From 8f6c8774de7cc7da4d2f4ffd093a69675e659556 Mon Sep 17 00:00:00 2001
From: John Alanbrook <john@pockle.world>
Date: Sun, 15 Jan 2023 17:16:25 +0000
Subject: [PATCH] Optimize busses

---
 source/engine/sound.c     | 42 ++++++++++++++++++++++++++++++++++----
 source/engine/sound.h     |  7 +++++--
 source/engine/sound/mix.c | 43 +++++++++++++++++++++++++++++++--------
 source/engine/sound/mix.h | 15 +++++++-------
 4 files changed, 85 insertions(+), 22 deletions(-)

diff --git a/source/engine/sound.c b/source/engine/sound.c
index 3dfac30..7b0753e 100644
--- a/source/engine/sound.c
+++ b/source/engine/sound.c
@@ -9,6 +9,8 @@
 #include "music.h"
 #include "stb_vorbis.h"
 
+#include "stb_ds.h"
+
 #include "mix.h"
 #include "dsp.h"
 
@@ -28,6 +30,11 @@
 #define TML_IMPLEMENTATION
 #include "tml.h"
 
+static struct {
+    char *key;
+    struct wav *value;
+} *wavhash = NULL;
+
 const char *audioDriver;
 
 void new_samplerate(short *in, short *out, int n, int ch, int sr_in, int sr_out)
@@ -150,20 +157,39 @@ void audio_close()
     //Mix_CloseAudio();
 }
 
-static struct wav mwav;
-
 struct wav *make_sound(const char *wav)
 {
+    int index = shgeti(wavhash, wav);
+    if (index != -1) return wavhash[index].value;
+
+    struct wav mwav;
     mwav.data = drwav_open_file_and_read_pcm_frames_s16(wav, &mwav.ch, &mwav.samplerate, &mwav.frames, NULL);
 
-    if (mwav.samplerate != SAMPLERATE) {
+    if (mwav->samplerate != SAMPLERATE) {
         YughInfo("Changing samplerate of %s.", wav);
         mwav = change_samplerate(mwav, 48000);
     }
 
     mwav.gain = 1.f;
 
-    return &mwav;
+    struct wav *newwav = malloc(sizeof(*newwav));
+    *newwav = mwav;
+
+    if (shlen(wavhash) == 0) sh_new_arena(wavhash);
+
+    shput(wavhash, wav, newwav);
+
+    return newwav;
+}
+
+void free_sound(const char *wav)
+{
+    struct wav *w = shget(wavhash, wav);
+    if (w == NULL) return;
+
+    free(w->data);
+    free(w);
+    shdel(wavhash, wav);
 }
 
 struct soundstream *soundstream_make()
@@ -173,6 +199,14 @@ struct soundstream *soundstream_make()
     return new;
 }
 
+void play_oneshot(struct wav *wav) {
+    struct sound *new = calloc(1, sizeof(*new));
+    new->data = wav;
+    new->bus = first_free_bus(dsp_filter(new, sound_fillbuf));
+    new->playing=1;
+    new->loop=0;
+}
+
 struct sound *play_sound(struct wav *wav)
 {
     struct sound *new = calloc(1, sizeof(*new));
diff --git a/source/engine/sound.h b/source/engine/sound.h
index 43e5afb..ccc587d 100644
--- a/source/engine/sound.h
+++ b/source/engine/sound.h
@@ -29,9 +29,10 @@ struct soundconvstream {
 
 struct soundstream *soundstream_make();
 
+/* A playing sound;
 struct sound {
     int loop;
-    int frame;
+    unsigned int frame;
     int playing;
     float gain;
 
@@ -39,6 +40,7 @@ struct sound {
     struct bus *bus;
 };
 
+/* Represents a sound file */
 struct wav {
     unsigned int ch;
     unsigned int samplerate;
@@ -62,6 +64,7 @@ void audio_close();
 void sound_fillbuf(struct sound *s, short *buf, int n);
 
 struct wav *make_sound(const char *wav);
+void free_sound(const char *wav);
 void wav_norm_gain(struct wav *w, double lv);
 struct sound *play_sound(struct wav *wav);
 
@@ -73,7 +76,7 @@ void sound_pause(struct sound *s);
 void sound_resume(struct sound *s);
 void sound_stop(struct sound *s);
 
-struct music make_music(const char *ogg);
+struct music make_music(const char *mp3);
 
 const char *get_audio_driver();
 
diff --git a/source/engine/sound/mix.c b/source/engine/sound/mix.c
index 5ec531e..8d36401 100644
--- a/source/engine/sound/mix.c
+++ b/source/engine/sound/mix.c
@@ -6,37 +6,62 @@
 #include <string.h>
 
 static struct bus bus[256];
+static int first = 0; /* First bus available */
+static int first_on = -1;
 short mastermix[BUF_FRAMES*CHANNELS];
 
-struct bus *first_free_bus(struct dsp_filter in) {
+void mixer_init() {
     for (int i = 0; i < 256; i++) {
-        if (!bus[i].on) {
-            bus[i].on = 1;
-            bus[i].in = in;
-            return &bus[i];
-        }
+        bus[i].next = i+1;
+        bus[i].on = 0;
+        bus[i].id = i;
     }
 
-    return NULL;
+    bus[255].next = -1;
+}
+
+struct bus *first_free_bus(struct dsp_filter in) {
+    if (first == -1) return NULL;
+    struct bus *ret = bus[first];
+    first = ret->next;
+    ret->on = 1;
+    ret->in = in;
+
+    ret->next = first_on;
+    first_on = ret->id;
+
+    return ret;
 }
 
 void bus_free(struct bus *bus)
 {
+    bus->next = first;
     bus->on = 0;
+    first = bus->id;
 }
 
 void bus_fill_buffers(short *master, int n) {
+    int curbus = first_one
+    memset(master, 0, BUF_FRAMES*CHANNELS*sizeof(short));
+    while (bus[curbus].next != -1) {
+        dsp_run(bus[curbus].in, bus[curbus].buf, BUF_FRAMES);
+        for (int i = 0; i < BUF_FRAMES*CHANNELS; i++)
+            master[i] += bus[curbus].buf[i];
+
+        curbus = bus[curbus].next;
+    }
+
+    /*
     for (int i = 0; i < 256; i++) {
         if (bus[i].on != 1) continue;
         dsp_run(bus[i].in, bus[i].buf, BUF_FRAMES);
     }
 
-    memset(master, 0, BUF_FRAMES*CHANNELS*sizeof(short));
-
         for (int j = 0; j < 256; j++) {
             if (!bus[j].on) continue;
             for (int i = 0; i < BUF_FRAMES*CHANNELS; i++) {
                 master[i] += bus[j].buf[i];
             }
         }
+            */
 }
diff --git a/source/engine/sound/mix.h b/source/engine/sound/mix.h
index 9265154..e746341 100644
--- a/source/engine/sound/mix.h
+++ b/source/engine/sound/mix.h
@@ -7,22 +7,23 @@ struct sound;
 
 
 struct bus {
-    int on;
     struct dsp_filter in;
     short buf[BUF_FRAMES*CHANNELS];
     float gain;
-};
-
-struct listener {
-    float x;
-    float y;
-    float z;
+    int on;
+    int next; /* Next available bus */
+    int prev;
+    int id;
 };
 
 extern short mastermix[BUF_FRAMES*CHANNELS];
 
+void mixer_init();
+
 struct bus *first_free_bus(struct dsp_filter in);
 void bus_fill_buffers(short *master, int n);
+
+
 void bus_free(struct bus *bus);