
switch (scriptCode) {
case bengScriptCode:
case devaScriptCode:
case gujrScriptCode:
case kndaScriptCode:
case mlymScriptCode:
case oryaScriptCode:
case guruScriptCode:
case tamlScriptCode:
case teluScriptCode:
case sinhScriptCode:
result = new IndicOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, gsubTable);
break;
case arabScriptCode:
result = new ArabicOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, gsubTable);
break;
case hangScriptCode:
result = new HangulOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, gsubTable);
break;
case haniScriptCode:
languageTag = OpenTypeLayoutEngine::getLangSysTag(languageCode);
switch (languageCode) {
case korLanguageCode:
case janLanguageCode:
case zhtLanguageCode:
case zhsLanguageCode:
if (gsubTable->coversScriptAndLanguage(scriptTag, languageTag, TRUE)) {
result = new HanOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, gsubTable);
break;
}
// note: falling through to default case.
default:
result = new OpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, gsubTable);
break;
}
break;
case tibtScriptCode:
result = new TibetanOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, gsubTable);
break;
case khmrScriptCode:
result = new KhmerOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, gsubTable);
break;
default:
result = new OpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, gsubTable);
break;
}
} else {
const MorphTableHeader *morphTable = (MorphTableHeader *) fontInstance->getFontTable(mortTableTag);
if (morphTable != NULL) {
result = new GXLayoutEngine(fontInstance, scriptCode, languageCode, morphTable);
} else {
switch (scriptCode) {
case bengScriptCode:
case devaScriptCode:
case gujrScriptCode:
case kndaScriptCode:
case mlymScriptCode:
case oryaScriptCode:
case guruScriptCode:
case tamlScriptCode:
case teluScriptCode:
case sinhScriptCode:
{
result = new IndicOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags);
break;
}
case arabScriptCode:
//case hebrScriptCode:
result = new UnicodeArabicOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags);
break;
//case hebrScriptCode:
// return new HebrewOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags);
case thaiScriptCode:
result = new ThaiLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags);
break;
default:
result = new LayoutEngine(fontInstance, scriptCode, languageCode, typoFlags);
break;
}
}
}
if (result == NULL) {
success = LE_MEMORY_ALLOCATION_ERROR;
}
return result;
}
LayoutEngine::~LayoutEngine() {
delete fGlyphStorage;
}
U_NAMESPACE_END