delaybuffer.h

/** DelayBuffer (adds delay to a buffer)
 * Copyright (C) Madura A.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General
 * Public License along with this program; if not, write to the
 * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02111-1307, USA.
 */
#pragma once

#include <cstring>
#include <stdlib.h>
template <typename T>
class DelayBuffer {
private:
    T *_buffer;
    int _buffer_size;

public:
    DelayBuffer(int buffer_size) : _buffer(new T[buffer_size * sizeof(T)]), _buffer_size(buffer_size) {
        memset(_buffer, 0, buffer_size * sizeof(T));
    }
    void FillDelayed(T *in_buffer, T *out_buffer, int delay) {
        for (int i = 0; i < delay; i++) {
            out_buffer[i] = _buffer[i];
            _buffer[i] = in_buffer[_buffer_size - delay + i];
        }
        for (int i = delay; i < _buffer_size; i++) {
            out_buffer[i] = in_buffer[i - delay];
        }
    }
    void MixDelayed(T *in_buffer, T *out_buffer, int delay, float gain) {
        for (int i = 0; i < delay; i++) {
            out_buffer[i] += _buffer[i] * gain;
            out_buffer[i] *= 0.5;
            _buffer[i] = in_buffer[_buffer_size - delay + i];
        }
        for (int i = delay; i < _buffer_size; i++) {
            out_buffer[i] += in_buffer[i - delay] * gain;
            out_buffer[i] *= 0.5;
        }
    }
    ~DelayBuffer() { delete[] _buffer; }
};