--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graphicsdeviceinterface/gdi/inc/blendingalgorithms.inl	Tue Feb 02 01:47:50 2010 +0200
@@ -0,0 +1,133 @@
+// 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:
+//
+
+const TUint32 KRBMask = 0x00ff00ff;
+const TUint32 KAGMask = 0xff00ff00;
+const TUint32 KGMask  = 0x0000ff00;
+
+//Algoriths for Premultiplied alpha screenmode/pixel format.
+
+inline TUint32 PMAPixelBlend(TUint32 aDestPixel, TUint32 aSrcPixel, TUint8 aMask)
+	{
+	if(aMask)
+		{
+		if(aMask == 0xff) // opaque, so unchanged
+			{
+			return aSrcPixel;
+			}
+		else
+			{
+			return PMABlend_noChecks(aDestPixel, aSrcPixel, aMask);
+			}
+		}
+	 else // completely transparent
+		{
+		return aDestPixel;
+ 		}
+	}
+
+inline TUint32 PMAPixelBlend(TUint32 aDestPixel, TUint32 aSrcPixel)
+	{
+	TUint8 mask = (TUint8)(aSrcPixel >> 24);
+	return PMAPixelBlend(aDestPixel, aSrcPixel, mask);
+	}
+
+inline TUint32 PMABlend_noChecks(TUint32 aDestPixel, TUint32 aSrcPixel, TUint8 aMaskingFactor)
+	{
+	TUint32 src_c = aSrcPixel & KRBMask;
+	TUint32 dst_c = aDestPixel  & KRBMask;
+	const TUint32 mask = 0x0100 - aMaskingFactor;
+	dst_c = (src_c +  ((mask * dst_c)>>8)) & KRBMask;
+	src_c = (aSrcPixel & KAGMask)>>8;
+	TUint32 dst_ag = (aDestPixel & KAGMask)>>8;
+	dst_c |= ((src_c +  ((mask * dst_ag)>>8)) & KRBMask)<<8;
+	return dst_c;
+	}
+
+inline void PMABlend_noChecksInplace(TUint32& aDest_io, const TUint32& aSrcPixel, TUint8 aMaskingFactor)
+	{
+	TUint32 src_c = aSrcPixel & KRBMask;
+	TUint32 dst_ag = (aDest_io & KAGMask) >> 8;
+	aDest_io = aDest_io  & KRBMask;
+	const TUint32 mask = 0x0100 - aMaskingFactor;
+	aDest_io = (src_c +  ((mask * aDest_io) >> 8)) & KRBMask;
+	src_c = (aSrcPixel & KAGMask) >> 8;
+	aDest_io |= ((src_c +  ((mask * dst_ag) >> 8)) & KRBMask)<<8;
+	}
+
+inline void PMAInplaceBlend(TUint32& aDest_io, TUint32& aSrc_in)
+	{
+	TUint8 mask = (TUint8)(aSrc_in >> 24);
+	if(mask)
+		{
+		if(mask == 0xff) // opaque, so dst = src.
+			{
+			aDest_io = aSrc_in;
+			}
+		else
+			{
+			PMABlend_noChecksInplace(aDest_io, aSrc_in, mask);
+			}
+		}
+	//else src completely transparent, so dst unchanged.
+	}
+
+inline TUint32 NonPMA2PMAPixel(TUint32 aPixel)
+	{
+	TUint8 tA = (TUint8)(aPixel >> 24);
+	if (tA==0)
+		{ 
+		return 0;
+		}
+	if (tA==0xff) 
+		{
+		return aPixel;
+		}
+
+	// Use a bias value of 128 rather than 255, but also add 1/256 of the numerator 
+	// before dividing the sum by 256.
+
+	TUint32 tap1=tA+1;
+	TUint32 scaledRB = (aPixel & KRBMask) * tap1;
+	TUint32 scaledG = (aPixel & KGMask ) * tap1;
+	return (aPixel & 0xff000000) | ((scaledRB>>8) & KRBMask) | ((scaledG>>8)& KGMask);
+	}
+
+inline TUint32 PMA2NonPMAPixel(TUint32 aPixel, const TUint16* aNormTable)
+	{
+	TUint8 alpha = (TUint8)(aPixel >> 24);
+	if (alpha==0)
+		{ 
+		return 0;
+		}
+	if (alpha==0xff) 
+		{
+		return aPixel;
+		}
+	TUint16 norm = aNormTable[alpha];
+	TUint32 norm_rb = (((aPixel & KRBMask) * norm) >> 8) & KRBMask;
+	TUint32 norm_g =  (((aPixel & KGMask ) * norm) >> 8) & KGMask;
+	return ((aPixel & 0xff000000) | norm_rb | norm_g);
+	}
+
+inline void Convert2PMA(TUint32& aInOutValue)
+	{
+	aInOutValue = NonPMA2PMAPixel(aInOutValue);
+	}
+
+inline void Convert2NonPMA(TUint32& aInOutValue, const TUint16* aNormTable)
+	{
+	aInOutValue = PMA2NonPMAPixel(aInOutValue, aNormTable);
+	}
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