sl@0: /***************************************************************************
sl@0: *
sl@0: *   Copyright (C) 1998-2002, International Business Machines
sl@0: *   Corporation and others.  All Rights Reserved.
sl@0: *
sl@0: ************************************************************************/
sl@0: 
sl@0: #include <stdio.h>
sl@0: 
sl@0: #include "LETypes.h"
sl@0: #include "FontObject.h"
sl@0: #include "LESwaps.h"
sl@0: 
sl@0: FontObject::FontObject(char *fileName)
sl@0:   : directory(NULL), numTables(0), searchRange(0),entrySelector(0),
sl@0:     cmapTable(NULL), cmSegCount(0), cmSearchRange(0), cmEntrySelector(0),
sl@0:     cmEndCodes(NULL), cmStartCodes(NULL), cmIdDelta(0), cmIdRangeOffset(0),
sl@0:     headTable(NULL), hmtxTable(NULL), numGlyphs(0), numOfLongHorMetrics(0), file(NULL)
sl@0: {
sl@0:     file = fopen(fileName, "rb");
sl@0: 
sl@0:     if (file == NULL) {
sl@0:         printf("?? Couldn't open %s", fileName);
sl@0:         return;
sl@0:     }
sl@0: 
sl@0:     SFNTDirectory tempDir;
sl@0: 
sl@0:     fread(&tempDir, sizeof tempDir, 1, file);
sl@0: 
sl@0:     numTables       = SWAPW(tempDir.numTables);
sl@0:     searchRange     = SWAPW(tempDir.searchRange) >> 4;
sl@0:     entrySelector   = SWAPW(tempDir.entrySelector);
sl@0:     rangeShift      = SWAPW(tempDir.rangeShift) >> 4;
sl@0: 
sl@0:     int dirSize = sizeof tempDir + ((numTables - ANY_NUMBER) * sizeof(DirectoryEntry));
sl@0: 
sl@0:     directory = (SFNTDirectory *) new char[dirSize];
sl@0: 
sl@0:     fseek(file, 0L, SEEK_SET);
sl@0:     fread(directory, sizeof(char), dirSize, file);
sl@0: 
sl@0:     initUnicodeCMAP();
sl@0: }
sl@0: 
sl@0: FontObject::~FontObject()
sl@0: {
sl@0:     fclose(file);
sl@0:     delete[] directory;
sl@0:     delete[] cmapTable;
sl@0:     delete[] headTable;
sl@0:     delete[] hmtxTable;
sl@0: }
sl@0: 
sl@0: void FontObject::deleteTable(void *table)
sl@0: {
sl@0:     delete[] (char *) table;
sl@0: }
sl@0: 
sl@0: DirectoryEntry *FontObject::findTable(LETag tag)
sl@0: {
sl@0:     le_uint16 table = 0;
sl@0:     le_uint16 probe = 1 << entrySelector;
sl@0: 
sl@0:     if (SWAPL(directory->tableDirectory[rangeShift].tag) <= tag) {
sl@0:         table = rangeShift;
sl@0:     }
sl@0: 
sl@0:     while (probe > (1 << 0)) {
sl@0:         probe >>= 1;
sl@0: 
sl@0:         if (SWAPL(directory->tableDirectory[table + probe].tag) <= tag) {
sl@0:             table += probe;
sl@0:         }
sl@0:     }
sl@0: 
sl@0:     if (SWAPL(directory->tableDirectory[table].tag) == tag) {
sl@0:         return &directory->tableDirectory[table];
sl@0:     }
sl@0: 
sl@0:     return NULL;
sl@0: }
sl@0: 
sl@0: void *FontObject::readTable(LETag tag, le_uint32 *length)
sl@0: {
sl@0:     DirectoryEntry *entry = findTable(tag);
sl@0: 
sl@0:     if (entry == NULL) {
sl@0:         *length = 0;
sl@0:         return NULL;
sl@0:     }
sl@0: 
sl@0:     *length = SWAPL(entry->length);
sl@0: 
sl@0:     void *table = new char[*length];
sl@0: 
sl@0:     fseek(file, SWAPL(entry->offset), SEEK_SET);
sl@0:     fread(table, sizeof(char), *length, file);
sl@0: 
sl@0:     return table;
sl@0: }
sl@0: 
sl@0: CMAPEncodingSubtable *FontObject::findCMAP(le_uint16 platformID, le_uint16 platformSpecificID)
sl@0: {
sl@0:     LETag cmapTag = 0x636D6170; // 'cmap'
sl@0: 
sl@0:     if (cmapTable == NULL) {
sl@0:         le_uint32 length;
sl@0: 
sl@0:         cmapTable = (CMAPTable *) readTable(cmapTag, &length);
sl@0:     }
sl@0: 
sl@0:     if (cmapTable != NULL) {
sl@0:         le_uint16 i;
sl@0:         le_uint16 nSubtables = SWAPW(cmapTable->numberSubtables);
sl@0: 
sl@0: 
sl@0:         for (i = 0; i < nSubtables; i += 1) {
sl@0:             CMAPEncodingSubtableHeader *esh = &cmapTable->encodingSubtableHeaders[i];
sl@0: 
sl@0:             if (SWAPW(esh->platformID) == platformID &&
sl@0:                 SWAPW(esh->platformSpecificID) == platformSpecificID) {
sl@0:                 return (CMAPEncodingSubtable *) ((char *) cmapTable + SWAPL(esh->encodingOffset));
sl@0:             }
sl@0:         }
sl@0:     }
sl@0: 
sl@0:     return NULL;
sl@0: }
sl@0: 
sl@0: void FontObject::initUnicodeCMAP()
sl@0: {
sl@0:     CMAPEncodingSubtable *encodingSubtable = findCMAP(3, 1);
sl@0: 
sl@0:     if (encodingSubtable == 0 ||
sl@0:         SWAPW(encodingSubtable->format) != 4) {
sl@0:         printf("Can't find unicode 'cmap'");
sl@0:         return;
sl@0:     }
sl@0: 
sl@0:     CMAPFormat4Encoding *header = (CMAPFormat4Encoding *) encodingSubtable;
sl@0: 
sl@0:     cmSegCount = SWAPW(header->segCountX2) / 2;
sl@0:     cmSearchRange = SWAPW(header->searchRange);
sl@0:     cmEntrySelector = SWAPW(header->entrySelector);
sl@0:     cmRangeShift = SWAPW(header->rangeShift) / 2;
sl@0:     cmEndCodes = &header->endCodes[0];
sl@0:     cmStartCodes = &header->endCodes[cmSegCount + 1]; // + 1 for reservedPad...
sl@0:     cmIdDelta = &cmStartCodes[cmSegCount];
sl@0:     cmIdRangeOffset = &cmIdDelta[cmSegCount];
sl@0: }
sl@0: 
sl@0: LEGlyphID FontObject::unicodeToGlyph(LEUnicode32 unicode32)
sl@0: {
sl@0:     if (unicode32 >= 0x10000) {
sl@0:         return 0;
sl@0:     }
sl@0: 
sl@0:     LEUnicode16 unicode = (LEUnicode16) unicode32;
sl@0:     le_uint16 index = 0;
sl@0:     le_uint16 probe = 1 << cmEntrySelector;
sl@0:     LEGlyphID result = 0;
sl@0: 
sl@0:     if (SWAPW(cmStartCodes[cmRangeShift]) <= unicode) {
sl@0:         index = cmRangeShift;
sl@0:     }
sl@0: 
sl@0:     while (probe > (1 << 0)) {
sl@0:         probe >>= 1;
sl@0: 
sl@0:         if (SWAPW(cmStartCodes[index + probe]) <= unicode) {
sl@0:             index += probe;
sl@0:         }
sl@0:     }
sl@0: 
sl@0:     if (unicode >= SWAPW(cmStartCodes[index]) && unicode <= SWAPW(cmEndCodes[index])) {
sl@0:         if (cmIdRangeOffset[index] == 0) {
sl@0:             result = (LEGlyphID) unicode;
sl@0:         } else {
sl@0:             le_uint16 offset = unicode - SWAPW(cmStartCodes[index]);
sl@0:             le_uint16 rangeOffset = SWAPW(cmIdRangeOffset[index]);
sl@0:             le_uint16 *glyphIndexTable = (le_uint16 *) ((char *) &cmIdRangeOffset[index] + rangeOffset);
sl@0: 
sl@0:             result = SWAPW(glyphIndexTable[offset]);
sl@0:         }
sl@0: 
sl@0:         result += SWAPW(cmIdDelta[index]);
sl@0:     } else {
sl@0:         result = 0;
sl@0:     }
sl@0: 
sl@0:     return result;
sl@0: }
sl@0: 
sl@0: le_uint16 FontObject::getUnitsPerEM()
sl@0: {
sl@0:     if (headTable == NULL) {
sl@0:         LETag headTag = 0x68656164; // 'head'
sl@0:         le_uint32 length;
sl@0: 
sl@0:         headTable = (HEADTable *) readTable(headTag, &length);
sl@0:     }
sl@0: 
sl@0:     return SWAPW(headTable->unitsPerEm);
sl@0: }
sl@0: 
sl@0: le_uint16 FontObject::getGlyphAdvance(LEGlyphID glyph)
sl@0: {
sl@0:     if (hmtxTable == NULL) {
sl@0:         LETag maxpTag = 0x6D617870; // 'maxp'
sl@0:         LETag hheaTag = 0x68686561; // 'hhea'
sl@0:         LETag hmtxTag = 0x686D7478; // 'hmtx'
sl@0:         le_uint32 length;
sl@0:         HHEATable *hheaTable;
sl@0:         MAXPTable *maxpTable = (MAXPTable *) readTable(maxpTag, &length);
sl@0: 
sl@0:         numGlyphs = SWAPW(maxpTable->numGlyphs);
sl@0:         deleteTable(maxpTable);
sl@0: 
sl@0:         hheaTable = (HHEATable *) readTable(hheaTag, &length);
sl@0:         numOfLongHorMetrics = SWAPW(hheaTable->numOfLongHorMetrics);
sl@0:         deleteTable(hheaTable);
sl@0: 
sl@0:         hmtxTable = (HMTXTable *) readTable(hmtxTag, &length);
sl@0:     }
sl@0: 
sl@0:     le_uint16 index = glyph;
sl@0: 
sl@0:     if (glyph >= numGlyphs) {
sl@0:         return 0;
sl@0:     }
sl@0: 
sl@0:     if (glyph >= numOfLongHorMetrics) {
sl@0:         index = numOfLongHorMetrics - 1;
sl@0:     }
sl@0: 
sl@0:     return SWAPW(hmtxTable->hMetrics[index].advanceWidth);
sl@0: }
sl@0: 
sl@0: