1 2 /* 3 * 4 * (C) Copyright IBM Corp. 1998-2013 - All Rights Reserved 5 * 6 */ 7 8 #include "LETypes.h" 9 #include "LayoutEngine.h" 10 #include "ThaiLayoutEngine.h" 11 #include "ScriptAndLanguageTags.h" 12 #include "LEGlyphStorage.h" 13 14 #include "KernTable.h" 15 16 #include "ThaiShaping.h" 17 18 U_NAMESPACE_BEGIN 19 20 UOBJECT_DEFINE_RTTI_IMPLEMENTATION(ThaiLayoutEngine) 21 22 ThaiLayoutEngine::ThaiLayoutEngine(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode, le_int32 typoFlags, LEErrorCode &success) 23 : LayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, success) 24 { 25 fErrorChar = 0x25CC; 26 27 // Figure out which presentation forms the font uses 28 if (! fontInstance->canDisplay(0x0E01)) { 29 // No Thai in font; don't use presentation forms. 30 fGlyphSet = 3; 31 } else if (fontInstance->canDisplay(0x0E64)) { 32 // WorldType uses reserved space in Thai block 33 fGlyphSet = 0; 34 } else if (fontInstance->canDisplay(0xF701)) { 35 // Microsoft corporate zone 36 fGlyphSet = 1; 37 38 if (!fontInstance->canDisplay(fErrorChar)) { 39 fErrorChar = 0xF71B; 40 } 41 } else if (fontInstance->canDisplay(0xF885)) { 42 // Apple corporate zone 43 fGlyphSet = 2; 44 } else { 45 // no presentation forms in the font 46 fGlyphSet = 3; 47 } 48 } 49 50 ThaiLayoutEngine::~ThaiLayoutEngine() 51 { 52 // nothing to do 53 } 54 55 // Input: characters (0..max provided for context) 56 // Output: glyphs, char indices 57 // Returns: the glyph count 58 // NOTE: this assumes that ThaiShaping::compose will allocate the outChars array... 59 le_int32 ThaiLayoutEngine::computeGlyphs(const LEUnicode chars[], le_int32 offset, le_int32 count, le_int32 max, le_bool /*rightToLeft*/, LEGlyphStorage &glyphStorage, LEErrorCode &success) 60 { 61 if (LE_FAILURE(success)) { 62 return 0; 63 } 64 65 if (chars == NULL || offset < 0 || count < 0 || max < 0 || offset >= max || offset + count > max) { 66 success = LE_ILLEGAL_ARGUMENT_ERROR; 67 return 0; 68 } 69 70 LEUnicode *outChars; 71 le_int32 glyphCount; 72 73 // This is enough room for the worst-case expansion 74 // (it says here...) 75 outChars = LE_NEW_ARRAY(LEUnicode, count * 2); 76 77 if (outChars == NULL) { 78 success = LE_MEMORY_ALLOCATION_ERROR; 79 return 0; 80 } 81 82 glyphStorage.allocateGlyphArray(count * 2, FALSE, success); 83 84 if (LE_FAILURE(success)) { 85 LE_DELETE_ARRAY(outChars); 86 success = LE_MEMORY_ALLOCATION_ERROR; 87 return 0; 88 } 89 90 glyphCount = ThaiShaping::compose(chars, offset, count, fGlyphSet, fErrorChar, outChars, glyphStorage); 91 mapCharsToGlyphs(outChars, 0, glyphCount, FALSE, FALSE, glyphStorage, success); 92 93 LE_DELETE_ARRAY(outChars); 94 95 glyphStorage.adoptGlyphCount(glyphCount); 96 return glyphCount; 97 } 98 99 // This is the same as LayoutEngline::adjustGlyphPositions() except that it doesn't call adjustMarkGlyphs 100 void ThaiLayoutEngine::adjustGlyphPositions(const LEUnicode chars[], le_int32 offset, le_int32 count, le_bool /*reverse*/, 101 LEGlyphStorage &glyphStorage, LEErrorCode &success) 102 { 103 if (LE_FAILURE(success)) { 104 return; 105 } 106 107 if (chars == NULL || offset < 0 || count < 0) { 108 success = LE_ILLEGAL_ARGUMENT_ERROR; 109 return; 110 } 111 112 if (fTypoFlags & LE_Kerning_FEATURE_FLAG) { /* kerning enabled */ 113 LETableReference kernTable(fFontInstance, LE_KERN_TABLE_TAG, success); 114 KernTable kt(kernTable, success); 115 kt.process(glyphStorage, success); 116 } 117 118 // default is no adjustments 119 return; 120 } 121 122 U_NAMESPACE_END 123