From c4e9058ee26841baae4c0fd51e081949747d5f48 Mon Sep 17 00:00:00 2001
From: Justin Kerk <dopefishjustin@gmail.com>
Date: Tue, 22 Jul 2014 04:51:52 +0000
Subject: [PATCH] [JSMESS] Add shim for Web Audio sound module [Katelyn Gadd,
 Justin Kerk]

---
 .gitattributes                   |  2 ++
 src/osd/modules/sound/js_sound.c | 39 ++++++++++++++++++++++++++++++++
 src/osd/modules/sound/js_sound.h | 31 +++++++++++++++++++++++++
 src/osd/sdl/sdl.mak              |  6 +++++
 src/osd/sdl/sdlmain.c            |  8 +++++++
 5 files changed, 86 insertions(+)
 create mode 100644 src/osd/modules/sound/js_sound.c
 create mode 100644 src/osd/modules/sound/js_sound.h

diff --git a/.gitattributes b/.gitattributes
index 0465c977fcb..105d9b950d0 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -9303,6 +9303,8 @@ src/osd/modules/debugger/qt/debugqtwindow.c svneol=native#text/plain
 src/osd/modules/debugger/qt/debugqtwindow.h svneol=native#text/plain
 src/osd/modules/sound/direct_sound.c svneol=native#text/plain
 src/osd/modules/sound/direct_sound.h svneol=native#text/plain
+src/osd/modules/sound/js_sound.c svneol=native#text/plain
+src/osd/modules/sound/js_sound.h svneol=native#text/plain
 src/osd/modules/sound/none.c svneol=native#text/plain
 src/osd/modules/sound/none.h svneol=native#text/plain
 src/osd/modules/sound/sdl_sound.c svneol=native#text/plain
diff --git a/src/osd/modules/sound/js_sound.c b/src/osd/modules/sound/js_sound.c
new file mode 100644
index 00000000000..a2bc6086343
--- /dev/null
+++ b/src/osd/modules/sound/js_sound.c
@@ -0,0 +1,39 @@
+// license:BSD-3-Clause
+// copyright-holders:Miodrag Milanovic, Katelyn Gadd
+/***************************************************************************
+
+    js_sound.c
+
+    Shim for native JavaScript sound interface implementations (Emscripten only).
+
+*******************************************************************c********/
+
+
+#include "js_sound.h"
+#include "emscripten.h"
+
+//-------------------------------------------------
+//  sound_js - constructor
+//-------------------------------------------------
+sound_js::sound_js(const osd_interface &osd)
+	: osd_sound_interface(osd)
+{
+}
+
+void sound_js::update_audio_stream(const INT16 *buffer, int samples_this_frame)
+{
+  EM_ASM_ARGS({
+    // Forward audio stream update on to JS backend implementation.
+    jsmess_update_audio_stream($0, $1); 
+  }, (unsigned int)buffer, samples_this_frame);
+}
+
+void sound_js::set_mastervolume(int attenuation)
+{
+  EM_ASM_ARGS({
+    // Forward volume update on to JS backend implementation.
+    jsmess_set_mastervolume($0); 
+  }, attenuation);
+}
+
+const osd_sound_type OSD_SOUND_JS = &osd_sound_creator<sound_js>;
diff --git a/src/osd/modules/sound/js_sound.h b/src/osd/modules/sound/js_sound.h
new file mode 100644
index 00000000000..ad0785fe960
--- /dev/null
+++ b/src/osd/modules/sound/js_sound.h
@@ -0,0 +1,31 @@
+// license:BSD-3-Clause
+// copyright-holders:Miodrag Milanovic, Katelyn Gadd
+/***************************************************************************
+
+    js_sound.h
+
+    Shim for native JavaScript sound interface implementations (Emscripten only).
+
+*******************************************************************c********/
+
+#pragma once
+
+#ifndef __SOUND_JS_H__
+#define __SOUND_JS_H__
+
+#include "osdepend.h"
+
+class sound_js : public osd_sound_interface
+{
+public:
+	// construction/destruction
+	sound_js(const osd_interface &osd);
+	virtual ~sound_js() { }
+	
+	virtual void update_audio_stream(const INT16 *buffer, int samples_this_frame);
+	virtual void set_mastervolume(int attenuation);
+};
+
+extern const osd_sound_type OSD_SOUND_JS;
+
+#endif  /* __SOUND_JS_H__ */
diff --git a/src/osd/sdl/sdl.mak b/src/osd/sdl/sdl.mak
index 43ee7e4afce..3e67d0cbe6f 100644
--- a/src/osd/sdl/sdl.mak
+++ b/src/osd/sdl/sdl.mak
@@ -417,6 +417,12 @@ endif
 # add an ARCH define
 DEFS += -DSDLMAME_ARCH="$(ARCHOPTS)" -DSYNC_IMPLEMENTATION=$(SYNC_IMPLEMENTATION)
 
+# Add JavaScript sound module for Emscripten compiles
+
+ifeq ($(TARGETOS),emscripten)
+OSDOBJS += $(OSDOBJ)/modules/sound/js_sound.o
+endif
+
 #-------------------------------------------------
 # Generic defines and additions
 #-------------------------------------------------
diff --git a/src/osd/sdl/sdlmain.c b/src/osd/sdl/sdlmain.c
index 2cabef9012d..f4b52598c20 100644
--- a/src/osd/sdl/sdlmain.c
+++ b/src/osd/sdl/sdlmain.c
@@ -50,6 +50,9 @@
 #include "osdsdl.h"
 #include "sdlos.h"
 #include "modules/sound/sdl_sound.h"
+#if defined(SDLMAME_EMSCRIPTEN)
+#include "modules/sound/js_sound.h"
+#endif
 #if !defined(NO_DEBUGGER)
 #include "modules/debugger/debugqt.h"
 #endif
@@ -540,7 +543,12 @@ void sdl_osd_interface::video_register()
 void sdl_osd_interface::sound_register()
 {
 	sound_options_add("sdl", OSD_SOUND_SDL);
+#if defined(SDLMAME_EMSCRIPTEN)
+	sound_options_add("js", OSD_SOUND_JS);
+	sound_options_add("auto", OSD_SOUND_JS); // making JS audio default one
+#else
 	sound_options_add("auto", OSD_SOUND_SDL); // making SDL audio default one
+#endif
 }
 
 //============================================================