Files
lmms/plugins/Flanger/FlangerEffect.cpp
2017-11-22 11:08:47 +01:00

152 lines
3.9 KiB
C++

/*
* flangereffect.cpp - defination of FlangerEffect class.
*
* Copyright (c) 2014 David French <dave/dot/french3/at/googlemail/dot/com>
*
* This file is part of LMMS - https://lmms.io
*
* This program 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.
*
* This program 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 this program (see COPYING); if not, write to the
* Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301 USA.
*
*/
#include "FlangerEffect.h"
#include "Engine.h"
#include "embed.h"
extern "C"
{
Plugin::Descriptor PLUGIN_EXPORT flanger_plugin_descriptor =
{
STRINGIFY( PLUGIN_NAME ),
"Flanger",
QT_TRANSLATE_NOOP( "pluginBrowser", "A native flanger plugin" ),
"Dave French <contact/dot/dave/dot/french3/at/googlemail/dot/com>",
0x0100,
Plugin::Effect,
new PluginPixmapLoader("logo"),
NULL,
NULL
} ;
FlangerEffect::FlangerEffect( Model *parent, const Plugin::Descriptor::SubPluginFeatures::Key *key ) :
Effect( &flanger_plugin_descriptor, parent, key ),
m_flangerControls( this )
{
m_lfo = new QuadratureLfo( Engine::mixer()->processingSampleRate() );
m_lDelay = new MonoDelay( 1, Engine::mixer()->processingSampleRate() );
m_rDelay = new MonoDelay( 1, Engine::mixer()->processingSampleRate() );
m_noise = new Noise;
}
FlangerEffect::~FlangerEffect()
{
if(m_lDelay )
{
delete m_lDelay;
}
if( m_rDelay )
{
delete m_rDelay;
}
if(m_lfo )
{
delete m_lfo;
}
if(m_noise)
{
delete m_noise;
}
}
bool FlangerEffect::processAudioBuffer( sampleFrame *buf, const fpp_t frames )
{
if( !isEnabled() || !isRunning () )
{
return( false );
}
double outSum = 0.0;
const float d = dryLevel();
const float w = wetLevel();
const float length = m_flangerControls.m_delayTimeModel.value() * Engine::mixer()->processingSampleRate();
const float noise = m_flangerControls.m_whiteNoiseAmountModel.value();
float amplitude = m_flangerControls.m_lfoAmountModel.value() * Engine::mixer()->processingSampleRate();
bool invertFeedback = m_flangerControls.m_invertFeedbackModel.value();
m_lfo->setFrequency( 1.0/m_flangerControls.m_lfoFrequencyModel.value() );
m_lDelay->setFeedback( m_flangerControls.m_feedbackModel.value() );
m_rDelay->setFeedback( m_flangerControls.m_feedbackModel.value() );
sample_t dryS[2];
float leftLfo;
float rightLfo;
for( fpp_t f = 0; f < frames; ++f )
{
buf[f][0] += m_noise->tick() * noise;
buf[f][1] += m_noise->tick() * noise;
dryS[0] = buf[f][0];
dryS[1] = buf[f][1];
m_lfo->tick(&leftLfo, &rightLfo);
m_lDelay->setLength( ( float )length + amplitude * (leftLfo+1.0) );
m_rDelay->setLength( ( float )length + amplitude * (rightLfo+1.0) );
if(invertFeedback)
{
m_lDelay->tick( &buf[f][1] );
m_rDelay->tick(&buf[f][0] );
} else
{
m_lDelay->tick( &buf[f][0] );
m_rDelay->tick( &buf[f][1] );
}
buf[f][0] = ( d * dryS[0] ) + ( w * buf[f][0] );
buf[f][1] = ( d * dryS[1] ) + ( w * buf[f][1] );
outSum += buf[f][0]*buf[f][0] + buf[f][1]*buf[f][1];
}
checkGate( outSum / frames );
return isRunning();
}
void FlangerEffect::changeSampleRate()
{
m_lfo->setSampleRate( Engine::mixer()->processingSampleRate() );
m_lDelay->setSampleRate( Engine::mixer()->processingSampleRate() );
m_rDelay->setSampleRate( Engine::mixer()->processingSampleRate() );
}
extern "C"
{
//needed for getting plugin out of shared lib
PLUGIN_EXPORT Plugin * lmms_plugin_main( Model* parent, void* data )
{
return new FlangerEffect( parent , static_cast<const Plugin::Descriptor::SubPluginFeatures::Key *>( data ) );
}
}}