// Copyright (c) 2007-2009 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:

//

#ifndef GLYPHIMAGECACHE_H_

#define GLYPHIMAGECACHE_H_

/**

@file

@internalComponent

*/

#include <e32base.h>

#include <gdi.h>

#include <s32btree.h>

#include <VG/openvg.h>

#include <graphics/directgdiextensioninterfaces.h>

/**

Data structure which holds OpenVG images for monochrome and anti-aliased fonts

*/

class TGlyphEntry

	{

public:

	TChar iGlyphCode; 		//unique code, used as an index in a tree

	VGImage	iForeground; 	//blend using a brush colour

	};

/**

Data structure which holds OpenVG images for compound fonts.

These fonts are specified by four components:

	-foreground

	-background  

	-shadow

	-outline

*/

class TGlyphEntryCompound : public TGlyphEntry

	{

public:

	VGImage iOutline; //blend using a pen colour

	VGImage iShadow; //blend using a shadow colour

	};

/**

This class represents the concrete implementation of the CFontGlyphImageStorage.

It holds all entries in the form of a binary tree and provides functionality for image creation and searching.

*/

NONSHARABLE_CLASS(CFontGlyphTree) : public CBase

	{

public:

	static CFontGlyphTree* NewL(TUint32 aFontId, TGlyphBitmapType aGlyphType);

	~CFontGlyphTree();

template <class K>

	void GlyphImageEntryL(TChar aGlyphCode, const TUint8* aGlyphImage, const TSize& aGlyphImageSize, K& aEntry, TUint8* aDataForeground);

	inline TUint32 FontId() const;

	inline TUint CacheSize() const;

	void DestroyAllVGImagesL();

	//do not add to the tree. For OOM conditions

template <class K>

	static void GlyphImageEntryOOML(TGlyphBitmapType aGlyphType, const TUint8* aGlyphImage, const TSize& aGlyphImageSize, K& aEntry, TUint8* aData, TUint8* aDataOutline, TUint8* aDataShadow);

private:

	CFontGlyphTree(TUint32 aFontId, TGlyphBitmapType aGlyphType);

	void ConstructL();

	static void DestroyVGImage(VGImage* aForeground, VGImage* aOutline = NULL, VGImage* aShadow = NULL);

	//for monochrome and antialiased fonts

	static void CreateVGImageL(const TUint8* aGlyphImage, const TSize& aGlyphImageSize, TDisplayMode aDisplayMode, VGImage& aForeground, TUint8* aPreAllocForeground);

	//for four colours fonts

	static void CreateVGImageL(const TUint8* aGlyphImage, const TSize& aGlyphImageSize, VGImage& aForeground, VGImage& aOutline, VGImage& aShadow, TUint8* aPreAllocForeground, TUint8* aPreAllocOutline, TUint8* aPreAllocShadow);

	static void DecodeBinaryData(const TSize& aDataSize, const TUint8* aData, TUint32* aBinaryData);

	static void DecodeBinaryDataExLarge(const TSize& aDataSize, const TUint8* aData, TInt aStride, TUint32* aBinaryData);

	inline static TInt16 Load16(const TUint8* aPtr);

	static void CopyCharLine(TUint32*& aBinaryDataPtr,TInt aBufferWords,const TUint8* aData,TInt aBitShift,TInt aCharWidth, TInt16 aRepeatCount);

private:

	/**

	Binary tree with fixed size. One of following will be used:

	TBtreeFix<TGlyphEntry, TChar> or TBtreeFix<TGlyphEntryCompound, TChar>

	*/

	TBtree* iGlyphTree;

	CMemPagePool* iPagePool; /**< Non persistent pool for pages.*/

	TBtreeKey iKey; /**< Tree key.*/

	TUint32 iFontId; /**< Unique font id.*/

	TGlyphBitmapType iGlyphType; /**< Glyph bitmap type.*/

	TUint iCacheSize; /**< Number of bytes allocated by all elements in the tree.*/

	};

/**

@return The unique id of the font

*/

inline TUint32 CFontGlyphTree::FontId() const

	{

	return iFontId;

	}

/**

@return The total size of the cache

*/

inline TUint CFontGlyphTree::CacheSize() const

	{

	return iCacheSize;

	}

/**

@param aPtr A pointer to a source buffer of 2 8-bit unsigned integers.

@return The two 8-bit integers combined into a 16-bit integer.

*/

inline TInt16 CFontGlyphTree::Load16(const TUint8* aPtr) 

	{

	return TInt16(aPtr[0]+(aPtr[1]<<8)); 

	}

/**

The class provides an interface for handling image caching and will be maintained by the DirectGDI driver at adaptation level.

Any instance of this class cannot be shared between threads.

*/

NONSHARABLE_CLASS(CFontGlyphImageStorage) : public CBase, 

								public MFontGlyphImageStorage

{

public:

	CFontGlyphImageStorage(TInt aMaxCacheSize);

	TInt PreAllocateImages();

	~CFontGlyphImageStorage();

	// from MFontGlyphImageStorage

	TInt GlyphImage(TUint32 aFontId, TChar aGlyphCode, TGlyphBitmapType aGlyphBitmapType, 

						const TUint8* aGlyphImage, const TSize& aGlyphImageSize, 

						TAny* aImageForeground, TAny* aImageShadow, TAny* aImageOutline);	/**< @internalTechnology*/

	void CleanGlyphImageCache();	/**< @internalTechnology*/

	TInt GlyphCacheSize() const;	/**< @internalTechnology*/

	TInt MaxGlyphCacheSize() const;	/**< @internalTechnology*/

	TInt FontIdInOrder(RArray<TUint32> & aFontListId) const;	/**< @internalTechnology*/

	void EnforceOOMFailure(TBool aEnforce);	/**< @internalTechnology*/

	TInt SetMaxGlyphCacheSize(TInt aMaxCacheSize);	/**< @internalTechnology*/

private:

	void DeletePreAllocatedImages();

	void CleanCacheIfRequired();

private:

	RPointerArray<CFontGlyphTree> iFontTreeList;	/**< Array of all image trees in the cache.*/

	TInt iMaxCacheSize;	/**< Maximum cache size the class can hold.*/

	TInt iCacheSize;	/**< Current total cache size which amounts to cache sizes of all trees in the list .*/

	TGlyphEntry iEntry;	/**< Work member, which will be filled when user requests glyph image.*/

	TGlyphEntryCompound iEntryCompound;	/**< Work member, which will be filled when user requests glyph image.*/

	//for OOM conditions

	TUint8* iForegroundData;

	TUint8* iShadowData;

	TUint8* iOutlineData;

	VGImage iImageForeground;	/**< Pre-allocated image for OOM conditions.*/

	VGImage iImageShadow;	/**< Pre-allocated image for OOM conditions.*/

	VGImage iImageOutline;	/**< Pre-allocated image for OOM conditions.*/

	TSize iImageSize;	/**< Pre-defined image size.*/

	TBool iImagesPreAllocated;	/**< True if all OOM variables were created successfully.*/

#ifdef _DEBUG

	TBool iEnforceOOM;	/**< If true will always try to use pre-allocated images.*/

#endif

};

#endif