icuSources/test/letest/cmaps.cpp

   1 /***************************************************************************
   2 *
   3 *   Copyright (C) 1998-2014, International Business Machines
   4 *   Corporation and others.  All Rights Reserved.
   5 *
   6 ************************************************************************/
   7
   8 #include "layout/LETypes.h"
   9 #include "layout/LESwaps.h"
  10
  11 #include "sfnt.h"
  12 #include "cmaps.h"
  13 #include <stdio.h>
  14
  15 #define SWAPU16(code) ((LEUnicode16) SWAPW(code))
  16 #define SWAPU32(code) ((LEUnicode32) SWAPL(code))
  17
  18 //
  19 // Finds the high bit by binary searching
  20 // through the bits in value.
  21 //
  22 le_int8 highBit(le_uint32 value)
  23 {
  24     le_uint8 bit = 0;
  25
  26     if (value >= 1 << 16) {
  27         value >>= 16;
  28         bit += 16;
  29     }
  30
  31     if (value >= 1 << 8) {
  32         value >>= 8;
  33         bit += 8;
  34     }
  35
  36     if (value >= 1 << 4) {
  37         value >>= 4;
  38         bit += 4;
  39     }
  40
  41     if (value >= 1 << 2) {
  42         value >>= 2;
  43         bit += 2;
  44     }
  45
  46     if (value >= 1 << 1) {
  47         value >>= 1;
  48         bit += 1;
  49     }
  50
  51     return bit;
  52 }
  53
  54 CMAPMapper *CMAPMapper::createUnicodeMapper(const CMAPTable *cmap)
  55 {
  56     le_uint16 i;
  57     le_uint16 nSubtables = SWAPW(cmap->numberSubtables);
  58     const CMAPEncodingSubtable *subtable = NULL;
  59     le_bool found = FALSE;
  60     le_uint16 foundPlatformID = 0xFFFF;
  61     le_uint16 foundPlatformSpecificID = 0xFFFF;
  62     le_uint32 foundOffset = 0;
  63     le_uint16 foundTable = 0xFFFF;
  64     // first pass, look for MS table. (preferred?)
  65     for (i = 0; i < nSubtables && !found; i += 1) {
  66         const CMAPEncodingSubtableHeader *esh = &cmap->encodingSubtableHeaders[i];
  67
  68         le_uint16 platformID = SWAPW(esh->platformID);
  69         le_uint16 platformSpecificID = SWAPW(esh->platformSpecificID);
  70         if (platformID == 3) { // microsoft
  71           switch (platformSpecificID) {
  72             case 1: // Unicode BMP (UCS-2)
  73             case 10: // Unicode UCS-4
  74                 foundOffset = SWAPL(esh->encodingOffset);
  75                 foundPlatformID = platformID;
  76                 foundPlatformSpecificID = platformSpecificID;
  77                 found = TRUE;
  78                 foundTable = i;
  79                 break;
  80
  81                 //default:
  82               //              printf("%s:%d: microsoft (3) platform specific ID %d (wanted 1 or 10) for subtable %d/%d\n", __FILE__, __LINE__, (SWAPW(esh->platformSpecificID)), i, nSubtables);
  83             }
  84         } else {
  85           //printf("%s:%d: platform  ID %d (wanted 3, microsoft) for subtable %d/%d\n", __FILE__, __LINE__, (SWAPW(esh->platformID)), i, nSubtables);
  86         }
  87     }
  88
  89     // second pass, allow non MS table
  90     // first pass, look for MS table. (preferred?)
  91       for (i = 0; i < nSubtables && !found; i += 1) {
  92         const CMAPEncodingSubtableHeader *esh = &cmap->encodingSubtableHeaders[i];
  93         le_uint16 platformID = SWAPW(esh->platformID);
  94         le_uint16 platformSpecificID = SWAPW(esh->platformSpecificID);
  95         //printf("%s:%d: table %d/%d has platform:specific %d:%d\n", __FILE__, __LINE__, i, nSubtables, platformID, platformSpecificID);
  96         switch(platformID) {
  97         case 0: // Unicode platform
  98           switch(platformSpecificID) {
  99           case 0:
 100           case 1:
 101           case 2:
 102           case 3:
 103             foundOffset = SWAPL(esh->encodingOffset);
 104             foundPlatformID = platformID;
 105             foundPlatformSpecificID = platformSpecificID;
 106             foundTable = i;
 107             found = TRUE;
 108             break;
 109
 110           default: printf("Error: table %d (psid %d) is unknown. Skipping.\n", i, platformSpecificID); break;
 111           }
 112           break;
 113
 114           //default:
 115           //printf("Skipping platform id %d\n", platformID);
 116         }
 117     }
 118
 119
 120     if (found)
 121     {
 122       subtable = (const CMAPEncodingSubtable *) ((const char *) cmap + foundOffset);
 123       //printf("%s:%d: using subtable #%d/%d type %d:%d\n", __FILE__, __LINE__, foundTable, nSubtables, foundPlatformID, foundPlatformSpecificID);
 124       (void)foundPlatformID;   // Suppress unused variable compiler warnings.
 125       (void)foundTable;
 126       (void)foundPlatformSpecificID;
 127     } else {
 128       printf("%s:%d: could not find subtable.\n", __FILE__, __LINE__);
 129       return NULL;
 130     }
 131
 132     le_uint16 tableFormat = SWAPW(subtable->format);
 133     //printf("%s:%d: table format %d\n", __FILE__, __LINE__, tableFormat);
 134
 135     switch (tableFormat) {
 136     case 4:
 137         return new CMAPFormat4Mapper(cmap, (const CMAPFormat4Encoding *) subtable);
 138
 139     case 12:
 140     {
 141         const CMAPFormat12Encoding *encoding = (const CMAPFormat12Encoding *) subtable;
 142
 143         return new CMAPGroupMapper(cmap, encoding->groups, SWAPL(encoding->nGroups));
 144     }
 145
 146     default:
 147         break;
 148     }
 149
 150     printf("%s:%d: Unknown format %x.\n", __FILE__, __LINE__, (SWAPW(subtable->format)));
 151     return NULL;
 152 }
 153
 154 CMAPFormat4Mapper::CMAPFormat4Mapper(const CMAPTable *cmap, const CMAPFormat4Encoding *header)
 155     : CMAPMapper(cmap)
 156 {
 157     le_uint16 segCount = SWAPW(header->segCountX2) / 2;
 158
 159     fEntrySelector = SWAPW(header->entrySelector);
 160     fRangeShift = SWAPW(header->rangeShift) / 2;
 161     fEndCodes = &header->endCodes[0];
 162     fStartCodes = &header->endCodes[segCount + 1]; // + 1 for reservedPad...
 163     fIdDelta = &fStartCodes[segCount];
 164     fIdRangeOffset = &fIdDelta[segCount];
 165 }
 166
 167 LEGlyphID CMAPFormat4Mapper::unicodeToGlyph(LEUnicode32 unicode32) const
 168 {
 169     if (unicode32 >= 0x10000) {
 170         return 0;
 171     }
 172
 173     LEUnicode16 unicode = (LEUnicode16) unicode32;
 174     le_uint16 index = 0;
 175     le_uint16 probe = 1 << fEntrySelector;
 176     TTGlyphID result = 0;
 177
 178     if (SWAPU16(fStartCodes[fRangeShift]) <= unicode) {
 179         index = fRangeShift;
 180     }
 181
 182     while (probe > (1 << 0)) {
 183         probe >>= 1;
 184
 185         if (SWAPU16(fStartCodes[index + probe]) <= unicode) {
 186             index += probe;
 187         }
 188     }
 189
 190     if (unicode >= SWAPU16(fStartCodes[index]) && unicode <= SWAPU16(fEndCodes[index])) {
 191         if (fIdRangeOffset[index] == 0) {
 192             result = (TTGlyphID) unicode;
 193         } else {
 194             le_uint16 offset = unicode - SWAPU16(fStartCodes[index]);
 195             le_uint16 rangeOffset = SWAPW(fIdRangeOffset[index]);
 196             le_uint16 *glyphIndexTable = (le_uint16 *) ((char *) &fIdRangeOffset[index] + rangeOffset);
 197
 198             result = SWAPW(glyphIndexTable[offset]);
 199         }
 200
 201         result += SWAPW(fIdDelta[index]);
 202     } else {
 203         result = 0;
 204     }
 205
 206     return LE_SET_GLYPH(0, result);
 207 }
 208
 209 CMAPFormat4Mapper::~CMAPFormat4Mapper()
 210 {
 211     // parent destructor does it all
 212 }
 213
 214 CMAPGroupMapper::CMAPGroupMapper(const CMAPTable *cmap, const CMAPGroup *groups, le_uint32 nGroups)
 215     : CMAPMapper(cmap), fGroups(groups)
 216 {
 217     le_uint8 bit = highBit(nGroups);
 218     fPower = 1 << bit;
 219     fRangeOffset = nGroups - fPower;
 220 }
 221
 222 LEGlyphID CMAPGroupMapper::unicodeToGlyph(LEUnicode32 unicode32) const
 223 {
 224     le_int32 probe = fPower;
 225     le_int32 range = 0;
 226
 227     if (SWAPU32(fGroups[fRangeOffset].startCharCode) <= unicode32) {
 228         range = fRangeOffset;
 229     }
 230
 231     while (probe > (1 << 0)) {
 232         probe >>= 1;
 233
 234         if (SWAPU32(fGroups[range + probe].startCharCode) <= unicode32) {
 235             range += probe;
 236         }
 237     }
 238
 239     if (SWAPU32(fGroups[range].startCharCode) <= unicode32 && SWAPU32(fGroups[range].endCharCode) >= unicode32) {
 240         return (LEGlyphID) (SWAPU32(fGroups[range].startGlyphCode) + unicode32 - SWAPU32(fGroups[range].startCharCode));
 241     }
 242
 243     return 0;
 244 }
 245
 246 CMAPGroupMapper::~CMAPGroupMapper()
 247 {
 248     // parent destructor does it all
 249 }
 250