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-rw-r--r--plugins/eg-metro.lv2/metro.c347
1 files changed, 0 insertions, 347 deletions
diff --git a/plugins/eg-metro.lv2/metro.c b/plugins/eg-metro.lv2/metro.c
deleted file mode 100644
index 97821a1..0000000
--- a/plugins/eg-metro.lv2/metro.c
+++ /dev/null
@@ -1,347 +0,0 @@
-/*
- LV2 Metronome Example Plugin
- Copyright 2012 David Robillard <d@drobilla.net>
-
- Permission to use, copy, modify, and/or distribute this software for any
- purpose with or without fee is hereby granted, provided that the above
- copyright notice and this permission notice appear in all copies.
-
- THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
- WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
- MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
- ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
- WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
- ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
- OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
-*/
-
-#include <math.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#ifndef __cplusplus
-# include <stdbool.h>
-#endif
-
-#include "lv2/lv2plug.in/ns/ext/atom/atom.h"
-#include "lv2/lv2plug.in/ns/ext/atom/util.h"
-#include "lv2/lv2plug.in/ns/ext/time/time.h"
-#include "lv2/lv2plug.in/ns/ext/urid/urid.h"
-#include "lv2/lv2plug.in/ns/lv2core/lv2.h"
-
-#ifndef M_PI
-# define M_PI 3.14159265
-#endif
-
-#define EG_METRO_URI "http://lv2plug.in/plugins/eg-metro"
-
-typedef struct {
- LV2_URID atom_Blank;
- LV2_URID atom_Float;
- LV2_URID atom_Path;
- LV2_URID atom_Resource;
- LV2_URID atom_Sequence;
- LV2_URID time_Position;
- LV2_URID time_barBeat;
- LV2_URID time_beatsPerMinute;
- LV2_URID time_speed;
-} MetroURIs;
-
-static const double attack_s = 0.005;
-static const double decay_s = 0.075;
-
-enum {
- METRO_CONTROL = 0,
- METRO_NOTIFY = 1,
- METRO_OUT = 2
-};
-
-typedef enum {
- STATE_ATTACK,
- STATE_DECAY,
- STATE_OFF
-} State;
-
-typedef struct {
- /* Features */
- LV2_URID_Map* map;
-
- /* URIs */
- MetroURIs uris;
-
- /* Ports */
- struct {
- LV2_Atom_Sequence* control;
- LV2_Atom_Sequence* notify;
- float* output;
- } ports;
-
- /** The rate, bpm, and speed are the basic information sent by the host. */
- double rate;
- float bpm;
- float speed;
-
- /** To keep track of when to play the next click, we need to keep track of
- a few pieces of information: */
-
- /** - The frames since the start of the last click is stored */
- uint32_t elapsed_len;
-
- /** - The current play offset in the wave */
- uint32_t wave_offset;
-
- /** - The current play state (attack, decay, or off) */
- State state;
-
- /** The wave to play is a simple sine wave generated at instantiation time
- based on the sample rate. The length in frames is stored in order to
- continuously play the wave in a cycle to avoid discontinuity clicks. */
- float* wave;
- uint32_t wave_len;
-
- /** The continuously playing sine wave is enveloped to provide an actual
- metronome tick. This plugin uses a simple AD envelope with fixed
- parameters. A more sophisticated implementation might use a more
- advanced envelope and allow the user to modify these parameters. */
- uint32_t attack_len;
- uint32_t decay_len;
-} Metro;
-
-static void
-connect_port(LV2_Handle instance,
- uint32_t port,
- void* data)
-{
- Metro* self = (Metro*)instance;
-
- switch (port) {
- case METRO_CONTROL:
- self->ports.control = (LV2_Atom_Sequence*)data;
- break;
- case METRO_NOTIFY:
- self->ports.notify = (LV2_Atom_Sequence*)data;
- break;
- case METRO_OUT:
- self->ports.output = (float*)data;
- break;
- default:
- break;
- }
-}
-
-static void
-activate(LV2_Handle instance)
-{
- Metro* self = (Metro*)instance;
-
- self->elapsed_len = 0;
- self->wave_offset = 0;
- self->state = STATE_OFF;
-}
-
-static LV2_Handle
-instantiate(const LV2_Descriptor* descriptor,
- double rate,
- const char* path,
- const LV2_Feature* const* features)
-{
- Metro* self = (Metro*)calloc(1, sizeof(Metro));
- if (!self) {
- return NULL;
- }
-
- /** Scan host features for URID map */
- LV2_URID_Map* map = NULL;
- for (int i = 0; features[i]; ++i) {
- if (!strcmp(features[i]->URI, LV2_URID_URI "#map")) {
- map = (LV2_URID_Map*)features[i]->data;
- }
- }
- if (!map) {
- fprintf(stderr, "Host does not support urid:map.\n");
- free(self);
- return NULL;
- }
-
- /** Map URIS */
- MetroURIs* const uris = &self->uris;
- self->map = map;
- uris->atom_Blank = map->map(map->handle, LV2_ATOM__Blank);
- uris->atom_Float = map->map(map->handle, LV2_ATOM__Float);
- uris->atom_Path = map->map(map->handle, LV2_ATOM__Path);
- uris->atom_Resource = map->map(map->handle, LV2_ATOM__Resource);
- uris->atom_Sequence = map->map(map->handle, LV2_ATOM__Sequence);
- uris->time_Position = map->map(map->handle, LV2_TIME__Position);
- uris->time_barBeat = map->map(map->handle, LV2_TIME__barBeat);
- uris->time_beatsPerMinute = map->map(map->handle, LV2_TIME__beatsPerMinute);
- uris->time_speed = map->map(map->handle, LV2_TIME__speed);
-
- /** Initialise fields */
- self->rate = rate;
- self->bpm = 120.0f;
- self->attack_len = attack_s * rate;
- self->decay_len = decay_s * rate;
- self->state = STATE_OFF;
-
- /** Generate one cycle of a sine wave at the desired frequency. */
- const double freq = 440.0 * 2.0;
- const double amp = 0.5;
- self->wave_len = rate / freq;
- self->wave = (float*)malloc(self->wave_len * sizeof(float));
- for (uint32_t i = 0; i < self->wave_len; ++i) {
- self->wave[i] = sin(i * 2 * M_PI * freq / rate) * amp;
- }
-
- return (LV2_Handle)self;
-}
-
-static void
-cleanup(LV2_Handle instance)
-{
- free(instance);
-}
-
-static void
-play(Metro* self, uint32_t begin, uint32_t end)
-{
- float* const output = self->ports.output;
- const uint32_t frames_per_beat = 60.0f / self->bpm * self->rate;
-
- if (self->speed == 0.0f) {
- memset(output, 0, (end - begin) * sizeof(float));
- return;
- }
-
- for (uint32_t i = begin; i < end; ++i) {
- switch (self->state) {
- case STATE_ATTACK:
- /** Amplitude increases from 0..1 until attack_len */
- output[i] = self->wave[self->wave_offset] *
- self->elapsed_len / (float)self->attack_len;
- if (self->elapsed_len >= self->attack_len) {
- self->state = STATE_DECAY;
- }
- break;
- case STATE_DECAY:
- /** Amplitude decreases from 1..0 until attack_len + decay_len */
- output[i] = 0.0f;
- output[i] = self->wave[self->wave_offset] *
- (1 - ((self->elapsed_len - self->attack_len) /
- (float)self->decay_len));
- if (self->elapsed_len >= self->attack_len + self->decay_len) {
- self->state = STATE_OFF;
- }
- break;
- case STATE_OFF:
- output[i] = 0.0f;
- }
-
- /** We continuously play the sine wave regardless of envelope */
- self->wave_offset = (self->wave_offset + 1) % self->wave_len;
-
- /** Update elapsed time and start attack if necessary */
- if (++self->elapsed_len == frames_per_beat) {
- self->state = STATE_ATTACK;
- self->elapsed_len = 0;
- }
- }
-}
-
-static void
-update_position(Metro* self, const LV2_Atom_Object* obj)
-{
- const MetroURIs* uris = &self->uris;
-
- /** Received new transport position/speed */
- LV2_Atom *beat = NULL, *bpm = NULL, *speed = NULL;
- lv2_atom_object_get(obj,
- uris->time_barBeat, &beat,
- uris->time_beatsPerMinute, &bpm,
- uris->time_speed, &speed,
- NULL);
- if (bpm && bpm->type == uris->atom_Float) {
- /** Tempo changed, update BPM */
- self->bpm = ((LV2_Atom_Float*)bpm)->body;
- }
- if (speed && speed->type == uris->atom_Float) {
- /** Speed changed, e.g. 0 (stop) to 1 (play) */
- self->speed = ((LV2_Atom_Float*)speed)->body;
- }
- if (beat && beat->type == uris->atom_Float) {
- /** Received a beat position, synchronise.
- This is a simple hard sync that may cause clicks.
- A real plugin would do something more graceful.
- */
- const float frames_per_beat = 60.0f / self->bpm * self->rate;
- const float bar_beats = ((LV2_Atom_Float*)beat)->body;
- const float beat_beats = bar_beats - floorf(bar_beats);
- self->elapsed_len = beat_beats * frames_per_beat;
- if (self->elapsed_len < self->attack_len) {
- self->state = STATE_ATTACK;
- } else if (self->elapsed_len < self->attack_len + self->decay_len) {
- self->state = STATE_DECAY;
- } else {
- self->state = STATE_OFF;
- }
- }
-}
-
-static void
-run(LV2_Handle instance, uint32_t sample_count)
-{
- Metro* self = (Metro*)instance;
- const MetroURIs* uris = &self->uris;
-
- /** Empty notify output for now */
- LV2_Atom_Sequence* notify = self->ports.notify;
- notify->atom.type = self->uris.atom_Sequence;
- notify->atom.size = sizeof(LV2_Atom_Sequence_Body);
- notify->body.unit = notify->body.pad = 0;
-
- /** Work forwards in time frame by frame, handling events as we go */
- const LV2_Atom_Sequence* in = self->ports.control;
- uint32_t last_t = 0;
- for (LV2_Atom_Event* ev = lv2_atom_sequence_begin(&in->body);
- !lv2_atom_sequence_is_end(&in->body, in->atom.size, ev);
- ev = lv2_atom_sequence_next(ev)) {
-
- /** Play the click for the time slice from last_t until now */
- play(self, last_t, ev->time.frames);
-
- if (ev->body.type == uris->atom_Blank) {
- const LV2_Atom_Object* obj = (LV2_Atom_Object*)&ev->body;
- if (obj->body.otype == uris->time_Position) {
- /** Received position information, update */
- update_position(self, obj);
- }
- }
-
- /** Update time for next iteration and move to next event*/
- last_t = ev->time.frames;
- }
-
- /** Play for remainder of cycle */
- play(self, last_t, sample_count);
-}
-
-static const LV2_Descriptor descriptor = {
- EG_METRO_URI,
- instantiate,
- connect_port,
- activate,
- run,
- NULL, // deactivate,
- cleanup,
- NULL, // extension_data
-};
-
-LV2_SYMBOL_EXPORT const LV2_Descriptor*
-lv2_descriptor(uint32_t index)
-{
- switch (index) {
- case 0:
- return &descriptor;
- default:
- return NULL;
- }
-}
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