/*

* Copyright (c) 2008 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:   

*

*/

#include "HuiFxVg10ColorizeFilter.h"

#include "HuiFxConstants.h"

CHuiFxVg10ColorizeFilter* CHuiFxVg10ColorizeFilter::NewL()

    {

    CHuiFxVg10ColorizeFilter* e = new (ELeave) CHuiFxVg10ColorizeFilter();

    CleanupStack::PushL(e);

    e->ConstructL();

    CleanupStack::Pop(e);

    return e;

    }

void CHuiFxVg10ColorizeFilter::ConstructL()

    {

    CHuiFxVg10ColorMatrixFilterBase::ConstructL();

    iColor = TRgb(0xffffffff);

    RegisterParameterL(KLitColor, &iColor);

    }

CHuiFxVg10ColorizeFilter *CHuiFxVg10ColorizeFilter::CloneL() const

    {

    CHuiFxVg10ColorizeFilter *filter = new(ELeave)CHuiFxVg10ColorizeFilter;

    filter->CHuiFxVg10ColorMatrixFilterBase::CopyFromL(this);

    filter->iColor = iColor;

    filter->CopyParameterL(KLitColor, &filter->iColor, this);

    return filter;

    }

void CHuiFxVg10ColorizeFilter::UpdateColorMatrix(void)

    {

    const VGfloat o = clamp(iOpacity, 0.0f, 1.0f);

    const VGfloat ao = 1 - o;

    const VGfloat Rw = 0.3086f;

    const VGfloat Gw = 0.6094f;

    const VGfloat Bw = 0.0820f;

    const VGfloat R = (o / 255.0f) * (VGfloat)iColor.Red();

    const VGfloat G = (o / 255.0f) * (VGfloat)iColor.Green();

    const VGfloat B = (o / 255.0f) * (VGfloat)iColor.Blue();

    // this matrix is ((I * (1 - opacity)) + (I * opacity) * RGBMatrix * desaturateMatrix)T

    // i.e. pixel is first converted to luminance, then multiplied by RGB, multiplied by opacity and finally the diagonal

    // compensated with 1 - opacity.

    // Precalculating abovementioned matrices to single matrix saves over a magnitude of multiplications and

    // almost two magnitudes of additions. Also less memory is used and no unnecessary copying is involved.

    iColorMatrix[0] = R*Rw + ao;

    iColorMatrix[1] = G*Rw;

    iColorMatrix[2] = B*Rw;

    iColorMatrix[3] = 0.0f;

    iColorMatrix[4] = R*Gw;

    iColorMatrix[5] = G*Gw + ao;

    iColorMatrix[6] = B*Gw;

    iColorMatrix[7] = 0.0f;

    iColorMatrix[8] = R*Bw;

    iColorMatrix[9] = G*Bw;

    iColorMatrix[10] = B*Bw + ao;

    iColorMatrix[11] = 0.0f;

    iColorMatrix[12] = 0.0f;

    iColorMatrix[13] = 0.0f;

    iColorMatrix[14] = 0.0f;

    iColorMatrix[15] = 1.0f;

    iColorMatrix[16] = 0.0f;

    iColorMatrix[17] = 0.0f;

    iColorMatrix[18] = 0.0f;

    iColorMatrix[19] = 0.0f;    

    }