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// Copyright (c) 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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#include "wavegenerator.h"
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#include <e32math.h>
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/**
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Generates a set of values that resembles a sine wave that has no negative
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values.
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*/
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void WaveGenerator::GenerateSineWave(TValueList& aResults, TInt aNumSamples,
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TReal aAmplitude, TReal aFrequency, TBool aPositiveValues)
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{
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TReal prefix = -1;
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TReal part = 1.0 / aNumSamples;
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TReal time = 0;
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TReal preCalculation = 3.14159265358979323846 * aFrequency;
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if (aPositiveValues)
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{
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prefix = 1;
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}
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TReal sinResult;
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for (TInt i = aNumSamples; i > 0; --i)
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{
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time += part;
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Math::Sin(sinResult, preCalculation * time);
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aResults.Append(prefix * Abs(aAmplitude * sinResult));
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}
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}
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