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-rw-r--r--plugins/eg02-midigate.lv2/midigate.c227
1 files changed, 0 insertions, 227 deletions
diff --git a/plugins/eg02-midigate.lv2/midigate.c b/plugins/eg02-midigate.lv2/midigate.c
deleted file mode 100644
index 8d2bd74..0000000
--- a/plugins/eg02-midigate.lv2/midigate.c
+++ /dev/null
@@ -1,227 +0,0 @@
-/*
- Copyright 2013 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 <stdio.h>
-
-#include <math.h>
-#include <stdlib.h>
-
-#include "lv2/lv2plug.in/ns/ext/atom/atom.h"
-#include "lv2/lv2plug.in/ns/ext/atom/util.h"
-#include "lv2/lv2plug.in/ns/ext/midi/midi.h"
-#include "lv2/lv2plug.in/ns/ext/urid/urid.h"
-#include "lv2/lv2plug.in/ns/lv2core/lv2.h"
-
-#define MIDIGATE_URI "http://lv2plug.in/plugins/eg-midigate"
-
-typedef enum {
- MIDIGATE_CONTROL = 0,
- MIDIGATE_IN = 1,
- MIDIGATE_OUT = 2
-} PortIndex;
-
-typedef struct {
- // Port buffers
- const LV2_Atom_Sequence* control;
- const float* in;
- float* out;
-
- // Features
- LV2_URID_Map* map;
-
- struct {
- LV2_URID midi_MidiEvent;
- } uris;
-
- unsigned n_active_notes;
- unsigned program; // 0 = normal, 1 = inverted
-} Midigate;
-
-static LV2_Handle
-instantiate(const LV2_Descriptor* descriptor,
- double rate,
- const char* bundle_path,
- const LV2_Feature* const* features)
-{
- /** Scan features array for the URID feature we need. */
- LV2_URID_Map* map = NULL;
- for (int i = 0; features[i]; ++i) {
- if (!strcmp(features[i]->URI, LV2_URID__map)) {
- map = (LV2_URID_Map*)features[i]->data;
- break;
- }
- }
- if (!map) {
- /**
- No URID feature given. This is a host bug since we require this
- feature, but should be handled gracefully anyway.
- */
- return NULL;
- }
-
- Midigate* self = (Midigate*)calloc(1, sizeof(Midigate));
- self->map = map;
- self->uris.midi_MidiEvent = map->map(map->handle, LV2_MIDI__MidiEvent);
-
- return (LV2_Handle)self;
-}
-
-static void
-connect_port(LV2_Handle instance,
- uint32_t port,
- void* data)
-{
- Midigate* self = (Midigate*)instance;
-
- switch ((PortIndex)port) {
- case MIDIGATE_CONTROL:
- self->control = (const LV2_Atom_Sequence*)data;
- break;
- case MIDIGATE_IN:
- self->in = (const float*)data;
- break;
- case MIDIGATE_OUT:
- self->out = (float*)data;
- break;
- }
-}
-
-static void
-activate(LV2_Handle instance)
-{
- Midigate* self = (Midigate*)instance;
- self->n_active_notes = 0;
- self->program = 0;
-}
-
-/**
- A function to write a chunk of output, to be called from run(). If the gate
- is high, then the input will be passed through for this chunk, otherwise
- silence is written.
-*/
-static void
-write_output(Midigate* self, uint32_t offset, uint32_t len)
-{
- const bool active = (self->program == 0)
- ? (self->n_active_notes > 0)
- : (self->n_active_notes == 0);
- if (active) {
- memcpy(self->out + offset, self->in + offset, len * sizeof(float));
- } else {
- memset(self->out + offset, 0, len * sizeof(float));
- }
-}
-
-/**
- This plugin works through the cycle in chunks starting at offset zero. The
- +offset+ represents the current time within this this cycle, so
- the output from 0 to +offset+ has already been written.
-
- MIDI events are read in a loop. In each iteration, the number of active
- notes (on note on and note off) or the program (on program change) is
- updated, then the output is written up until the current event time. Then
- +offset+ is updated and the next event is processed. After the loop the
- final chunk from the last event to the end of the cycle is emitted.
-
- There is currently no standard way to describe MIDI programs in LV2, so the
- host has no way of knowing that these programs exist and should be presented
- to the user. A future version of LV2 will address this shortcoming.
-
- This pattern of iterating over input events and writing output along the way
- is a common idiom for writing sample accurate output based on event input.
-
- Note that this simple example simply writes input or zero for each sample
- based on the gate. A serious implementation would need to envelope the
- transition to avoid aliasing.
-*/
-static void
-run(LV2_Handle instance, uint32_t sample_count)
-{
- Midigate* self = (Midigate*)instance;
- uint32_t offset = 0;
-
- LV2_ATOM_SEQUENCE_FOREACH(self->control, ev) {
- if (ev->body.type == self->uris.midi_MidiEvent) {
- const uint8_t* const msg = (const uint8_t*)(ev + 1);
- switch (lv2_midi_message_type(msg)) {
- case LV2_MIDI_MSG_NOTE_ON:
- ++self->n_active_notes;
- break;
- case LV2_MIDI_MSG_NOTE_OFF:
- --self->n_active_notes;
- break;
- case LV2_MIDI_MSG_PGM_CHANGE:
- if (msg[1] == 0 || msg[1] == 1) {
- self->program = msg[1];
- }
- break;
- default: break;
- }
- }
-
- write_output(self, offset, ev->time.frames - offset);
- offset = (uint32_t)ev->time.frames;
- }
-
- write_output(self, offset, sample_count - offset);
-}
-
-/**
- We have no resources to free on deactivation.
- Note that the next call to activate will re-initialise the state, namely
- self->n_active_notes, so there is no need to do so here.
-*/
-static void
-deactivate(LV2_Handle instance)
-{}
-
-static void
-cleanup(LV2_Handle instance)
-{
- free(instance);
-}
-
-/**
- This plugin also has no extension data to return.
-*/
-static const void*
-extension_data(const char* uri)
-{
- return NULL;
-}
-
-static const LV2_Descriptor descriptor = {
- MIDIGATE_URI,
- instantiate,
- connect_port,
- activate,
- run,
- deactivate,
- cleanup,
- extension_data
-};
-
-LV2_SYMBOL_EXPORT
-const LV2_Descriptor*
-lv2_descriptor(uint32_t index)
-{
- switch (index) {
- case 0:
- return &descriptor;
- default:
- return NULL;
- }
-}