scuffed-code/icu4c/source/layout/LayoutEngine.cpp

535 lines
14 KiB
C++

/*
* %W% %E%
*
* (C) Copyright IBM Corp. 1998-2003 - All Rights Reserved
*
*/
#include "LETypes.h"
#include "LEScripts.h"
#include "LELanguages.h"
#include "LayoutEngine.h"
#include "ArabicLayoutEngine.h"
#include "HanLayoutEngine.h"
#include "IndicLayoutEngine.h"
#include "ThaiLayoutEngine.h"
#include "GXLayoutEngine.h"
#include "ScriptAndLanguageTags.h"
#include "OpenTypeUtilities.h"
#include "GlyphSubstitutionTables.h"
#include "MorphTables.h"
#include "DefaultCharMapper.h"
U_NAMESPACE_BEGIN
#define ARRAY_SIZE(array) (sizeof array / sizeof array[0])
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 = ARRAY_SIZE(controlChars);
const LEUnicode32 DefaultCharMapper::mirroredChars[] = {
0x0028, 0x0029, // ascii paired punctuation
0x003c, 0x003e,
0x005b, 0x005d,
0x007b, 0x007d,
0x2045, 0x2046, // math symbols (not complete)
0x207d, 0x207e,
0x208d, 0x208e,
0x2264, 0x2265,
0x3008, 0x3009, // chinese paired punctuation
0x300a, 0x300b,
0x300c, 0x300d,
0x300e, 0x300f,
0x3010, 0x3011,
0x3014, 0x3015,
0x3016, 0x3017,
0x3018, 0x3019,
0x301a, 0x301b
};
const le_int32 DefaultCharMapper::mirroredCharsCount = ARRAY_SIZE(mirroredChars);
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 *)mirroredChars, mirroredCharsCount);
if (mirroredChars[index] == ch) {
le_int32 mirrorOffset = ((index & 1) == 0) ? 1 : -1;
return mirroredChars[index + mirrorOffset];
}
}
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
}
const char LayoutEngine::fgClassID=0;
LayoutEngine::LayoutEngine(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode)
: fGlyphCount(0), fGlyphs(NULL), fCharIndices(NULL), fPositions(NULL),
fFontInstance(fontInstance), fScriptCode(scriptCode), fLanguageCode(languageCode)
{
// nothing else to do?
}
void LayoutEngine::getCharIndices(le_int32 charIndices[], le_int32 indexBase, LEErrorCode &success) const
{
le_int32 i;
if LE_FAILURE(success) {
return;
}
if (charIndices == NULL) {
success = LE_ILLEGAL_ARGUMENT_ERROR;
return;
}
if (fCharIndices == NULL) {
success = LE_NO_LAYOUT_ERROR;
return;
}
for (i = 0; i < fGlyphCount; i += 1) {
charIndices[i] = fCharIndices[i] + indexBase;
}
}
void LayoutEngine::getCharIndices(le_int32 charIndices[], LEErrorCode &success) const
{
if LE_FAILURE(success) {
return;
}
if (charIndices == NULL) {
success = LE_ILLEGAL_ARGUMENT_ERROR;
return;
}
if (fCharIndices == NULL) {
success = LE_NO_LAYOUT_ERROR;
return;
}
LE_ARRAY_COPY(charIndices, fCharIndices, fGlyphCount);
}
// 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
{
le_int32 i;
if (LE_FAILURE(success)) {
return;
}
if (glyphs == NULL) {
success = LE_ILLEGAL_ARGUMENT_ERROR;
return;
}
if (fGlyphs == NULL) {
success = LE_NO_LAYOUT_ERROR;
return;
}
for (i = 0; i < fGlyphCount; i += 1) {
glyphs[i] = fGlyphs[i] | extraBits;
}
}
void LayoutEngine::getGlyphs(LEGlyphID glyphs[], LEErrorCode &success) const
{
if (LE_FAILURE(success)) {
return;
}
if (glyphs == NULL) {
success = LE_ILLEGAL_ARGUMENT_ERROR;
return;
}
if (fGlyphs == NULL) {
success = LE_NO_LAYOUT_ERROR;
return;
}
LE_ARRAY_COPY(glyphs, fGlyphs, fGlyphCount);
}
void LayoutEngine::getGlyphPositions(float positions[], LEErrorCode &success) const
{
if LE_FAILURE(success) {
return;
}
if (positions == NULL) {
success = LE_ILLEGAL_ARGUMENT_ERROR;
return;
}
if (fPositions == NULL) {
success = LE_NO_LAYOUT_ERROR;
return;
}
LE_ARRAY_COPY(positions, fPositions, fGlyphCount * 2 + 2);
}
void LayoutEngine::getGlyphPosition(le_int32 glyphIndex, float &x, float &y, LEErrorCode &success) const
{
if (LE_FAILURE(success)) {
return;
}
if (glyphIndex > fGlyphCount) {
success = LE_INDEX_OUT_OF_BOUNDS_ERROR;
return;
}
if (fPositions == NULL) {
success = LE_NO_LAYOUT_ERROR;
return;
}
x = fPositions[glyphIndex * 2];
y = fPositions[glyphIndex * 2 + 1];
}
le_int32 LayoutEngine::computeGlyphs(const LEUnicode chars[], le_int32 offset, le_int32 count, le_int32 max, le_bool rightToLeft,
LEGlyphID *&glyphs, le_int32 *&charIndices, 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;
}
mapCharsToGlyphs(chars, offset, count, rightToLeft, rightToLeft, glyphs, charIndices, success);
return count;
}
// Input: glyphs
// Output: positions
void LayoutEngine::positionGlyphs(const LEGlyphID glyphs[], le_int32 glyphCount, float x, float y, float *&positions, LEErrorCode &success)
{
if (LE_FAILURE(success)) {
return;
}
if (glyphCount < 0) {
success = LE_ILLEGAL_ARGUMENT_ERROR;
return;
}
if (positions == NULL) {
positions = LE_NEW_ARRAY(float, 2 * (glyphCount + 1));
if (positions == NULL) {
success = LE_MEMORY_ALLOCATION_ERROR;
return;
}
}
le_int32 i;
for (i = 0; i < glyphCount; i += 1) {
LEPoint advance;
positions[i * 2] = x;
positions[i * 2 + 1] = y;
fFontInstance->getGlyphAdvance(glyphs[i], advance);
x += advance.fX;
y += advance.fY;
}
positions[glyphCount * 2] = x;
positions[glyphCount * 2 + 1] = y;
}
void LayoutEngine::adjustGlyphPositions(const LEUnicode chars[], le_int32 offset, le_int32 count, le_bool /*reverse*/, LEGlyphID glyphs[], le_int32 glyphCount, float positions[], LEErrorCode &success)
{
if (LE_FAILURE(success)) {
return;
}
if (chars == NULL || glyphs == NULL || positions == NULL || offset < 0 || count < 0 || glyphCount < 0) {
success = LE_ILLEGAL_ARGUMENT_ERROR;
return;
}
// default is no adjustments
return;
}
void LayoutEngine::adjustMarkGlyphs(const LEGlyphID glyphs[], le_int32 glyphCount, le_bool reverse, LEGlyphFilter *markFilter,
float positions[], LEErrorCode &success)
{
float xAdjust = 0;
le_int32 g = 0, direction = 1;
le_int32 p;
if (LE_FAILURE(success)) {
return;
}
if (positions == NULL || markFilter == NULL) {
success = LE_ILLEGAL_ARGUMENT_ERROR;
return;
}
if (reverse) {
g = glyphCount - 1;
direction = -1;
}
for (p = 0; p < glyphCount; p += 1, g += direction) {
float xAdvance = positions[(p + 1) * 2] - positions[p * 2];
positions[p * 2] += xAdjust;
if (markFilter->accept(glyphs[g])) {
xAdjust -= xAdvance;
}
}
positions[glyphCount * 2] += xAdjust;
}
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,
LEGlyphID *&glyphs, le_int32 *&charIndices, LEErrorCode &success)
{
if (LE_FAILURE(success)) {
return;
}
if (chars == NULL || offset < 0 || count < 0) {
success = LE_ILLEGAL_ARGUMENT_ERROR;
return;
}
if (glyphs == NULL) {
glyphs = LE_NEW_ARRAY(LEGlyphID, count);
if (glyphs == NULL) {
success = LE_MEMORY_ALLOCATION_ERROR;
return;
}
}
if (charIndices == NULL) {
le_int32 i, dir = 1, out = 0;
if (reverse) {
out = count - 1;
dir = -1;
}
charIndices = LE_NEW_ARRAY(le_int32, count);
if (charIndices == NULL) {
success = LE_MEMORY_ALLOCATION_ERROR;
return;
}
for (i = 0; i < count; i += 1, out += dir) {
charIndices[out] = i;
}
}
DefaultCharMapper charMapper(TRUE, mirror);
fFontInstance->mapCharsToGlyphs(chars, offset, count, reverse, &charMapper, glyphs);
}
// 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;
}
fGlyphCount = computeGlyphs(chars, offset, count, max, rightToLeft, fGlyphs, fCharIndices, success);
positionGlyphs(fGlyphs, fGlyphCount, x, y, fPositions, success);
adjustGlyphPositions(chars, offset, count, rightToLeft, fGlyphs, fGlyphCount, fPositions, success);
return fGlyphCount;
}
void LayoutEngine::reset()
{
fGlyphCount = 0;
if (fGlyphs != NULL) {
LE_DELETE_ARRAY(fGlyphs);
fGlyphs = NULL;
}
if (fCharIndices != NULL) {
LE_DELETE_ARRAY(fCharIndices);
fCharIndices = NULL;
}
if (fPositions != NULL) {
LE_DELETE_ARRAY(fPositions);
fPositions = NULL;
}
}
LayoutEngine *LayoutEngine::layoutEngineFactory(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode, LEErrorCode &success)
{
static le_uint32 gsubTableTag = LE_GSUB_TABLE_TAG;
static 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:
result = new IndicOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, gsubTable);
break;
case arabScriptCode:
result = new ArabicOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, 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, gsubTable);
break;
}
// note: falling through to default case.
default:
result = new OpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, gsubTable);
break;
}
break;
default:
result = new OpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, 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:
{
result = new IndicOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode);
break;
}
case arabScriptCode:
case hebrScriptCode:
result = new UnicodeArabicOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode);
break;
//case hebrScriptCode:
// return new HebrewOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode);
case thaiScriptCode:
result = new ThaiLayoutEngine(fontInstance, scriptCode, languageCode);
break;
default:
result = new LayoutEngine(fontInstance, scriptCode, languageCode);
break;
}
}
}
if (result == NULL) {
success = LE_MEMORY_ALLOCATION_ERROR;
}
return result;
}
LayoutEngine::~LayoutEngine() {
reset();
}
U_NAMESPACE_END