MultitapEcho.h

Go to the documentation of this file.

/*
 * MultitapEcho.h - a multitap echo delay plugin
 *
 * Copyright (c) 2014 Vesa Kivimäki <contact/dot/diizy/at/nbl/dot/fi>
 * Copyright (c) 2008-2014 Tobias Doerffel <tobydox/at/users.sourceforge.net>
 *
 * 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.
 *
 */
 
#ifndef MULTITAP_ECHO_H
#define MULTITAP_ECHO_H
 
#include "Effect.h"
#include "MultitapEchoControls.h"
#include "RingBuffer.h"
#include "BasicFilters.h"
 
namespace lmms
{
 
 
class MultitapEchoEffect : public Effect
{
public:
        MultitapEchoEffect( Model* parent, const Descriptor::SubPluginFeatures::Key* key );
        ~MultitapEchoEffect() override;
 
        ProcessStatus processImpl(SampleFrame* buf, const f_cnt_t frames) override;
 
        EffectControls* controls() override
        {
                return &m_controls;
        }
 
private:
        void updateFilters( int begin, int end );
        void runFilter( SampleFrame* dst, SampleFrame* src, StereoOnePole & filter, const f_cnt_t frames );
 
        inline void setFilterFreq( float fc, StereoOnePole & f )
        {
                const float b1 = std::exp(-2 * std::numbers::pi_v<float> * fc);
                f.setCoeffs( 1.0f - b1, b1 );
        }
 
        int m_stages;
 
        MultitapEchoControls m_controls;
        
        float m_amp [32];
        float m_lpFreq [32];
 
        RingBuffer m_buffer;
        StereoOnePole m_filter [32][4];
        
        float m_sampleRate;
        float m_sampleRatio;
        
        SampleFrame* m_work;
 
        friend class MultitapEchoControls;
 
};
 
 
} // namespace lmms
 
#endif