From 9437c4e52024d7248b64114ec42e779a5d7473d8 Mon Sep 17 00:00:00 2001
From: Bad Diode <bd@badd10de.dev>
Date: Tue, 10 Oct 2023 15:39:47 +0200
Subject: [PATCH] Add sample duration handling

---
 src/devices/audio.c | 21 +++++++++------------
 src/devices/audio.h |  4 ++--
 src/uxn.h           |  2 +-
 src/uxnemu.c        | 22 ++++++++++++++++------
 4 files changed, 28 insertions(+), 21 deletions(-)

diff --git a/src/devices/audio.c b/src/devices/audio.c
index f761854..7696016 100644
--- a/src/devices/audio.c
+++ b/src/devices/audio.c
@@ -2608,23 +2608,20 @@ audio_handler(void *ctx, Uint8 *out_stream, int len) {
 
     for (int n = 0; n < N_CHANNELS; n++) {
         Uint8 device = (3 + n) << 4;
-        // TODO: Make sure this works properly and evals to the audio stack
-        // instead of the regular stack.
-        // Uxn *u = (Uxn *)ctx;
-        // Uint8 *addr = &u->dev[device];
-        // if (channel[n].duration <= 0 && PEEK2(addr)) {
-			// uxn_eval(u, PEEK2(addr));
-        // }
-        // printf("DEVICE: %x\n", device);
-        // printf("ADDR: %x\n", PEEK2(addr));
-        if (channel[n].sample.data != 0) {
-            channel[n].duration -= SOUND_TIMER;
+        Uxn *u = (Uxn *)ctx;
+        Uint8 *addr = &u->dev[device];
+        if (channel[n].duration <= 0 && PEEK2(addr)) {
+			uxn_eval(u, PEEK2(addr));
+            // printf("EVAL: %x\n", device);
+            // printf("ADDR: %x\n", PEEK2(addr));
+            // printf("----\n");
         }
+        channel[n].duration -= SOUND_TIMER;
 
         int x = 0;
         if (channel[n].xfade) {
             float delta = 1.0f / (XFADE_SAMPLES);
-            while (x < XFADE_SAMPLES * 2) {
+            while (x < XFADE_SAMPLES * 2 && x < len / 2) {
                 float alpha = x * delta;
                 float beta = 1.0f - alpha;
                 Sint16 next_a = next_a = next_sample(&channel[n].next_sample);
diff --git a/src/devices/audio.h b/src/devices/audio.h
index 7872715..2ec285a 100644
--- a/src/devices/audio.h
+++ b/src/devices/audio.h
@@ -15,8 +15,8 @@ typedef signed int Sint32;
 #define AUDIO_DEIMASK 0x0014
 #define AUDIO_DEOMASK 0x8000
 
-#define AUDIO_BUFSIZE 256
-#define SAMPLE_FREQUENCY 44100
+#define AUDIO_BUFSIZE 256.0f
+#define SAMPLE_FREQUENCY 44100.0f
 #define POLYPHONY 4
 
 Uint8 audio_get_vu(int instance);
diff --git a/src/uxn.h b/src/uxn.h
index 04f4aa5..6a0dc97 100644
--- a/src/uxn.h
+++ b/src/uxn.h
@@ -29,7 +29,7 @@ typedef struct {
 } Stack;
 
 typedef struct Uxn {
-	Uint8 *ram, dev[0x100];
+	Uint8 *ram, *dev;
 	Stack wst, rst;
 } Uxn;
 
diff --git a/src/uxnemu.c b/src/uxnemu.c
index 26ec193..4fe3551 100644
--- a/src/uxnemu.c
+++ b/src/uxnemu.c
@@ -103,7 +103,6 @@ audio_deo(int instance, Uint8 *d, Uint8 port, Uxn *u)
 		SDL_LockAudioDevice(audio_id);
 		audio_start(instance, d, u);
 		SDL_UnlockAudioDevice(audio_id);
-		SDL_PauseAudioDevice(audio_id, 0);
 	}
 }
 
@@ -251,7 +250,7 @@ emu_redraw(Uxn *u)
 }
 
 static int
-emu_init(void)
+emu_init(Uxn *u)
 {
 	SDL_AudioSpec as;
 	SDL_zero(as);
@@ -260,7 +259,7 @@ emu_init(void)
 	as.channels = 2;
 	as.callback = audio_handler;
 	as.samples = AUDIO_BUFSIZE;
-	as.userdata = NULL;
+	as.userdata = u;
 	if(SDL_Init(SDL_INIT_VIDEO | SDL_INIT_AUDIO | SDL_INIT_JOYSTICK) < 0)
 		return system_error("sdl", SDL_GetError());
 
@@ -280,6 +279,7 @@ emu_init(void)
 	deadline_interval = ms_interval * TIMEOUT_MS;
 	exec_deadline = SDL_GetPerformanceCounter() + deadline_interval;
 	screen_resize(WIDTH, HEIGHT);
+    SDL_PauseAudioDevice(audio_id, 0);
 	return 1;
 }
 
@@ -541,7 +541,11 @@ emu_end(Uxn *u)
 int
 main(int argc, char **argv)
 {
+    Uint8 dev[0x100] = {0};
 	Uxn u = {0};
+	u.dev = &dev;
+	Uxn u_audio = {0};
+	u_audio.dev = &dev;
 	int i = 1;
 	if(i == argc)
 		return system_error("usage", "uxnemu [-v] | uxnemu [-f | -2x | -3x | --] file.rom [args...]");
@@ -559,10 +563,16 @@ main(int argc, char **argv)
 		}
 	}
 	/* Start system. */
-	if(!emu_init())
-		return system_error("Init", "Failed to initialize varvara.");
-	if(!system_init(&u, (Uint8 *)calloc(0x10000 * RAM_PAGES, sizeof(Uint8)), argv[i++]))
+	Uint8 *ram = (Uint8 *)calloc(0x10000 * RAM_PAGES, sizeof(Uint8));
+	char *rom = argv[i++];
+	if(!system_init(&u, ram, rom)) {
 		return system_error("Init", "Failed to initialize uxn.");
+    }
+	if(!system_init(&u_audio, ram, rom)) {
+		return system_error("Init", "Failed to initialize uxn.");
+    }
+	if(!emu_init(&u_audio))
+		return system_error("Init", "Failed to initialize varvara.");
 	/* Game Loop */
 	u.dev[0x17] = argc - i;
 	if(uxn_eval(&u, PAGE_PROGRAM)) {