diff -r 000000000000 -r bde4ae8d615e os/textandloc/fontservices/textshaperplugin/IcuSource/layout/LayoutEngine.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/os/textandloc/fontservices/textshaperplugin/IcuSource/layout/LayoutEngine.h	Fri Jun 15 03:10:57 2012 +0200
@@ -0,0 +1,494 @@
+
+/*
+ *
+ * (C) Copyright IBM Corp. 1998-2005 - All Rights Reserved
+ *
+ */
+
+#ifndef __LAYOUTENGINE_H
+#define __LAYOUTENGINE_H
+
+#include "LETypes.h"
+
+/**
+ * \file 
+ * \brief C++ API: Virtual base class for complex text layout.
+ */
+
+U_NAMESPACE_BEGIN
+
+class LEFontInstance;
+class LEGlyphFilter;
+class LEGlyphStorage;
+
+/**
+ * This is a virtual base class used to do complex text layout. The text must all
+ * be in a single font, script, and language. An instance of a LayoutEngine can be
+ * created by calling the layoutEngineFactory method. Fonts are identified by
+ * instances of the LEFontInstance class. Script and language codes are identified
+ * by integer codes, which are defined in ScriptAndLanuageTags.h.
+ *
+ * Note that this class is not public API. It is declared public so that it can be
+ * exported from the library that it is a part of.
+ *
+ * The input to the layout process is an array of characters in logical order,
+ * and a starting X, Y position for the text. The output is an array of glyph indices,
+ * an array of character indices for the glyphs, and an array of glyph positions.
+ * These arrays are protected members of LayoutEngine which can be retreived by a
+ * public method. The reset method can be called to free these arrays so that the
+ * LayoutEngine can be reused.
+ *
+ * The layout process is done in three steps. There is a protected virtual method
+ * for each step. These methods have a default implementation which only does
+ * character to glyph mapping and default positioning using the glyph's advance
+ * widths. Subclasses can override these methods for more advanced layout.
+ * There is a public method which invokes the steps in the correct order.
+ * 
+ * The steps are:
+ *
+ * 1) Glyph processing - character to glyph mapping and any other glyph processing
+ *    such as ligature substitution and contextual forms.
+ *
+ * 2) Glyph positioning - position the glyphs based on their advance widths.
+ *
+ * 3) Glyph position adjustments - adjustment of glyph positions for kerning,
+ *    accent placement, etc.
+ *
+ * NOTE: in all methods below, output parameters are references to pointers so
+ * the method can allocate and free the storage as needed. All storage allocated
+ * in this way is owned by the object which created it, and will be freed when it
+ * is no longer needed, or when the object's destructor is invoked.
+ *
+ * @see LEFontInstance
+ * @see ScriptAndLanguageTags.h
+ *
+ * @stable ICU 2.8
+ */
+class U_LAYOUT_API LayoutEngine : public UObject {
+protected:
+    /**
+     * The object which holds the glyph storage
+     *
+     * @internal
+     */
+    LEGlyphStorage *fGlyphStorage;
+
+    /**
+     * The font instance for the text font.
+     *
+     * @see LEFontInstance
+     *
+     * @internal
+     */
+    const LEFontInstance *fFontInstance;
+
+    /**
+     * The script code for the text
+     *
+     * @see ScriptAndLanguageTags.h for script codes.
+     *
+     * @internal
+     */
+    le_int32 fScriptCode;
+
+    /**
+     * The langauge code for the text
+     *
+     * @see ScriptAndLanguageTags.h for language codes.
+     *
+     * @internal
+     */
+    le_int32 fLanguageCode;
+
+    /**
+     * The typographic control flags
+     *
+     * @internal
+     */
+    le_int32 fTypoFlags;
+
+    /**
+     * The glyph ID of Malayalam RA for RAKAR
+     *
+     * @internal
+     */
+    LEGlyphID fGidOfRA;
+    
+    /**
+     * This constructs an instance for a given font, script and language. Subclass constructors
+     * must call this constructor.
+     *
+     * @param fontInstance - the font for the text
+     * @param scriptCode - the script for the text
+     * @param languageCode - the language for the text
+     * @param typoFlags - the typographic control flags for the text.  Set bit 1 if kerning
+     * is desired, set bit 2 if ligature formation is desired.  Others are reserved.
+     *
+     * @see LEFontInstance
+     * @see ScriptAndLanguageTags.h
+     *
+     * @internal
+     */
+    LayoutEngine(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode, le_int32 typoFlags);
+
+    /**
+     * Returns true if the constructor failed, leaving the object in an
+     * inconsistent state.
+     *
+     * @internal
+     */
+    le_bool isBogus();
+
+    /**
+     * This overrides the default no argument constructor to make it
+     * difficult for clients to call it. Clients are expected to call
+     * layoutEngineFactory.
+     *
+     * @internal
+     */
+    LayoutEngine();
+
+    /**
+     * This method does any required pre-processing to the input characters. It
+     * may generate output characters that differ from the input charcters due to
+     * insertions, deletions, or reorderings. In such cases, it will also generate an
+     * output character index array reflecting these changes.
+     *
+     * Subclasses must override this method.
+     *
+     * 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 - TRUE if the characters are in a right to left directional run
+     * @param outChars - the output character array, if different from the input
+     * @param glyphStorage - the object that holds the per-glyph storage. The character index array may be set.
+     * @param success - set to an error code if the operation fails
+     *
+     * @return the output character count (input character count if no change)
+     *
+     * @internal
+     */
+    virtual le_int32 characterProcessing(const LEUnicode chars[], le_int32 offset, le_int32 count, le_int32 max, le_bool rightToLeft,
+            LEUnicode *&outChars, LEGlyphStorage &glyphStorage, LEErrorCode &success);
+
+    /**
+     * This method does the glyph processing. It converts an array of characters
+     * into an array of glyph indices and character indices. The characters to be
+     * processed are passed in a surrounding context. The context is specified as
+     * a starting address and a maximum character count. An offset and a count are
+     * used to specify the characters to be processed.
+     *
+     * The default implementation of this method only does character to glyph mapping.
+     * Subclasses needing more elaborate glyph processing must override this method.
+     *
+     * Input parameters:
+     * @param chars - the character context
+     * @param offset - the offset of the first character to process
+     * @param count - the number of characters to process
+     * @param max - the number of characters in the context.
+     * @param rightToLeft - TRUE if the text is in a right to left directional run
+     * @param glyphStorage - the object which holds the per-glyph storage. The glyph and char indices 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 does basic glyph positioning. The default implementation positions
+     * the glyphs based on their advance widths. This is sufficient for most uses. It
+     * is not expected that many subclasses will override this method.
+     *
+     * Input parameters:
+     * @param glyphStorage - the object which holds the per-glyph storage. The glyph position array will be set.
+     * @param x - the starting X position
+     * @param y - the starting Y position
+     * @param success - set to an error code if the operation fails
+     *
+     * @internal
+     */
+    virtual void positionGlyphs(LEGlyphStorage &glyphStorage, float x, float y, LEErrorCode &success);
+
+    /**
+     * This method does positioning adjustments like accent positioning and
+     * kerning. The default implementation does nothing. Subclasses needing
+     * position adjustments must override this method.
+     *
+     * Note that this method has both characters and glyphs as input so that
+     * it can use the character codes to determine glyph types if that information
+     * isn't directly available. (e.g. Some Arabic OpenType fonts don't have a GDEF
+     * table)
+     *
+     * @param chars - the input character context
+     * @param offset - the offset of the first character to process
+     * @param count - the number of characters to process
+     * @param reverse - <code>TRUE</code> if the glyphs in the glyph array have been reordered
+     * @param glyphStorage - the object which holds the per-glyph storage. The glyph positions will be
+     *                       adjusted as needed.
+     * @param success - output parameter 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);
+
+    /**
+     * This method gets a table from the font associated with
+     * the text. The default implementation gets the table from
+     * the font instance. Subclasses which need to get the tables
+     * some other way must override this method.
+     * 
+     * @param tableTag - the four byte table tag.
+     *
+     * @return the address of the table.
+     *
+     * @internal
+     */
+    virtual const void *getFontTable(LETag tableTag) const;
+
+    /**
+     * This method does character to glyph mapping. The default implementation
+     * uses the font instance to do the mapping. It will allocate the glyph and
+     * character index arrays if they're not already allocated. If it allocates the
+     * character index array, it will fill it it.
+     *
+     * This method supports right to left
+     * text with the ability to store the glyphs in reverse order, and by supporting
+     * character mirroring, which will replace a character which has a left and right
+     * form, such as parens, with the opposite form before mapping it to a glyph index.
+     *
+     * Input parameters:
+     * @param chars - the input character context
+     * @param offset - the offset of the first character to be mapped
+     * @param count - the number of characters to be mapped
+     * @param reverse - if <code>TRUE</code>, the output will be in reverse order
+     * @param mirror - if <code>TRUE</code>, do character mirroring
+     * @param glyphStorage - the object which holds the per-glyph storage. The glyph and char
+     *                       indices arrays will be filled in.
+     * @param success - set to an error code if the operation fails
+     *
+     * @see LEFontInstance
+     *
+     * @internal
+     */
+    virtual void mapCharsToGlyphs(const LEUnicode chars[], le_int32 offset, le_int32 count, le_bool reverse, le_bool mirror, LEGlyphStorage &glyphStorage, LEErrorCode &success);
+
+    /**
+     * This is a convenience method that forces the advance width of mark
+     * glyphs to be zero, which is required for proper selection and highlighting.
+     * 
+     * @param glyphStorage - the object containing the per-glyph storage. The positions array will be modified.
+     * @param markFilter - used to identify mark glyphs
+     * @param success - output parameter set to an error code if the operation fails
+     *
+     * @see LEGlyphFilter
+     *
+     * @internal
+     */
+    static void adjustMarkGlyphs(LEGlyphStorage &glyphStorage, LEGlyphFilter *markFilter, LEErrorCode &success);
+
+
+    /**
+     * This is a convenience method that forces the advance width of mark
+     * glyphs to be zero, which is required for proper selection and highlighting.
+     * This method uses the input characters to identify marks. This is required in
+     * cases where the font does not contain enough information to identify them based
+     * on the glyph IDs.
+     * 
+     * @param chars - the array of input characters
+     * @param charCount - the number of input characers
+     * @param glyphStorage - the object containing the per-glyph storage. The positions array will be modified.
+     * @param reverse - <code>TRUE</code> if the glyph array has been reordered
+     * @param markFilter - used to identify mark glyphs
+     * @param success - output parameter set to an error code if the operation fails
+     *
+     * @see LEGlyphFilter
+     *
+     * @internal
+     */
+    static void adjustMarkGlyphs(const LEUnicode chars[], le_int32 charCount, le_bool reverse, LEGlyphStorage &glyphStorage, LEGlyphFilter *markFilter, LEErrorCode &success);
+
+
+public:
+    /**
+     * The destructor. It will free any storage allocated for the
+     * glyph, character index and position arrays by calling the reset
+     * method. It is declared virtual so that it will be invoked by the
+     * subclass destructors.
+     *
+     * @stable ICU 2.8
+     */
+    virtual ~LayoutEngine();
+
+    /**
+     * This method will invoke the layout steps in their correct order by calling
+     * the computeGlyphs, positionGlyphs and adjustGlyphPosition methods.. It will
+     * compute the glyph, character index and position arrays.
+     *
+     * @param chars - the input character context
+     * @param offset - the offset 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 - TRUE if the characers are in a right to left directional run
+     * @param x - the initial X position
+     * @param y - the initial Y position
+     * @param success - output parameter set to an error code if the operation fails
+     *
+     * @return the number of glyphs in the glyph array
+     *
+     * Note; the glyph, character index and position array can be accessed
+     * using the getter method below.
+     *
+     * @stable ICU 2.8
+     */
+    virtual le_int32 layoutChars(const LEUnicode chars[], le_int32 offset, le_int32 count, le_int32 max, le_bool rightToLeft, float x, float y, LEErrorCode &success);
+
+    /**
+     * This method returns the number of glyphs in the glyph array. Note
+     * that the number of glyphs will be greater than or equal to the number
+     * of characters used to create the LayoutEngine.
+     *
+     * @return the number of glyphs in the glyph array
+     *
+     * @stable ICU 2.8
+     */
+    le_int32 getGlyphCount() const;
+
+    /**
+     * This method copies the glyph array into a caller supplied array.
+     * The caller must ensure that the array is large enough to hold all
+     * the glyphs.
+     *
+     * @param glyphs - the destiniation glyph array
+     * @param success - set to an error code if the operation fails
+     *
+     * @stable ICU 2.8
+     */
+    void getGlyphs(LEGlyphID glyphs[], LEErrorCode &success) const;
+
+    /**
+     * This method copies the glyph array into a caller supplied array,
+     * ORing in extra bits. (This functionality is needed by the JDK,
+     * which uses 32 bits pre glyph idex, with the high 16 bits encoding
+     * the composite font slot number)
+     *
+     * @param glyphs - the destination (32 bit) glyph array
+     * @param extraBits - this value will be ORed with each glyph index
+     * @param success - set to an error code if the operation fails
+     *
+     * @stable ICU 2.8
+     */
+    virtual void getGlyphs(le_uint32 glyphs[], le_uint32 extraBits, LEErrorCode &success) const;
+
+    /**
+     * This method copies the character index array into a caller supplied array.
+     * The caller must ensure that the array is large enough to hold a
+     * character index for each glyph.
+     *
+     * @param charIndices - the destiniation character index array
+     * @param success - set to an error code if the operation fails
+     *
+     * @stable ICU 2.8
+     */
+    void getCharIndices(le_int32 charIndices[], LEErrorCode &success) const;
+
+    /**
+     * This method copies the character index array into a caller supplied array.
+     * The caller must ensure that the array is large enough to hold a
+     * character index for each glyph.
+     *
+     * @param charIndices - the destiniation character index array
+     * @param indexBase - an offset which will be added to each index
+     * @param success - set to an error code if the operation fails
+     *
+     * @stable ICU 2.8
+     */
+    void getCharIndices(le_int32 charIndices[], le_int32 indexBase, LEErrorCode &success) const;
+
+    /**
+     * This method copies the position array into a caller supplied array.
+     * The caller must ensure that the array is large enough to hold an
+     * X and Y position for each glyph, plus an extra X and Y for the
+     * advance of the last glyph.
+     *
+     * @param positions - the destiniation position array
+     * @param success - set to an error code if the operation fails
+     *
+     * @stable ICU 2.8
+     */
+    void getGlyphPositions(float positions[], LEErrorCode &success) const;
+
+    /**
+     * This method returns the X and Y position of the glyph at
+     * the given index.
+     *
+     * Input parameters:
+     * @param glyphIndex - the index of the glyph
+     *
+     * Output parameters:
+     * @param x - the glyph's X position
+     * @param y - the glyph's Y position
+     * @param success - set to an error code if the operation fails
+     *
+     * @stable ICU 2.8
+     */
+    void getGlyphPosition(le_int32 glyphIndex, float &x, float &y, LEErrorCode &success) const;
+
+    /**
+     * This method frees the glyph, character index and position arrays
+     * so that the LayoutEngine can be reused to layout a different
+     * characer array. (This method is also called by the destructor)
+     *
+     * @stable ICU 2.8
+     */
+    virtual void reset();
+
+    /**
+     * This method returns a LayoutEngine capable of laying out text
+     * in the given font, script and langauge. Note that the LayoutEngine
+     * returned may be a subclass of LayoutEngine.
+     *
+     * @param fontInstance - the font of the text
+     * @param scriptCode - the script of the text
+     * @param languageCode - the language of the text
+     * @param success - output parameter set to an error code if the operation fails
+     *
+     * @return a LayoutEngine which can layout text in the given font.
+     *
+     * @see LEFontInstance
+     *
+     * @stable ICU 2.8
+     */
+    static LayoutEngine *layoutEngineFactory(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode, LEErrorCode &success);
+
+    /**
+     * Override of existing call that provides flags to control typography.
+     * @draft ICU 3.4
+     */
+    static LayoutEngine *layoutEngineFactory(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode, le_int32 typo_flags, LEErrorCode &success);
+
+    /**
+     * 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();
+
+};
+
+U_NAMESPACE_END
+#endif
+