icuSources/layout/TibetanLayoutEngine.cpp

   1 /*
   2  *
   3  * (C) Copyright IBM Corp. 1998-2008 - All Rights Reserved
   4  *
   5  * Developed at DIT - Government of Bhutan
   6  *
   7  * Contact person: Pema Geyleg - <pema_geyleg@druknet.bt>
   8  *
   9  * This file is a modification of the ICU file KhmerReordering.cpp
  10  * by Jens Herden and Javier Sola who have given all their possible rights to IBM and the Governement of Bhutan
  11  * A first module for Dzongkha was developed by Karunakar under Panlocalisation funding.
  12  * Assistance for this module has been received from Namgay Thinley, Christopher Fynn and Javier Sola
  13  *
  14  */
  15
  16
  17 #include "OpenTypeLayoutEngine.h"
  18 #include "TibetanLayoutEngine.h"
  19 #include "LEGlyphStorage.h"
  20 #include "TibetanReordering.h"
  21
  22 U_NAMESPACE_BEGIN
  23
  24 UOBJECT_DEFINE_RTTI_IMPLEMENTATION(TibetanOpenTypeLayoutEngine)
  25
  26 TibetanOpenTypeLayoutEngine::TibetanOpenTypeLayoutEngine(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode,
  27                     le_int32 typoFlags, const GlyphSubstitutionTableHeader *gsubTable, LEErrorCode &success)
  28     : OpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, gsubTable, success)
  29 {
  30     fFeatureMap   = TibetanReordering::getFeatureMap(fFeatureMapCount);
  31     fFeatureOrder = TRUE;
  32 }
  33
  34 TibetanOpenTypeLayoutEngine::TibetanOpenTypeLayoutEngine(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode,
  35                                                      le_int32 typoFlags, LEErrorCode &success)
  36     : OpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, success)
  37 {
  38     fFeatureMap   = TibetanReordering::getFeatureMap(fFeatureMapCount);
  39     fFeatureOrder = TRUE;
  40 }
  41
  42 TibetanOpenTypeLayoutEngine::~TibetanOpenTypeLayoutEngine()
  43 {
  44     // nothing to do
  45 }
  46
  47 // Input: characters
  48 // Output: characters, char indices, tags
  49 // Returns: output character count
  50 le_int32 TibetanOpenTypeLayoutEngine::characterProcessing(const LEUnicode chars[], le_int32 offset, le_int32 count, le_int32 max, le_bool rightToLeft,
  51         LEUnicode *&outChars, LEGlyphStorage &glyphStorage, LEErrorCode &success)
  52 {
  53     if (LE_FAILURE(success)) {
  54         return 0;
  55     }
  56
  57     if (chars == NULL || offset < 0 || count < 0 || max < 0 || offset >= max || offset + count > max) {
  58         success = LE_ILLEGAL_ARGUMENT_ERROR;
  59         return 0;
  60     }
  61
  62     le_int32 worstCase = count * 3;  // worst case is 3 for Khmer  TODO check if 2 is enough
  63
  64     outChars = LE_NEW_ARRAY(LEUnicode, worstCase);
  65
  66     if (outChars == NULL) {
  67         success = LE_MEMORY_ALLOCATION_ERROR;
  68         return 0;
  69     }
  70
  71     glyphStorage.allocateGlyphArray(worstCase, rightToLeft, success);
  72     glyphStorage.allocateAuxData(success);
  73
  74     if (LE_FAILURE(success)) {
  75         LE_DELETE_ARRAY(outChars);
  76         return 0;
  77     }
  78
  79     // NOTE: assumes this allocates featureTags...
  80     // (probably better than doing the worst case stuff here...)
  81     le_int32 outCharCount = TibetanReordering::reorder(&chars[offset], count, fScriptCode, outChars, glyphStorage);
  82
  83     glyphStorage.adoptGlyphCount(outCharCount);
  84     return outCharCount;
  85 }
  86
  87 U_NAMESPACE_END