icuSources/layout/Features.cpp

   1 /*
   2  * @(#)Features.cpp 1.4 00/03/15
   3  *
   4  * (C) Copyright IBM Corp. 1998-2015 - All Rights Reserved
   5  *
   6  */
   7
   8 #include "LETypes.h"
   9 #include "OpenTypeUtilities.h"
  10 #include "OpenTypeTables.h"
  11 #include "ICUFeatures.h"
  12 #include "LESwaps.h"
  13
  14 U_NAMESPACE_BEGIN
  15
  16 LEReferenceTo<FeatureTable> FeatureListTable::getFeatureTable(const LETableReference &base, le_uint16 featureIndex, LETag *featureTag, LEErrorCode &success) const
  17 {
  18     LEReferenceToArrayOf<FeatureRecord>
  19         featureRecordArrayRef(base, success, featureRecordArray, featureIndex+1);
  20
  21   if (featureIndex >= SWAPW(featureCount) || LE_FAILURE(success)) {
  22     return LEReferenceTo<FeatureTable>();
  23   }
  24
  25     Offset featureTableOffset = featureRecordArray[featureIndex].featureTableOffset;
  26
  27     *featureTag = SWAPT(featureRecordArray[featureIndex].featureTag);
  28
  29     return LEReferenceTo<FeatureTable>(base, success, SWAPW(featureTableOffset));
  30 }
  31
  32 #if 0
  33 /*
  34  * Note: according to the OpenType Spec. v 1.4, the entries in the Feature
  35  * List Table are sorted alphabetically by feature tag; however, there seem
  36  * to be some fonts which have an unsorted list; that's why the binary search
  37  * is #if 0'd out and replaced by a linear search.
  38  *
  39  * Also note: as of ICU 2.6, this method isn't called anyhow...
  40  */
  41 const FeatureTable *FeatureListTable::getFeatureTable(LETag featureTag) const
  42 {
  43 #if 0
  44     Offset featureTableOffset =
  45         OpenTypeUtilities::getTagOffset(featureTag, (TagAndOffsetRecord *) featureRecordArray, SWAPW(featureCount));
  46
  47     if (featureTableOffset == 0) {
  48         return 0;
  49     }
  50
  51     return (const FeatureTable *) ((char *) this + SWAPW(featureTableOffset));
  52 #else
  53     int count = SWAPW(featureCount);
  54
  55     for (int i = 0; i < count; i += 1) {
  56         if (SWAPT(featureRecordArray[i].featureTag) == featureTag) {
  57             return (const FeatureTable *) ((char *) this + SWAPW(featureRecordArray[i].featureTableOffset));
  58         }
  59     }
  60
  61     return 0;
  62 #endif
  63 }
  64 #endif
  65
  66 U_NAMESPACE_END