asid/plugin/plugin.h

108 lines
3.6 KiB
C

/*
* Tibia
*
* Copyright (C) 2023, 2024 Orastron Srl unipersonale
*
* Tibia 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.
*
* Tibia 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 Tibia. If not, see <http://www.gnu.org/licenses/>.
*
* File author: Stefano D'Angelo
*/
#include "asid.h"
typedef struct plugin {
asid instance;
} plugin;
static void plugin_init(plugin *instance) {
instance->instance = asid_new();
}
static void plugin_fini(plugin *instance) {
(void)instance;
}
static void plugin_set_sample_rate(plugin *instance, float sample_rate) {
instance->sample_rate = sample_rate;
//safe approx instance->delay_line_length = ceilf(sample_rate) + 1;
instance->delay_line_length = (size_t)(sample_rate + 1.f) + 1;
}
static size_t plugin_mem_req(plugin *instance) {
return instance->delay_line_length * sizeof(float);
}
static void plugin_mem_set(plugin *instance, void *mem) {
instance->delay_line = (float *)mem;
}
static void plugin_reset(plugin *instance) {
for (size_t i = 0; i < instance->delay_line_length; i++)
instance->delay_line[i] = 0.f;
instance->delay_line_cur = 0;
instance->z1 = 0.f;
instance->cutoff_k = 1.f;
instance->yz1 = 0.f;
}
static void plugin_set_parameter(plugin *instance, size_t index, float value) {
switch (index) {
case 0:
//approx instance->gain = powf(10.f, 0.05f * value);
instance->gain = ((2.6039890429412597e-4f * value + 0.032131027163547855f) * value + 1.f) / ((0.0012705124328080768f * value - 0.0666763481312185f) * value + 1.f);
break;
case 1:
instance->delay = 0.001f * value;
break;
case 2:
instance->cutoff = value;
break;
case 3:
instance->bypass = value >= 0.5f;
break;
}
}
static float plugin_get_parameter(plugin *instance, size_t index) {
(void)index;
return instance->yz1;
}
static size_t calc_index(size_t cur, size_t delay, size_t len) {
return (cur < delay ? cur + len : cur) - delay;
}
static void plugin_process(plugin *instance, const float **inputs, float **outputs, size_t n_samples) {
//approx size_t delay = roundf(instance->sample_rate * instance->delay);
size_t delay = (size_t)(instance->sample_rate * instance->delay + 0.5f);
const float mA1 = instance->sample_rate / (instance->sample_rate + 6.283185307179586f * instance->cutoff * instance->cutoff_k);
for (size_t i = 0; i < n_samples; i++) {
instance->delay_line[instance->delay_line_cur] = inputs[0][i];
const float x = instance->delay_line[calc_index(instance->delay_line_cur, delay, instance->delay_line_length)];
instance->delay_line_cur++;
if (instance->delay_line_cur == instance->delay_line_length)
instance->delay_line_cur = 0;
const float y = x + mA1 * (instance->z1 - x);
instance->z1 = y;
outputs[0][i] = instance->bypass ? inputs[0][i] : instance->gain * y;
instance->yz1 = outputs[0][i];
}
}
static void plugin_midi_msg_in(plugin *instance, size_t index, const uint8_t * data) {
(void)index;
if (((data[0] & 0xf0) == 0x90) && (data[2] != 0))
//approx instance->cutoff_k = powf(2.f, (1.f / 12.f) * (note - 60));
instance->cutoff_k = data[1] < 64 ? (-0.19558034980097166f * data[1] - 2.361735109225749f) / (data[1] - 75.57552349522389f) : (393.95397927344214f - 7.660826245588588f * data[1]) / (data[1] - 139.0755234952239f);
}