graphicsdeviceinterface/gdi/lookuptable/lookuptable.h
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// Copyright (c) 2006-2009 Nokia Corporation and/or its subsidiary(-ies).
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// All rights reserved.
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// This component and the accompanying materials are made available
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// under the terms of "Eclipse Public License v1.0"
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// which accompanies this distribution, and is available
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// at the URL "http://www.eclipse.org/legal/epl-v10.html".
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//
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// Initial Contributors:
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// Nokia Corporation - initial contribution.
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//
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// Contributors:
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//
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// Description:
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//
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#ifndef __LOOKUPTABLE_H__
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#define __LOOKUPTABLE_H__
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#include <e32std.h>
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/**
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@internalTechnology
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*/
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 IMPORT_C const TUint16* Convert16to32bppLow();
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 IMPORT_C const TUint32* Convert16to32bppHigh();
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/**
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Returns the pointer to the table of 16-bit normalisation table.
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The table is currently used for performing un-multiplying Premultiplied Alpha color channels.
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Use: Let x be c * a/255, and y = c, then y = (x/a)*255, where a is in 0-255 range.
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		To use this table, use y = (x * Table[a])>>8. i.e, the inaccurate division is converted 
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		to more accurate multiplication and shift.
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@return pointer to the normalisation table.
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@internalTechnology
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*/
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IMPORT_C const TUint16* PtrTo16BitNormalisationTable();
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#endif