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-rw-r--r--src/adenv_lvl.c299
1 files changed, 299 insertions, 0 deletions
diff --git a/src/adenv_lvl.c b/src/adenv_lvl.c
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+++ b/src/adenv_lvl.c
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+/*
+ adenv.c - A LV2 plugin to generate percussive (i.e no sustain time), linear AD envelopes.
+ This one takes in levels to make filter sweeps/etc easier.
+
+ Copyright 2005 Loki Davison
+ based of DADSR by Mike Rawes
+
+ This program 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 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 General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
+*/
+
+#define _XOPEN_SOURCE 600 /* strdup */
+#include <stdlib.h>
+#include <lv2/lv2plug.in/ns/lv2core/lv2.h>
+#include <stdio.h>
+#include <math.h>
+
+#define ADENVLVL_BASE_ID 2662
+#define ADENVLVL_VARIANT_COUNT 1
+
+#define ADENVLVL_GATE 0
+#define ADENVLVL_TRIGGER 1
+#define ADENVLVL_START_LEVEL 2
+#define ADENVLVL_ATTACK_LEVEL 3
+#define ADENVLVL_DECAY_LEVEL 4
+#define ADENVLVL_ATTACK 5
+#define ADENVLVL_DECAY 6
+#define ADENVLVL_OUTPUT 7
+#define ADENVLVL_RESET 8
+
+typedef enum {
+ IDLE,
+ ATTACK,
+ DECAY,
+} ADENVLVLState;
+
+typedef struct {
+ float *gate;
+ float *trigger;
+ float *attack;
+ float *reset;
+ float *decay;
+ float *start_level;
+ float *attack_level;
+ float *decay_level;
+ float *output;
+ float srate;
+ float inv_srate;
+ float last_gate;
+ float last_trigger;
+ float last_reset;
+ float level;
+ ADENVLVLState state;
+ unsigned long samples;
+} Dahdsr;
+
+static void
+cleanup(LV2_Handle instance)
+{
+ free(instance);
+}
+
+static void
+connect_port(LV2_Handle instance,
+ uint32_t port, void * data)
+{
+ Dahdsr *plugin = (Dahdsr *) instance;
+
+ switch (port) {
+ case ADENVLVL_GATE:
+ plugin->gate = (float*)data;
+ break;
+ case ADENVLVL_TRIGGER:
+ plugin->trigger = (float*)data;
+ break;
+ case ADENVLVL_START_LEVEL:
+ plugin->start_level = (float*)data;
+ break;
+ case ADENVLVL_ATTACK_LEVEL:
+ plugin->attack_level = (float*)data;
+ break;
+ case ADENVLVL_DECAY_LEVEL:
+ plugin->decay_level = (float*)data;
+ break;
+ case ADENVLVL_ATTACK:
+ plugin->attack = (float*)data;
+ break;
+ case ADENVLVL_DECAY:
+ plugin->decay = (float*)data;
+ break;
+ case ADENVLVL_RESET:
+ plugin->reset = (float*)data;
+ break;
+ case ADENVLVL_OUTPUT:
+ plugin->output = (float*)data;
+ break;
+ }
+}
+
+static LV2_Handle
+instantiate(const LV2_Descriptor* descriptor,
+ double sample_rate,
+ const char* bundle_path,
+ const LV2_Feature* const* features)
+{
+ Dahdsr *plugin = (Dahdsr *) malloc(sizeof(Dahdsr));
+
+ plugin->srate = (float) sample_rate;
+ plugin->inv_srate = 1.0f / plugin->srate;
+
+ return (LV2_Handle) plugin;
+}
+
+static void
+activate(LV2_Handle instance)
+{
+ Dahdsr *plugin = (Dahdsr *) instance;
+
+ plugin->last_gate = 0.0f;
+ plugin->last_trigger = 0.0f;
+ plugin->last_reset = 0.0f;
+ plugin->level = 0.0f;
+ plugin->state = IDLE;
+ plugin->samples = 0;
+}
+
+static void
+run(LV2_Handle instance, uint32_t sample_count)
+{
+ Dahdsr *plugin = (Dahdsr *) instance;
+
+ /* Gate */
+ float *gate = plugin->gate;
+
+ /* Trigger */
+ float *trigger = plugin->trigger;
+
+ /* Reset */
+ float *reset = plugin->reset;
+
+ /* Start Level */
+ float start_level = *(plugin->start_level);
+
+ /* Attack Level */
+ float attack_level = *(plugin->attack_level);
+
+ /* Decay Level */
+ float decay_level = *(plugin->decay_level);
+
+ /* Attack Time (s) */
+ float attack = *(plugin->attack);
+
+ /* Decay Time (s) */
+ float decay = *(plugin->decay);
+
+ /* Envelope Out */
+ float *output = plugin->output;
+
+ /* Instance Data */
+ float srate = plugin->srate;
+ float inv_srate = plugin->inv_srate;
+ float last_gate = plugin->last_gate;
+ float last_trigger = plugin->last_trigger;
+ float last_reset = plugin->last_reset;
+ float level = plugin->level;
+ ADENVLVLState state = plugin->state;
+ unsigned long samples = plugin->samples;
+
+ float gat, trg, att, dec;
+ float elapsed;
+ unsigned long s;
+
+ /* Convert times into rates */
+ att = attack > 0.0f ? inv_srate / attack : srate;
+ dec = decay > 0.0f ? inv_srate / decay : srate;
+ /* cuse's formula ...
+ * ReleaseCoeff = (ln(EndLevel) - ln(StartLevel)) / (EnvelopeDuration * SampleRate)
+ *
+ * while (currentSample < endSample) Level += Level * ReleaseCoeff;
+ */
+ /* check params don't cause div by zero */
+ if (start_level == 0) {
+ start_level = 0.0000001;
+ }
+ if (attack_level == 0) {
+ attack_level = 0.0000001;
+ }
+ if (decay_level == 0) {
+ decay_level = 0.0000001;
+ }
+ float ReleaseCoeff_att =
+ (log(attack_level) - log(start_level)) / (attack * srate);
+ float ReleaseCoeff_dec =
+ (log(decay_level) - log(attack_level)) / (decay * srate);
+
+ for (s = 0; s < sample_count; s++) {
+ gat = gate[s];
+ trg = trigger[s];
+
+ /* Initialise delay phase if gate is opened and was closed, or
+ we received a trigger */
+ if ((trg > 0.0f && !(last_trigger > 0.0f)) ||
+ (gat > 0.0f && !(last_gate > 0.0f))) {
+ //fprintf(stderr, "triggered in control \n");
+ if (att < srate) {
+ state = ATTACK;
+ }
+ samples = 0;
+ }
+ /* if we got a reset */
+
+ if (reset[s] > 0.0f && !(last_reset > 0.0f)) {
+ level = start_level;
+ /*fprintf(stderr, "got reset start level %f \n", start_level); */
+ }
+
+ /* Calculate level of envelope from current state */
+ switch (state) {
+ case IDLE:
+ /* might need to fix this... */
+ break;
+ case ATTACK:
+ /* fix level adding prob */
+ if (samples == 0) {
+ level = start_level;
+ }
+ samples++;
+ elapsed = (float) samples *att;
+
+ if (elapsed > 1.0f) {
+ state = DECAY;
+ samples = 0;
+ //fprintf(stderr, "finished attack, RC %f, level %f attack_level %f start %f\n", ReleaseCoeff_att, level, attack_level, start_level);
+ } else {
+ level += level * ReleaseCoeff_att;
+ }
+ break;
+ case DECAY:
+ samples++;
+ elapsed = (float) samples *dec;
+
+ if (elapsed > 1.0f) {
+ //fprintf(stderr, "finished decay, RC %f , level %f decay_level %f start %f\n", ReleaseCoeff_dec, level, decay_level, start_level);
+ state = IDLE;
+ samples = 0;
+ } else {
+ level += level * ReleaseCoeff_dec;
+ }
+ break;
+ default:
+ /* Should never happen */
+ fprintf(stderr, "bugger!!!");
+ level = 0.0f;
+ }
+
+ output[s] = level;
+ last_gate = gat;
+ last_trigger = trg;
+ last_reset = reset[s];
+ }
+
+ plugin->last_gate = last_gate;
+ plugin->last_trigger = last_trigger;
+ plugin->last_reset = last_reset;
+ plugin->level = level;
+ plugin->state = state;
+ plugin->samples = samples;
+}
+
+static const LV2_Descriptor descriptor = {
+ "http://drobilla.net/plugins/omins/adenv_lvl",
+ instantiate,
+ connect_port,
+ activate,
+ run,
+ NULL,
+ cleanup,
+ NULL,
+};
+
+LV2_SYMBOL_EXPORT const LV2_Descriptor*
+lv2_descriptor(uint32_t index)
+{
+ switch (index) {
+ case 0: return &descriptor;
+ default: return NULL;
+ }
+}
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