1 /* 2 * 3 * (C) Copyright IBM Corp. and others 1998-2013 - All Rights Reserved 4 * 5 */ 6 7 #ifndef __GXLAYOUTENGINE2_H 8 #define __GXLAYOUTENGINE2_H 9 10 #include "LETypes.h" 11 #include "LayoutEngine.h" 12 13 #include "MorphTables.h" 14 15 U_NAMESPACE_BEGIN 16 17 class LEFontInstance; 18 class LEGlyphStorage; 19 20 /** 21 * This class implements layout for QuickDraw GX or Apple Advanced Typograyph (AAT) 22 * fonts. A font is a GX or AAT font if it contains a 'mort' table. See Apple's 23 * TrueType Reference Manual (http://fonts.apple.com/TTRefMan/index.html) for details. 24 * Information about 'mort' tables is in the chapter titled "Font Files." 25 * 26 * @internal 27 */ 28 class GXLayoutEngine2 : public LayoutEngine 29 { 30 public: 31 /** 32 * This is the main constructor. It constructs an instance of GXLayoutEngine for 33 * a particular font, script and language. It takes the 'mort' table as a parameter since 34 * LayoutEngine::layoutEngineFactory has to read the 'mort' table to know that it has a 35 * GX font. 36 * 37 * Note: GX and AAT fonts don't contain any script and language specific tables, so 38 * the script and language are ignored. 39 * 40 * @param fontInstance - the font 41 * @param scriptCode - the script 42 * @param langaugeCode - the language 43 * @param morphTable - the 'mort' table 44 * @param success - set to an error code if the operation fails 45 * 46 * @see LayoutEngine::layoutEngineFactory 47 * @see ScriptAndLangaugeTags.h for script and language codes 48 * 49 * @internal 50 */ 51 GXLayoutEngine2(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode, const MorphTableHeader2 *morphTable, le_int32 typoFlags, LEErrorCode &success); 52 53 /** 54 * The destructor, virtual for correct polymorphic invocation. 55 * 56 * @internal 57 */ 58 virtual ~GXLayoutEngine2(); 59 60 /** 61 * ICU "poor man's RTTI", returns a UClassID for the actual class. 62 * 63 * @stable ICU 2.8 64 */ 65 virtual UClassID getDynamicClassID() const; 66 67 /** 68 * ICU "poor man's RTTI", returns a UClassID for this class. 69 * 70 * @stable ICU 2.8 71 */ 72 static UClassID getStaticClassID(); 73 74 protected: 75 76 /** 77 * The address of the 'mort' table 78 * 79 * @internal 80 */ 81 const MorphTableHeader2 *fMorphTable; 82 83 /** 84 * This method does GX layout using the font's 'mort' table. It converts the 85 * input character codes to glyph indices using mapCharsToGlyphs, and then 86 * applies the 'mort' table. 87 * 88 * Input parameters: 89 * @param chars - the input character context 90 * @param offset - the index of the first character to process 91 * @param count - the number of characters to process 92 * @param max - the number of characters in the input context 93 * @param rightToLeft - <code>TRUE</code> if the text is in a right to left directional run 94 * @param glyphStorage - the glyph storage object. The glyph and char index arrays will be set. 95 * 96 * Output parameters: 97 * @param success - set to an error code if the operation fails 98 * 99 * @return the number of glyphs in the glyph index array 100 * 101 * @internal 102 */ 103 virtual le_int32 computeGlyphs(const LEUnicode chars[], le_int32 offset, le_int32 count, le_int32 max, le_bool rightToLeft, 104 LEGlyphStorage &glyphStorage, LEErrorCode &success); 105 106 /** 107 * This method adjusts the glyph positions using the font's 108 * 'kern', 'trak', 'bsln', 'opbd' and 'just' tables. 109 * 110 * Input parameters: 111 * @param glyphStorage - the object holding the glyph storage. The positions will be updated as needed. 112 * 113 * Output parameters: 114 * @param success - set to an error code if the operation fails 115 * 116 * @internal 117 */ 118 virtual void adjustGlyphPositions(const LEUnicode chars[], le_int32 offset, le_int32 count, le_bool reverse, 119 LEGlyphStorage &glyphStorage, LEErrorCode &success); 120 121 }; 122 123 U_NAMESPACE_END 124 #endif 125 126
