--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/fbs/fontandbitmapserver/sfbs/glyphatlas.h Fri Sep 24 16:14:28 2010 +0300
@@ -0,0 +1,185 @@
+// Copyright (c) 2009-2010 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:
+// Font & Bitmap Server Glyph Atlas
+//
+
+#ifndef GLYPHATLAS_H
+#define GLYPHATLAS_H
+
+#include <e32base.h>
+#include <sgresource/sgimage.h>
+#include <fbs.h>
+#include "UTILS.H"
+
+class CGlyphAtlasFontEntry;
+class CGlyphAtlasPage;
+class TGlyphCacheMetrics;
+
+/**
+The Glyph Atlas manages the storing and retrieval of glyphs stored in GPU
+memory as RSgImages.
+
+CGlyphAtlas is the main class which processes requests to add and retrieve
+glyphs. Only one instance of this class will exist throughout the lifetime of
+the Font and Bitmap Server.
+@internalComponent
+*/
+NONSHARABLE_CLASS(CGlyphAtlas) : public CBase
+ {
+friend class CGlyphAtlasTestWrapper;
+public:
+ /**
+ Structure used to pass information required to create a new glyph so that it can
+ be added to the glyph atlas.
+ @internalComponent
+ */
+ class TAddGlyphArgs
+ {
+ public:
+ inline TAddGlyphArgs(const TUint8* aBitmapPointer, TUint aGlyphCode, const TOpenFontCharMetrics& aMetrics)
+ : iBitmapPointer(aBitmapPointer), iGlyphCode(aGlyphCode), iMetrics(&aMetrics) {}
+ public:
+ const TUint8* iBitmapPointer; /**< The address of the bitmap glyph. No ownership.*/
+ TUint iGlyphCode; /**< The glyph code for the glyph being added. No ownership.*/
+ const TOpenFontCharMetrics* iMetrics; /**< The metrics for the glyph being added. No ownership.*/
+ };
+
+public:
+ ~CGlyphAtlas();
+ static CGlyphAtlas* NewL(TInt aMaxCacheSizeInBytes);
+ TInt GetGlyph(const CBitmapFont& aFont, TUint aGlyphCode, TGlyphImageInfo& aGlyphImageInfo);
+ TInt AddGlyph(const CBitmapFont& aFont, const TAddGlyphArgs& aArgs, TGlyphImageInfo& aGlyphImageInfo);
+ void FontReleased(const CBitmapFont& aFont);
+ void MovePageToFront(CGlyphAtlasPage& aPage);
+ TBool DeleteLeastRecentlyUsedPage(TBool aAllowMruPageDeletion);
+ TInt FontCount() const;
+ TInt GlyphCount() const;
+ TInt GlyphCount(const CBitmapFont& aFont) const;
+ void GlyphCacheMetrics(TInt& aSizeInBytes, TInt& aMaxSizeInBytes, TBool& aGpuCacheSizeLimitIsMax);
+ void ReleaseGpuMemory( TInt /*aBytes*/, TInt /*aFlags*/ );
+ void InstateGpuMemory( TInt /*aFlags*/ );
+ void GetGlyphCacheMetrics( TGlyphCacheMetrics& aGlyphCacheMetrics );
+
+private:
+ CGlyphAtlas(TInt aMaxCacheSizeInBytes);
+ void ConstructL();
+ CGlyphAtlasFontEntry* CreateFontEntry(const CBitmapFont& aFont);
+ CGlyphAtlasFontEntry* FindFontEntry(const CBitmapFont& aFont) const;
+ void DeleteFontEntry(CGlyphAtlasFontEntry* aFontEntry);
+ void SwitchGpuCacheSizeLimit();
+ TBool GpuCacheSizeLimitIsMax() const;
+
+private:
+ class TFontEntryMap
+ {
+ public:
+ inline TFontEntryMap(const CBitmapFont* aFont, CGlyphAtlasFontEntry* aEntry)
+ : iFont(aFont),iEntry(aEntry) {}
+ public:
+ const CBitmapFont* iFont;
+ CGlyphAtlasFontEntry* iEntry;
+ };
+private:
+ RSgDriver iSgDriver;
+ TDblQue<CGlyphAtlasPage> iLruPageList; /**< Least-recently used ordered queue (most-recently used at head).*/
+ RArray<TFontEntryMap> iFontEntryArray; /**< Array of font entries maintained in unsigned ordered by font pointer.*/
+ TUint iMaxCacheSizeInBytes; /**< Maximum specialised graphics memory the cache should use. If zero, there is no limit.*/
+ TInt iMaxCacheSizeHigh; /**< The high cach-size threshold.*/
+ TInt iMaxCacheSizeLow; /**< The low cach-size threshold.*/
+ TUint iCacheSizeInBytes; /**< Actual amount of specialised graphics memory used by the entire atlas.*/
+ TBool iGpuCacheSizeLimitIsMax; /**< Is the cache-size limit set to it's maximum value? */
+ };
+
+
+/**
+Each font entry manages the storing and retrieval of glyphs belonging to a font.
+@internalComponent
+*/
+NONSHARABLE_CLASS(CGlyphAtlasFontEntry): public CBase
+ {
+public:
+ CGlyphAtlasFontEntry(const CBitmapFont& aFont, CGlyphAtlas& aGlyphAtlas);
+ ~CGlyphAtlasFontEntry();
+ const CBitmapFont& Font() const;
+ void DeletePage(CGlyphAtlasPage* aPage);
+ TInt GetGlyph(TUint aGlyphCode, TGlyphImageInfo& aGlyphImageInfo);
+ TInt AddGlyph(const CGlyphAtlas::TAddGlyphArgs& aArgs, TGlyphImageInfo& aGlyphImageInfo, TInt& aSizeInBytes);
+ TInt SizeInBytes() const;
+ TBool IsEmpty() const;
+ CGlyphAtlas& GlyphAtlas() const;
+ TInt GlyphCount() const;
+
+private:
+ // Class that handles association between glyph code and page the
+ // image that glyph code resides on. Used in pointer arrays.
+ class TPageMap
+ {
+ public:
+ inline TPageMap(TUint aGlyphCode, CGlyphAtlasPage* aPage)
+ : iGlyphCode(aGlyphCode),iPage(aPage) {}
+ public:
+ TUint iGlyphCode;
+ CGlyphAtlasPage* iPage;
+ };
+private:
+ const CBitmapFont& iFont; /**< The font which the stored glyph belongs to.*/
+ RArray<TPageMap> iPageArray; /**< Array of pages maintained in unsigned ordered by glyph code.*/
+ CGlyphAtlas& iAtlas; /**< The glyph atlas the font entry belongs to.*/
+ TInt iSizeInBytes; /**< The amount of specialised graphics memory used by all owned pages.*/
+ };
+
+
+/**
+Each page in the glyph atlas stores one glyph in one RSgImage.
+@internalComponent
+*/
+NONSHARABLE_CLASS(CGlyphAtlasPage): public CBase
+ {
+friend CGlyphAtlas::CGlyphAtlas(TInt);
+public:
+ CGlyphAtlasPage(CGlyphAtlasFontEntry& aFontEntry);
+ ~CGlyphAtlasPage();
+ TInt AddGlyph(const CGlyphAtlas::TAddGlyphArgs& aArgs, TGlyphImageInfo& aGlyphImageInfo, TInt& aSizeInBytes);
+ void GetGlyph(TUint aGlyphCode, TGlyphImageInfo& aGlyphImageInfo) const;
+ TUint GlyphCodeAt(TInt aIndex) const;
+ TInt GlyphCount() const;
+ CGlyphAtlasFontEntry& FontEntry() const;
+ TInt SizeInBytes() const;
+ void MoveToFirstInQueue(TDblQue<CGlyphAtlasPage>& aList);
+
+private:
+ TDblQueLink iLink;
+ // Data for the stored glyph
+ CGlyphAtlasFontEntry& iFontEntry; /**< The font entry asssociated with the page.*/
+ RSgImage iGlyphImage; /**< The image which contains the stored glyph.*/
+ TInt16 iPosX; /**< The x-coord of the position of the stored glyph within the image.*/
+ TInt16 iPosY; /**< The y-coord of the position of the stored glyph within the image.*/
+ TOpenFontCharMetrics iMetrics; /**< The character metrics for the stored glyph.*/
+ TUint iGlyphCode; /**< The glyph code for the stored glyph.*/
+ TInt iSizeInBytes; /**< The amount of specialised graphics memory used by this page.*/
+ TInt iNumGlyphs; /**< The number of glyphs contained in the page.*/
+ };
+
+
+// If no limit to the size of the glyph atlas cache is desired, this
+// constant must be passed to CGlyphCache::NewL()
+// In this case the cache lower maximum limit, deployed in response to GooM,
+// will be set to KGlyphAtlasLowMemCacheLimitDefault
+const TInt KGlyphAtlasNoCacheLimit = 0;
+const TInt KGlyphAtlasLowMemCacheLimitDivisor = 2;
+const TInt KGlyphAtlasLowMemCacheLimitDefault = 0x40000;
+
+
+#endif // GLYPHATLAS_H
+