diff -r 000000000000 -r bde4ae8d615e os/graphics/graphicsdeviceinterface/gdi/inc/blendingalgorithms.inl --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/os/graphics/graphicsdeviceinterface/gdi/inc/blendingalgorithms.inl Fri Jun 15 03:10:57 2012 +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); + } \ No newline at end of file