S60 3rd Edition SDK for Symbian OS Example Applications Guide

HierarchyContainer.h

/*
* ==============================================================================
*  Name        : HierarchyContainer.h
*  Part of     : OpenGLEx / Hierarchy
*  Interface   : 
*  Description : 
*  Version     : 
*
*  Copyright (c) 2004-2006 Nokia Corporation.
*  This material, including documentation and any related 
*  computer programs, is protected by copyright controlled by 
*  Nokia Corporation.
* ==============================================================================
*/

#ifndef HIERARCHYCONTAINER_H
#define HIERARCHYCONTAINER_H

// INCLUDES
#include <coecntrl.h>
#include <GLES/egl.h>   
#include "Hierarchy.h"
#include <akndef.h>

// CLASS DECLARATION

/**
 * Container control class that handles the OpenGL ES initialization and deinitializations.
 * Also uses the CHierarchy class to do the actual OpenGL ES rendering.
 */
class CHierarchyContainer : public CCoeControl, MCoeControlObserver
    {
    public: // Constructors and destructor
        
        /**
         * EPOC default constructor. Initializes the OpenGL ES for rendering to the window surface.
         * @param aRect Screen rectangle for container.
         */
        void ConstructL(const TRect& aRect);

        /**
         * Destructor. Destroys the CPeriodic, CHierarchy and uninitializes OpenGL ES.
         */
        virtual ~CHierarchyContainer();

    public: // New functions
    
        /**
         * Callback function for the CPeriodic. Calculates the current frame, keeps the background
         * light from turning off and orders the CHierarchy to do the rendering for each frame.
         *@param aInstance Pointer to this instance of CHierarchyContainer.
         */
        static int DrawCallBack( TAny* aInstance );

    private: // Functions from base classes

        /**
         * Method from CoeControl that gets called when the display size changes.
         * If OpenGL has been initialized, notifies the renderer class that the screen
         * size has changed.
         */
        void SizeChanged();

        /**
         * Handles a change to the control's resources. This method
         * reacts to the KEikDynamicLayoutVariantSwitch event (that notifies of
         * screen size change) by calling the SetExtentToWholeScreen() again so that
         * this control fills the new screen size. This will then trigger a call to the
         * SizeChanged() method.
         * @param aType Message UID value, only KEikDynamicLayoutVariantSwitch is handled by this method.
         */
        void HandleResourceChange(TInt aType); 

        /**
         * Method from CoeControl. Does nothing in this implementation.
         */
        TInt CountComponentControls() const;

        /**
         * Method from CCoeControl. Does nothing in this implementation.
         */
        CCoeControl* ComponentControl(TInt aIndex) const;

        /**
         * Method from CCoeControl. Does nothing in this implementation.
         * All rendering is done in the DrawCallBack() method.
         */
        void Draw(const TRect& aRect) const;

        /**
         * Method from MCoeControlObserver that handles an event from the observed control.
         * Does nothing in this implementation.
                 * @param aControl   Control changing its state.
                 * @param aEventType Type of the control event.
         */
        void HandleControlEventL(CCoeControl* aControl,TCoeEvent aEventType);
        
    private: //data

        /** Display where the OpenGL ES window surface resides. */
        EGLDisplay  iEglDisplay;
        
        /** Window surface where the OpenGL ES rendering is blitted to. */
        EGLSurface  iEglSurface; 

        /** OpenGL ES rendering context. */
        EGLContext  iEglContext;
        
        /** Active object that is the timing source for the animation. */
        CPeriodic*  iPeriodic;   

        /**
         * Flag that indicates if OpenGL ES has been initialized or not.
         * Used to check if SizeChanged() can react to incoming notifications.
         */
        TBool iOpenGlInitialized;

        /** Frame counter variable, used in the animation. */
        TInt iFrame;

    public:  //data
        
        /** Used in DrawCallBack() method to do the actual OpenGL ES rendering.  */
        CHierarchy* iHierarchy;  
    };

#endif

// End of File

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© Nokia 2006