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#include <alsa/asoundlib.h>
#include <pthread.h>
#include <stdio.h>
#include "clay/clay.h"
#define SDL_MAIN_USE_CALLBACKS 1
#include <SDL3/SDL.h>
#include <SDL3/SDL_main.h>
#include <SDL3/SDL_scancode.h>
#include <SDL3/SDL_keycode.h>
#include "sounds.h"
const int SCREEN_FPS = 60;
const int SCREEN_TICKS_PER_FRAME = 1000 / SCREEN_FPS;
typedef struct {
char key;
float freq;
} freq_map;
typedef struct {
SDL_Window *window;
SDL_Renderer *renderer;
bool last_keys[12];
snd_pcm_t *sound_device;
message_queue msg_queue;
pthread_t sound_thread;
} app_state;
int init_sounds(app_state *state) {
int err;
err =
snd_pcm_open(&state->sound_device, "default", SND_PCM_STREAM_PLAYBACK, 0);
if (err < 0) {
printf("error: failed to open device: %s", snd_strerror(err));
return err;
}
err = set_hw_params(state->sound_device);
if (err < 0) {
printf("error: failed to set parameters: %s", snd_strerror(err));
return err;
}
mqueue_init(&state->msg_queue);
sound_thread_meta *sound_thread_params = malloc(sizeof(sound_thread_meta));
sound_thread_params->pcm = state->sound_device;
sound_thread_params->queue = &state->msg_queue;
pthread_t sound_thread;
pthread_create(&sound_thread, NULL, sound_thread_start, sound_thread_params);
state->sound_thread = sound_thread;
synth_message param_message = {
.type = MSG_PARAM_CHANGE,
.param_change =
{
.param_type = PARAM_OSC,
.value = OSC_SQUARE,
},
};
mqueue_push(&state->msg_queue, param_message);
param_message = (synth_message){
.type = MSG_PARAM_CHANGE,
.param_change =
{
.param_type = PARAM_VOLUME,
.value = 1,
},
};
mqueue_push(&state->msg_queue, param_message);
return 0;
}
SDL_AppResult SDL_AppInit(void **appstate, int argc, char **argv) {
app_state *state = malloc(sizeof(app_state));
*appstate = state;
if (!SDL_Init(SDL_INIT_VIDEO)) {
printf("Couldn't initialize SDL: %s", SDL_GetError());
return SDL_APP_FAILURE;
}
if (!SDL_CreateWindowAndRenderer("crynth", 640, 480, 0, &state->window,
&state->renderer)) {
printf("Couldn't create window/renderer: %s", SDL_GetError());
return SDL_APP_FAILURE;
}
if (init_sounds(state) != 0) {
return SDL_APP_FAILURE;
}
return SDL_APP_CONTINUE;
}
SDL_AppResult SDL_AppIterate(void *appstate) {
app_state *state = appstate;
int start_tick = SDL_GetTicks();
const double now = ((double)SDL_GetTicks()) / 1000.0;
const float red = (float)(0.5 + 0.5 * SDL_sin(now));
const float green = (float)(0.5 + 0.5 * SDL_sin(now + SDL_PI_D * 2 / 3));
const float blue = (float)(0.5 + 0.5 * SDL_sin(now + SDL_PI_D * 4 / 3));
SDL_SetRenderDrawColorFloat(state->renderer, red, green, blue, SDL_ALPHA_OPAQUE_FLOAT);
SDL_RenderClear(state->renderer);
SDL_RenderPresent(state->renderer);
int end_tick = SDL_GetTicks();
int frame_ticks = end_tick - start_tick;
if (frame_ticks < SCREEN_TICKS_PER_FRAME) {
SDL_Delay(SCREEN_TICKS_PER_FRAME - frame_ticks);
}
return SDL_APP_CONTINUE;
}
SDL_Keycode keys[12] = {
SDL_SCANCODE_Z, SDL_SCANCODE_S,
SDL_SCANCODE_X, SDL_SCANCODE_D,
SDL_SCANCODE_C,
SDL_SCANCODE_V, SDL_SCANCODE_G,
SDL_SCANCODE_B, SDL_SCANCODE_H,
SDL_SCANCODE_N, SDL_SCANCODE_J,
SDL_SCANCODE_M,
};
SDL_AppResult SDL_AppEvent(void *appstate, SDL_Event *event) {
app_state *state = appstate;
switch (event->type) {
case SDL_EVENT_QUIT: {
return SDL_APP_SUCCESS;
}
case SDL_EVENT_KEY_DOWN: {
for (int i = 0; i < 12; i++) {
if (event->key.scancode == keys[i]) {
if (state->last_keys[i]) {
break;
}
state->last_keys[i] = true;
mqueue_push(&state->msg_queue, (synth_message){
.type = MSG_NOTE_ON,
.note = { .note_id = i },
});
}
}
break;
}
case SDL_EVENT_KEY_UP: {
for (int i = 0; i < 12; i++) {
if (event->key.scancode == keys[i]) {
if (!state->last_keys[i]) {
break;
}
state->last_keys[i] = false;
mqueue_push(&state->msg_queue, (synth_message){
.type = MSG_NOTE_OFF,
.note = { .note_id = i },
});
}
}
break;
}
default: {};
}
return SDL_APP_CONTINUE;
}
void SDL_AppQuit(void *appstate, SDL_AppResult result) {
app_state *state = appstate;
message_queue *queue = &state->msg_queue;
synth_message stop_msg = {.type = MSG_STOP};
mqueue_push(queue, stop_msg);
pthread_join(state->sound_thread, NULL);
check(snd_pcm_close(state->sound_device));
}
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