1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/os/graphics/graphicsdeviceinterface/gdi/inc/blendingalgorithms.inl	Fri Jun 15 03:10:57 2012 +0200
     1.3 @@ -0,0 +1,133 @@
     1.4 +// Copyright (c) 2007-2009 Nokia Corporation and/or its subsidiary(-ies).
     1.5 +// All rights reserved.
     1.6 +// This component and the accompanying materials are made available
     1.7 +// under the terms of "Eclipse Public License v1.0"
     1.8 +// which accompanies this distribution, and is available
     1.9 +// at the URL "http://www.eclipse.org/legal/epl-v10.html".
    1.10 +//
    1.11 +// Initial Contributors:
    1.12 +// Nokia Corporation - initial contribution.
    1.13 +//
    1.14 +// Contributors:
    1.15 +//
    1.16 +// Description:
    1.17 +//
    1.18 +
    1.19 +const TUint32 KRBMask = 0x00ff00ff;
    1.20 +const TUint32 KAGMask = 0xff00ff00;
    1.21 +const TUint32 KGMask  = 0x0000ff00;
    1.22 +
    1.23 +//Algoriths for Premultiplied alpha screenmode/pixel format.
    1.24 +
    1.25 +inline TUint32 PMAPixelBlend(TUint32 aDestPixel, TUint32 aSrcPixel, TUint8 aMask)
    1.26 +	{
    1.27 +	if(aMask)
    1.28 +		{
    1.29 +		if(aMask == 0xff) // opaque, so unchanged
    1.30 +			{
    1.31 +			return aSrcPixel;
    1.32 +			}
    1.33 +		else
    1.34 +			{
    1.35 +			return PMABlend_noChecks(aDestPixel, aSrcPixel, aMask);
    1.36 +			}
    1.37 +		}
    1.38 +	 else // completely transparent
    1.39 +		{
    1.40 +		return aDestPixel;
    1.41 + 		}
    1.42 +	}
    1.43 +
    1.44 +inline TUint32 PMAPixelBlend(TUint32 aDestPixel, TUint32 aSrcPixel)
    1.45 +	{
    1.46 +	TUint8 mask = (TUint8)(aSrcPixel >> 24);
    1.47 +	return PMAPixelBlend(aDestPixel, aSrcPixel, mask);
    1.48 +	}
    1.49 +
    1.50 +inline TUint32 PMABlend_noChecks(TUint32 aDestPixel, TUint32 aSrcPixel, TUint8 aMaskingFactor)
    1.51 +	{
    1.52 +	TUint32 src_c = aSrcPixel & KRBMask;
    1.53 +	TUint32 dst_c = aDestPixel  & KRBMask;
    1.54 +	const TUint32 mask = 0x0100 - aMaskingFactor;
    1.55 +	dst_c = (src_c +  ((mask * dst_c)>>8)) & KRBMask;
    1.56 +	src_c = (aSrcPixel & KAGMask)>>8;
    1.57 +	TUint32 dst_ag = (aDestPixel & KAGMask)>>8;
    1.58 +	dst_c |= ((src_c +  ((mask * dst_ag)>>8)) & KRBMask)<<8;
    1.59 +	return dst_c;
    1.60 +	}
    1.61 +
    1.62 +inline void PMABlend_noChecksInplace(TUint32& aDest_io, const TUint32& aSrcPixel, TUint8 aMaskingFactor)
    1.63 +	{
    1.64 +	TUint32 src_c = aSrcPixel & KRBMask;
    1.65 +	TUint32 dst_ag = (aDest_io & KAGMask) >> 8;
    1.66 +	aDest_io = aDest_io  & KRBMask;
    1.67 +	const TUint32 mask = 0x0100 - aMaskingFactor;
    1.68 +	aDest_io = (src_c +  ((mask * aDest_io) >> 8)) & KRBMask;
    1.69 +	src_c = (aSrcPixel & KAGMask) >> 8;
    1.70 +	aDest_io |= ((src_c +  ((mask * dst_ag) >> 8)) & KRBMask)<<8;
    1.71 +	}
    1.72 +
    1.73 +inline void PMAInplaceBlend(TUint32& aDest_io, TUint32& aSrc_in)
    1.74 +	{
    1.75 +	TUint8 mask = (TUint8)(aSrc_in >> 24);
    1.76 +	if(mask)
    1.77 +		{
    1.78 +		if(mask == 0xff) // opaque, so dst = src.
    1.79 +			{
    1.80 +			aDest_io = aSrc_in;
    1.81 +			}
    1.82 +		else
    1.83 +			{
    1.84 +			PMABlend_noChecksInplace(aDest_io, aSrc_in, mask);
    1.85 +			}
    1.86 +		}
    1.87 +	//else src completely transparent, so dst unchanged.
    1.88 +	}
    1.89 +
    1.90 +inline TUint32 NonPMA2PMAPixel(TUint32 aPixel)
    1.91 +	{
    1.92 +	TUint8 tA = (TUint8)(aPixel >> 24);
    1.93 +	if (tA==0)
    1.94 +		{ 
    1.95 +		return 0;
    1.96 +		}
    1.97 +	if (tA==0xff) 
    1.98 +		{
    1.99 +		return aPixel;
   1.100 +		}
   1.101 +
   1.102 +	// Use a bias value of 128 rather than 255, but also add 1/256 of the numerator 
   1.103 +	// before dividing the sum by 256.
   1.104 +
   1.105 +	TUint32 tap1=tA+1;
   1.106 +	TUint32 scaledRB = (aPixel & KRBMask) * tap1;
   1.107 +	TUint32 scaledG = (aPixel & KGMask ) * tap1;
   1.108 +	return (aPixel & 0xff000000) | ((scaledRB>>8) & KRBMask) | ((scaledG>>8)& KGMask);
   1.109 +	}
   1.110 +
   1.111 +inline TUint32 PMA2NonPMAPixel(TUint32 aPixel, const TUint16* aNormTable)
   1.112 +	{
   1.113 +	TUint8 alpha = (TUint8)(aPixel >> 24);
   1.114 +	if (alpha==0)
   1.115 +		{ 
   1.116 +		return 0;
   1.117 +		}
   1.118 +	if (alpha==0xff) 
   1.119 +		{
   1.120 +		return aPixel;
   1.121 +		}
   1.122 +	TUint16 norm = aNormTable[alpha];
   1.123 +	TUint32 norm_rb = (((aPixel & KRBMask) * norm) >> 8) & KRBMask;
   1.124 +	TUint32 norm_g =  (((aPixel & KGMask ) * norm) >> 8) & KGMask;
   1.125 +	return ((aPixel & 0xff000000) | norm_rb | norm_g);
   1.126 +	}
   1.127 +
   1.128 +inline void Convert2PMA(TUint32& aInOutValue)
   1.129 +	{
   1.130 +	aInOutValue = NonPMA2PMAPixel(aInOutValue);
   1.131 +	}
   1.132 +
   1.133 +inline void Convert2NonPMA(TUint32& aInOutValue, const TUint16* aNormTable)
   1.134 +	{
   1.135 +	aInOutValue = PMA2NonPMAPixel(aInOutValue, aNormTable);
   1.136 +	}
   1.137 \ No newline at end of file