GainDataspace.cpp

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/** @file
 *
 * @ingroup foundationDataspaceLib
 *
 * @brief The #GainDataspace converts between different measurement untis describing audio gain.
 *
 * @details The neutral unit of the gain dataspace is _linear gain_.
 *
 * @authors Trond Lossius, Tim Place, Nils Peters, ...
 *
 * @copyright Copyright © 2007 by Trond Lossius @n
 * This code is licensed under the terms of the "New BSD License" @n
 * http://creativecommons.org/licenses/BSD/
 */


#include "GainDataspace.h"
#include <math.h>


#define thisTTClass         LinearAmplitudeUnit
#define thisTTClassName     "unit.linear"
#define thisTTClassTags     "dataspace.unit, gain"

TT_OBJECT_CONSTRUCTOR,
TTDataspaceUnit(arguments)
{;}

LinearAmplitudeUnit::~LinearAmplitudeUnit(){;}      

void LinearAmplitudeUnit::convertToNeutral(const TTValue& input, TTValue& output)
{
    output = input;
    output.cliplow(0.0);
}


void LinearAmplitudeUnit::convertFromNeutral(const TTValue& input, TTValue& output)
{
    output = input;
}


#undef thisTTClass
#undef thisTTClassName
#undef thisTTClassTags

/***********************************************************************************************/

#define thisTTClass         MidiGainUnit
#define thisTTClassName     "unit.midi.gain"
#define thisTTClassTags     "dataspace.unit, gain"

TT_OBJECT_CONSTRUCTOR,
TTDataspaceUnit(arguments)
{;}

MidiGainUnit::~MidiGainUnit(){;}        

void MidiGainUnit::convertToNeutral(const TTValue& input, TTValue& output)
{
    output = pow(TTFloat64(input)*0.01, kTTGainMidiPower);
}


void MidiGainUnit::convertFromNeutral(const TTValue& input, TTValue& output)
{
    output = 100.0 * pow(TTFloat64(input), kTTGainMidiPowerInv);
}


#undef thisTTClass
#undef thisTTClassName
#undef thisTTClassTags

/***********************************************************************************************/

#define thisTTClass         DecibelUnit
#define thisTTClassName     "unit.db"
#define thisTTClassTags     "dataspace.unit, gain"

TT_OBJECT_CONSTRUCTOR,
TTDataspaceUnit(arguments)
{;}

DecibelUnit::~DecibelUnit(){;}      

void DecibelUnit::convertToNeutral(const TTValue& input, TTValue& output)
{
    output = pow(10.0, TTFloat64(input) * 0.05);
}


void DecibelUnit::convertFromNeutral(const TTValue& input, TTValue& output)
{
    TTFloat64 temp;
    
    // The conversion
    temp = log10(TTFloat64(input)) * 20.0;
    
    // Output decibel range is limited to 24 bit range, avoids problems with singularities (-inf) when using dataspace in ramps
    if (temp < -144.49)
        temp = -144.49;
    output = temp;
}


#undef thisTTClass
#undef thisTTClassName
#undef thisTTClassTags

/***********************************************************************************************/

#define thisTTClass         GainDataspace
#define thisTTClassName     "dataspace.gain"
#define thisTTClassTags     "foundationDataspaceLib, dataspace, gain"

TT_OBJECT_CONSTRUCTOR
{
    // Create one of each kind of unit, and cache them in a hash
    registerUnit(TT("unit.linear"),     TT("linear"));
    registerUnit(TT("unit.midi.gain"),  TT("midigain"));
    registerUnit(TT("unit.db"),         TT("dB"));
    registerUnit(TT("unit.db"),         TT("db"));

    // Set our neutral unit (the unit through which all conversions are made)
    neutralUnit = TT("linear");
    
    // Now that the cache is created, we can create a set of default units
    setInputUnit(neutralUnit);
    setOutputUnit(neutralUnit);
}


GainDataspace::~GainDataspace()
{
    ;
}

#undef thisTTClass
#undef thisTTClassName
#undef thisTTClassTags