jake/soundThing
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Initial commit of project.

Browse Source
This commit is contained in:
Anachronaut
2026-03-13 15:09:17 -04:00
commit 48ee8c2c75
7 changed files with 485 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

111
source/midi.c Normal file
View File

@@ -0,0 +1,111 @@
#include "midi.h"
#include <stdio.h>
#include <poll.h>
#include <stdatomic.h>
#include <alloca.h>
extern atomic_int gRunning;
int midiInit(MidiState *m, Synth *synth)
{
if (snd_seq_open(&m->seq, "default", SND_SEQ_OPEN_INPUT | SND_SEQ_NONBLOCK, 0) < 0) {
fprintf(stderr, "Failed to open ALSA sequencer\n");
return 0;
}
snd_seq_nonblock(m->seq, 1);
snd_seq_set_client_name(m->seq, "soundThing");
m->client = snd_seq_client_id(m->seq);
m->port = snd_seq_create_simple_port(m->seq, "MIDI In",
SND_SEQ_PORT_CAP_WRITE | SND_SEQ_PORT_CAP_SUBS_WRITE,
SND_SEQ_PORT_TYPE_APPLICATION);
m->synth = synth;
return 1;
}
void midiListInputs(MidiState *m)
{
snd_seq_client_info_t *cinfo;
snd_seq_port_info_t *pinfo;
snd_seq_client_info_alloca(&cinfo);
snd_seq_port_info_alloca(&pinfo);
printf("\nAvailable MIDI inputs:\n");
snd_seq_client_info_set_client(cinfo, -1);
while (snd_seq_query_next_client(m->seq, cinfo) >= 0) {
int client = snd_seq_client_info_get_client(cinfo);
if (client == m->client) continue;
snd_seq_port_info_set_client(pinfo, client);
snd_seq_port_info_set_port(pinfo, -1);
while (snd_seq_query_next_port(m->seq, pinfo) >= 0) {
unsigned int caps = snd_seq_port_info_get_capability(pinfo);
if (caps & SND_SEQ_PORT_CAP_READ && caps & SND_SEQ_PORT_CAP_SUBS_READ) {
printf(" [%d:%d] %s — %s\n",
client,
snd_seq_port_info_get_port(pinfo),
snd_seq_client_info_get_name(cinfo),
snd_seq_port_info_get_name(pinfo));
}
}
}
}
void midiConnect(MidiState *m, int srcClient, int srcPort)
{
snd_seq_port_subscribe_t *sub;
snd_seq_addr_t sender, dest;
sender.client = srcClient;
sender.port = srcPort;
dest.client = m->client;
dest.port = m->port;
snd_seq_port_subscribe_alloca(&sub);
snd_seq_port_subscribe_set_sender(sub, &sender);
snd_seq_port_subscribe_set_dest(sub, &dest);
snd_seq_subscribe_port(m->seq, sub);
printf("Connected [%d:%d] to Cricket\n", srcClient, srcPort);
}
void midiClose(MidiState *m)
{
snd_seq_close(m->seq);
}
void *midiThread(void *arg)
{
MidiState *m = (MidiState *)arg;
struct pollfd pfd;
snd_seq_poll_descriptors(m->seq, &pfd, 1, POLLIN);
while (gRunning) {
int ready = poll(&pfd, 1, 50);
if (ready <= 0) continue;
snd_seq_event_t *ev = NULL;
while (snd_seq_event_input(m->seq, &ev) >= 0 && ev) {
switch (ev->type) {
case SND_SEQ_EVENT_NOTEON:
if (ev->data.note.velocity == 0)
synthNoteOff(m->synth, ev->data.note.note);
else
synthNoteOn(m->synth, ev->data.note.note);
break;
case SND_SEQ_EVENT_NOTEOFF:
synthNoteOff(m->synth, ev->data.note.note);
break;
case SND_SEQ_EVENT_CONTROLLER:
if (ev->data.control.param == 70)
m->synth->waveform = ev->data.control.value % WAVE_COUNT;
break;
case SND_SEQ_EVENT_PITCHBEND:
m->synth->pitchBend = ev->data.control.value / 8191.0f;
break;
}
snd_seq_free_event(ev);
ev = NULL;
}
}
return NULL;
}

94
source/soundThing.c Normal file
View File

@@ -0,0 +1,94 @@
#define _POSIX_C_SOURCE 200809L
#include <stdio.h>
#include <stdatomic.h>
#include <pthread.h>
#include <alloca.h>
#include <alsa/asoundlib.h>
#include "raylib.h"
#include "synth.h"
#include "midi.h"
atomic_int gRunning = 1;
static Synth gSynth = {0};
static MidiState gMidi = {0};
static void AudioOutputCallback(void *buffer, unsigned int frames)
{
synthFillBuffer(&gSynth, (int16_t *)buffer, (int)frames);
}
static void drawWaveform(Waveform w, float dutyCycle, int x, int y, int width, int height)
{
int steps = width;
for (int i = 0; i < steps - 1; i++) {
float phase0 = (float)i / steps;
float phase1 = (float)(i + 1) / steps;
float s0 = waveformSample(w, phase0, dutyCycle);
float s1 = waveformSample(w, phase1, dutyCycle);
int cx = x + i;
int cy = y + (int)((1.0f - (s0 * 0.5f + 0.5f)) * height);
int nx = x + i + 1;
int ny = y + (int)((1.0f - (s1 * 0.5f + 0.5f)) * height);
DrawLine(cx, cy, nx, ny, GREEN);
}
DrawRectangleLines(x, y, width, height, DARKGRAY);
}
int main(void)
{
const int sampleRate = 48000;
if (!midiInit(&gMidi, &gSynth)) return 1;
midiListInputs(&gMidi);
int srcClient, srcPort;
printf("\nEnter client and port to connect (e.g. '20 0'), or -1 -1 to skip: ");
if (scanf("%d %d", &srcClient, &srcPort) == 2 && srcClient != -1)
midiConnect(&gMidi, srcClient, srcPort);
pthread_t midiTid;
pthread_create(&midiTid, NULL, midiThread, &gMidi);
synthInit(&gSynth, (float)sampleRate);
InitWindow(800, 450, "SoundThing");
InitAudioDevice();
SetAudioStreamBufferSizeDefault(1024);
AudioStream stream = LoadAudioStream(sampleRate, 16, 1);
SetAudioStreamCallback(stream, AudioOutputCallback);
PlayAudioStream(stream);
SetTargetFPS(120);
while (!WindowShouldClose()) {
if (IsKeyPressed(KEY_UP))
gSynth.waveform = (gSynth.waveform + 1) % WAVE_COUNT;
if (IsKeyPressed(KEY_DOWN))
gSynth.waveform = (gSynth.waveform + WAVE_COUNT - 1) % WAVE_COUNT;
BeginDrawing();
ClearBackground(BLACK);
drawWaveform(gSynth.waveform, gSynth.dutyCycle, 20, 120, 400, 150);
DrawText("SoundThing", 20, 20, 24, RAYWHITE);
DrawText(TextFormat("Waveform: %s (UP/DOWN to change)", waveformName(gSynth.waveform)),
20, 55, 20, RAYWHITE);
DrawText(TextFormat("MIDI: client %d port %d", gMidi.client, gMidi.port),
20, 90, 20, GRAY);
EndDrawing();
}
gRunning = 0;
StopAudioStream(stream);
UnloadAudioStream(stream);
CloseAudioDevice();
CloseWindow();
pthread_join(midiTid, NULL);
midiClose(&gMidi);
return 0;
}

139
source/synth.c Normal file
View File

@@ -0,0 +1,139 @@
#include "synth.h"
#include <math.h>
#include <stdlib.h>
#include <stdint.h>
#ifndef M_PI
#define M_PI 3.14159265358979323846
#endif
void synthInit(Synth *s, float sampleRate)
{
s->sampleRate = sampleRate;
s->attackSec = 0.005f;
s->releaseSec = 0.050f;
s->dutyCycle = 0.5f;
s->waveform = WAVE_SINE;
s->lastStolenVoice = 0;
for (int i = 0; i < VOICE_COUNT; i++) {
s->voices[i].phase = 0.0f;
s->voices[i].freqHz = 440.0f;
s->voices[i].amp = 0.0f;
s->voices[i].targetAmp = 0.0f;
s->voices[i].active = 0;
s->voices[i].midiNote = -1;
s->pitchBend = 0.0f;
s->pitchBendRange = 2.0f;
}
}
float waveformSample(Waveform w, float phase, float dutyCycle)
{
switch (w) {
case WAVE_SINE:
return sinf(2.0f * (float)M_PI * phase);
case WAVE_TRIANGLE:
return (phase < 0.5f)
? ( 4.0f * phase - 1.0f)
: (-4.0f * phase + 3.0f);
case WAVE_SAW:
return 2.0f * phase - 1.0f;
case WAVE_RAMP:
return 1.0f - 2.0f * phase;
case WAVE_PULSE:
return (phase < dutyCycle) ? 1.0f : -1.0f;
case WAVE_NOISE:
return ((float)rand() / (float)RAND_MAX) * 2.0f - 1.0f;
default:
return 0.0f;
}
}
const char *waveformName(Waveform w)
{
switch (w) {
case WAVE_SINE: return "Sine";
case WAVE_TRIANGLE: return "Triangle";
case WAVE_SAW: return "Saw";
case WAVE_RAMP: return "Ramp";
case WAVE_PULSE: return "Pulse";
case WAVE_NOISE: return "Noise";
default: return "???";
}
}
void synthNoteOn(Synth *s, int midiNote)
{
float hz = 440.0f * powf(2.0f, (midiNote - 69) / 12.0f);
for (int i = 0; i < VOICE_COUNT; i++) {
if (!s->voices[i].active) {
s->voices[i].freqHz = hz;
s->voices[i].midiNote = midiNote;
s->voices[i].targetAmp = 1.0f;
s->voices[i].active = 1;
return;
}
}
// No free voice — steal round-robin
int i = s->lastStolenVoice % VOICE_COUNT;
s->lastStolenVoice++;
s->voices[i].freqHz = hz;
s->voices[i].midiNote = midiNote;
s->voices[i].targetAmp = 1.0f;
s->voices[i].phase = 0.0f;
s->voices[i].active = 1;
}
void synthNoteOff(Synth *s, int midiNote)
{
for (int i = 0; i < VOICE_COUNT; i++) {
if (s->voices[i].active && s->voices[i].midiNote == midiNote)
s->voices[i].targetAmp = 0.0f;
}
}
void synthFillBuffer(Synth *s, int16_t *out, int frames)
{
const float sr = s->sampleRate;
const float attackInc = (s->attackSec <= 0.0f) ? 1.0f : (1.0f / (s->attackSec * sr));
const float releaseInc = (s->releaseSec <= 0.0f) ? 1.0f : (1.0f / (s->releaseSec * sr));
for (int i = 0; i < frames; i++) {
float mix = 0.0f;
for (int v = 0; v < VOICE_COUNT; v++) {
Voice *vv = &s->voices[v];
if (!vv->active) continue;
if (vv->targetAmp > vv->amp) {
vv->amp += attackInc;
if (vv->amp > vv->targetAmp) vv->amp = vv->targetAmp;
} else if (vv->targetAmp < vv->amp) {
vv->amp -= releaseInc;
if (vv->amp < vv->targetAmp) vv->amp = vv->targetAmp;
}
if (vv->amp <= 0.0f && vv->targetAmp == 0.0f) {
vv->active = 0;
continue;
}
//vv->phase += vv->freqHz / sr;
float bendMultiplier = powf(2.0f, (s->pitchBend * s->pitchBendRange) / 12.0f);
vv->phase += (vv->freqHz * bendMultiplier) / sr;
if (vv->phase >= 1.0f) vv->phase -= 1.0f;
mix += waveformSample(s->waveform, vv->phase, s->dutyCycle) * vv->amp;
}
mix *= (0.2f / VOICE_COUNT) * 4.0f;
int32_t sample = (int32_t)lrintf(mix * 32767.0f);
if (sample > 32767) sample = 32767;
if (sample < -32768) sample = -32768;
out[i] = (int16_t)sample;
}
}