1 2 /* 3 * 4 * (C) Copyright IBM Corp. 1998-2008 - All Rights Reserved 5 * 6 */ 7 8 #ifndef __HANGULAYOUTENGINE_H 9 #define __HANGULAYOUTENGINE_H 10 11 #include "LETypes.h" 12 #include "LEFontInstance.h" 13 #include "LEGlyphFilter.h" 14 #include "LayoutEngine.h" 15 #include "OpenTypeLayoutEngine.h" 16 17 #include "GlyphSubstitutionTables.h" 18 #include "GlyphDefinitionTables.h" 19 #include "GlyphPositioningTables.h" 20 21 U_NAMESPACE_BEGIN 22 23 class MPreFixups; 24 class LEGlyphStorage; 25 26 /** 27 * This class implements OpenType layout for Old Hangul OpenType fonts, as 28 * specified by Microsoft in "Creating and Supporting OpenType Fonts for 29 * The Korean Hangul Script" (http://www.microsoft.com/typography/otfntdev/hangulot/default.htm) 30 * 31 * This class overrides the characterProcessing method to do Hangul character processing. 32 * (See the MS spec. for more details) 33 * 34 * @internal 35 */ 36 class HangulOpenTypeLayoutEngine : public OpenTypeLayoutEngine 37 { 38 public: 39 /** 40 * This is the main constructor. It constructs an instance of HangulOpenTypeLayoutEngine for 41 * a particular font, script and language. It takes the GSUB table as a parameter since 42 * LayoutEngine::layoutEngineFactory has to read the GSUB table to know that it has an 43 * Hangul OpenType font. 44 * 45 * @param fontInstance - the font 46 * @param scriptCode - the script 47 * @param langaugeCode - the language 48 * @param gsubTable - the GSUB table 49 * @param success - set to an error code if the operation fails 50 * 51 * @see LayoutEngine::layoutEngineFactory 52 * @see OpenTypeLayoutEngine 53 * @see ScriptAndLangaugeTags.h for script and language codes 54 * 55 * @internal 56 */ 57 HangulOpenTypeLayoutEngine(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode, 58 le_int32 typoFlags, const GlyphSubstitutionTableHeader *gsubTable, LEErrorCode &success); 59 60 /** 61 * This constructor is used when the font requires a "canned" GSUB table which can't be known 62 * until after this constructor has been invoked. 63 * 64 * @param fontInstance - the font 65 * @param scriptCode - the script 66 * @param langaugeCode - the language 67 * @param success - set to an error code if the operation fails 68 * 69 * @see OpenTypeLayoutEngine 70 * @see ScriptAndLangaugeTags.h for script and language codes 71 * 72 * @internal 73 */ 74 HangulOpenTypeLayoutEngine(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode, 75 le_int32 typoFlags, LEErrorCode &success); 76 77 /** 78 * The destructor, virtual for correct polymorphic invocation. 79 * 80 * @internal 81 */ 82 virtual ~HangulOpenTypeLayoutEngine(); 83 84 /** 85 * ICU "poor man's RTTI", returns a UClassID for the actual class. 86 * 87 * @stable ICU 2.8 88 */ 89 virtual UClassID getDynamicClassID() const; 90 91 /** 92 * ICU "poor man's RTTI", returns a UClassID for this class. 93 * 94 * @stable ICU 2.8 95 */ 96 static UClassID getStaticClassID(); 97 98 protected: 99 100 /** 101 * This method does Hangul OpenType character processing. It assigns the OpenType feature 102 * tags to the characters, and may compose a character sequence into a modern Hangul syllable, 103 * or decompose a modern Hangul syllable if it forms part of an old Hangul syllable. 104 * 105 * Input parameters: 106 * @param chars - the input character context 107 * @param offset - the index of the first character to process 108 * @param count - the number of characters to process 109 * @param max - the number of characters in the input context 110 * @param rightToLeft - <code>TRUE</code> if the characters are in a right to left directional run 111 * @param glyphStorage - the glyph storage object. The glyph and character index arrays will be set. 112 * the auxillary data array will be set to the feature tags. 113 * 114 * Output parameters: 115 * @param success - set to an error code if the operation fails 116 * 117 * @return the output character count 118 * 119 * @internal 120 */ 121 virtual le_int32 characterProcessing(const LEUnicode chars[], le_int32 offset, le_int32 count, le_int32 max, le_bool rightToLeft, 122 LEUnicode *&outChars, LEGlyphStorage &glyphStorage, LEErrorCode &success); 123 }; 124 125 U_NAMESPACE_END 126 #endif 127 128