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+/*
+ An LV2 plugin to generate a random wave of varying frequency and smoothness.
+ Copyright 2011 David Robillard
+ Copyright 2002 Mike Rawes
+
+ This 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 3 of the License, or
+ (at your option) any later version.
+
+ This software 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 software. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <stdlib.h>
+#include "lv2/lv2plug.in/ns/lv2core/lv2.h"
+#include <time.h>
+#include "math_func.h"
+#include "common.h"
+
+#define RANDOM_FREQUENCY 0
+#define RANDOM_SMOOTH 1
+#define RANDOM_OUTPUT 2
+
+typedef struct {
+ float* frequency;
+ float* smooth;
+ float* output;
+ float nyquist;
+ float inv_nyquist;
+ float phase;
+ float value1;
+ float value2;
+} Random;
+
+float inv_rand_max;
+
+static void
+cleanup(LV2_Handle instance)
+{
+ free(instance);
+}
+
+static void
+connect_port(LV2_Handle instance,
+ uint32_t port,
+ void* data)
+{
+ Random* plugin = (Random*)instance;
+
+ switch (port) {
+ case RANDOM_FREQUENCY:
+ plugin->frequency = data;
+ break;
+ case RANDOM_SMOOTH:
+ plugin->smooth = data;
+ break;
+ case RANDOM_OUTPUT:
+ plugin->output = data;
+ break;
+ }
+}
+
+static LV2_Handle
+instantiate(const LV2_Descriptor* descriptor,
+ double sample_rate,
+ const char* bundle_path,
+ const LV2_Feature* const* features)
+{
+ Random* plugin = (Random*)malloc(sizeof(Random));
+
+ srand((int)time((time_t*)0));
+
+ inv_rand_max = 2.0f / (float)RAND_MAX;
+
+ plugin->nyquist = (float)sample_rate / 2.0f;
+ plugin->inv_nyquist = 1.0f / plugin->nyquist;
+
+ plugin->value1 = rand() * inv_rand_max - 1.0f;
+ plugin->value2 = rand() * inv_rand_max - 1.0f;
+
+ return (LV2_Handle)plugin;
+}
+
+static void
+activate(LV2_Handle instance)
+{
+ Random* plugin = (Random*)instance;
+
+ plugin->phase = 0.0f;
+}
+
+static void
+runRandom_fasa_oa(LV2_Handle instance,
+ uint32_t sample_count)
+{
+ Random* plugin = (Random*)instance;
+
+ /* Frequency (Hz) (array of floats of length sample_count) */
+ float* frequency = plugin->frequency;
+
+ /* Wave smoothness (array of floats of length sample_count) */
+ float* smooth = plugin->smooth;
+
+ /* Output (array of floats of length sample_count) */
+ float* output = plugin->output;
+
+ /* Instance data */
+ float nyquist = plugin->nyquist;
+ float inv_nyquist = plugin->inv_nyquist;
+ float phase = plugin->phase;
+ float value1 = plugin->value1;
+ float value2 = plugin->value2;
+
+ float freq;
+ float smth;
+ float interval;
+ float result;
+
+ for (uint32_t s = 0; s < sample_count; ++s) {
+ freq = f_clip(frequency[s], 0.0f, nyquist);
+
+ smth = f_clip(smooth[s], 0.0f, 1.0f);
+ interval = (1.0f - smth) * 0.5f;
+
+ if (phase < interval) {
+ result = 1.0f;
+ } else if (phase > (1.0f - interval)) {
+ result = -1.0f;
+ } else if (interval > 0.0f) {
+ result = COSF((phase - interval) / smth * M_PI);
+ } else {
+ result = COSF(phase * M_PI);
+ }
+
+ result *= (value2 - value1) * 0.5f;
+ result -= (value2 + value1) * 0.5f;
+
+ output[s] = result;
+
+ phase += freq * inv_nyquist;
+ if (phase > 1.0f) {
+ phase -= 1.0f;
+ value1 = value2;
+ value2 = (float)rand() * inv_rand_max - 1.0f;
+ }
+ }
+
+ plugin->phase = phase;
+ plugin->value1 = value1;
+ plugin->value2 = value2;
+}
+
+static void
+runRandom_fasc_oa(LV2_Handle instance,
+ uint32_t sample_count)
+{
+ Random* plugin = (Random*)instance;
+
+ /* Frequency (Hz) (array of floats of length sample_count) */
+ float* frequency = plugin->frequency;
+
+ /* Wave smoothness (float value) */
+ float smooth = f_clip(*(plugin->smooth), 0.0f, 1.0f);
+
+ /* Output (array of floats of length sample_count) */
+ float* output = plugin->output;
+
+ /* Instance data */
+ float nyquist = plugin->nyquist;
+ float inv_nyquist = plugin->inv_nyquist;
+ float phase = plugin->phase;
+ float value1 = plugin->value1;
+ float value2 = plugin->value2;
+
+ float freq;
+ float interval = (1.0f - smooth) * 0.5f;
+ float result;
+
+ for (uint32_t s = 0; s < sample_count; ++s) {
+ freq = f_clip(frequency[s], 0.0f, nyquist);
+
+ if (phase < interval) {
+ result = 1.0f;
+ } else if (phase > (1.0f - interval)) {
+ result = -1.0f;
+ } else if (interval > 0.0f) {
+ result = COSF((phase - interval) / smooth * M_PI);
+ } else {
+ result = COSF(phase * M_PI);
+ }
+
+ result *= (value2 - value1) * 0.5f;
+ result -= (value2 + value1) * 0.5f;
+
+ output[s] = result;
+
+ phase += freq * inv_nyquist;
+ if (phase > 1.0f) {
+ phase -= 1.0f;
+ value1 = value2;
+ value2 = (float)rand() * inv_rand_max - 1.0f;
+ }
+ }
+
+ plugin->phase = phase;
+ plugin->value1 = value1;
+ plugin->value2 = value2;
+}
+
+static void
+runRandom_fcsa_oa(LV2_Handle instance,
+ uint32_t sample_count)
+{
+ Random* plugin = (Random*)instance;
+
+ /* Frequency (Hz) (float value) */
+ float frequency = *(plugin->frequency);
+
+ /* Wave smoothness (array of floats of length sample_count) */
+ float* smooth = plugin->smooth;
+
+ /* Output (pointer to float value) */
+ float* output = plugin->output;
+
+ /* Instance data */
+ float nyquist = plugin->nyquist;
+ float inv_nyquist = plugin->inv_nyquist;
+ float phase = plugin->phase;
+ float value1 = plugin->value1;
+ float value2 = plugin->value2;
+
+ float phase_scale = f_clip(frequency, 0.0f, nyquist) * inv_nyquist;
+ float smth;
+ float interval;
+ float result;
+
+ for (uint32_t s = 0; s < sample_count; ++s) {
+ smth = f_clip(smooth[s], 0.0f, 1.0f);
+ interval = (1.0f - smth) * 0.5f;
+
+ if (phase < interval) {
+ result = 1.0f;
+ } else if (phase > (1.0f - interval)) {
+ result = -1.0f;
+ } else if (interval > 0.0f) {
+ result = COSF((phase - interval) / smth * M_PI);
+ } else {
+ result = COSF(phase * M_PI);
+ }
+
+ result *= (value2 - value1) * 0.5f;
+ result -= (value2 + value1) * 0.5f;
+
+ output[s] = result;
+
+ phase += phase_scale;
+ if (phase > 1.0f) {
+ phase -= 1.0f;
+ value1 = value2;
+ value2 = (float)rand() * inv_rand_max - 1.0f;
+ }
+ }
+
+ plugin->phase = phase;
+ plugin->value1 = value1;
+ plugin->value2 = value2;
+}
+
+static void
+runRandom_fcsc_oa(LV2_Handle instance,
+ uint32_t sample_count)
+{
+ Random* plugin = (Random*)instance;
+
+ /* Frequency (Hz) (float value) */
+ float frequency = *(plugin->frequency);
+
+ /* Wave smoothness (float value) */
+ float smooth = f_clip(*(plugin->smooth), 0.0f, 1.0f);
+
+ /* Output (array of floats of length sample_count) */
+ float* output = plugin->output;
+
+ /* Instance data */
+ float nyquist = plugin->nyquist;
+ float inv_nyquist = plugin->inv_nyquist;
+ float phase = plugin->phase;
+ float value1 = plugin->value1;
+ float value2 = plugin->value2;
+
+ float phase_scale = f_clip(frequency, 0.0f, nyquist) * inv_nyquist;
+ float interval = (1.0f - smooth) * 0.5f;
+ float result;
+
+ for (uint32_t s = 0; s < sample_count; ++s) {
+ if (phase < interval) {
+ result = 1.0f;
+ } else if (phase > (1.0f - interval)) {
+ result = -1.0f;
+ } else if (interval > 0.0f) {
+ result = COSF((phase - interval) / smooth * M_PI);
+ } else {
+ result = COSF(phase * M_PI);
+ }
+
+ result *= (value2 - value1) * 0.5f;
+ result -= (value2 + value1) * 0.5f;
+
+ output[s] = result;
+
+ phase += phase_scale;
+ if (phase > 1.0f) {
+ phase -= 1.0f;
+ value1 = value2;
+ value2 = (float)rand() * inv_rand_max - 1.0f;
+ }
+ }
+
+ plugin->phase = phase;
+ plugin->value1 = value1;
+ plugin->value2 = value2;
+}
+
+static const LV2_Descriptor descriptor = {
+ "http://drobilla.net/plugins/blip/random",
+ instantiate,
+ connect_port,
+ activate,
+ runRandom_fcsc_oa,
+ NULL,
+ cleanup,
+ NULL,
+};
+
+LV2_SYMBOL_EXPORT const LV2_Descriptor*
+lv2_descriptor(uint32_t index)
+{
+ switch (index) {
+ case 0: return &descriptor;
+ default: return NULL;
+ }
+}