forked from bartvdbraak/blender
83 lines
2.4 KiB
C++
83 lines
2.4 KiB
C++
/*
|
|
* ***** BEGIN GPL LICENSE BLOCK *****
|
|
*
|
|
* Copyright 2009-2011 Jörg Hermann Müller
|
|
*
|
|
* This file is part of AudaSpace.
|
|
*
|
|
* Audaspace is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* AudaSpace is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with Audaspace; if not, write to the Free Software Foundation,
|
|
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
|
|
*
|
|
* ***** END GPL LICENSE BLOCK *****
|
|
*/
|
|
|
|
/** \file audaspace/FX/AUD_EnvelopeFactory.cpp
|
|
* \ingroup audfx
|
|
*/
|
|
|
|
|
|
#include "AUD_EnvelopeFactory.h"
|
|
#include "AUD_CallbackIIRFilterReader.h"
|
|
|
|
#include <cmath>
|
|
|
|
struct EnvelopeParameters
|
|
{
|
|
float attack;
|
|
float release;
|
|
float threshold;
|
|
float arthreshold;
|
|
};
|
|
|
|
sample_t AUD_EnvelopeFactory::envelopeFilter(AUD_CallbackIIRFilterReader* reader, EnvelopeParameters* param)
|
|
{
|
|
float in = fabs(reader->x(0));
|
|
float out = reader->y(-1);
|
|
if(in < param->threshold)
|
|
in = 0.0f;
|
|
return (in > out ? param->attack : param->release) * (out - in) + in;
|
|
}
|
|
|
|
void AUD_EnvelopeFactory::endEnvelopeFilter(EnvelopeParameters* param)
|
|
{
|
|
delete param;
|
|
}
|
|
|
|
AUD_EnvelopeFactory::AUD_EnvelopeFactory(boost::shared_ptr<AUD_IFactory> factory, float attack,
|
|
float release, float threshold,
|
|
float arthreshold) :
|
|
AUD_EffectFactory(factory),
|
|
m_attack(attack),
|
|
m_release(release),
|
|
m_threshold(threshold),
|
|
m_arthreshold(arthreshold)
|
|
{
|
|
}
|
|
|
|
boost::shared_ptr<AUD_IReader> AUD_EnvelopeFactory::createReader()
|
|
{
|
|
boost::shared_ptr<AUD_IReader> reader = getReader();
|
|
|
|
EnvelopeParameters* param = new EnvelopeParameters();
|
|
param->arthreshold = m_arthreshold;
|
|
param->attack = pow(m_arthreshold, 1.0f/(static_cast<float>(reader->getSpecs().rate) * m_attack));
|
|
param->release = pow(m_arthreshold, 1.0f/(static_cast<float>(reader->getSpecs().rate) * m_release));
|
|
param->threshold = m_threshold;
|
|
|
|
return boost::shared_ptr<AUD_IReader>(new AUD_CallbackIIRFilterReader(reader, 1, 2,
|
|
(doFilterIIR) envelopeFilter,
|
|
(endFilterIIR) endEnvelopeFilter,
|
|
param));
|
|
}
|