Get WebAudio context creation working, including error handling

src/Audio.c

@@ -717,6 +717,67 @@ cc_bool Audio_DescribeError(cc_result res, cc_string* dst) {
 	if (err) String_AppendConst(dst, err);
 	return err != NULL;
 }
+#elif defined CC_BUILD_WEBAUDIO
+/*########################################################################################################################*
+*-----------------------------------------------------WebAudio backend----------------------------------------------------*
+*#########################################################################################################################*/
+struct AudioContext { int contextID; };
+extern int  interop_InitAudio(void);
+extern int  interop_AudioCreate(void);
+extern void interop_AudioClose(int contextID);
+extern int  interop_AudioPlay(int contextID, const char* name);
+extern int  interop_AudioDescribe(int res, char* buffer, int bufferLen);
+
+static cc_bool AudioBackend_Init(void) {
+	cc_result res = interop_InitAudio();
+	if (res) { AudioWarn(res, "initing WebAudio context"); return false; }
+
+	InitFakeSounds();
+	return true;
+}
+
+void Audio_Init(struct AudioContext* ctx, int buffers) {
+}
+
+void Audio_Close(struct AudioContext* ctx) {
+	if (ctx->contextID) interop_AudioClose(ctx->contextID);
+	ctx->contextID = 0;
+}
+
+cc_result Audio_SetFormat(struct AudioContext* ctx, int channels, int sampleRate) {
+	return ERR_NOT_SUPPORTED;
+}
+
+cc_result Audio_QueueData(struct AudioContext* ctx, void* data, cc_uint32 size) {
+	return ERR_NOT_SUPPORTED;
+}
+
+cc_result Audio_Play(struct AudioContext* ctx) {
+	return ERR_NOT_SUPPORTED;
+}
+
+cc_result Audio_Poll(struct AudioContext* ctx, int* inUse) {
+	return ERR_NOT_SUPPORTED;
+}
+
+cc_bool Audio_FastPlay(struct AudioContext* ctx, int channels, int sampleRate) {
+	/* Channels/Sample rate is per buffer, not a per source property */
+	return true;
+}
+
+cc_result Audio_PlaySound(struct AudioContext* ctx, struct Sound* snd, int volume) {
+	if (!ctx->contextID) 
+		ctx->contextID = interop_AudioCreate();
+	return interop_AudioPlay(ctx->contextID, snd->data);
+}
+
+cc_bool Audio_DescribeError(cc_result res, cc_string* dst) {
+	char buffer[NATIVE_STR_LEN];
+	int len = interop_AudioDescribe(res, buffer, NATIVE_STR_LEN);
+
+	String_AppendUtf8(dst, buffer, len);
+	return len > 0;
+}
 #endif
 
 /*########################################################################################################################*
@@ -989,6 +1050,12 @@ static void Sounds_LoadFile(const cc_string* path, void* obj) {
 	Soundboard_Load(&stepBoard, &step, path);
 }
 
+/* TODO this is a pretty terrible solution */
+#ifdef CC_BUILD_WEBAUDIO
+static void InitWebSounds(void) {
+}
+#endif
+
 static cc_bool sounds_loaded;
 static void Sounds_Start(void) {
 	int i;
@@ -1004,7 +1071,11 @@ static void Sounds_Start(void) {
 
 	if (sounds_loaded) return;
 	sounds_loaded = true;
+#ifdef CC_BUILD_WEBAUDIO
+	InitWebSounds();
+#else
 	Directory_Enum(&audio_dir, NULL, Sounds_LoadFile);
+#endif
 }
 
 static void Sounds_Stop(void) {

src/Core.h

@@ -239,7 +239,7 @@ Thus it is **NOT SAFE** to allocate a string on the stack. */
 #define CC_BUILD_GLMODERN
 #define CC_BUILD_GLES
 #define CC_BUILD_TOUCH
-#define CC_BUILD_NOSOUNDS
+#define CC_BUILD_WEBAUDIO
 #define CC_BUILD_NOMUSIC
 #define CC_BUILD_MINFILES
 #endif

src/interop_web.js

@@ -660,5 +660,85 @@ mergeInto(LibraryManager.library, {
     var dbg = GLctx.getExtension('WEBGL_debug_renderer_info');
     var str = dbg ? GLctx.getParameter(dbg.UNMASKED_RENDERER_WEBGL) : "";
     stringToUTF8(str, buffer, len);
-  }
+  },
+  
+
+//########################################################################################################################
+//---------------------------------------------------------Sockets--------------------------------------------------------
+//########################################################################################################################
+  interop_AudioLog: function(err) {
+    console.log(err);
+    window.AUDIO.errors.push(''+err);
+    return window.AUDIO.errors.length|0;
+  },
+  interop_InitAudio: function() {
+    window.AUDIO = window.AUDIO || {
+      context: null,
+      sources: [],
+      buffers: {},
+      errors: [],
+      seen: {},
+    };
+    if (window.AUDIO.context) return 0;
+
+    // TODO error handling everywhere
+    try {
+      if (window.AudioContext) {
+        AUDIO.context = new window.AudioContext();
+      } else {
+        AUDIO.context = new window.webkitAudioContext();
+      }
+    } catch (err) {
+      return _interop_AudioLog(err)
+    }
+    return 0;
+  },
+  interop_InitAudio__deps: ['interop_AudioLog'],
+  interop_AudioCreate: function() {
+    var source = AUDIO.context.createBufferSource();
+    AUDIO.sources.push(source);
+    return AUDIO.sources.length|0; 
+    // NOTE: 0 is used by Audio.c for "no source"
+  },
+  interop_AudioClose: function(ctxID) {
+    var source = AUDIO.sources[ctxID - 1|0];
+    source.stop();
+    AUDIO.sources[ctxID - 1|0] = null;
+  },
+  interop_AudioPlay: function(ctxID, name) {
+    var source = AUDIO.sources[ctxID - 1|0];
+    var name_  = UTF8ToString(name);
+    
+    // have we already downloaded or are downloading this file?
+    if (!AUDIO.seen.hasOwnProperty(name_)) {
+      Audio.seen[name_] = true;
+      _interop_AudioDownload(name_);
+      return 0;
+    }
+    
+    source.buffer = AUDIO.buffers[name_];
+    source.connect(audioCtx.destination);
+    source.start();
+    return 0;
+  },
+  interop_AudioPlay__deps: ['interop_AudioDownload'],
+  interop_AudioDownload: function(name) {
+    var xhr = new XMLHttpRequest();
+    xhr.open('GET', 'static/' + name + '.wav', true);   
+    xhr.responseType = 'arraybuffer';
+    
+    xhr.onload = function() {
+      var data = xhr.response;
+      AUDIO.context.decodeAudioData(data, function(buffer) {
+          AUDIO.buffers[name] = buffer;
+        });
+    };
+    xhr.send();
+  },
+  interop_AudioDescribe: function(errCode, buffer, bufferLen) {
+    if (errCode > AUDIO.errors.length) return 0;
+    
+    var str = AUDIO.errors[errCode - 1];
+    return stringToUTF8(str, buffer, bufferLen);
+  },
 });