Line data    Source code

       1              : /*
       2              :  * SPDX-License-Identifier: GPL-3.0-only
       3              :  * MuseScore-CLA-applies
       4              :  *
       5              :  * MuseScore Studio
       6              :  * Music Composition & Notation
       7              :  *
       8              :  * Copyright (C) 2023 MuseScore Limited and others
       9              :  *
      10              :  * This program is free software: you can redistribute it and/or modify
      11              :  * it under the terms of the GNU General Public License version 3 as
      12              :  * published by the Free Software Foundation.
      13              :  *
      14              :  * This program is distributed in the hope that it will be useful,
      15              :  * but WITHOUT ANY WARRANTY; without even the implied warranty of
      16              :  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      17              :  * GNU General Public License for more details.
      18              :  *
      19              :  * You should have received a copy of the GNU General Public License
      20              :  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
      21              :  */
      22              : 
      23              : #ifndef MUSE_AUDIO_ALLPASSMODULATEDDELAY_H
      24              : #define MUSE_AUDIO_ALLPASSMODULATEDDELAY_H
      25              : 
      26              : #include "circularsamplebuffer.h"
      27              : 
      28              : namespace muse::audio::fx {
      29              : class AllPassModulatedDelay
      30              : {
      31              : public:
      32            0 :     AllPassModulatedDelay()
      33            0 :     {
      34            0 :     }
      35              : 
      36            0 :     void allocateForMaxDelaySamples(int maxDelaySamples)
      37              :     {
      38            0 :         m_buffer.setSize(maxDelaySamples);
      39            0 :     }
      40              : 
      41            0 :     void setBaseDelay(float samples, float maxModulationOffset)
      42              :     {
      43            0 :         int allocSize = int(samples + maxModulationOffset + 16.f); // some extra space for interpolation
      44            0 :         if (samples != m_baseDelay || allocSize > m_buffer.getAllocatedSize()) {
      45            0 :             allocateForMaxDelaySamples(allocSize);
      46            0 :             m_baseDelay = samples;
      47            0 :             setModOffset(0.f);
      48            0 :             reset();
      49              :         }
      50            0 :     }
      51              : 
      52              :     float getBaseDelay() const
      53              :     {
      54              :         return m_baseDelay;
      55              :     }
      56              : 
      57            0 :     void setModOffset(float smpOffset)
      58              :     {
      59            0 :         float total = -m_baseDelay + smpOffset; // negative!
      60            0 :         float flr = std::floor(total);
      61            0 :         m_modFraction = total - flr;
      62            0 :         m_readOffset = int(flr);
      63            0 :     }
      64              : 
      65            0 :     void writeSampleAndAdvance(float sample)
      66              :     {
      67            0 :         m_buffer.writeOffset0(sample);
      68            0 :         m_buffer.advance(1);
      69            0 :     }
      70              : 
      71            0 :     float readSample()
      72              :     {
      73            0 :         auto res = m_buffer.read(m_readOffset);
      74            0 :         auto x1 = m_buffer.read(m_readOffset + 1);
      75              : 
      76            0 :         res += m_modFraction * (x1 - m_y1);
      77            0 :         m_y1 = res;
      78            0 :         return res;
      79              :     }
      80              : 
      81              :     float processSample(float sample)
      82              :     {
      83              :         writeSampleAndAdvance(sample);
      84              :         return readSample();
      85              :     }
      86              : 
      87            0 :     void reset()
      88              :     {
      89            0 :         m_buffer.reset();
      90            0 :         m_y1 = 0.f;
      91            0 :     }
      92              : 
      93              : private:
      94              :     int m_readOffset = 0;
      95              :     float m_modFraction = 0.f;
      96              :     float m_baseDelay = 0.f;
      97              : 
      98              :     CircularSampleBuffer<float> m_buffer;
      99              :     float m_y1 = 0.f;
     100              : };
     101              : } // namespace muse::audio::fx
     102              : 
     103              : #endif // MUSE_AUDIO_ALLPASSMODULATEDDELAY_H