Example #1
0
le_int32 LayoutEngine::characterProcessing(const LEUnicode chars[], le_int32 offset, le_int32 count, le_int32 max, le_bool rightToLeft,
                LEUnicode *&outChars, LEGlyphStorage &glyphStorage, LEErrorCode &success)
{
    if (LE_FAILURE(success)) {
        return 0;
    }

    if (offset < 0 || count < 0 || max < 0 || offset >= max || offset + count > max) {
        success = LE_ILLEGAL_ARGUMENT_ERROR;
        return 0;
    }

    if ((fTypoFlags & LE_NoCanon_FEATURE_FLAG) == 0) { // no canonical processing
      return count;
    }

    LEReferenceTo<GlyphSubstitutionTableHeader> canonGSUBTable(LETableReference::kStaticData,
                                                               (GlyphSubstitutionTableHeader *) CanonShaping::glyphSubstitutionTable,
                                                               CanonShaping::glyphSubstitutionTableLen);
    LETag scriptTag  = OpenTypeLayoutEngine::getScriptTag(fScriptCode);
    LETag langSysTag = OpenTypeLayoutEngine::getLangSysTag(fLanguageCode);
    le_int32 i, dir = 1, out = 0, outCharCount = count;

    if (canonGSUBTable->coversScript(canonGSUBTable,scriptTag, success) || LE_SUCCESS(success)) {
        CharSubstitutionFilter *substitutionFilter = new CharSubstitutionFilter(fFontInstance);
        if (substitutionFilter == NULL) {
            success = LE_MEMORY_ALLOCATION_ERROR;
            return 0;
        }

        const LEUnicode *inChars = &chars[offset];
        LEUnicode *reordered = NULL;
        LEGlyphStorage fakeGlyphStorage;

        fakeGlyphStorage.allocateGlyphArray(count, rightToLeft, success);

        if (LE_FAILURE(success)) {
            delete substitutionFilter;
            return 0;
        }

        // This is the cheapest way to get mark reordering only for Hebrew.
        // We could just do the mark reordering for all scripts, but most
        // of them probably don't need it...
        if (fScriptCode == hebrScriptCode) {
          reordered = LE_NEW_ARRAY(LEUnicode, count);

          if (reordered == NULL) {
            delete substitutionFilter;
            success = LE_MEMORY_ALLOCATION_ERROR;
            return 0;
          }

          CanonShaping::reorderMarks(&chars[offset], count, rightToLeft, reordered, fakeGlyphStorage);
          inChars = reordered;
                }

        fakeGlyphStorage.allocateAuxData(success);

        if (LE_FAILURE(success)) {
            delete substitutionFilter;
            return 0;
        }

        if (rightToLeft) {
            out = count - 1;
            dir = -1;
        }

        for (i = 0; i < count; i += 1, out += dir) {
            fakeGlyphStorage[out] = (LEGlyphID) inChars[i];
            fakeGlyphStorage.setAuxData(out, canonFeatures, success);
        }

        if (reordered != NULL) {
          LE_DELETE_ARRAY(reordered);
        }

        const LEReferenceTo<GlyphDefinitionTableHeader>  noGDEF; // empty gdef header
        outCharCount = canonGSUBTable->process(canonGSUBTable, fakeGlyphStorage, rightToLeft, scriptTag, langSysTag, noGDEF, substitutionFilter, canonFeatureMap, canonFeatureMapCount, FALSE, success);

        if (LE_FAILURE(success)) {
            delete substitutionFilter;
            return 0;
        }

        out = (rightToLeft? outCharCount - 1 : 0);

        /*
         * The char indices array in fakeGlyphStorage has the correct mapping
         * back to the original input characters. Save it in glyphStorage. The
         * subsequent call to glyphStoratge.allocateGlyphArray will keep this
         * array rather than allocating and initializing a new one.
         */
        glyphStorage.adoptCharIndicesArray(fakeGlyphStorage);

        outChars = LE_NEW_ARRAY(LEUnicode, outCharCount);

        if (outChars == NULL) {
            delete substitutionFilter;
            success = LE_MEMORY_ALLOCATION_ERROR;
            return 0;
        }

        for (i = 0; i < outCharCount; i += 1, out += dir) {
            outChars[out] = (LEUnicode) LE_GET_GLYPH(fakeGlyphStorage[i]);
        }

        delete substitutionFilter;
    }

    return outCharCount;
}