sl@0: 
sl@0: /*
sl@0:  *
sl@0:  * (C) Copyright IBM Corp. 1998-2004 - All Rights Reserved
sl@0:  *
sl@0:  */
sl@0: 
sl@0: #ifndef __GXLAYOUTENGINE_H
sl@0: #define __GXLAYOUTENGINE_H
sl@0: 
sl@0: #include "LETypes.h"
sl@0: #include "LayoutEngine.h"
sl@0: 
sl@0: #include "MorphTables.h"
sl@0: 
sl@0: U_NAMESPACE_BEGIN
sl@0: 
sl@0: class LEFontInstance;
sl@0: class LEGlyphStorage;
sl@0: 
sl@0: /**
sl@0:  * This class implements layout for QuickDraw GX or Apple Advanced Typograyph (AAT)
sl@0:  * fonts. A font is a GX or AAT font if it contains a 'mort' table. See Apple's
sl@0:  * TrueType Reference Manual (http://fonts.apple.com/TTRefMan/index.html) for details.
sl@0:  * Information about 'mort' tables is in the chapter titled "Font Files."
sl@0:  *
sl@0:  * @internal
sl@0:  */
sl@0: class GXLayoutEngine : public LayoutEngine
sl@0: {
sl@0: public:
sl@0:     /**
sl@0:      * This is the main constructor. It constructs an instance of GXLayoutEngine for
sl@0:      * a particular font, script and language. It takes the 'mort' table as a parameter since
sl@0:      * LayoutEngine::layoutEngineFactory has to read the 'mort' table to know that it has a
sl@0:      * GX font.
sl@0:      *
sl@0:      * Note: GX and AAT fonts don't contain any script and language specific tables, so
sl@0:      * the script and language are ignored.
sl@0:      *
sl@0:      * @param fontInstance - the font
sl@0:      * @param scriptCode - the script
sl@0:      * @param langaugeCode - the language
sl@0:      * @param morphTable - the 'mort' table
sl@0:      *
sl@0:      * @see LayoutEngine::layoutEngineFactory
sl@0:      * @see ScriptAndLangaugeTags.h for script and language codes
sl@0:      *
sl@0:      * @internal
sl@0:      */
sl@0:     GXLayoutEngine(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode, const MorphTableHeader *morphTable);
sl@0: 
sl@0:     /**
sl@0:      * The destructor, virtual for correct polymorphic invocation.
sl@0:      *
sl@0:      * @internal
sl@0:      */
sl@0:     virtual ~GXLayoutEngine();
sl@0: 
sl@0:     /**
sl@0:      * ICU "poor man's RTTI", returns a UClassID for the actual class.
sl@0:      *
sl@0:      * @stable ICU 2.8
sl@0:      */
sl@0:     virtual UClassID getDynamicClassID() const;
sl@0: 
sl@0:     /**
sl@0:      * ICU "poor man's RTTI", returns a UClassID for this class.
sl@0:      *
sl@0:      * @stable ICU 2.8
sl@0:      */
sl@0:     static UClassID getStaticClassID();
sl@0: 
sl@0: protected:
sl@0: 
sl@0:     /**
sl@0:      * The address of the 'mort' table
sl@0:      *
sl@0:      * @internal
sl@0:      */
sl@0:     const MorphTableHeader *fMorphTable;
sl@0: 
sl@0:     /**
sl@0:      * This method does GX layout using the font's 'mort' table. It converts the
sl@0:      * input character codes to glyph indices using mapCharsToGlyphs, and then
sl@0:      * applies the 'mort' table.
sl@0:      *
sl@0:      * Input parameters:
sl@0:      * @param chars - the input character context
sl@0:      * @param offset - the index of the first character to process
sl@0:      * @param count - the number of characters to process
sl@0:      * @param max - the number of characters in the input context
sl@0:      * @param rightToLeft - <code>TRUE</code> if the text is in a right to left directional run
sl@0:      * @param glyphStorage - the glyph storage object. The glyph and char index arrays will be set.
sl@0:      *
sl@0:      * Output parameters:
sl@0:      * @param success - set to an error code if the operation fails
sl@0:      *
sl@0:      * @return the number of glyphs in the glyph index array
sl@0:      *
sl@0:      * @internal
sl@0:      */
sl@0:     virtual le_int32 computeGlyphs(const LEUnicode chars[], le_int32 offset, le_int32 count, le_int32 max, le_bool rightToLeft,
sl@0:         LEGlyphStorage &glyphStorage, LEErrorCode &success);
sl@0: 
sl@0:     /**
sl@0:      * This method adjusts the glyph positions using the font's
sl@0:      * 'kern', 'trak', 'bsln', 'opbd' and 'just' tables.
sl@0:      *
sl@0:      * Input parameters:
sl@0:      * @param glyphStorage - the object holding the glyph storage. The positions will be updated as needed.
sl@0:      *
sl@0:      * Output parameters:
sl@0:      * @param success - set to an error code if the operation fails
sl@0:      *
sl@0:      * @internal
sl@0:      */
sl@0:     virtual void adjustGlyphPositions(const LEUnicode chars[], le_int32 offset, le_int32 count, le_bool reverse,
sl@0:                                       LEGlyphStorage &glyphStorage, LEErrorCode &success);
sl@0: 
sl@0: };
sl@0: 
sl@0: U_NAMESPACE_END
sl@0: #endif
sl@0: