brickworks/include/bw_ring_mod.h

307 lines
9.4 KiB
C++

/*
* Brickworks
*
* Copyright (C) 2023 Orastron Srl unipersonale
*
* Brickworks 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, version 3 of the License.
*
* Brickworks 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 Brickworks. If not, see <http://www.gnu.org/licenses/>.
*
* File author: Stefano D'Angelo
*/
/*!
* module_type {{{ dsp }}}
* version {{{ 1.0.0 }}}
* requires {{{ bw_common bw_math bw_one_pole }}}
* description {{{
* Ring modulator with variable modulation amount.
* }}}
* changelog {{{
* <ul>
* <li>Version <strong>1.0.0</strong>:
* <ul>
* <li>Module renamed as bw_ring_mod.</li>
* <li><code>bw_ring_mod_process()</code> and
* <code>bw_ring_mod_process_multi()</code> now use
* <code>size_t</code> to count samples and channels.</li>
* <li>Added more <code>const</code> specifiers to input
* arguments.</li>
* <li>Moved C++ code to C header.</li>
* <li>Added overladed C++ <code>process()</code> function taking
* C-style arrays as arguments.</li>
* <li>Removed usage of reserved identifiers.</li>
* </ul>
* </li>
* <li>Version <strong>0.6.0</strong>:
* <ul>
* <li>Removed dependency on bw_config.</li>
* </ul>
* </li>
* <li>Version <strong>0.5.0</strong>:
* <ul>
* <li>Added <code>bw_ringmod_process_multi()</code>.</li>
* <li>Fixed inverted-polarity modulation.</li>
* <li>"modulator signal" -> "modulation signal" in documentation.</li>
* <li>Added C++ wrapper.</li>
* </ul>
* </li>
* <li>Version <strong>0.4.0</strong>:
* <ul>
* <li>First release.</li>
* </ul>
* </li>
* </ul>
* }}}
*/
#ifndef BW_RINGMOD_H
#define BW_RINGMOD_H
#include <bw_common.h>
#ifdef __cplusplus
extern "C" {
#endif
/*! api {{{
* #### bw_ring_mod_coeffs
* ```>>> */
typedef struct bw_ring_mod_coeffs bw_ring_mod_coeffs;
/*! <<<```
* Coefficients and related.
*
* #### bw_ring_mod_init()
* ```>>> */
static inline void bw_ring_mod_init(bw_ring_mod_coeffs *BW_RESTRICT coeffs);
/*! <<<```
* Initializes input parameter values in `coeffs`.
*
* #### bw_ring_mod_set_sample_rate()
* ```>>> */
static inline void bw_ring_mod_set_sample_rate(bw_ring_mod_coeffs *BW_RESTRICT coeffs, float sample_rate);
/*! <<<```
* Sets the `sample_rate` (Hz) value in `coeffs`.
*
* #### bw_ring_mod_reset_coeffs()
* ```>>> */
static inline void bw_ring_mod_reset_coeffs(bw_ring_mod_coeffs *BW_RESTRICT coeffs);
/*! <<<```
* Resets coefficients in `coeffs` to assume their target values.
*
* #### bw_ring_mod_update_coeffs_ctrl()
* ```>>> */
static inline void bw_ring_mod_update_coeffs_ctrl(bw_ring_mod_coeffs *BW_RESTRICT coeffs);
/*! <<<```
* Triggers control-rate update of coefficients in `coeffs`.
*
* #### bw_ring_mod_update_coeffs_audio()
* ```>>> */
static inline void bw_ring_mod_update_coeffs_audio(bw_ring_mod_coeffs *BW_RESTRICT coeffs);
/*! <<<```
* Triggers audio-rate update of coefficients in `coeffs`.
*
* #### bw_ring_mod_process1()
* ```>>> */
static inline float bw_ring_mod_process1(const bw_ring_mod_coeffs *BW_RESTRICT coeffs, float x_mod, float x_car);
/*! <<<```
* Processes one modulation input sample `x_mod` and one carrier input sample
* `x_car` using `coeffs` and returns the corresponding output sample.
*
* #### bw_ring_mod_process()
* ```>>> */
static inline void bw_ring_mod_process(bw_ring_mod_coeffs *BW_RESTRICT coeffs, const float *x_mod, const float *x_car, float *y, size_t n_samples);
/*! <<<```
* Processes the first `n_samples` of the modulation input buffer `x_mod` and
* of the carrier input buffer `x_car` and fills the first `n_samples` of the
* output buffer `y`, while using and updating `coeffs` (control and audio
* rate).
*
* #### bw_ring_mod_process_multi()
* ```>>> */
static inline void bw_ring_mod_process_multi(bw_ring_mod_coeffs *BW_RESTRICT coeffs, const float * const *x_mod, const float * const *x_car, float * const *y, size_t n_channels, size_t n_samples);
/*! <<<```
* Processes the first `n_samples` of the `n_channels` modulation input
* buffers `x_mod` and of the `n_channels` carrier input buffers `x_car`, and
* fills the first `n_samples` of the `n_channels` output buffers `y`, while
* using and updating the common `coeffs` (control and audio rate).
*
* #### bw_ring_mod_set_amount()
* ```>>> */
static inline void bw_ring_mod_set_amount(bw_ring_mod_coeffs *BW_RESTRICT coeffs, float value);
/*! <<<```
* Sets the modulation amount parameter to the given `value` (`0.f` = no
* modulation, `1.f` = full modulation, `-1.f` = full modulation with
* inverted polarity) in `coeffs`.
*
* Default value: `1.f`.
* }}} */
#ifdef __cplusplus
}
#endif
/*** Implementation ***/
/* WARNING: This part of the file is not part of the public API. Its content may
* change at any time in future versions. Please, do not use it directly. */
#include <bw_math.h>
#include <bw_one_pole.h>
#ifdef __cplusplus
extern "C" {
#endif
struct bw_ring_mod_coeffs {
// Sub-components
bw_one_pole_coeffs smooth_coeffs;
bw_one_pole_state smooth_state;
// Parameters
float mod_amount;
};
static inline void bw_ring_mod_init(bw_ring_mod_coeffs *BW_RESTRICT coeffs) {
bw_one_pole_init(&coeffs->smooth_coeffs);
bw_one_pole_set_tau(&coeffs->smooth_coeffs, 0.05f);
coeffs->mod_amount = 1.f;
}
static inline void bw_ring_mod_set_sample_rate(bw_ring_mod_coeffs *BW_RESTRICT coeffs, float sample_rate) {
bw_one_pole_set_sample_rate(&coeffs->smooth_coeffs, sample_rate);
bw_one_pole_reset_coeffs(&coeffs->smooth_coeffs);
}
static inline void bw_ring_mod_reset_coeffs(bw_ring_mod_coeffs *BW_RESTRICT coeffs) {
bw_one_pole_reset_state(&coeffs->smooth_coeffs, &coeffs->smooth_state, coeffs->mod_amount);
}
static inline void bw_ring_mod_update_coeffs_ctrl(bw_ring_mod_coeffs *BW_RESTRICT coeffs) {
(void)coeffs;
}
static inline void bw_ring_mod_update_coeffs_audio(bw_ring_mod_coeffs *BW_RESTRICT coeffs) {
bw_one_pole_process1(&coeffs->smooth_coeffs, &coeffs->smooth_state, coeffs->mod_amount);
}
static inline float bw_ring_mod_process1(const bw_ring_mod_coeffs *BW_RESTRICT coeffs, float x_mod, float x_car) {
const float k = bw_one_pole_get_y_z1(&coeffs->smooth_state);
return k * x_car * x_mod + bw_absf(1.f - k) * x_mod;
}
static inline void bw_ring_mod_process(bw_ring_mod_coeffs *BW_RESTRICT coeffs, const float *x_mod, const float *x_car, float *y, size_t n_samples) {
for (size_t i = 0; i < n_samples; i++) {
bw_ring_mod_update_coeffs_audio(coeffs);
y[i] = bw_ring_mod_process1(coeffs, x_mod[i], x_car[i]);
}
}
static inline void bw_ring_mod_process_multi(bw_ring_mod_coeffs *BW_RESTRICT coeffs, const float * const *x_mod, const float * const *x_car, float * const *y, size_t n_channels, size_t n_samples) {
for (size_t i = 0; i < n_samples; i++) {
bw_ring_mod_update_coeffs_audio(coeffs);
for (size_t j = 0; j < n_channels; j++)
y[j][i] = bw_ring_mod_process1(coeffs, x_mod[j][i], x_car[j][i]);
}
}
static inline void bw_ring_mod_set_amount(bw_ring_mod_coeffs *BW_RESTRICT coeffs, float value) {
coeffs->mod_amount = value;
}
#ifdef __cplusplus
}
#include <array>
namespace Brickworks {
/*** Public C++ API ***/
/*! api_cpp {{{
* ##### Brickworks::RingMod
* ```>>> */
template<size_t N_CHANNELS>
class RingMod {
public:
RingMod();
void setSampleRate(float sampleRate);
void reset();
void process(
const float * const *x_mod,
const float * const *x_car,
float * const *y,
size_t nSamples);
void process(
std::array<const float *, N_CHANNELS> x_mod,
std::array<const float *, N_CHANNELS> x_car,
std::array<float *, N_CHANNELS> y,
size_t nSamples);
void setAmount(float value);
/*! <<<...
* }
* ```
* }}} */
/*** Implementation ***/
/* WARNING: This part of the file is not part of the public API. Its content may
* change at any time in future versions. Please, do not use it directly. */
private:
bw_ring_mod_coeffs coeffs;
};
template<size_t N_CHANNELS>
inline RingMod<N_CHANNELS>::RingMod() {
bw_ring_mod_init(&coeffs);
}
template<size_t N_CHANNELS>
inline void RingMod<N_CHANNELS>::setSampleRate(float sampleRate) {
bw_ring_mod_set_sample_rate(&coeffs, sampleRate);
}
template<size_t N_CHANNELS>
inline void RingMod<N_CHANNELS>::reset() {
bw_ring_mod_reset_coeffs(&coeffs);
}
template<size_t N_CHANNELS>
inline void RingMod<N_CHANNELS>::process(
const float * const *x_mod,
const float * const *x_car,
float * const *y,
size_t nSamples) {
bw_ring_mod_process_multi(&coeffs, x_mod, x_car, y, N_CHANNELS, nSamples);
}
template<size_t N_CHANNELS>
inline void RingMod<N_CHANNELS>::process(
std::array<const float *, N_CHANNELS> x_mod,
std::array<const float *, N_CHANNELS> x_car,
std::array<float *, N_CHANNELS> y,
size_t nSamples) {
process(x_mod.data(), x_car.data(), y.data(), nSamples);
}
template<size_t N_CHANNELS>
inline void RingMod<N_CHANNELS>::setAmount(float value) {
bw_ring_mod_set_amount(&coeffs, value);
}
}
#endif
#endif