/*

     File: CAVolumeCurve.cpp

 Abstract: CAVolumeCurve.h

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//=============================================================================

//  Includes

//=============================================================================

#include "CAVolumeCurve.h"

#include "CADebugMacros.h"

#include <math.h>

//=============================================================================

//  CAVolumeCurve

//=============================================================================

CAVolumeCurve::CAVolumeCurve()

:

    mTag(0),

    mCurveMap(),

    mIsApplyingTransferFunction(true),

    mTransferFunction(kPow2Over1Curve),

    mRawToScalarExponentNumerator(2.0f),

    mRawToScalarExponentDenominator(1.0f)

{

}

CAVolumeCurve::~CAVolumeCurve()

{

}

SInt32  CAVolumeCurve::GetMinimumRaw() const

{

    SInt32 theAnswer = 0;

    if(!mCurveMap.empty())

    {

        CurveMap::const_iterator theIterator = mCurveMap.begin();

        theAnswer = theIterator->first.mMinimum;

    }

    return theAnswer;

}

SInt32  CAVolumeCurve::GetMaximumRaw() const

{

    SInt32 theAnswer = 0;

    if(!mCurveMap.empty())

    {

        CurveMap::const_iterator theIterator = mCurveMap.begin();

        std::advance(theIterator, static_cast<int>(mCurveMap.size() - 1));

        theAnswer = theIterator->first.mMaximum;

    }

    return theAnswer;

}

Float32 CAVolumeCurve::GetMinimumDB() const

{

    Float32 theAnswer = 0;

    if(!mCurveMap.empty())

    {

        CurveMap::const_iterator theIterator = mCurveMap.begin();

        theAnswer = theIterator->second.mMinimum;

    }

    return theAnswer;

}

Float32 CAVolumeCurve::GetMaximumDB() const

{

    Float32 theAnswer = 0;

    if(!mCurveMap.empty())

    {

        CurveMap::const_iterator theIterator = mCurveMap.begin();

        std::advance(theIterator, static_cast<int>(mCurveMap.size() - 1));

        theAnswer = theIterator->second.mMaximum;

    }

    return theAnswer;

}

void    CAVolumeCurve::SetTransferFunction(UInt32 inTransferFunction)

{

    mTransferFunction = inTransferFunction;

    //  figure out the co-efficients

    switch(inTransferFunction)

    {

        case kLinearCurve:

            mIsApplyingTransferFunction = false;

            mRawToScalarExponentNumerator = 1.0f;

            mRawToScalarExponentDenominator = 1.0f;

            break;

        case kPow1Over3Curve:

            mIsApplyingTransferFunction = true;

            mRawToScalarExponentNumerator = 1.0f;

            mRawToScalarExponentDenominator = 3.0f;

            break;

        case kPow1Over2Curve:

            mIsApplyingTransferFunction = true;

            mRawToScalarExponentNumerator = 1.0f;

            mRawToScalarExponentDenominator = 2.0f;

            break;

        case kPow3Over4Curve:

            mIsApplyingTransferFunction = true;

            mRawToScalarExponentNumerator = 3.0f;

            mRawToScalarExponentDenominator = 4.0f;

            break;

        case kPow3Over2Curve:

            mIsApplyingTransferFunction = true;

            mRawToScalarExponentNumerator = 3.0f;

            mRawToScalarExponentDenominator = 2.0f;

            break;

        case kPow2Over1Curve:

            mIsApplyingTransferFunction = true;

            mRawToScalarExponentNumerator = 2.0f;

            mRawToScalarExponentDenominator = 1.0f;

            break;

        case kPow3Over1Curve:

            mIsApplyingTransferFunction = true;

            mRawToScalarExponentNumerator = 3.0f;

            mRawToScalarExponentDenominator = 1.0f;

            break;

        case kPow4Over1Curve:

            mIsApplyingTransferFunction = true;

            mRawToScalarExponentNumerator = 4.0f;

            mRawToScalarExponentDenominator = 1.0f;

            break;

        case kPow5Over1Curve:

            mIsApplyingTransferFunction = true;

            mRawToScalarExponentNumerator = 5.0f;

            mRawToScalarExponentDenominator = 1.0f;

            break;

        case kPow6Over1Curve:

            mIsApplyingTransferFunction = true;

            mRawToScalarExponentNumerator = 6.0f;

            mRawToScalarExponentDenominator = 1.0f;

            break;

        case kPow7Over1Curve:

            mIsApplyingTransferFunction = true;

            mRawToScalarExponentNumerator = 7.0f;

            mRawToScalarExponentDenominator = 1.0f;

            break;

        case kPow8Over1Curve:

            mIsApplyingTransferFunction = true;

            mRawToScalarExponentNumerator = 8.0f;

            mRawToScalarExponentDenominator = 1.0f;

            break;

        case kPow9Over1Curve:

            mIsApplyingTransferFunction = true;

            mRawToScalarExponentNumerator = 9.0f;

            mRawToScalarExponentDenominator = 1.0f;

            break;

        case kPow10Over1Curve:

            mIsApplyingTransferFunction = true;

            mRawToScalarExponentNumerator = 10.0f;

            mRawToScalarExponentDenominator = 1.0f;

            break;

        case kPow11Over1Curve:

            mIsApplyingTransferFunction = true;

            mRawToScalarExponentNumerator = 11.0f;

            mRawToScalarExponentDenominator = 1.0f;

            break;

        case kPow12Over1Curve:

            mIsApplyingTransferFunction = true;

            mRawToScalarExponentNumerator = 12.0f;

            mRawToScalarExponentDenominator = 1.0f;

            break;

        default:

            mIsApplyingTransferFunction = true;

            mRawToScalarExponentNumerator = 2.0f;

            mRawToScalarExponentDenominator = 1.0f;

            break;

    };

}

void    CAVolumeCurve::AddRange(SInt32 inMinRaw, SInt32 inMaxRaw, Float32 inMinDB, Float32 inMaxDB)

{

    CARawPoint theRaw(inMinRaw, inMaxRaw);

    CADBPoint theDB(inMinDB, inMaxDB);

    bool isOverlapped = false;

    bool isDone = false;

    CurveMap::iterator theIterator = mCurveMap.begin();

    while((theIterator != mCurveMap.end()) && !isOverlapped && !isDone)

    {

        isOverlapped = CARawPoint::Overlap(theRaw, theIterator->first);

        isDone = theRaw >= theIterator->first;

        if(!isOverlapped && !isDone)

        {

            std::advance(theIterator, 1);

        }

    }

    if(!isOverlapped)

    {

        mCurveMap.insert(CurveMap::value_type(theRaw, theDB));

    }

    else

    {

        DebugMessage("CAVolumeCurve::AddRange: new point overlaps");

    }

}

void    CAVolumeCurve::ResetRange()

{

    mCurveMap.clear();

}

bool    CAVolumeCurve::CheckForContinuity() const

{

    bool theAnswer = true;

    CurveMap::const_iterator theIterator = mCurveMap.begin();

    if(theIterator != mCurveMap.end())

    {

        SInt32 theRaw = theIterator->first.mMinimum;

        Float32 theDB = theIterator->second.mMinimum;

        do

        {

            SInt32 theRawMin = theIterator->first.mMinimum;

            SInt32 theRawMax = theIterator->first.mMaximum;

            SInt32 theRawRange = theRawMax - theRawMin;

            Float32 theDBMin = theIterator->second.mMinimum;

            Float32 theDBMax = theIterator->second.mMaximum;

            Float32 theDBRange = theDBMax - theDBMin;

            theAnswer = theRaw == theRawMin;

            theAnswer = theAnswer && (theDB == theDBMin);

            theRaw += theRawRange;

            theDB += theDBRange;

            std::advance(theIterator, 1);

        }

        while((theIterator != mCurveMap.end()) && theAnswer);

    }

    return theAnswer;

}

SInt32  CAVolumeCurve::ConvertDBToRaw(Float32 inDB) const

{

    //  clamp the value to the dB range

    Float32 theOverallDBMin = GetMinimumDB();

    Float32 theOverallDBMax = GetMaximumDB();

    if(inDB < theOverallDBMin) inDB = theOverallDBMin;

    if(inDB > theOverallDBMax) inDB = theOverallDBMax;

    //  get the first entry in the curve map;

    CurveMap::const_iterator theIterator = mCurveMap.begin();

    //  initialize the answer to the minimum raw of the first item in the curve map

    SInt32 theAnswer = theIterator->first.mMinimum;

    //  iterate through the curve map until we run out of dB

    bool isDone = false;

    while(!isDone && (theIterator != mCurveMap.end()))

    {

        SInt32 theRawMin = theIterator->first.mMinimum;

        SInt32 theRawMax = theIterator->first.mMaximum;

        SInt32 theRawRange = theRawMax - theRawMin;

        Float32 theDBMin = theIterator->second.mMinimum;

        Float32 theDBMax = theIterator->second.mMaximum;

        Float32 theDBRange = theDBMax - theDBMin;

        Float32 theDBPerRaw = theDBRange / static_cast<Float32>(theRawRange);

        //  figure out how many steps we are into this entry in the curve map

        if(inDB > theDBMax)

        {

            //  we're past the end of this one, so add in the whole range for this entry

            theAnswer += theRawRange;

        }

        else

        {

            //  it's somewhere within the current entry

            //  figure out how many steps it is

            Float32 theNumberRawSteps = inDB - theDBMin;

            theNumberRawSteps /= theDBPerRaw;

            //  only move in whole steps

            theNumberRawSteps = roundf(theNumberRawSteps);

            //  add this many steps to the answer

            theAnswer += static_cast<SInt32>(theNumberRawSteps);

            //  mark that we are done

            isDone = true;

        }

        //  go to the next entry in the curve map

        std::advance(theIterator, 1);

    }

    return theAnswer;

}

Float32 CAVolumeCurve::ConvertRawToDB(SInt32 inRaw) const

{

    Float32 theAnswer = 0;

    //  clamp the raw value

    SInt32 theOverallRawMin = GetMinimumRaw();

    SInt32 theOverallRawMax = GetMaximumRaw();

    if(inRaw < theOverallRawMin) inRaw = theOverallRawMin;

    if(inRaw > theOverallRawMax) inRaw = theOverallRawMax;

    //  figure out how many raw steps need to be taken from the first one

    SInt32 theNumberRawSteps = inRaw - theOverallRawMin;

    //  get the first item in the curve map

    CurveMap::const_iterator theIterator = mCurveMap.begin();

    //  initialize the answer to the minimum dB of the first item in the curve map

    theAnswer = theIterator->second.mMinimum;

    //  iterate through the curve map until we run out of steps

    while((theNumberRawSteps > 0) && (theIterator != mCurveMap.end()))

    {

        //  compute some values

        SInt32 theRawMin = theIterator->first.mMinimum;

        SInt32 theRawMax = theIterator->first.mMaximum;

        SInt32 theRawRange = theRawMax - theRawMin;

        Float32 theDBMin = theIterator->second.mMinimum;

        Float32 theDBMax = theIterator->second.mMaximum;

        Float32 theDBRange = theDBMax - theDBMin;

        Float32 theDBPerRaw = theDBRange / static_cast<Float32>(theRawRange);

        //  there might be more steps than the current map entry accounts for

        SInt32 theRawStepsToAdd = std::min(theRawRange, theNumberRawSteps);

        //  add this many steps worth of db to the answer;

        theAnswer += theRawStepsToAdd * theDBPerRaw;

        //  figure out how many steps are left

        theNumberRawSteps -= theRawStepsToAdd;

        //  go to the next map entry

        std::advance(theIterator, 1);

    }

    return theAnswer;

}

Float32 CAVolumeCurve::ConvertRawToScalar(SInt32 inRaw) const

{

    //  get some important values

    Float32 theDBMin = GetMinimumDB();

    Float32 theDBMax = GetMaximumDB();

    Float32 theDBRange = theDBMax - theDBMin;

    SInt32  theRawMin = GetMinimumRaw();

    SInt32  theRawMax = GetMaximumRaw();

    SInt32  theRawRange = theRawMax - theRawMin;

    //  range the raw value

    if(inRaw < theRawMin) inRaw = theRawMin;

    if(inRaw > theRawMax) inRaw = theRawMax;

    //  calculate the distance in the range inRaw is

    Float32 theAnswer = static_cast<Float32>(inRaw - theRawMin) / static_cast<Float32>(theRawRange);

    //  only apply a curve to the scalar values if the dB range is greater than 30

    if(mIsApplyingTransferFunction && (theDBRange > 30.0f))

    {

        theAnswer = powf(theAnswer, mRawToScalarExponentNumerator / mRawToScalarExponentDenominator);

    }

    return theAnswer;

}

Float32 CAVolumeCurve::ConvertDBToScalar(Float32 inDB) const

{

    SInt32 theRawValue = ConvertDBToRaw(inDB);

    Float32 theAnswer = ConvertRawToScalar(theRawValue);

    return theAnswer;

}

SInt32  CAVolumeCurve::ConvertScalarToRaw(Float32 inScalar) const

{

    //  range the scalar value

    inScalar = std::min(1.0f, std::max(0.0f, inScalar));

    //  get some important values

    Float32 theDBMin = GetMinimumDB();

    Float32 theDBMax = GetMaximumDB();

    Float32 theDBRange = theDBMax - theDBMin;

    SInt32  theRawMin = GetMinimumRaw();

    SInt32  theRawMax = GetMaximumRaw();

    SInt32  theRawRange = theRawMax - theRawMin;

    //  have to undo the curve if the dB range is greater than 30

    if(mIsApplyingTransferFunction && (theDBRange > 30.0f))

    {

        inScalar = powf(inScalar, mRawToScalarExponentDenominator / mRawToScalarExponentNumerator);

    }

    //  now we can figure out how many raw steps this is

    Float32 theNumberRawSteps = inScalar * static_cast<Float32>(theRawRange);

    theNumberRawSteps = roundf(theNumberRawSteps);

    //  the answer is the minimum raw value plus the number of raw steps

    SInt32 theAnswer = theRawMin + static_cast<SInt32>(theNumberRawSteps);

    return theAnswer;

}

Float32 CAVolumeCurve::ConvertScalarToDB(Float32 inScalar) const

{

    SInt32 theRawValue = ConvertScalarToRaw(inScalar);

    Float32 theAnswer = ConvertRawToDB(theRawValue);

    return theAnswer;

}