diff -r 000000000000 -r bde4ae8d615e os/graphics/windowing/windowserver/inc/Graphics/openwfc/wselement.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/os/graphics/windowing/windowserver/inc/Graphics/openwfc/wselement.h	Fri Jun 15 03:10:57 2012 +0200
@@ -0,0 +1,498 @@
+// Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies).
+// All rights reserved.
+// This component and the accompanying materials are made available
+// under the terms of "Eclipse Public License v1.0"
+// which accompanies this distribution, and is available
+// at the URL "http://www.eclipse.org/legal/epl-v10.html".
+//
+// Initial Contributors:
+// Nokia Corporation - initial contribution.
+//
+// Contributors:
+//
+// Description:
+// Interface for Scene Elements
+// 
+//
+
+/**
+ @publishedPartner
+ @prototype
+*/
+
+#ifndef WSELEMENT_H
+#define WSELEMENT_H
+
+#include <w32std.h>
+#include <graphics/wsgraphicdrawerinterface.h>
+#include <graphics/surface.h>
+
+/**
+ * @brief Window Server Scene Element Interface Definition
+ *
+ * This interface allows Image Sources to be associated with meta-data
+ * to define how the Image Source must be presented within a Scene.
+ *
+ * For a conceptual overview of Scenes, refer to the @c MWsScene Interface.
+ *
+ * The following aspects of Image Source presentation may be controlled:
+ * @li Source rectangular region
+ * @li Destination rectangular region
+ * @li Rotation and flipping
+ * @li Opacity
+ * @li Relative z-order (ordinal position)
+ * @li Tags to descriminate the UI from other Elements
+ *
+ * All co-ordinates are pixels offsets from (0,0) representing the
+ * top level of the Image Source or Destination Target (the screen
+ * or an off-screen buffer representing the screen), moving rightwards
+ * and downwards in x and y co-ordinates respectively.
+ *
+ * Elements can be marked with flags.  There are two different consumers
+ * of flags: Target Renderers and Render Stage Plug-ins.
+ * 
+ * Target Renderers are sub-systems which actually do composition and
+ * rendering on a particular display device or off-screen buffer.
+ * The EElementTransparencySource flag tells the Target Renderer that 
+ * alpha blending must use the alpha channel in the Surface connected to
+ * the Element.
+ * 
+ * On the other hand, Render Stage Plug-ins need flags to implement
+ * specific policies such as "UI always on top".  To facilitate this,
+ * Elements have a EElementIsIndirectlyRenderedUserInterface or a
+ * EElementIsDirectlyRenderedUserInterface optionally set.  This
+ * flag allows Render Stage Plug-ins to keep the relative z-order
+ * of Elements aligned to this policy.
+ * 
+ * To allow compatible updates to be made to flags, all Render Stage
+ * Plug-ins must preserve the flags in Elements which they do not operate
+ * upon.  Target Renderers may ignore the flags in Elements which they
+ * do not operate on.
+ *
+ * <h2>Intial State</h2>
+ * 
+ * The initial state for an Element is:
+ * @li Fully opaque
+ * @li No rotation, nor flipped
+ * @li Not part of the Committed Scene
+ * @li No connected Surface
+ * @li All flags reset
+ * @li Local error value set as KErrNone
+ * @li Source Rectangle and Destination Rectangle is (0,0,0,0)
+ * @il Destination Clipping Rectangle is (0,0,0,0)
+ * 
+ * When an Image Source is connected, the initial state becomes:
+ * @li Source Rectangle is the extent of the Image Source
+ * @li Destination Rectangle is set at origin (0,0), whose sized equals the
+ *     Image Source size truncated the the target screen size.
+ * @li Destination Clipping Rectangle is (0,0,0,0) to represent the entire
+ *     area of the target screen.
+ * 
+ * <h2>Special Rectangle Values</h2>
+ * 
+ * Sometimes it is desirable to reset a Source, Destination, or Clipping
+ * Rectangle so that the actual value used matches the corresponding Source
+ * Image or Target Screen size.  In such cases rectangle (0,0,0,0) is used to
+ * represent this.
+ * 
+ * <h2>Extending this interface</h2>
+ * 
+ * This interface can be extended in two different ways
+ * @li Creating optional extension interfaces with 
+ *       MWsElement::MWsObjectProvider::ResolveObjectInterface()
+ * @li Defining new TElementFlags flag settings; Render Stage Plug-ins
+ *       preserve the value of these across the Render Stage Pipeline.
+ *
+ * <h2>Committed Elements versus Pending Elements</h2>
+ * 
+ * This interface allows Elements to be modified in terms of their
+ * own flag settings, and rotation, as well as their relative position
+ * with other Elements.  Queries return the pending values for such
+ * Elements.  Any modifications are marked Pending, and affect the Scene
+ * according to the rules described by "Rendering" in @c MWsScene.
+ * 
+ * <h2>Order in which transformations are applied</h2>
+ * 
+ * A number of different transformations may be specified for an Element.
+ * The order in which these are applied to arrive at the view seen in
+ * the target is:
+ * -# SetSourceRectangle              (Cropping)
+ * -# SetSourceFlipping               (Flipping)
+ * -# SetSourceRotation               (Rotation)
+ * -# SetDestinationRectangle         (Scaling and Positioning)
+ * -# SetDestinationClippingRectangle (Scaling and Positioning)
+ * -# SetGlobalAlpha                  (Blending)
+ */
+class MWsElement : public MWsObjectProvider
+    {
+public:
+    
+    /**
+     * @brief Flags used by Target Renderers.
+     */
+    enum TElementTargetRendererFlags
+        {
+        /**
+         * Target renderer must treat the Element as Opaque.
+         */
+        EElementTransparencyNone                 = 0,
+        /**
+         * Target renderer must use the Global Alpha Transparency value
+         * from the Element
+         */
+        EElementTransparencyGlobalAlpha          = (1 << 0),
+        /**
+         * Target renderer must use the Alpha Transparency Channel from
+         * the Element
+         */
+        EElementTransparencySource               = (1 << 1),
+        /**
+         * Reserved flag value; this must not be set.
+         */
+        EElementTargetRendererReserved           = (1 << 2)
+        };
+    
+    /**
+     * @brief Flags used by Render Stages.
+     */
+    enum TElementRenderStageFlags
+        {
+        /**
+         * No flag value set for Render Stage Plug-in
+         */
+        EElementRenderStageNone                   = 0,
+        /**
+         * Indirectly Rendered User Interface, i.e. rendering via 
+         * MWsGraphicsContext calls originating from client CWindowGc
+         * commands
+         */
+        EElementIsIndirectlyRenderedUserInterface = (1 << 0),
+        /**
+         * Directly Render User Interface, i.e. rendering where Window
+         * Server does not see the graphics commands, as is the case for
+         * Direct Screen Access clients.
+         */
+        EElementIsDirectlyRenderedUserInterface   = (1 << 1),
+        /**
+         * Reserved values for future Render Stage Plug-in usage
+         */
+        EElementRenderStageReserved               = (1 << 2)
+        };
+    
+    /**
+     * Amount of rotation of pixel data to apply to the Image Source
+     * to obtain the Target Image
+     */
+    enum TElementRotation
+        {
+        EElementAntiClockwise0   = 0, /** No rotation */
+        EElementAntiClockwise90  = 1, /** 90 Degrees Anti-clockwise in target */
+        EElementAntiClockwise180 = 2, /** 180 Degrees Anti-clockwise in target */
+        EElementAntiClockwise270 = 3  /** 270 Degrees Anti-clockwise in target */
+        };
+    
+public:
+    /**
+     * @brief Set which portion of the image source is used.
+     *
+     * Set which rectangular portion of the connected image source
+     * will be used when displaying this Element.
+     *
+     * @param aSrc  The source rectangle of pixels from the connected Image Source.
+     *              This rectangle must not include any pixels outside the Image
+     *              Source.  (0,0,0,0) means the entire size of the Image Source.
+     * @pre     An Image Source must have been connected; @see ConnectSurface()
+     * @return  One of the system-wide error codes.  
+     *          KErrGeneral, if there is no image source connected.
+     *          KErrArgument, if the source rectangle includes pixels not in the 
+     *          connected image source, or has negative width or height.  
+     *          KErrNone, if successful.
+     */
+    virtual TInt SetSourceRectangle(const TRect& aSrc) = 0;
+    
+    /**
+     * @brief Get the portion of the Image Source being used.
+     *
+     * Get the portion of the connected Image Source being used.  The default
+     * value is the entire extent of the connected Image Source.
+     *
+     * @param aSrc  The source rectangle is updated with the current rectangular
+     *              region being used within the Image Source.
+     * @pre     An Image Source must have been connected; @see ConnectSurface()
+     * @return  One of the system-wide error codes.  
+     *          KErrGeneral, if no Image Source has been connected.  
+     *          KErrNone, if successful.
+     */
+    virtual TInt GetSourceRectangle(TRect& aSrc) = 0;
+    
+    /**
+     * @brief Set the target area where the Image Source should appear.
+     * 
+     * Set the target area in the target screen (or off-screen buffer)
+     * where the Image Source should appear.  Scaling may result if
+     * the source and destination rectangles differ.  A platform specific
+     * algorithm will be used to interpolate the scaled image.
+     * 
+     * @param aDest  The destination rectangle in the target.
+     * @pre     An Image Source must have been connected; @see ConnectSurface()
+     * @return  One of the system-wide error codes.  
+     *          KErrGeneral, if there is no image source connected. 
+     *          KErrArgument, if the destination rectangle has negative width or 
+     *          height.  
+     *          KErrNone, if successful.
+     */
+    virtual TInt SetDestinationRectangle(const TRect& aDest) = 0;
+    
+    /**
+     * @brief Get the target area where the Image Source would appear.
+     * 
+     * Get the target area where the Image Source would appear.  The default
+     * value is at (0,0) sized to the Image Source clipped to the size
+     * of the target.
+     * 
+     * @param aDest  The destination rectangle is updated with the current
+     *               region used in the target screen. 
+     * @pre     An Image Source must have been connected; @see ConnectSurface()
+     * @return  One of the system-wide error codes.  
+     *          KErrGeneral, if no Image Source has been connected.  
+     *          KErrNone, if successful.
+     */
+    virtual TInt GetDestinationRectangle(TRect& aDest) const = 0;
+    
+    /**
+     * @brief Clip the target area where the Image Source would appear.
+     * 
+     * Set clipping area where the Image Source would appear.  The default
+     * value is the area of the target screen.
+     * 
+     * @param aDestClipRect  The clipping rectangle in the target.  (0,0,0,0)
+     *                       means the entire size of the Target Screen.
+     * @return  One of the system-wide error codes.  
+     *          KErrGeneral, if no Image Source has been connected. 
+     *          KErrArgument, if the rectangle has negative width or height  
+     *          KErrNone, if successful.
+     */
+    virtual TInt SetDestinationClippingRect(const TRect& aDestClipRect) = 0;
+    
+    /**
+     * @brief Get the clipping area in the target.
+     * 
+     * Get the clipping area which limits where in the target screen the
+     * element may appear.
+     * 
+     * @param aDestClipRect  The clipping rectangle is updated with the current
+     *                       clipping area used in the target screen.
+     * @return  One of the system-wide error codes.  KErrGeneral means no Image
+     *          Source has been connected.  KErrNone is returned upon success.      
+     */
+    virtual TInt GetDestinationClippingRect(TRect& aDestClipRect) const = 0;
+    
+    /**
+     * @brief Set the rotation that should appear in the target for the
+     * Image Source.
+     * 
+     * Set the rotation which describes how the connected Image Source
+     * should be rotated to appear in the target.
+     * 
+     * @param aElementRotation  The amount of rotation in the target.
+     * @pre     An Image Source must have been connected; @see ConnectSurface()
+     * @return  One of the system-wide error codes.  
+     *          KErrGeneral, if no Image Source has been connected.  
+     *          KErrArgument, if an out of bounds rotation value has been 
+     *          supplied.  
+     *          KErrNone, if successful.
+     */
+    virtual TInt SetSourceRotation(const TElementRotation aElementRotation) = 0;
+    
+    /**
+     * @brief Get the pending rotation setting as it would appear in the target.
+     * 
+     * Get the pending rotation setting for the connected Image Source.
+     * By default, the rotation is EElementAntiClockwise0 and this is returned
+     * if there is no connected Image Source.
+     * 
+     * @return  The pending rotation setting.
+     */
+    virtual TElementRotation SourceRotation() const = 0 ;
+    
+    /**
+     * @brief Set flipping about the image horizontal centerline.
+     * 
+     * Set the pending flipping setting for the connected Image Source.
+     * When flipped, the Image Source appears in the target as inverted
+     * about its horizontal centerline.  This effect can be combined
+     * with rotation effects.
+     * By default, the Image Source is not flipped.
+     * 
+     * @param aFlip  If ETrue, the connected Image is flipped, else
+     *               it is not flipped.
+     * @pre     An Image Source must have been connected; @see ConnectSurface()
+     * @return  One of the system-wide error codes.  
+     *          KErrGeneral, if no Image Source has been connceted.  
+     *          KErrNotSupported, if the platform does not support the feature.  
+     *          KErrNone, if successful.
+     */
+    virtual TInt SetSourceFlipping(const TBool aFlip) = 0;
+    
+    /**
+     * @brief Get the pending flipping setting.
+     * 
+     * Get the pending flipping setting for the connected Image Source.
+     * By default, the image is not flipped.
+     * 
+     * @return  The pending flipping setting.  If no Image is connected, return
+     *          EFalse.
+     */
+    virtual TBool SourceFlipping() const = 0 ;
+    
+    /**
+     * @brief Set Target Renderer Flags associated with this Element
+     * 
+     * Set the Target Renderer flags to be associated with this Element.
+     * 
+     * @note    Flags which are not recognised by an implementation must
+     *          be kept to allow the interface to be extended in a 
+     *          compatible manner.
+     * @param aTargetRendererFlags  Flags to set for Target Renderer;
+     *                              @see TElementTargetRendererFlags
+     * @return  One of the system-wide error codes.  
+     *          KErrNotSupported, if the platform does not support the given 
+     *          flags.  
+     *          KErrArgument, if incompatible flag settings have been made.  
+     *          KErrNone, if successful.
+     */
+    virtual TInt SetTargetRendererFlags(const TUint32& aTargetRendererFlags) = 0;
+    
+    /**
+     * @brief Set Render Stage Flags associated with this Element
+     * 
+     * Set the Render Stage flags to be associated with this Element.
+     * 
+     * @note    Flags which are not recognised by an implementation must
+     *          be kept to allow the interface to be extended in a 
+     *          compatible manner.
+     * @param aRenderStageFlags  Flags to set for Render Stage Plug-ins;
+     *                           @see TElementRenderStageFlags
+     * @return  One of the system-wide error codes.  
+     *          KErrNotSupported, if the platform does not support the given 
+     *          flags.  
+     *          KErrArgument, if incompatible flag settings have been requested.  
+     *          KErrNone, if successful.
+     */
+    virtual TInt SetRenderStageFlags(const TUint32& aRenderStageFlags) = 0;
+    
+    /**
+     * @brief Get Target Renderer Flags associated with this Element
+     * 
+     * Get the Target Renderer flags associated with this Element.
+     *   
+     * @note    Flags which are not recognised by an implementation must
+     *          be kept to allow the interface to be extended in a 
+     *          compatible manner.
+     * @param aTargetRendererFlags  Variable to receive TElementTargetRendererFlags
+     */
+    virtual void GetTargetRendererFlags(TUint32& aTargetRendererFlags) const = 0;
+
+    /**
+      * @brief Get Render Stage Flags associated with this Element
+      * 
+      * Get the Render Stage flags associated with this Element.
+      *   
+      * @note    Flags which are not recognised by an implementation must
+      *          be kept to allow the interface to be extended in a 
+      *          compatible manner.
+      * @param aRenderStageFlags  Variable to receive TElementRenderStageFlags
+      */
+     virtual void GetRenderStageFlags(TUint32& aRenderStageFlags) const = 0;   
+     
+    /**
+     * @brief Get the Element above this Element.
+     * 
+     * Get the Element which is above this Element in the Pending Scene.
+     * If the Element is the top-most element, NULL is returned.  If the
+     * Element is not in the Scene, NULL is returned.
+     * 
+     * @return Element above, or NULL.
+     */
+    virtual MWsElement *ElementAbove() = 0;
+    
+    /**
+     * @brief Get the Element below this Element.
+     * 
+     * Get the Element which is below this Element in the Pending Scene.
+     * If the Element is the bottom-most element, NULL is returned.  If the
+     * Element is not in the Scene, NULL is returned.
+     * 
+     * @return Element below, or NULL.
+     */
+    virtual MWsElement *ElementBelow() = 0;
+    
+    /**
+     * @brief Connect or re-Connect a Surface to this Element.
+     * 
+     * Connect the given Surface to this Element, or re-Connect a new
+     * Surface to this Element which already has a connected Surface.
+     * The Element does not need to be in the Scene when this call is made.
+     * 
+     * @note    The Source Rectangle of the Element is updated to correspond
+     *          to match the Source Rectangle of the Surface.  Thus any
+     *          prior Source Rectangle setting will be overwritten.
+     * 
+     * @param aSurface  Surface to connect to.  If this is the Null
+     *                  Surface, then the Source Rectangle of the
+     *                  Element is set to (0,0,0,0).
+     * @return  One of the system-wide error codes.  
+     *          KErrArgument, if supplied Surface cannot be connected.  For 
+     *          example the Element has a flag indicating it has an Alpha 
+     *          Channel but the Surface does not.  
+     *          KErrNone, if successful.
+     */
+    virtual TInt ConnectSurface(const TSurfaceId& aSurface) = 0;
+    
+    /**
+     * @brief Get the Surface connected to this Element
+     * 
+     * @return  The Surface Identifier of the Connected Surface.  This
+     *          identifier may represent the Null Surface Id if there
+     *          was no Surface connected in the Pending Scene for this
+     *          Element.
+     */
+    virtual const TSurfaceId& ConnectedSurface() const = 0;
+    
+    /**
+     * @brief Set the Global Alpha Transparency value
+     * 
+     * Sets the Global Alpha Transparency value for this Element.  Elements
+     * are by default fully opaque, represented by opacity 255.  On platforms
+     * that support it, the Alpha Transparency value can be reduced down
+     * to 0 representing fully transparent.  The purpose of this is to
+     * allow the fading in and fading out of Elements into the Scene.
+     * 
+     * @param aAlpha  The Alpha Transparency value desired.  Values
+     *                are clamped to be within the range [0, 255] where 0
+     *                represents fully transparent, and 255 represents
+     *                fully opaque.
+     * @note    This setting has no effect unless the flag
+     *          Target Renderer flag EElementTransparencyGlobalAlpha
+     *          is set; @see SetTargetRendererFlags()
+     * @note    Out of range values are clamped silently, and do not cause
+     *          error conditions.
+     * @return  One of the system-wide error codes.  
+     *          KErrNotSupported, if the supplied value, once clamped, is not 
+     *          supported on the platform.
+     *          KErrNone, if successful.
+     */
+    virtual TInt SetGlobalAlpha(const TInt aAlpha) = 0;
+    
+    /**
+     * @brief Get the Global Alpha Transparency value
+     * 
+     * Gets the Global Alpha Transparency value for this Element.  Elements
+     * are by default fully opaque, represented by opacity 255.
+     * 
+     * @param aAlpha  Variable which receives the Global Alpha Transparency
+     *                value.
+     */
+    virtual void GlobalAlpha(TInt& aAlpha) const = 0;
+    };
+#endif // WSELEMENT_H