icuSources/layout/Features.cpp

   1 /*
   2  * @(#)Features.cpp 1.4 00/03/15
   3  *
   4  * (C) Copyright IBM Corp. 1998-2003 - All Rights Reserved
   5  *
   6  */
   7
   8 #include "LETypes.h"
   9 #include "OpenTypeUtilities.h"
  10 #include "OpenTypeTables.h"
  11 #include "Features.h"
  12 #include "LESwaps.h"
  13
  14 U_NAMESPACE_BEGIN
  15
  16 const FeatureTable *FeatureListTable::getFeatureTable(le_uint16 featureIndex, LETag *featureTag) const
  17 {
  18     if (featureIndex >= SWAPW(featureCount)) {
  19         return 0;
  20     }
  21
  22     Offset featureTableOffset = featureRecordArray[featureIndex].featureTableOffset;
  23
  24     *featureTag = SWAPT(featureRecordArray[featureIndex].featureTag);
  25
  26     return (const FeatureTable *) ((char *) this + SWAPW(featureTableOffset));
  27 }
  28
  29 /*
  30  * Note: according to the OpenType Spec. v 1.4, the entries in the Feature
  31  * List Table are sorted alphabetically by feature tag; however, there seem
  32  * to be some fonts which have an unsorted list; that's why the binary search
  33  * is #if 0'd out and replaced by a linear search.
  34  *
  35  * Also note: as of ICU 2.6, this method isn't called anyhow...
  36  */
  37 const FeatureTable *FeatureListTable::getFeatureTable(LETag featureTag) const
  38 {
  39 #if 0
  40     Offset featureTableOffset =
  41         OpenTypeUtilities::getTagOffset(featureTag, (TagAndOffsetRecord *) featureRecordArray, SWAPW(featureCount));
  42
  43     if (featureTableOffset == 0) {
  44         return 0;
  45     }
  46
  47     return (const FeatureTable *) ((char *) this + SWAPW(featureTableOffset));
  48 #else
  49     int count = SWAPW(featureCount);
  50
  51     for (int i = 0; i < count; i += 1) {
  52         if (SWAPT(featureRecordArray[i].featureTag) == featureTag) {
  53             return (const FeatureTable *) ((char *) this + SWAPW(featureRecordArray[i].featureTableOffset));
  54         }
  55     }
  56
  57     return 0;
  58 #endif
  59 }
  60
  61 U_NAMESPACE_END