text: /*
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
   * particular file as subject to the "Classpath" exception as provided
   * by Oracle in the LICENSE file that accompanied this code.
   *
   * This code is distributed in the hope that it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   * version 2 for more details (a copy is included in the LICENSE file that
   * accompanied this code).
   *
   * You should have received a copy of the GNU General Public License version
   * 2 along with this work; if not, write to the Free Software Foundation,
   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
   * or visit www.oracle.com if you need additional information or have any
   * questions.
   *
   */
  
  
  /*
   *
   * (C) Copyright IBM Corp. 1998-2004 - All Rights Reserved
   *
   */
  
  #ifndef __GXLAYOUTENGINE_H
  #define __GXLAYOUTENGINE_H
  
  #include "LETypes.h"
  #include "LayoutEngine.h"
  
  #include "MorphTables.h"
  
  U_NAMESPACE_BEGIN
  
  class LEFontInstance;
  class LEGlyphStorage;
  
  /**
   * This class implements layout for QuickDraw GX or Apple Advanced Typograyph (AAT)
   * fonts. A font is a GX or AAT font if it contains a 'mort' table. See Apple's
   * TrueType Reference Manual (http://fonts.apple.com/TTRefMan/index.html) for details.
   * Information about 'mort' tables is in the chapter titled "Font Files."
   *
   * @internal
   */
  class GXLayoutEngine : public LayoutEngine
  {
  public:
      /**
       * This is the main constructor. It constructs an instance of GXLayoutEngine for
       * a particular font, script and language. It takes the 'mort' table as a parameter since
       * LayoutEngine::layoutEngineFactory has to read the 'mort' table to know that it has a
       * GX font.
       *
       * Note: GX and AAT fonts don't contain any script and language specific tables, so
       * the script and language are ignored.
       *
       * @param fontInstance - the font
       * @param scriptCode - the script
       * @param langaugeCode - the language
       * @param morphTable - the 'mort' table
       * @param success - set to an error code if the operation fails
       *
       * @see LayoutEngine::layoutEngineFactory
       * @see ScriptAndLangaugeTags.h for script and language codes
       *
       * @internal
       */
      GXLayoutEngine(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode, const MorphTableHeader *morphTable, LEErrorCode &success);
  
      /**
       * The destructor, virtual for correct polymorphic invocation.
       *
       * @internal
       */
      virtual ~GXLayoutEngine();
  
      /**
       * ICU "poor man's RTTI", returns a UClassID for the actual class.
       *
       * @stable ICU 2.8
       */
      virtual UClassID getDynamicClassID() const;
  
      /**
       * ICU "poor man's RTTI", returns a UClassID for this class.
       *
       * @stable ICU 2.8
       */
      static UClassID getStaticClassID();
  
  protected:
  
      /**
       * The address of the 'mort' table
       *
       * @internal
       */
      const MorphTableHeader *fMorphTable;
  
      /**
       * This method does GX layout using the font's 'mort' table. It converts the
       * input character codes to glyph indices using mapCharsToGlyphs, and then
       * applies the 'mort' table.
       *
       * Input parameters:
       * @param chars - the input character context
       * @param offset - the index of the first character to process
       * @param count - the number of characters to process
       * @param max - the number of characters in the input context
       * @param rightToLeft - <code>TRUE</code> if the text is in a right to left directional run
       * @param glyphStorage - the glyph storage object. The glyph and char index arrays will be set.
       *
       * Output parameters:
       * @param success - set to an error code if the operation fails
       *
       * @return the number of glyphs in the glyph index array
       *
       * @internal
       */
      virtual le_int32 computeGlyphs(const LEUnicode chars[], le_int32 offset, le_int32 count, le_int32 max, le_bool rightToLeft,
          LEGlyphStorage &glyphStorage, LEErrorCode &success);
  
      /**
       * This method adjusts the glyph positions using the font's
       * 'kern', 'trak', 'bsln', 'opbd' and 'just' tables.
       *
       * Input parameters:
       * @param glyphStorage - the object holding the glyph storage. The positions will be updated as needed.
       *
       * Output parameters:
       * @param success - set to an error code if the operation fails
       *
       * @internal
       */
      virtual void adjustGlyphPositions(const LEUnicode chars[], le_int32 offset, le_int32 count, le_bool reverse,
                                        LEGlyphStorage &glyphStorage, LEErrorCode &success);
  
  };
  
  U_NAMESPACE_END
  #endif
  
  