graphicsdeviceinterface/gdi/sgdi/FONT.CPP
changeset 0 5d03bc08d59c
child 26 15986eb6c500
child 36 01a6848ebfd7
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graphicsdeviceinterface/gdi/sgdi/FONT.CPP	Tue Feb 02 01:47:50 2010 +0200
@@ -0,0 +1,1591 @@
+// Copyright (c) 1998-2009 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:
+//
+
+#include <gdi.h>
+#include <openfont.h>
+#include "GlyphSel.h"
+#include "FontThai.h"
+#include "FontArabic.h"
+#include "FontIndic.h"
+#include "GDIPANIC.h"
+#include "glyphsample.h"
+#include "gdiinline.inl"
+#include "gdistructs.h"
+#include "gdiconsts.h"
+
+/**
+ Names holds the types & data associated with the glyph selection
+ algorithm in CFont::GetCharacterPosition().
+@internalComponent
+*/
+namespace GlyphSelection
+    {
+
+    typedef TBool (*ProcessFunc)(TGlyphSelectionState& aGss, RShapeInfo&);
+
+    /**
+     This structure defines the fields present in each row of the GlyphTable
+     datat table below. 
+    @internalComponent
+    */
+    struct TTableEntry 
+    	{
+    	TUint            iLow;
+    	TUint            iHigh;
+    	ProcessFunc	 iProcessFunc;
+    	};
+
+    /**
+     This table encodes the Unicode character ranges and the glyph selector
+     classes to be used for each character range when processing characters
+     into glyph clusters in CFont::GetCharacterPosition().
+     New glyph selection classes must make sure they are listed in this 
+     table to ensure they are invoked as required.
+     A '0' iProcessFunc entry tells the algorithm to skip the character.
+    @internalComponent
+    */
+    static const TTableEntry Table[] =
+    	{
+    	//    iLow,     iHigh,    iProcessFunc
+    		{ 0x0000,   0x00AC,   GlyphSelector_Default::Process},
+    		{ 0x00AD,   0x00AD,   GlyphSelector_SoftHyphen::Process},
+    		{ 0x00AE,   0x05FF,   GlyphSelector_Default::Process},
+    		{ 0x0600,   0x06FF,   GlyphSelector_Arabic::Process},
+    		{ 0x0700,   0x08FF,   GlyphSelector_Default::Process},
+    		{ 0x0900,   0x0970,   GlyphSelector_Devanagari::Process},
+    		{ 0x0980,   0x09FF,   GlyphSelector_Bengali::Process},
+    		{ 0x0A00,   0x0A7F,   GlyphSelector_Gurmukhi::Process},
+    		{ 0x0A80,   0x0AFF,   GlyphSelector_Gujarati::Process},
+    		{ 0x0B80,   0x0BFF,   GlyphSelector_Tamil::Process},
+    		{ 0x0C00,	0x0C7F,   GlyphSelector_Telugu::Process},
+    		{ 0x0C80,	0x0CFF,   GlyphSelector_Kannada::Process},
+    		{ 0x0D00,   0x0D7F,   GlyphSelector_Malayalam::Process},    		
+    		{ 0x0D80,   0x0DFF,   GlyphSelector_Default::Process},
+    		{ 0x0E00,   0x0E32,   GlyphSelector_Thai::Process},
+    		{ 0x0E33,   0x0E33,   GlyphSelector_ThaiSaraAm::Process},
+    		{ 0x0E34,   0x0E7F,   GlyphSelector_Thai::Process},
+    		{ 0x0E80,   0x200B,   GlyphSelector_Default::Process},
+    		{ 0x200C,   0x200F,   0},
+    		{ 0x2010,   0x2029,   GlyphSelector_Default::Process},
+    		{ 0x202A,   0x202E,   0},
+    		{ 0x202F,   0xFFFD,   GlyphSelector_Default::Process},
+    		{ 0xFFFE,   0xFFFF,   0},
+    		{ 0x10000,	0x10FFFF, GlyphSelector_Default::Process},
+    		{0xFFFFFFFF,0xFFFFFFFF, 0}
+    	};
+    }
+
+/** Find appropriate processor function for the given character.
+@param aChar Character for processing.
+@return processor function or 0 if the character is to be skipped.
+@internalComponent */
+GlyphSelection::ProcessFunc CharacterToProcessFunction(TInt aChar)
+	{
+	for (const GlyphSelection::TTableEntry* glyphSel = GlyphSelection::Table;
+		glyphSel->iLow != 0xFFFFFFFF; glyphSel++)
+		{
+		if ((glyphSel->iLow <= aChar) && (aChar <= glyphSel->iHigh))
+			return glyphSel->iProcessFunc;
+		}
+	return 0;
+	}
+
+/**
+@internalTechnology For use by TFontStyle/TOpenFontSpec.
+*/
+EXPORT_C TBool FontEffect::IsEffectOn(TEffect aEffect, TUint32 aFontEffect)
+	{
+	return aEffect & aFontEffect;
+	}
+
+/**
+@internalTechnology For use by TFontStyle/TOpenFontSpec.
+*/
+EXPORT_C void FontEffect::SetEffect(TEffect aEffect, TBool aOn, TUint32& aFontEffect)
+	{
+	if (aOn)
+		aFontEffect |= aEffect;
+	else
+		aFontEffect &= ~aEffect;
+	}
+
+
+//
+// TFontStyle
+//
+
+/** Default C++ constructor. */
+EXPORT_C TFontStyle::TFontStyle():
+	iFlags(0), iReserved1(0), iReserved2(0)
+	{}
+
+
+/** Constructs a TFontStyle object with the specified attributes.
+@param aPost The posture attribute. 
+@param aStrWgt The stroke weight attribute. 
+@param aPrintPos The print position attribute. */
+EXPORT_C TFontStyle::TFontStyle(TFontPosture aPostr,TFontStrokeWeight aWgt,TFontPrintPosition aPos):
+	iFlags(0), iReserved1(0), iReserved2(0)
+	{
+	if (aPostr == EPostureItalic)
+		{
+		iFlags |= EItalic;
+		}
+	if (aWgt == EStrokeWeightBold)
+		{
+		iFlags |= EBold;
+		}
+	if (aPos == EPrintPosSuperscript)
+		{
+		iFlags |= ESuper;
+		}
+	else if (aPos == EPrintPosSubscript)
+		{
+		iFlags |= ESub;
+		}
+	}
+
+
+EXPORT_C void TFontStyle::InternalizeL(RReadStream& aStream)
+/** Internalises a font style from a read stream.
+
+The presence of this function means that the standard templated operator>>() 
+(defined in s32strm.h) is available to internalise objects of this class.
+
+@param aStream The stream from which the font style is to be internalised 
+@leave KErrNoMemory If there is a problem reading from the stream.
+If internalisation causes an out of memory error. */
+	{
+	iFlags = aStream.ReadUint32L();
+	}
+
+
+EXPORT_C void TFontStyle::ExternalizeL(RWriteStream& aStream) const
+/** Externalises the font style to a write stream.
+
+The presence of this function means that the standard templated operator<<() 
+(defined in s32strm.h) is available to externalise objects of this class.
+
+@param aStream The stream to which the font style is to be externalised.
+@leave KErrNoMemory This function may leave, if the write action causes the 
+stream's resources to be exhausted. */
+	{
+	aStream.WriteUint32L(iFlags);
+	}
+
+
+EXPORT_C TFontPosture TFontStyle::Posture() const
+/** Gets the posture attribute.
+
+@return The font style's posture. */
+	{
+	if(iFlags&EItalic) return(EPostureItalic);
+	return(EPostureUpright);
+	}
+
+
+EXPORT_C TFontStrokeWeight TFontStyle::StrokeWeight() const
+/** Gets the stroke weight attribute.
+
+@return The font style's stroke weight. */
+	{
+	if(iFlags&EBold) return(EStrokeWeightBold);
+	return(EStrokeWeightNormal);
+	}
+
+
+EXPORT_C TFontPrintPosition TFontStyle::PrintPosition() const
+/** Gets the print position attribute.
+
+@return The font style's print position. */
+	{
+	if((iFlags&ESuper) && !(iFlags&ESub)) return(EPrintPosSuperscript);
+	else if((iFlags&ESub) && !(iFlags&ESuper)) return(EPrintPosSubscript);
+	return(EPrintPosNormal);
+	}
+
+
+EXPORT_C void TFontStyle::SetPosture(TFontPosture aPosture)
+/** Sets the posture attribute.
+
+@param aPosture The posture to be set. */
+	{
+	if(aPosture==EPostureItalic) iFlags|=EItalic;
+	else iFlags&=~EItalic;
+	}
+
+
+EXPORT_C void TFontStyle::SetStrokeWeight(TFontStrokeWeight aStrokeWeight)
+/** Sets the stroke weight attribute.
+
+@param aStrokeWeight The stroke weight to be set. */
+	{
+	if(aStrokeWeight==EStrokeWeightBold) iFlags|=EBold;
+	else iFlags&=~EBold;
+	}
+
+
+EXPORT_C void TFontStyle::SetPrintPosition(TFontPrintPosition aPrintPosition)
+/** Sets the print position attribute.
+
+@param aPrintPosition The print position to be set. */
+	{
+	switch(aPrintPosition)
+		{
+		case EPrintPosSuperscript:
+			{
+			iFlags|=ESuper;
+			iFlags&=~ESub;
+			break;
+			}
+		case EPrintPosSubscript:
+			{
+			iFlags&=~ESuper;
+			iFlags|=ESub;
+			break;
+			}
+		default:
+			{
+			iFlags&=~ESuper;
+			iFlags&=~ESub;
+			}
+	 	}
+	}
+
+/** Gets the font effects flags.
+@publishedAll
+@released
+@return The font effects flags.
+@see TFontStyle::SetEffects()
+*/
+EXPORT_C TUint32 TFontStyle::Effects() const
+	{
+	return 0xFFF0 & iFlags;
+	}
+
+/** Checks if a font effect is on.
+@publishedAll
+@released
+@return True represents the specified font effect is on, otherwise off.
+@param aEffect The font effect to be checked.
+@see TFontStyle::SetEffects()
+*/
+EXPORT_C TBool TFontStyle::IsEffectOn(FontEffect::TEffect aEffect) const
+	{
+	return FontEffect::IsEffectOn(aEffect, iFlags);
+	}
+
+/** Sets the font effects flags.
+@publishedAll
+@released
+@param aEffect The font effects flags to be set.
+@see TFontStyle::Effects()
+*/
+EXPORT_C void TFontStyle::SetEffects(TUint32 aEffects)
+	{
+	iFlags &= 0xFFFF000F;
+	iFlags |= 0xFFF0 & aEffects;
+	}
+
+/** Sets a font effect to the given state.
+@publishedAll
+@released
+@param aEffect The font effect to be set.
+@param aOn True represents on, otherwise off.
+@see TFontStyle::IsEffectOn()
+*/
+EXPORT_C void TFontStyle::SetEffects(FontEffect::TEffect aEffect, TBool aOn)
+	{
+	FontEffect::SetEffect(aEffect, aOn, iFlags);
+	}
+
+/** Compares a font style for equality.
+@publishedAll
+@released
+@param aFontStyle The font style to be compared with this font style.
+@return ETrue, if this TFontStyle is equal to aFontStyle, EFalse, otherwise.
+*/
+EXPORT_C TBool TFontStyle::operator==(const TFontStyle& aFontStyle) const
+	{
+	return iFlags == aFontStyle.iFlags;
+	}
+
+//
+// TFontSpec
+//
+EXPORT_C TFontSpec::TFontSpec():
+	iTypeface(),
+	iHeight(0),
+	iFontStyle()
+/** Default constructor.
+
+The object's font style is set to the default: EPostureUpright, EStrokeWeightNormal, 
+and EPrintPosNormal. */
+	{}
+
+
+EXPORT_C TFontSpec::TFontSpec(const TDesC& aTypefaceName,TInt aHeight):
+	iTypeface(),
+	iHeight(aHeight),
+	iFontStyle(EPostureUpright,EStrokeWeightNormal,EPrintPosNormal)
+/** Constructs a TFontSpec object with the specified typeface and height. 
+
+The object's font style is set to the default: EPostureUpright, EStrokeWeightNormal, 
+and EPrintPosNormal.
+
+@param aTypefaceName The name of the typeface (e.g. "Roman"). 
+@param aHeight The height of the typeface, in twips. */
+	{
+	iTypeface.iName=aTypefaceName;
+	}
+
+
+EXPORT_C TBool TFontSpec::operator==(const TFontSpec& aFontSpec) const
+/** Compares this font specification with another.
+@param aFontSpec The font specification to be compared with this one. 
+@return ETrue, if the TFontSpecs are identical, EFalse otherwise.
+*/
+	{
+	return
+		iHeight		== aFontSpec.iHeight &&
+		iFontStyle	== aFontSpec.iFontStyle &&
+		iTypeface	== aFontSpec.iTypeface;
+	}
+
+
+EXPORT_C void TFontSpec::InternalizeL(RReadStream& aStream)
+/** Internalises a font specification from a read stream.
+
+The presence of this function means that the standard templated operator>>() 
+(defined in s32strm.h) is available to internalise objects of this class.
+
+@param aStream The stream from which the font specification is to be internalised.
+@leave KErrNoMemory If internalisation causes an out of memory error. */
+	{
+	iTypeface.InternalizeL(aStream);
+	iHeight=aStream.ReadUint16L();
+	iFontStyle.InternalizeL(aStream);
+	}
+
+
+EXPORT_C void TFontSpec::ExternalizeL(RWriteStream& aStream) const
+/** Externalises the font specification to a write stream.
+
+The presence of this function means that the standard templated operator<<() 
+(defined in s32strm.h) is available to externalise objects of this class.
+
+@param aStream The stream to which the font specification is to be externalised 
+
+@leave KErrNoMemory If the write action causes the stream's resources to be 
+exhausted. */
+	{
+	iTypeface.ExternalizeL(aStream);
+	aStream.WriteUint16L(iHeight);
+	iFontStyle.ExternalizeL(aStream);
+	}
+
+EXPORT_C void TFontSpec::SetScriptTypeForMetrics(TLanguage aLanguage)
+/** Specifies the script with which font metrics calculation will be based on.
+@param aLanguage The language used to derive the required script.
+@publishedAll
+@released
+*/
+	{
+	iTypeface.SetScriptTypeForMetrics(aLanguage);
+	}
+
+EXPORT_C TInt TFontSpec::ScriptTypeForMetrics() const
+/** Returns the script with which font metrics calculation will be based on.
+@internalTechnology
+*/
+	{
+	return iTypeface.ScriptTypeForMetrics();
+	}
+
+//
+// TTypeface
+//
+static const TInt KTTypefaceBitsNumAttrib = 3;
+static const TInt KTTypefaceBitsNumScript = 4;
+static const TInt KTTypefaceMaskAttrib = (1 << KTTypefaceBitsNumAttrib) - 1;
+static const TInt KTTypefaceMaskScript = ((1 << KTTypefaceBitsNumScript) - 1) << KTTypefaceBitsNumAttrib;
+EXPORT_C TTypeface::TTypeface():
+	iName(),
+	iFlags(0)
+/** Default C++ constructor. */
+	{}
+
+/**
+@internalComponent
+*/
+void TTypeface::ResetAttributes()
+	{
+	iFlags &= KTTypefaceMaskScript;
+	}
+
+/**
+@internalComponent
+*/
+void TTypeface::ResetScriptType()
+	{
+	iFlags &= KTTypefaceMaskAttrib;
+	}
+
+EXPORT_C void TTypeface::InternalizeL(RReadStream& aStream)
+/** Internalises a typeface from a read stream. 
+
+The presence of this function means that the standard templated operator>>() 
+(defined in s32strm.h) is available to internalise objects of this class.
+
+@param aStream Stream from which the typeface is to be internalised. */
+	{
+	TBuf<KMaxTypefaceNameLength> tempname;
+	aStream >> tempname;
+	new(&iName) TBufC<KMaxTypefaceNameLength>(tempname);
+	iFlags = aStream.ReadInt8L();
+	}
+
+
+EXPORT_C void TTypeface::ExternalizeL(RWriteStream& aStream) const
+/** Externalises a typeface to a write stream. 
+
+The presence of this function means that the standard templated operator<<() 
+(defined in s32strm.h) is available to externalise objects of this class.
+
+@param aStream The stream to which the typeface is to be externalised. */
+	{
+	aStream << iName;
+	aStream.WriteInt8L(static_cast<TInt8>(iFlags));
+	}
+
+
+EXPORT_C TBool TTypeface::operator==(const TTypeface& aTypeface) const
+/** Compares two typefaces for equality.
+
+@param aTypeface The typeface to be compared with. 
+@return ETrue, if this TTypeface is equal to aTypeface, otherwise EFalse. */
+	{
+	return
+		iFlags == aTypeface.iFlags &&
+		iName == aTypeface.iName;
+	}
+
+EXPORT_C void TTypeface::SetAttributes(TInt aAttributes)
+/** Set the combination of attributes for this typeface.
+
+@param aAttributes A bitmap defining the combination of attributes. */
+	{
+	ResetAttributes();
+	iFlags |= KTTypefaceMaskAttrib & aAttributes & (EProportional | ESerif | ESymbol);
+	}
+
+
+EXPORT_C void TTypeface::SetIsProportional(TBool aIsProportional)
+/** Sets the typeface's proportional attribute.
+
+@param aIsProportional ETrue if the typeface is a proportional typeface, otherwise 
+EFalse. */
+	{
+	if (aIsProportional)
+		{
+		iFlags |= EProportional;
+		}
+	else
+		{
+		iFlags &= ~EProportional;
+		}
+	}
+
+
+EXPORT_C void TTypeface::SetIsSerif(TBool aIsSerif)
+/** Sets the typeface's serif attribute.
+
+@param aIsSerif ETrue if the typeface is a serif typeface, otherwise EFalse. */
+	{
+	if (aIsSerif)
+		{
+		iFlags |= ESerif;
+		}
+	else
+		{
+		iFlags &= ~ESerif;
+		}
+	}
+
+
+EXPORT_C void TTypeface::SetIsSymbol(TBool aIsSymbol)
+/** Sets the typeface's symbol attribute.
+
+@param aIsSymbol ETrue if the typeface is a symbol typeface, otherwise EFalse. */
+	{
+	if (aIsSymbol)
+		{
+		iFlags |= ESymbol;
+		}
+	else
+		{
+		iFlags &= ~ESymbol;
+		}
+	}
+
+
+EXPORT_C TInt TTypeface::Attributes() const
+/** Gets the combination of attributes of the typeface.
+
+@return The combination of attributes of the typeface. */
+	{
+	return KTTypefaceMaskAttrib & iFlags;
+	}
+
+
+EXPORT_C TBool TTypeface::IsProportional() const
+/** Gets the typeface's proportional attribute.
+
+@return ETrue if the typeface is proportional, EFalse otherwise. */
+	{
+	return KTTypefaceMaskAttrib & iFlags & EProportional;
+	}
+
+
+EXPORT_C TBool TTypeface::IsSerif() const
+/** Gets the typeface's serif attribute.
+
+@return ETrue if the typeface is a serif typeface, EFalse otherwise */
+	{
+	return KTTypefaceMaskAttrib & iFlags & ESerif;
+	}
+
+
+EXPORT_C TBool TTypeface::IsSymbol() const
+/** Gets the typeface's symbol attribute.
+
+@return ETrue if the typeface is a symbol typeface, EFalse otherwise */
+	{
+	return KTTypefaceMaskAttrib & iFlags & ESymbol;
+	}
+
+
+/** Specifies the script with which font metrics calculation will be based on.
+@param aLanguage The language used to derive the required script.
+@internalTechnology
+*/
+EXPORT_C void TTypeface::SetScriptTypeForMetrics(TLanguage aLanguage)
+	{
+	SetScriptTypeForMetrics(GlyphSample::TLanguage2TScript(aLanguage));
+	}
+
+/** Specifies the script with which font metrics calculation will be based on.
+@param aScript The script.
+@internalTechnology
+*/
+EXPORT_C void TTypeface::SetScriptTypeForMetrics(TInt aScript)
+	{
+	ResetScriptType();
+	iFlags |= KTTypefaceMaskScript & (aScript << KTTypefaceBitsNumAttrib);
+	}
+
+/** Gets the script with which font metrics calculation will be based on.
+@return The script.
+@internalTechnology
+*/
+EXPORT_C TInt TTypeface::ScriptTypeForMetrics() const
+	{
+	return (KTTypefaceMaskScript & iFlags) >> KTTypefaceBitsNumAttrib;
+	}
+
+
+//
+// CFont
+//
+
+/** Default destructor. */
+EXPORT_C CFont::~CFont()
+	{}
+
+_LIT(KGdiZeroCharacter,"0");
+
+/** Gets the width of the zero character of this font in pixels. 
+
+This function is provided as the "0" character is roughly the average width 
+of the characters of any font.
+
+@return The width of the "0" character, in pixels. */
+EXPORT_C TInt CFont::WidthZeroInPixels() const
+	{
+	return(TextWidthInPixels(KGdiZeroCharacter));
+	}
+
+
+/** Gets the font descent in pixels.
+It is defined to be HeightInPixels() minus AscentInPixels().
+Note that this deprecated function is replaced by the new @c FontMaxDescent()
+or in some cases @c FontStandardDescent().
+
+@return The font descent in pixels.
+@see FontStandardDescent() 
+@see FontMaxDescent()
+@deprecated */
+EXPORT_C TInt CFont::DoDescentInPixels() const
+	{
+	return HeightInPixels() - AscentInPixels();
+	}
+
+
+/** Checks to see if the pen position needs to be included in the bounds
+calculation for purposes of considering side-bearings in the line break point
+
+@param aInput The input block. Contains the check flag and maxbounds.
+@param aPenPos The current value of the pen position.
+@param aBoundsBR Bottom-right bounds value.
+@param aBoundsTL Top-left bounds value.
+@return Whether or not MaxBounds has been exceeded
+*/
+LOCAL_C TBool BoundsExceeded(const CFont::TMeasureTextInput& aInput,
+	const TInt& aPenPos, TInt& aBoundsBR, TInt& aBoundsTL)
+	{
+	if (aInput.iFlags & CFont::TMeasureTextInput::EFIncludePenPositionInBoundsCheck)
+		{
+		if (aInput.iFlags & CFont::TMeasureTextInput::EFVisualOrderRightToLeft)
+			{
+			aBoundsTL = Min(aBoundsTL, aPenPos);
+			}
+		else
+			{
+		 	aBoundsBR = Max(aBoundsBR, aPenPos);
+			}
+		}
+ 	return (aBoundsBR - aBoundsTL > aInput.iMaxBounds);
+	}
+
+
+/** Text measurement function.
+
+This is a powerful text measurement function underlying all the
+other text measurement functions. It takes optional input and output
+parameter blocks, which may be null, and returns the advance 
+width (change in pen position when drawn horizontally) of the text, or the advance
+height, if the text is drawn vertically.
+
+Some of the functions that can be performed using this
+function are listed below. Many of them are used by the Text Views
+API to do its typographic layout.
+- Get the advance width or advance height (return value).
+The advance width is the amount by which the pen advances when drawing
+the text horizontally, while the advance height is the amount by which 
+the pen advances when drawing the text vertically.
+- Measure some text in context, so that shaping behaviour
+(e.g. in Arabic) can be affected by what comes before and after the
+text. Do this using TMeasureTextInput::iStartInputChar and 
+TMeasureTextInput::iEndInputChar to tell the function where to start and end 
+in the supplied descriptor.
+- Determine how much text fits a given size by setting 
+TMeasureTextInput::iMaxAdvance or TMeasureTextInput::iMaxBounds. 
+- Specify letter spacing and word spacing using TMeasureTextInput::iCharJustNum,
+TMeasureTextInput::iCharJustExcess, 
+TMeasureTextInput::iWordJustNum and 
+TMeasureTextInput::iWordJustExcess. 
+- Get the number of characters drawn in TMeasureTextOutput::iChars 
+when applying the various constraints in TMeasureTextInput. 
+- Get the number of glyphs drawn in TMeasureTextOutput::iGlyphs. 
+- Get the number of groups (formed by ligation or diacritic placement) in 
+TMeasureTextOutput::iGroups. Groups are units of cursor
+movement: the cursor hops over a character-plus-accent group or an
+Arabic or other ligature in one go.
+- Get the number of word spaces in TMeasureTextOutput::iSpaces. 
+- Get the bounds of the inked-in pixels in TMeasureTextOutput::iBounds. 
+- Get the size of the biggest glyph that would be drawn in TMeasureTextOutput::iMaxGlyphSize.
+
+@param aText The text to be measured.
+@param aInput The input block. This may be NULL.
+@param aOutput The output block. This may be NULL.
+@return The advance width if the text is drawn horizontally or the advance 
+height if the text is drawn vertically. 
+
+@panic GDI 1 In debug builds only, if TMeasureTextInput::iStartInputChar is negative.
+*/
+EXPORT_C TInt CFont::MeasureText(const TDesC& aText,const TMeasureTextInput* aInput,TMeasureTextOutput* aOutput) const
+	{
+	TMeasureTextInput input;
+	if (aInput)
+		input = *aInput;
+	if (aOutput)
+		{
+		Mem::FillZ(aOutput,sizeof(*aOutput));
+		aOutput->iChars = input.iStartInputChar;
+		}
+	TPositionParam param;
+	param.iDirection = input.iDirection;
+ 
+ 	TBool vertical = param.iDirection == EVertical;
+ 	TBool penMovesLeft = EFalse;
+ 	if (input.iFlags & TMeasureTextInput::EFVisualOrderRightToLeft)
+ 		{
+ 		if (!vertical)
+ 			penMovesLeft = ETrue;
+ 		param.iFlags |= TPositionParam::EFLogicalOrder;
+ 		}
+ 	else if (!(input.iFlags & TMeasureTextInput::EFVisualOrder))
+   		param.iFlags |= TPositionParam::EFLogicalOrder;
+
+
+	param.iText.Set(aText);
+
+	int advance = 0;
+	int groups = 0;
+	int spaces = 0;
+	param.iPosInText = input.iStartInputChar;
+	int end_char = Min(aText.Length(),input.iEndInputChar);
+	TRect bounds;
+	// Total advance if pen is moving left. Positive.
+ 	TInt rightToLeftAdvance = 0;
+	// Shaping information of the text
+	RShapeInfo shapeInfo;
+	while (param.iPosInText < end_char)
+		{
+		if (!GetCharacterPosition2(param, shapeInfo))
+			{
+			if (aOutput)
+				aOutput->iChars = param.iPosInText;
+			continue;
+			}
+
+		int new_advance = vertical ? param.iPen.iY : param.iPen.iX;
+		if (input.iCharJustExcess != 0)
+			new_advance += CGraphicsContext::JustificationInPixels(input.iCharJustExcess,input.iCharJustNum,groups,1);
+		groups++;
+		// Allow justification to occur at spaces
+		if (param.iOutput[0].iCode == 0x0020)
+			{
+			if (input.iWordJustExcess != 0)
+				new_advance += CGraphicsContext::JustificationInPixels(input.iWordJustExcess,input.iWordJustNum,spaces,1);
+			spaces++;
+			}
+		if (vertical)
+			param.iPen.iY = new_advance;
+		else
+			param.iPen.iX = new_advance;
+		
+		if (penMovesLeft)
+ 			{
+ 			// If the pen is moving left, we will begin each cluster at (0,0)
+ 			// and shift the bounds to the right to compensate.
+ 			bounds.iTl.iX += param.iPen.iX;
+ 			bounds.iBr.iX += param.iPen.iX;
+ 			bounds.iTl.iY += param.iPen.iY;
+ 			bounds.iBr.iY += param.iPen.iY;
+ 			rightToLeftAdvance += param.iPen.iX;
+ 			new_advance = rightToLeftAdvance;
+ 			param.iPen.iX = 0;
+ 			param.iPen.iY = 0;
+ 			}
+
+		if (aInput || aOutput)
+			{
+			const TPositionParam::TOutput* output = param.iOutput;
+			for (int i = 0; i < param.iOutputGlyphs; i++, output++)
+				{
+				//if (!output->iBounds.IsEmpty()) -- optimized to:
+				if (output->iBounds.iTl.iX != output->iBounds.iBr.iX
+					|| output->iBounds.iTl.iY != output->iBounds.iBr.iY)
+					{
+					if (aOutput)
+						{
+						// increase iMaxGlyphSize if either dimension smaller than
+						// current glyph
+						TInt boundsDim = output->iBounds.iBr.iX - output->iBounds.iTl.iX;
+						aOutput->iMaxGlyphSize.iWidth = aOutput->iMaxGlyphSize.iWidth < boundsDim?
+							boundsDim : aOutput->iMaxGlyphSize.iWidth;
+						boundsDim = output->iBounds.iBr.iY - output->iBounds.iTl.iY;
+						aOutput->iMaxGlyphSize.iHeight = aOutput->iMaxGlyphSize.iHeight < boundsDim?
+							boundsDim : aOutput->iMaxGlyphSize.iHeight;
+						}
+					//bounds.BoundingRect(output->iBounds); -- optimized to:
+					if (output->iBounds.iTl.iX < bounds.iTl.iX)
+						bounds.iTl.iX = output->iBounds.iTl.iX;
+					if (bounds.iBr.iX < output->iBounds.iBr.iX)
+						bounds.iBr.iX = output->iBounds.iBr.iX;
+					if (output->iBounds.iTl.iY < bounds.iTl.iY)
+						bounds.iTl.iY = output->iBounds.iTl.iY;
+					if (bounds.iBr.iY < output->iBounds.iBr.iY)
+						bounds.iBr.iY = output->iBounds.iBr.iY;
+					}
+				}
+
+			// Would any limits be exceeded by adding this group?
+			if (param.iPosInText > end_char)
+				break;
+			if (new_advance > input.iMaxAdvance)
+				break;
+			if (vertical)
+				{
+				if (BoundsExceeded(input, param.iPen.iY, bounds.iBr.iY, bounds.iTl.iY))
+					break;
+				}
+			else
+				{
+				if (BoundsExceeded(input, param.iPen.iX, bounds.iBr.iX, bounds.iTl.iX))
+					break;
+				}
+
+			if (aOutput)
+				{
+				aOutput->iChars = param.iPosInText;		// should this not be aOutput->iChars = param.iPosInText - input.iShartInputChar;?
+				aOutput->iGlyphs += param.iOutputGlyphs;
+				aOutput->iGroups = groups;
+				aOutput->iSpaces = spaces;
+				aOutput->iBounds = bounds;
+				}
+			}
+
+		advance = new_advance;
+		}
+	if(shapeInfo.IsOpen())
+		shapeInfo.Close();
+	return advance;
+	}
+
+// These 3 functions should probably be moved to E32/Euser as part of TChar or
+// similar as there seem to be several local copies of similar functions in
+// various OS modules so we should remove duplication
+
+TUint16 HighSurrogate(TUint aCode)
+	{
+	GDI_ASSERT_DEBUG(aCode  > 0xFFFF, EGdiPanic_InvalidInputParam);
+	return STATIC_CAST(TUint16, 0xD7C0 + (aCode >> 10));
+	}
+	
+TUint16 LowSurrogate(TUint aCode)
+	{
+	GDI_ASSERT_DEBUG(aCode  > 0xFFFF, EGdiPanic_InvalidInputParam);
+	return STATIC_CAST(TUint16, 0xDC00 | (aCode & 0x3FF));
+	}
+	
+TUint CombineSurrogates(TUint aHighSurrogate, TUint aLowSurrogate)
+	{
+	GDI_ASSERT_DEBUG((0xD800 == (aHighSurrogate & 0xF800)), EGdiPanic_InvalidInputParam);
+	GDI_ASSERT_DEBUG((0xD800 == (aHighSurrogate & 0xFC00)), EGdiPanic_InvalidInputParam);
+	GDI_ASSERT_DEBUG((0xDC00 == (aLowSurrogate & 0xFC00)), EGdiPanic_InvalidInputParam);
+	return ((aHighSurrogate - 0xD7F7) << 10) + aLowSurrogate;
+	}
+
+
+/** Overridable function innards of GetCharacterPosition and
+GetCharacterPosition2. It is generally not useful to override this function.
+@publishedAll
+@see GetCharacterPosition
+@see GetCharacterPosition2
+*/
+EXPORT_C TBool CFont::DoGetCharacterPosition(TPositionParam& aParam) const
+	{
+	RShapeInfo shapeInfo;
+	TBool r = GetCharacterPosition2(aParam, shapeInfo);
+	if (shapeInfo.IsOpen())
+		shapeInfo.Close();
+	return r;
+	}
+
+// Find the script (and hence the correct process function) that any punctuation or digit may belong to
+LOCAL_C GlyphSelection::ProcessFunc FindContextualProcessFunc(RShapeInfo& aShapeInfo, const TGlyphSelectionState aGss)
+	{
+	GlyphSelection::ProcessFunc processFunc = CharacterToProcessFunction(aGss.iCodeChar);
+	GlyphSelection::ProcessFunc contextProcessFunc = (GlyphSelection::ProcessFunc)aShapeInfo.GetContext();
+	
+	// If context or prevCode is NULL, use processFunc,
+	// else use function of context or prevCode
+	if ((aGss.iCodeChar.IsDigit() || aGss.iCodeChar.IsPunctuation()) && !QuoteOrBracketPair(aGss.iCodeChar) && processFunc!=GlyphSelector_SoftHyphen::Process)
+		{
+		// If context is not set, check the previous char for context.
+		if (contextProcessFunc == NULL)
+			{
+			if (aGss.iParam.iPosInText > 0)
+				{
+				TChar prevCode = aGss.iText.Get(-1);
+				GlyphSelection::ProcessFunc prevProcessFunc = CharacterToProcessFunction(prevCode);
+				if (prevProcessFunc != NULL && (prevCode.IsAlpha() || prevProcessFunc != GlyphSelector_Default::Process))
+					{
+					aShapeInfo.SetContext((TAny *)prevProcessFunc);
+					return prevProcessFunc;
+					}
+				}
+			} 
+		else 
+			return contextProcessFunc;
+		
+		return processFunc;
+		}
+	
+	// set the context with current processFunc only if current char is not ignored for context.
+ 	if (processFunc != NULL && (aGss.iCodeChar.IsAlpha() || processFunc != GlyphSelector_Default::Process))
+ 			aShapeInfo.SetContext((TAny *)processFunc);
+ 	return processFunc;
+	}
+
+/** Takes Unicode text and produces the glyph cluster for the first character
+in that text plus any combining mark characters, or for the first indic
+syllable. It is responsible for contextual glyph selection, ligature creation
+and diacritic placement.
+
+@param aParam
+	The input/output parameter of the text/glyph data for the algorithm.
+@param aShapeInfo
+	The function will cache "shaped" text (e.g. complex scripts such as
+	Devanagari) here. aShapeInfo must be freshly-constructed or closed for each
+	new piece of text in aParam.iText. If aParam.iText is unchanged between
+	calls, aShapeInfo should be passed back in unchanged as well.
+@return
+	ETrue if glyphs for supplied text have been produced, EFalse in failure.
+@see CFont::TPositionParam
+@publishedAll
+@released */
+EXPORT_C TBool CFont::GetCharacterPosition2(TPositionParam& aParam, RShapeInfo& aShapeInfo) const
+	{
+	GDI_ASSERT_DEBUG(aParam.iPosInText>=0, EGdiPanic_InvalidInputParam);
+	GDI_ASSERT_DEBUG(aParam.iText.Ptr(), EGdiPanic_InvalidInputParam);
+
+	aParam.iOutputGlyphs = 0;
+	TInt textLen = aParam.iText.Length();
+	TBool outputOk = ETrue;
+	TPoint penCopy = aParam.iPen;
+
+	// Verify input parameters are sane
+	if (aParam.iPosInText >= textLen)
+		return EFalse;
+
+	// Setup glyph selection algorithm data
+	TUtf32Iterator textIter(aParam.iText.Ptr(), aParam.iText.Ptr()+textLen, aParam.iPosInText);
+	if (textIter.AtEnd())
+		{
+		aParam.iPosInText = textIter.LengthToStart();
+		return outputOk;
+		}
+
+	// Process each character in the text in turn until we reach the end of
+	// the iterator, the next base (non-mark/combining) character or reach
+	// the limit in a glyph cluster.
+	GlyphSelection::ProcessFunc firstProcessFn = 0;
+	TGlyphSelectionState gss(textIter, this, aParam);
+	do
+		{
+		// Retrieve character info for processing.
+		gss.iCodePt = gss.iCodeChar = textIter.Get();
+		gss.iCombCls = gss.iCodeChar.GetCombiningClass();
+		gss.iCats = gss.iCodeChar.GetCategory();
+		gss.iClusterState = TGlyphSelectionState::EGClusterNotComplete;
+		gss.iPen = TGlyphSelectionState::EPenAdvance_No;
+
+		// Find the correct processesing function for the script being used.
+		// If gss.iCodePt is a strongly directional character, then simply map it in TTableEntry Table[]
+		// and use the returned process function pointer.
+		// If gss.iCodePt is a punctuation or a digit, then use a context character in the text (if
+		// available) to find the contextual script being rendered and use its process function pointer.
+		GlyphSelection::ProcessFunc processFn = FindContextualProcessFunc(aShapeInfo, gss);
+
+		if (!firstProcessFn)
+			firstProcessFn = processFn;
+
+		if (processFn)
+			{
+			if (firstProcessFn == processFn)
+				outputOk = processFn(gss, aShapeInfo);
+			else
+				break;
+			}
+		else
+			{
+			// Table entry blank, unicode char to be skipped
+			outputOk = ETrue;
+			textIter.Next();
+			gss.iClusterState = 
+				(!textIter.AtEnd() &&
+				((textIter.Get().GetCategory() & 0xF0) 
+				== TChar::EMarkGroup)) ?
+					TGlyphSelectionState::EGClusterNotComplete : TGlyphSelectionState::EGClusterComplete;
+			}
+
+		// Abort if no class was available to process the character or if
+		// processing failed.
+		if (!outputOk)
+			{
+			aParam.iPosInText = textIter.LengthToStart();
+			return outputOk;
+			}
+
+		// Did the glyph selector that processed the character want the 
+		// pen to advance?
+		if (gss.iPen == TGlyphSelectionState::EPenAdvance_Yes)
+			{
+			aParam.iPen.iX += gss.iAdvance.iWidth;
+			aParam.iPen.iY += gss.iAdvance.iHeight;
+			gss.iPen = TGlyphSelectionState::EPenAdvance_No;
+			}
+
+		// Here we assume the Process() methods have advanced the iterator as
+		// they consume characters they handle so that it now points to the
+		// character to process next time around the loop.
+		}
+	while (!textIter.AtEnd()	// We still have more text to process
+		&& (gss.iClusterState == TGlyphSelectionState::EGClusterNotComplete) // Glyph cluster !complete
+		&& (aParam.iOutputGlyphs < TPositionParam::EMaxOutputGlyphs)); // Room for another glyph entry
+
+	// If a complete glyph cluster has been identified then we should try to
+	// compose it as fully as possible. Obviously, if it only contains one
+	// character then it is already fully composed so we can ignore it.
+	// Skip this if any language-specific processing has taken place.
+	if (gss.iGlyphPostCombine == TGlyphSelectionState::EGPostCombine_Yes
+		&& gss.iClusterState == TGlyphSelectionState::EGClusterComplete)
+		{
+		// Leave room to handle surrogates - Decompose() outputs UTF-16
+		// The max that can come out of the previous stage is TPositionParam::EMaxOutputGlyphs
+		// long with only one base char at the start. Even if that base char decomposed to the
+		// max it could only be MaxOutputGlyphs long, giving a total of (2 * MaxOutputGlyphs)-1
+		// Conceivably the use of surrogates throughout could double that when converting to UTF-16
+		TBuf<TPositionParam::EMaxOutputGlyphs * 4> decomposeArray;
+		TBool success = ETrue;
+		// Go through the glyph cluster one char at a time
+		for (TInt i = 0; i < aParam.iOutputGlyphs; i++)
+			{
+			TChar singleChar(aParam.iOutput[i].iCode);
+			// If first character try to decompose it otherwise just take the character
+			TBool decomposed = EFalse;
+			TPtrC16 decomposition;
+			if (i == 0)
+				decomposed = singleChar.Decompose(decomposition);
+			if (decomposed)
+				{ // Pick up the sequence of characters
+				decomposeArray.Append(decomposition);
+				}
+			else
+				{ // Keep the original character
+				if (singleChar > 0xFFFF)
+					{ // Above the BMP so we need a surrogate pair for UTF-16
+					// This calculation really ought to go into a separate routine - probably part of TChar
+					decomposeArray.Append(HighSurrogate(singleChar));
+					decomposeArray.Append(LowSurrogate(singleChar));
+					}
+				else
+					{ // It's not a surrogate so we just need to cast it down (since it's safe)
+					decomposeArray.Append(singleChar);
+					}
+				}
+			// Guard against bad input overflowing the array and causing a panic
+			if (decomposeArray.Length() > (TPositionParam::EMaxOutputGlyphs * 4) - 2)
+				{ // too long to be a viable composition so don't try
+				success = EFalse;
+				break;
+				}
+			}
+		TUint composedChar = 0;
+		TOpenFontCharMetrics metrics;
+		TPositionParam::TOutput output;
+		TSize advance; // gets initialized to 0,0
+		if (success)
+			{
+			//Now try and compose the string to a single character
+			success = TChar::Compose(composedChar, decomposeArray);
+			}
+		if (success)
+			{
+			// if single char is not in font or can't get char metrics for it
+			// N.B. This will probably always return metrics because if the
+			// char is not in the font this will usually return the substitute
+			// "missing" glyph (and its metrics). There should be a function to
+			// really tell you if a glyph is in the font - but there isn't.
+			if (GetCharacterData(composedChar, metrics, output.iBitmap, output.iBitmapSize) == CFont::ENoCharacterData)
+				success = EFalse;
+			}
+		if (success)
+			{
+			// We should replace the glyph cluster made from multiple chars
+			// with the correct single char and fix up the rest of the output
+			// parameters as well
+			output.iCode = composedChar;
+			// Set the glyph's bounds and record pen advancement.
+			if (aParam.iDirection == CFont::EVertical)
+				{
+				metrics.GetVertBounds(output.iBounds);
+				advance.iHeight = metrics.VertAdvance();
+				}
+			else
+				{
+				metrics.GetHorizBounds(output.iBounds);
+				advance.iWidth = metrics.HorizAdvance();
+				}
+			// Adjust the glyph's bounding box to offset it from the pen
+			// position (origin of drawing). For speed increment directly.
+			output.iBounds.iTl.iX += penCopy.iX;
+			output.iBounds.iBr.iX += penCopy.iX;
+			output.iBounds.iTl.iY += penCopy.iY;
+			output.iBounds.iBr.iY += penCopy.iY;
+			// Set penCopy, the copy of aParam.iPen that we made
+			penCopy.iX += advance.iWidth;
+			penCopy.iY += advance.iHeight;
+			// Overwrite the original output parameters for the glyph cluster
+			// with the values for the single composed character
+			aParam.iOutput[0] = output;
+			aParam.iOutputGlyphs = 1;
+			aParam.iPen = penCopy;	
+			}
+		}
+
+	// Exit routine with result and increment position in text to 
+	// where we reached during processing to avoid any caller loops from 
+	// infinite execution.
+	aParam.iPosInText = textIter.LengthToStart();
+	return outputOk;
+	}
+
+/** Gets the character metrics for a character.
+	
+@param aCode The character code.
+@param aMetrics On return, contains the character bitmap.
+@param aBitmap On return, this points to NULL.
+@param aBitmapSize On return, this has a size of (0,0).
+@return ECharacterWidthOnly 
+*/
+EXPORT_C CFont::TCharacterDataAvailability CFont::DoGetCharacterData(TUint aCode,TOpenFontCharMetrics& aMetrics,
+		const TUint8*& aBinaryData,TSize& aBitmapSize) const
+	{
+	int width = CharWidthInPixels(aCode);
+	aMetrics.SetHorizAdvance(width);
+	aBinaryData = NULL;
+	// For speed set to 0 directly rather than call SetSize()
+	aBitmapSize.iWidth = 0;
+	aBitmapSize.iHeight = 0;
+
+	/*
+	Set the other metrics using the width and font metrics.
+	This allows derived classes that don't override this function, like CInfoFont,
+	to give usable results for TextWidthInPixels and MeasureText.
+	*/
+	aMetrics.SetWidth(width);
+	int height = HeightInPixels();
+	aMetrics.SetHeight(height);
+	aMetrics.SetVertAdvance(height);
+	aMetrics.SetHorizBearingX(0);
+	aMetrics.SetHorizBearingY(AscentInPixels());
+	aMetrics.SetVertBearingX(0);
+	aMetrics.SetVertBearingY(0);
+
+	return CFont::ECharacterWidthOnly;
+	}
+
+
+/** Determines if aLeftCharacter and aRightCharacter affect each other's
+contextual glyph form if placed next to each other. If either character
+is a combining character, EFalse will be returned, which is not generally
+useful information. Pass in base characters ignoring intervening combining
+characters.
+@param aLeftCharacter Unicode code for the character that stands on the left.
+@param aRightCharacter Unicode code for the character that stands on the right.
+@return EFalse if the characters do not affect the contextual glyphs that are
+be chosen when the two are rendered together, compared to being separated 
+(for example by a space). */	
+EXPORT_C TBool CFont::CharactersJoin(TInt aLeftCharacter, TInt aRightCharacter)
+	{
+	return GlyphSelector_Arabic::CharactersJoin(aLeftCharacter, aRightCharacter);
+	}
+
+/** API extension system that enables the caller to access a particular API
+extension function. N.B. Any overload of this function in a derived class
+should call its immediate parent implementation for any extension function Uid
+that it does not recognize and handle.
+@param aInterfaceId UID of the required extension function
+@param aParam Pointer to an arbitrary parameter block that can be used to
+provide and/or return information to/from the particular extension function,
+defaults to NULL.
+@return Integer return value from extension function
+@internalTechnology
+@released
+*/
+EXPORT_C TInt CFont::DoExtendedFunction(TUid aFunctionId, TAny* /* aParam */) const
+	{
+	if (KFontCapitalAscent	== aFunctionId ||
+		KFontMaxAscent		== aFunctionId)
+		{
+		return AscentInPixels();
+		}
+	else if (KFontStandardDescent	== aFunctionId ||
+			 KFontMaxDescent		== aFunctionId)
+		{
+		return DescentInPixels();
+		}
+	else if (KFontLineGap == aFunctionId)
+		{ // 1.2 of em height (rounded) is reasonable approximation of interline gap
+		return (HeightInPixels() * 12 + 5) / 10;
+		}
+	return KErrNotFound;
+	}
+
+EXPORT_C TUid CFont::TypeUid() const
+	{
+	return DoTypeUid();
+	}
+
+EXPORT_C TInt CFont::HeightInPixels() const
+	{
+	return DoHeightInPixels();
+	}
+
+EXPORT_C TInt CFont::AscentInPixels() const
+	{
+	return DoAscentInPixels();
+	}
+
+EXPORT_C TInt CFont::DescentInPixels() const
+	{
+	return DoDescentInPixels();
+	}
+
+EXPORT_C TInt CFont::CharWidthInPixels(TChar aChar) const
+	{
+	return DoCharWidthInPixels(aChar);
+	}
+
+EXPORT_C TInt CFont::TextWidthInPixels(const TDesC& aText) const
+	{
+	return DoTextWidthInPixels(aText);
+	}
+
+EXPORT_C TInt CFont::BaselineOffsetInPixels() const
+	{
+	return DoBaselineOffsetInPixels();
+	}
+
+EXPORT_C TInt CFont::TextCount(const TDesC& aText,TInt aWidthInPixels) const
+	{
+	return DoTextCount(aText, aWidthInPixels);
+	}
+
+EXPORT_C TInt CFont::TextCount(const TDesC& aText, TInt aWidthInPixels, TInt& aExcessWidthInPixels) const
+	{
+	return DoTextCount(aText, aWidthInPixels, aExcessWidthInPixels);
+	}
+
+EXPORT_C TInt CFont::MaxCharWidthInPixels() const
+	{
+	return DoMaxCharWidthInPixels();
+	}
+
+EXPORT_C TInt CFont::MaxNormalCharWidthInPixels() const
+	{
+	return DoMaxNormalCharWidthInPixels();
+	}
+
+EXPORT_C TFontSpec CFont::FontSpecInTwips() const
+	{
+	return DoFontSpecInTwips();
+	}
+	
+/** Gets the character metrics for a character.
+	
+@param aCode The character code.
+@param aMetrics On return, contains the character bitmap.
+@param aBitmap On return, this points to NULL.
+@param aBitmapSize On return, this has a size of (0,0).
+@return ECharacterWidthOnly 
+*/
+EXPORT_C CFont::TCharacterDataAvailability CFont::GetCharacterData(TUint aCode, TOpenFontCharMetrics& aMetrics, const TUint8*& aBitmap, TSize& aBitmapSize) const
+	{
+	return DoGetCharacterData(aCode, aMetrics, aBitmap, aBitmapSize);
+	}
+
+/** Transforms one cluster of characters (base character plus combining marks,
+ligature or indic syllable) into one cluster of glyphs together with their
+positions. Repeated calls of this function (for the same input text) are
+considerably slower than repeated calls of GetCharacterPosition2 for Indic text
+(such as Hindi), as GetCharacterPosition2 can cache information between calls.
+@param aParam Input and output parameters
+@return True for success
+@see GetCharacterPosition2
+@publishedAll */
+EXPORT_C TBool CFont::GetCharacterPosition(TPositionParam& aParam) const
+	{
+	return DoGetCharacterPosition(aParam);
+	}
+
+/** Enables the caller to access a particular API
+extension function. N.B. Any overload of this function in a derived class
+should call its immediate parent implementation for any extension function UID
+that it does not recognize and handle.
+@param aFunctionId UID of the required extension function
+@param aParam Pointer to an arbitrary parameter block that can be used to
+provide and/or return information to/from the particular extension function,
+defaults to NULL.
+@return Integer return value from extension function 
+*/
+EXPORT_C TInt CFont::ExtendedFunction(TUid aFunctionId, TAny* aParam) const
+	{
+	return DoExtendedFunction(aFunctionId, aParam);
+	}
+	
+EXPORT_C TInt CFont::TextWidthInPixels(const TDesC& aText,const TMeasureTextInput* aParam) const
+	{
+	TTextWidthInternal context;
+	TTextWidthInternal* contextPtr = &context;
+	contextPtr->iText.Set(aText);
+	contextPtr->iParam.iStartInputChar = aParam->iStartInputChar;
+	contextPtr->iParam.iEndInputChar = aParam->iEndInputChar;
+	return DoExtendedFunction(KTextInContextWidthInPixelsUid, (TAny*)contextPtr);
+	}
+
+/**
+Maps TLanguage to TScript.
+
+EScriptOther represents languages not yet supported in KTScript2GlyphSample.
+This array does not handle ELangNone and ELangMaximum to save storage space.
+*/
+const TInt GlyphSample::KTLanguage2TScript[] = 
+	{
+	EScriptNone,			// 00 ELangTest
+	EScriptLatin,			// 01 ELangEnglish
+	EScriptLatin,			// 02 ELangFrench
+	EScriptLatin,			// 03 ELangGerman
+	EScriptLatin,			// 04 ELangSpanish
+	EScriptLatin,			// 05 ELangItalian
+	EScriptLatin,			// 06 ELangSwedish
+	EScriptLatin,			// 07 ELangDanish
+	EScriptLatin,			// 08 ELangNorwegian
+	EScriptLatin,			// 09 ELangFinnish
+	EScriptLatin,			// 10 ELangAmerican
+	EScriptLatin,			// 11 ELangSwissFrench
+	EScriptLatin,			// 12 ELangSwissGerman
+	EScriptLatin,			// 13 ELangPortuguese
+	EScriptLatin,			// 14 ELangTurkish
+	EScriptLatin,			// 15 ELangIcelandic
+	EScriptCyrillic,		// 16 ELangRussian
+	EScriptLatin,			// 17 ELangHungarian
+	EScriptLatin,			// 18 ELangDutch
+	EScriptLatin,			// 19 ELangBelgianFlemish
+	EScriptLatin,			// 20 ELangAustralian
+	EScriptLatin,			// 21 ELangBelgianFrench
+	EScriptLatin,			// 22 ELangAustrian
+	EScriptLatin,			// 23 ELangNewZealand
+	EScriptLatin,			// 24 ELangInternationalFrench
+	EScriptLatin,			// 25 ELangCzech
+	EScriptLatin,			// 26 ELangSlovak
+	EScriptLatin,			// 27 ELangPolish
+	EScriptLatin,			// 28 ELangSlovenian
+	EScriptHanIdeographs,	// 29 ELangTaiwanChinese
+	EScriptHanIdeographs,	// 30 ELangHongKongChinese
+	EScriptHanIdeographs,	// 31 ELangPrcChinese
+	EScriptHanIdeographs,	// 32 ELangJapanese
+	EScriptThai,			// 33 ELangThai
+	EScriptLatin,			// 34 ELangAfrikaans
+	EScriptLatin,			// 35 ELangAlbanian
+	EScriptOther,			// 36 ELangAmharic
+	EScriptArabic,			// 37 ELangArabic
+	EScriptOther,			// 38 ELangArmenian
+	EScriptOther,			// 39 ELangTagalog
+	EScriptCyrillic,		// 40 ELangBelarussian
+	EScriptOther,			// 41 ELangBengali
+	EScriptCyrillic,		// 42 ELangBulgarian
+	EScriptOther,			// 43 ELangBurmese
+	EScriptLatin,			// 44 ELangCatalan
+	EScriptLatin,			// 45 ELangCroatian
+	EScriptLatin,			// 46 ELangCanadianEnglish
+	EScriptLatin,			// 47 ELangInternationalEnglish
+	EScriptLatin,			// 48 ELangSouthAfricanEnglish
+	EScriptLatin,			// 49 ELangEstonian
+	EScriptArabic,			// 50 ELangFarsi
+	EScriptLatin,			// 51 ELangCanadianFrench
+	EScriptLatin,			// 52 ELangScotsGaelic
+	EScriptOther,			// 53 ELangGeorgian
+	EScriptGreek,			// 54 ELangGreek
+	EScriptGreek,			// 55 ELangCyprusGreek
+	EScriptOther,			// 56 ELangGujarati
+	EScriptHebrew,			// 57 ELangHebrew
+	EScriptDevanagari,		// 58 ELangHindi
+	EScriptLatin,			// 59 ELangIndonesian
+	EScriptLatin,			// 60 ELangIrish
+	EScriptLatin,			// 61 ELangSwissItalian
+	EScriptOther,			// 62 ELangKannada
+	EScriptCyrillic,		// 63 ELangKazakh
+	EScriptOther,			// 64 ELangKhmer
+	EScriptHanIdeographs,	// 65 ELangKorean
+	EScriptOther,			// 66 ELangLao
+	EScriptLatin,			// 67 ELangLatvian
+	EScriptLatin,			// 68 ELangLithuanian
+	EScriptCyrillic,		// 69 ELangMacedonian
+	EScriptLatin,			// 70 ELangMalay
+	EScriptOther,			// 71 ELangMalayalam
+	EScriptDevanagari,		// 72 ELangMarathi
+	EScriptLatin,			// 73 ELangMoldavian
+	EScriptOther,			// 74 ELangMongolian
+	EScriptLatin,			// 75 ELangNorwegianNynorsk
+	EScriptLatin,			// 76 ELangBrazilianPortuguese
+	EScriptOther,			// 77 ELangPunjabi
+	EScriptLatin,			// 78 ELangRomanian
+	EScriptCyrillic,		// 79 ELangSerbian
+	EScriptOther,			// 80 ELangSinhalese
+	EScriptLatin,			// 81 ELangSomali
+	EScriptLatin,			// 82 ELangInternationalSpanish
+	EScriptLatin,			// 83 ELangLatinAmericanSpanish
+	EScriptLatin,			// 84 ELangSwahili
+	EScriptLatin,			// 85 ELangFinlandSwedish
+	EScriptNone,			// 86 ELangReserved1
+	EScriptOther,			// 87 ELangTamil
+	EScriptOther,			// 88 ELangTelugu
+	EScriptOther,			// 89 ELangTibetan
+	EScriptOther,			// 90 ELangTigrinya
+	EScriptLatin,			// 91 ELangCyprusTurkish
+	EScriptCyrillic,		// 92 ELangTurkmen
+	EScriptCyrillic,		// 93 ELangUkrainian
+	EScriptArabic,			// 94 ELangUrdu
+	EScriptNone,			// 95 ELangReserved2
+	EScriptLatin,			// 96 ELangVietnamese
+	EScriptLatin,			// 97 ELangWelsh
+	EScriptLatin,			// 98 ELangZulu
+	};
+
+/**
+Maps TScript to glyph samples.
+
+The order of samples definition has to follow the script order in TScript.
+
+Supported scripts	Fonts used to experiment/determine glyph samples
+
+Latin				Arial, Times, Century
+Greek				Ditto
+Cyrillic			Ditto
+Hebrew				Aharoni, David, FrankRuehl, Levenim MT, Miriam, Narkisim, Rod
+Arabic				Andalus, Arabic Transparent, Simplified Arabic, Traditional Arabic
+Devanagari			Mangal
+Thai				Angsana New, Browallia, Cordia New, DilleniaUPC, EucrosiaUPC,
+					FreesiaUPC, IrisUPC, JasmineUPC, KodchiangUPC, LilyUPC
+HanIdeographs		Chinese	: SimSun, SimHei (Simplified) / MingLiU (Traditional)
+					Japanese: MS Mincho, MS Gothic
+					Korean	: Batang, Gulim
+*/
+const TText* const GlyphSample::KTScript2GlyphSample[] = 
+	{
+	//
+	// 02 EScriptLatin
+	//
+	//	0x00C0 - Ascent : Capital letter A with grave (Latin-1 Supplement)
+	//	0x013A - Ascent : Small letter l with acute (Latin Extended A)
+	//	0x1EA2 - Ascent : Capital letter A with hook above (Latin Extended Additional)
+	//	0x00C7 - Descent: Capital letter C with cedilla (Latin-1 Supplement)
+	//	0x0163 - Descent: Small letter t with cedilla (Latin Extended A)
+	//
+	_S("\x00C0\x013A\x1EA2\x00C7\x0163"),
+	//
+	// 03 EScriptGreek
+	//
+	//	0x03AA - Ascent : Capital letter iota with dialytika
+	//	0x03AB - Ascent : Capital letter upsilon with dialytika
+	//	0x03AE - Descent: Small letter eta with tonos
+	//	0x03B2 - Descent: Small letter beta
+	//	0x03C8 - Descent: Small letter psi
+	//
+	_S("\x03AA\x03AB\x03AE\x03B2\x03C8"),
+	//
+	// 04 EScriptCyrillic
+	//
+	//	0x0403 - Ascent : Capital letter gje
+	//	0x0419 - Ascent : Capital letter short i
+	//	0x0440 - Descent: Small letter er
+	//	0x0452 - Descent: Small letter dje
+	//	0x0458 - Descent: Small letter je
+	//
+	_S("\x0403\x0419\x0440\x0452\x0458"),
+	//
+	// 05 EScriptHebrew
+	//
+	//	0x05BE - Ascent : Punctuation maqaf
+	//	0x05DC - Ascent : Letter lamed
+	//	0x05B0 - Descent: Point sheva
+	//	0x05BD - Descent: Point meteg
+	//	0x05E7 - Descent: Letter qof
+	//
+	_S("\x05BE\x05DC\x05B0\x05BD\x05E7"),
+	//
+	// 06 EScriptArabic
+	//
+	// 	0x0670 - Ascent : Alef above (Arabic)
+	// 	0x0671 - Ascent : Hamzat Wasl on Alef  isolated form
+	// 	0x064D - Descent: Kasratan (Arabic)
+	// 	0xFB7B - Descent: Final form of 0686
+	// 	0xFBF2 - Descent: Final form of 064A
+	//
+	//PDEF120737: EScriptArabic value has been changed for this defect & tested using the font file provided by client (i.e. kamelion arabic font).
+	//The client's font file can't be used for IPR reasons. Thus the test code to demonstrate this defect
+	//is not added. Also, there was no other font file available that reproduces this defect. 
+	//
+	_S("\x0670\x0671\x064D\xFB7B\xFBF2"),
+	//
+	// 07 EScriptDevanagari
+	//
+	//	0x0914 - Ascent : Letter au
+	//	0x0951 - Ascent : Stress sign udatta
+	//	0x0941 - Descent: Vowel sign u
+	//	0x0944 - Descent: Vowel sign rr
+	//	0x0963 - Descent: Vowel sign vocalic ll
+	//
+	_S("\x0914\x0951\x0941\x0944\x0963"),
+	//
+	// 08 EScriptThai
+	//
+	//	0x0E49 - Ascent : Character mai tho
+	//	0x0E4B - Ascent : Character mai chattawa
+	//	0x0E0E - Descent: Character do chada
+	//	0x0E24 - Descent: Character ru
+	//	0x0E39 - Descent: Character sara uu
+	//
+	_S("\x0E49\x0E4B\x0E0E\x0E24\x0E39"),
+	//
+	// 09 EScriptHanIdeographs
+	//
+	//	0x1100 - Ascent/Descent: Korean
+	//	0x4E1C - Ascent/Descent: Chinese Simplified
+	//	0x5283 - Ascent/Descent: Japanese
+	//	0x758A - Ascent : Chinese Traditional
+	//	0x7BEA - Descent: Chinese Traditional
+	//
+	_S("\x1100\x4E1C\x5283\x758A\x7BEA"),
+	};
+
+/**
+Maps a TLanguage type to the TScript type.
+@internalTechnology
+@param aLanguage The language.
+@return A TInt representing the script, or 
+EScriptNone if its not defined for aLanguage.
+*/
+EXPORT_C TInt GlyphSample::TLanguage2TScript(TLanguage aLanguage)
+	{
+	if (ELangNone == aLanguage || ELangMaximum == aLanguage || aLanguage >= (sizeof(KTLanguage2TScript)/sizeof(KTLanguage2TScript[0])))
+		{
+		return EScriptNone;
+		}
+	return KTLanguage2TScript[aLanguage];
+	}
+
+/**
+Maps a TScript type to some glyph samples which are stored as Unicode.
+@internalTechnology
+@param aScript The script.
+@return A TPtrC pointing to the first glyph sample,
+or empty if no samples is defined for aScript.
+*/
+EXPORT_C const TPtrC GlyphSample::TScript2GlyphSample(TInt aScript)
+	{
+	if (EScriptOther >= aScript)
+		{
+		return TPtrC();
+		}
+	// -3 to offset EScriptDefault, EScriptNone and EScriptOther
+	// being the first three elements in TScript.
+	return TPtrC(KTScript2GlyphSample[aScript - 3]);
+	}