From 7b3554fd3c5a3d75e7955fb0c314634e98acbb30 Mon Sep 17 00:00:00 2001
From: Toad King <toadking@toadking.com>
Date: Sun, 14 Jan 2018 20:46:08 -0600
Subject: [PATCH 01/18] fix crash in cores than send audio early

---
 emscripten/library_rwebaudio.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/emscripten/library_rwebaudio.js b/emscripten/library_rwebaudio.js
index fd85d607a0..49c0d2d015 100644
--- a/emscripten/library_rwebaudio.js
+++ b/emscripten/library_rwebaudio.js
@@ -23,7 +23,7 @@ var LibraryRWebAudio = {
 
       getCurrentPerfTime: function() {
          if (RA.startTime) return (window['performance']['now']() - RA.startTime) / 1000;
-         else throw 'getCurrentPerfTime() called before start time set';
+         else return 0;
       },
 
       process: function(queueBuffers) {
@@ -97,7 +97,7 @@ var LibraryRWebAudio = {
       Module["pauseMainLoop"]();
       return 1;
    },
-   
+
    RWebAudioSampleRate: function() {
       return RA.context.sampleRate;
    },

From a682ccd8e8956725f1166454cc5dfd4aa2863f85 Mon Sep 17 00:00:00 2001
From: Toad King <toadking@toadking.com>
Date: Sun, 14 Jan 2018 21:02:59 -0600
Subject: [PATCH 02/18] fix menu button

---
 pkg/emscripten/libretro/index.html  |  2 +-
 pkg/emscripten/libretro/libretro.js | 26 +-------------------------
 2 files changed, 2 insertions(+), 26 deletions(-)

diff --git a/pkg/emscripten/libretro/index.html b/pkg/emscripten/libretro/index.html
index 7651ad525e..fea47989e0 100644
--- a/pkg/emscripten/libretro/index.html
+++ b/pkg/emscripten/libretro/index.html
@@ -86,7 +86,7 @@
                            <span class="fa fa-trash-o" id="icnClean"></span> <span class="sr-only">Cleanup</span>
                         </button>
                         <input class="btn btn-primary disabled" style="display: none" type="file" id="btnRom" name="upload" onclick="document.getElementById('btnAdd').click();" onchange="selectFiles(event.target.files)" multiple />
-                        <button class="btn btn-primary disabled tooltip-enable" id="btnMenu" onclick="keyPress(112);" title="Menu toggle" disabled>
+                        <button class="btn btn-primary disabled tooltip-enable" id="btnMenu" onclick="keyPress('F1');" title="Menu toggle" disabled>
                            <span class="fa fa-bars" id="btnMenu"></span> <span class="sr-only">Menu</span>
                         </button>
                         <button class="btn btn-primary disabled tooltip-enable" id="btnFullscreen" onclick="Module.requestFullScreen()" title="Fullscreen" disabled>
diff --git a/pkg/emscripten/libretro/libretro.js b/pkg/emscripten/libretro/libretro.js
index 300c6ff1bd..fa5c78f03c 100644
--- a/pkg/emscripten/libretro/libretro.js
+++ b/pkg/emscripten/libretro/libretro.js
@@ -393,31 +393,7 @@ function keyPress(k)
 }
 
 kp = function(k, event) {
-   var oEvent = document.createEvent('KeyboardEvent');
-
-   // Chromium Hack
-   Object.defineProperty(oEvent, 'keyCode', {
-      get : function() {
-         return this.keyCodeVal;
-      }
-   });
-   Object.defineProperty(oEvent, 'which', {
-      get : function() {
-         return this.keyCodeVal;
-      }
-   });
-
-   if (oEvent.initKeyboardEvent) {
-      oEvent.initKeyboardEvent(event, true, true, document.defaultView, false, false, false, false, k, k);
-   } else {
-      oEvent.initKeyEvent(event, true, true, document.defaultView, false, false, false, false, k, 0);
-   }
-
-   oEvent.keyCodeVal = k;
-
-   if (oEvent.keyCode !== k) {
-      alert("keyCode mismatch " + oEvent.keyCode + "(" + oEvent.which + ")");
-   }
+   var oEvent = new KeyboardEvent(event, { code: k });
 
    document.dispatchEvent(oEvent);
    document.getElementById('canvas').focus();

From 4498e9ffba0aa084a8ffeca209634972fa14622b Mon Sep 17 00:00:00 2001
From: Toad King <toadking@toadking.com>
Date: Sun, 14 Jan 2018 21:10:15 -0600
Subject: [PATCH 03/18] fix white bar in chrome when fullscreen

---
 pkg/emscripten/libretro/libretro.css | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/pkg/emscripten/libretro/libretro.css b/pkg/emscripten/libretro/libretro.css
index d5e6b52d89..299bb730b6 100644
--- a/pkg/emscripten/libretro/libretro.css
+++ b/pkg/emscripten/libretro/libretro.css
@@ -92,8 +92,13 @@ textarea {
     font-size: 0.7em;
     height: 95%;
     width:  95%;
-    border-style: none; 
-    border-color: transparent; 
+    border-style: none;
+    border-color: transparent;
     overflow: auto;
     resize: none;
 }
+
+/* fix weird white bar in chrome when fullscreen */
+:-webkit-full-screen {
+  height: 100%;
+}

From 2df70cce17a06f62d970da20b95d4be430c5087c Mon Sep 17 00:00:00 2001
From: Toad King <toadking@toadking.com>
Date: Sun, 14 Jan 2018 21:18:30 -0600
Subject: [PATCH 04/18] make retroarch logs log to web console instead of
 textbox

---
 pkg/emscripten/libretro/index.html  |  9 ---------
 pkg/emscripten/libretro/libretro.js | 19 ++++---------------
 2 files changed, 4 insertions(+), 24 deletions(-)

diff --git a/pkg/emscripten/libretro/index.html b/pkg/emscripten/libretro/index.html
index fea47989e0..9c6cc8be3d 100644
--- a/pkg/emscripten/libretro/index.html
+++ b/pkg/emscripten/libretro/index.html
@@ -124,15 +124,6 @@
             </div>
          </div>
       </div>
-      <div class="row">
-         <div class="col-sm-12 form-group btn-group text-xs-center p-t-2">
-            <div class="card">
-                <div class="view overlay hm-white-slight" align="center">
-                     <textarea id="output" rows="15"></textarea>
-                </div>
-            </div>
-         </div>
-      </div>
    </div>
    <div align="center">
       <p>For now, we recommend you use <a href="https://www.google.com/chrome/">Google Chrome</a> for the best possible performance.</p>
diff --git a/pkg/emscripten/libretro/libretro.js b/pkg/emscripten/libretro/libretro.js
index fa5c78f03c..8e3463dd82 100644
--- a/pkg/emscripten/libretro/libretro.js
+++ b/pkg/emscripten/libretro/libretro.js
@@ -268,24 +268,13 @@ var Module =
   arguments: ["-v", "--menu"],
   preRun: [],
   postRun: [],
-  print: (function()
+  print: function(text)
   {
-     var element = document.getElementById('output');
-     element.value = ''; // clear browser cache
-     return function(text)
-     {
-        text = Array.prototype.slice.call(arguments).join(' ');
-        element.value += text + "\n";
-        element.scrollTop = 99999; // focus on bottom
-     };
-  })(),
-
+     console.log(text);
+  },
   printErr: function(text)
   {
-     var text = Array.prototype.slice.call(arguments).join(' ');
-     var element = document.getElementById('output');
-     element.value += text + "\n";
-     element.scrollTop = 99999; // focus on bottom
+     console.log(text);
   },
   canvas: document.getElementById('canvas'),
   totalDependencies: 0,

From 6f77859eed7ef1f0a99fa6ed7f9f72e81952eba3 Mon Sep 17 00:00:00 2001
From: Toad King <toadking@toadking.com>
Date: Sun, 14 Jan 2018 22:56:53 -0600
Subject: [PATCH 05/18] fixes to rwebaudio

it should no longer mark buffers for clear if they're still being filled
report correct total buffer size to help resampler
---
 emscripten/library_rwebaudio.js | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/emscripten/library_rwebaudio.js b/emscripten/library_rwebaudio.js
index 49c0d2d015..242c599500 100644
--- a/emscripten/library_rwebaudio.js
+++ b/emscripten/library_rwebaudio.js
@@ -29,7 +29,8 @@ var LibraryRWebAudio = {
       process: function(queueBuffers) {
          var currentTime = RA.getCurrentPerfTime();
          for (var i = 0; i < RA.bufIndex; i++) {
-            if (RA.buffers[i].endTime < currentTime) {
+            if (RA.buffers[i].endTime !== 0 && RA.buffers[i].endTime < currentTime) {
+               RA.buffers[i].endTime = 0;
                var buf = RA.buffers.splice(i, 1);
                RA.buffers[RA.numBuffers - 1] = buf[0];
                i--;
@@ -87,7 +88,10 @@ var LibraryRWebAudio = {
       RA.numBuffers = ((latency * RA.context.sampleRate) / (1000 * RA.BUFFER_SIZE))|0;
       if (RA.numBuffers < 2) RA.numBuffers = 2;
 
-      for (var i = 0; i < RA.numBuffers; i++) RA.buffers[i] = RA.context.createBuffer(2, RA.BUFFER_SIZE, RA.context.sampleRate);
+      for (var i = 0; i < RA.numBuffers; i++) {
+         RA.buffers[i] = RA.context.createBuffer(2, RA.BUFFER_SIZE, RA.context.sampleRate);
+         RA.buffers[i].endTime = 0
+      }
 
       RA.nonblock = false;
       RA.startTime = 0;
@@ -146,7 +150,7 @@ var LibraryRWebAudio = {
    },
 
    RWebAudioBufferSize: function() {
-      return RA.numBuffers * RA.BUFFER_SIZE + RA.BUFFER_SIZE;
+      return RA.numBuffers * RA.BUFFER_SIZE * 8;
    },
 
    RWebAudioWriteAvail: function() {

From 2d3fc1a38495397801a7dddf85b9e92d332b8da0 Mon Sep 17 00:00:00 2001
From: Toad King <toadking@toadking.com>
Date: Sun, 14 Jan 2018 22:59:06 -0600
Subject: [PATCH 06/18] update gitignore

---
 .gitignore | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/.gitignore b/.gitignore
index 60c69dd615..263b03b50c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -132,3 +132,9 @@ obj-unix/
 /pkg/msvc/msvc-2010/Release Cg/*.pdb
 retroarch.cfg
 Makefile.local
+
+# Emscripten artifacts
+
+retroarch.js
+retroarch.js.mem
+*.bc

From b75f4b4f6708726d7c8def5a9a829298aa3caa98 Mon Sep 17 00:00:00 2001
From: Toad King <toadking@toadking.com>
Date: Sun, 14 Jan 2018 23:29:20 -0600
Subject: [PATCH 07/18] implement setting vsync and swapinterval

vsync is not "true" vsync (that's always on in browsers) but changes the main loop timer from immediate to window.requestAnimationFrame
---
 frontend/drivers/platform_emscripten.c  | 3 +--
 gfx/drivers_context/emscriptenegl_ctx.c | 7 +++++--
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/frontend/drivers/platform_emscripten.c b/frontend/drivers/platform_emscripten.c
index 838f3e365e..0478641018 100644
--- a/frontend/drivers/platform_emscripten.c
+++ b/frontend/drivers/platform_emscripten.c
@@ -173,8 +173,7 @@ int main(int argc, char *argv[])
    emscripten_set_canvas_element_size("#canvas", 800, 600);
    emscripten_set_element_css_size("#canvas", 800.0, 600.0);
    rarch_main(argc, argv, NULL);
-   emscripten_set_main_loop(emscripten_mainloop,
-         settings->bools.video_vsync ? 0 : INT_MAX, 1);
+   emscripten_set_main_loop(emscripten_mainloop, 0, 1);
 
    return 0;
 }
diff --git a/gfx/drivers_context/emscriptenegl_ctx.c b/gfx/drivers_context/emscriptenegl_ctx.c
index e72434b5cb..4bfa4077b1 100644
--- a/gfx/drivers_context/emscriptenegl_ctx.c
+++ b/gfx/drivers_context/emscriptenegl_ctx.c
@@ -51,8 +51,11 @@ static int emscripten_initial_height;
 static void gfx_ctx_emscripten_swap_interval(void *data, unsigned interval)
 {
    (void)data;
-   /* no way to control VSync in WebGL. */
-   (void)interval;
+
+   if (interval == 0)
+      emscripten_set_main_loop_timing(EM_TIMING_SETIMMEDIATE, 0);
+   else
+      emscripten_set_main_loop_timing(EM_TIMING_RAF, (int)interval);
 }
 
 static void gfx_ctx_emscripten_get_canvas_size(int *width, int *height)

From db152fede8f6cacba67495d2e801b99f713f3fab Mon Sep 17 00:00:00 2001
From: Toad King <toadking@toadking.com>
Date: Sun, 14 Jan 2018 23:45:54 -0600
Subject: [PATCH 08/18] remove container with uneeded padding. fixes canvas
 being off-center in smaller windows

---
 pkg/emscripten/libretro/index.html | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/pkg/emscripten/libretro/index.html b/pkg/emscripten/libretro/index.html
index 9c6cc8be3d..068e0b6bd6 100644
--- a/pkg/emscripten/libretro/index.html
+++ b/pkg/emscripten/libretro/index.html
@@ -100,11 +100,9 @@
        </div>
    </nav>
    <div class="bg-inverse webplayer-container">
-      <div class="container">
-         <div class="webplayer_border text-xs-center" id="canvas_div">
-            <canvas class="webplayer" id="canvas" tabindex="1" oncontextmenu="event.preventDefault()" style="display: none"></canvas>
-            <img class="webplayer-preview img-fluid" src="media/canvas.png" width="960px" height="720px" alt="RetroArch Logo">
-         </div>
+      <div class="webplayer_border text-xs-center" id="canvas_div">
+         <canvas class="webplayer" id="canvas" tabindex="1" oncontextmenu="event.preventDefault()" style="display: none"></canvas>
+         <img class="webplayer-preview img-fluid" src="media/canvas.png" width="960px" height="720px" alt="RetroArch Logo">
       </div>
    </div>
    <div class="container">

From 1c1b35708affc4b10c9ae8ea0fc357c96cb22e2c Mon Sep 17 00:00:00 2001
From: Toad King <toadking@toadking.com>
Date: Mon, 15 Jan 2018 00:06:57 -0600
Subject: [PATCH 09/18] fix default joypad driver on emscripten

---
 configuration.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/configuration.c b/configuration.c
index 9e7eacc246..6a70465a0c 100644
--- a/configuration.c
+++ b/configuration.c
@@ -224,6 +224,7 @@ enum joypad_driver_enum
    JOYPAD_DOS,
    JOYPAD_HID,
    JOYPAD_QNX,
+   JOYPAD_RWEBPAD,
    JOYPAD_NULL
 };
 
@@ -454,6 +455,8 @@ static enum joypad_driver_enum JOYPAD_DEFAULT_DRIVER = JOYPAD_DOS;
 static enum joypad_driver_enum JOYPAD_DEFAULT_DRIVER = JOYPAD_HID;
 #elif defined(__QNX__)
 static enum joypad_driver_enum JOYPAD_DEFAULT_DRIVER = JOYPAD_QNX;
+#elif defined(EMSCRIPTEN)
+static enum joypad_driver_enum JOYPAD_DEFAULT_DRIVER = JOYPAD_RWEBPAD;
 #else
 static enum joypad_driver_enum JOYPAD_DEFAULT_DRIVER = JOYPAD_NULL;
 #endif
@@ -783,9 +786,9 @@ const char *config_get_default_input(void)
       case INPUT_COCOA:
          return "cocoa";
       case INPUT_QNX:
-      	 return "qnx_input";
+          return "qnx_input";
       case INPUT_RWEBINPUT:
-      	 return "rwebinput";
+          return "rwebinput";
       case INPUT_DOS:
          return "dos";
       case INPUT_NULL:
@@ -846,6 +849,8 @@ const char *config_get_default_joypad(void)
          return "hid";
       case JOYPAD_QNX:
          return "qnx";
+      case JOYPAD_RWEBPAD:
+         return "rwebpad";
       case JOYPAD_DOS:
          return "dos";
       case JOYPAD_NULL:

From 2738c79aa0b2ad7de38ce8e06b7faf07ab477c4c Mon Sep 17 00:00:00 2001
From: Toad King <toadking@toadking.com>
Date: Mon, 15 Jan 2018 00:07:12 -0600
Subject: [PATCH 10/18] switch to RGUI as default menu for emscripten

---
 frontend/drivers/platform_emscripten.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/frontend/drivers/platform_emscripten.c b/frontend/drivers/platform_emscripten.c
index 0478641018..94ab75e24b 100644
--- a/frontend/drivers/platform_emscripten.c
+++ b/frontend/drivers/platform_emscripten.c
@@ -162,8 +162,6 @@ static void frontend_emscripten_get_env(int *argc, char *argv[],
       if (!string_is_empty(dir_path))
          path_mkdir(dir_path);
    }
-
-   snprintf(g_defaults.settings.menu, sizeof(g_defaults.settings.menu), "rgui");
 }
 
 int main(int argc, char *argv[])

From d23faff8d6ef7d5bf4b7f4f2851df9cff120e78f Mon Sep 17 00:00:00 2001
From: Toad King <toadking@toadking.com>
Date: Mon, 15 Jan 2018 00:43:20 -0600
Subject: [PATCH 11/18] set the main loop first before calling rarch_main

---
 frontend/drivers/platform_emscripten.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/frontend/drivers/platform_emscripten.c b/frontend/drivers/platform_emscripten.c
index 94ab75e24b..08bd22cd91 100644
--- a/frontend/drivers/platform_emscripten.c
+++ b/frontend/drivers/platform_emscripten.c
@@ -170,8 +170,8 @@ int main(int argc, char *argv[])
 
    emscripten_set_canvas_element_size("#canvas", 800, 600);
    emscripten_set_element_css_size("#canvas", 800.0, 600.0);
+   emscripten_set_main_loop(emscripten_mainloop, 0, 0);
    rarch_main(argc, argv, NULL);
-   emscripten_set_main_loop(emscripten_mainloop, 0, 1);
 
    return 0;
 }

From 19facdb06600a7be752e83e7c7644f6334474cbe Mon Sep 17 00:00:00 2001
From: Toad King <toadking@toadking.com>
Date: Mon, 15 Jan 2018 02:12:53 -0600
Subject: [PATCH 12/18] reset drivers shortly after toggling fullscreen mode

fixes black screen after going fullscreen in game
---
 frontend/drivers/platform_emscripten.c  | 35 ++++++++++++++++++++++++-
 gfx/drivers_context/emscriptenegl_ctx.c |  9 +++++--
 2 files changed, 41 insertions(+), 3 deletions(-)

diff --git a/frontend/drivers/platform_emscripten.c b/frontend/drivers/platform_emscripten.c
index 08bd22cd91..99c17c5a63 100644
--- a/frontend/drivers/platform_emscripten.c
+++ b/frontend/drivers/platform_emscripten.c
@@ -39,14 +39,38 @@
 #include "../../defaults.h"
 #include "../../content.h"
 #include "../../retroarch.h"
+#include "../../verbosity.h"
 #include "../../command.h"
 #include "../../tasks/tasks_internal.h"
 #include "../../file_path_special.h"
 
+static unsigned emscripten_fullscreen_reinit;
+
+static EM_BOOL emscripten_fullscreenchange_cb(int event_type,
+   const EmscriptenFullscreenChangeEvent *fullscreen_change_event,
+   void *user_data)
+{
+   (void)event_type;
+   (void)fullscreen_change_event;
+   (void)user_data;
+
+   emscripten_fullscreen_reinit = 5;
+
+   return EM_TRUE;
+}
+
 static void emscripten_mainloop(void)
 {
    unsigned sleep_ms = 0;
-   int           ret = runloop_iterate(&sleep_ms);
+   int ret;
+
+   if (emscripten_fullscreen_reinit != 0)
+   {
+      if (--emscripten_fullscreen_reinit == 0)
+         command_event(CMD_EVENT_REINIT, NULL);
+   }
+
+   ret = runloop_iterate(&sleep_ms);
 
    if (ret == 1 && sleep_ms > 0)
       retro_sleep(sleep_ms);
@@ -166,6 +190,7 @@ static void frontend_emscripten_get_env(int *argc, char *argv[],
 
 int main(int argc, char *argv[])
 {
+   EMSCRIPTEN_RESULT r;
    settings_t *settings = config_get_ptr();
 
    emscripten_set_canvas_element_size("#canvas", 800, 600);
@@ -173,6 +198,14 @@ int main(int argc, char *argv[])
    emscripten_set_main_loop(emscripten_mainloop, 0, 0);
    rarch_main(argc, argv, NULL);
 
+   r = emscripten_set_fullscreenchange_callback("#document", NULL, false,
+      emscripten_fullscreenchange_cb);
+   if (r != EMSCRIPTEN_RESULT_SUCCESS)
+   {
+      RARCH_ERR(
+         "[EMSCRIPTEN/CTX] failed to create fullscreen callback: %d\n", r);
+   }
+
    return 0;
 }
 
diff --git a/gfx/drivers_context/emscriptenegl_ctx.c b/gfx/drivers_context/emscriptenegl_ctx.c
index 4bfa4077b1..b3d7f3ae43 100644
--- a/gfx/drivers_context/emscriptenegl_ctx.c
+++ b/gfx/drivers_context/emscriptenegl_ctx.c
@@ -141,8 +141,13 @@ static void gfx_ctx_emscripten_check_window(void *data, bool *quit,
 
 static void gfx_ctx_emscripten_swap_buffers(void *data, void *data2)
 {
-   (void)data;
-   /* no-op in emscripten, no way to force swap/wait for VSync in browsers */
+   emscripten_ctx_data_t *emscripten = (emscripten_ctx_data_t*)data;
+
+   /* doesn't really do anything in WebGL, but it might if we use WebGL workers
+    * in the future */
+#ifdef HAVE_EGL
+   egl_swap_buffers(&emscripten->egl);
+#endif
 }
 
 static void gfx_ctx_emscripten_get_video_size(void *data,

From 0256156a6bf95f6da25db3a4b589a6ca2f270e63 Mon Sep 17 00:00:00 2001
From: Toad King <toadking@toadking.com>
Date: Mon, 15 Jan 2018 03:08:30 -0600
Subject: [PATCH 13/18] fix rwebaudio time drift

fixes audio getting stuck in an always fast state
---
 emscripten/library_rwebaudio.js        | 22 ++++++++++++++--------
 frontend/drivers/platform_emscripten.c |  4 ++++
 2 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/emscripten/library_rwebaudio.js b/emscripten/library_rwebaudio.js
index 242c599500..03b70a8340 100644
--- a/emscripten/library_rwebaudio.js
+++ b/emscripten/library_rwebaudio.js
@@ -41,8 +41,8 @@ var LibraryRWebAudio = {
 
       fillBuffer: function(buf, samples) {
          var count = 0;
-         var leftBuffer = RA.buffers[RA.bufIndex].getChannelData(0);
-         var rightBuffer = RA.buffers[RA.bufIndex].getChannelData(1);
+         const leftBuffer = RA.buffers[RA.bufIndex].getChannelData(0);
+         const rightBuffer = RA.buffers[RA.bufIndex].getChannelData(1);
          while (samples && RA.bufOffset !== RA.BUFFER_SIZE) {
             leftBuffer[RA.bufOffset] = {{{ makeGetValue('buf', 'count * 8', 'float') }}};
             rightBuffer[RA.bufOffset] = {{{ makeGetValue('buf', 'count * 8 + 4', 'float') }}};
@@ -74,7 +74,7 @@ var LibraryRWebAudio = {
       block: function() {
          do {
             RA.process();
-         } while (RA.bufIndex === RA.numBuffers - 1);
+         } while (RA.bufIndex === RA.numBuffers);
       }
    },
 
@@ -112,16 +112,17 @@ var LibraryRWebAudio = {
       var count = 0;
 
       while (samples) {
+         if (RA.bufIndex === RA.numBuffers) {
+            if (RA.nonblock) break;
+            else RA.block();
+         }
+
          var fill = RA.fillBuffer(buf, samples);
          samples -= fill;
          count += fill;
          buf += fill * 8;
 
          if (RA.bufOffset === RA.BUFFER_SIZE) {
-            if (RA.bufIndex === RA.numBuffers - 1) {
-               if (RA.nonblock) break;
-               else RA.block();
-            }
             RA.queueAudio();
          }
       }
@@ -146,7 +147,6 @@ var LibraryRWebAudio = {
    RWebAudioFree: function() {
       RA.bufIndex = 0;
       RA.bufOffset = 0;
-      return;
    },
 
    RWebAudioBufferSize: function() {
@@ -156,6 +156,12 @@ var LibraryRWebAudio = {
    RWebAudioWriteAvail: function() {
       RA.process();
       return ((RA.numBuffers - RA.bufIndex) * RA.BUFFER_SIZE - RA.bufOffset) * 8;
+   },
+
+   RWebAudioRecalibrateTime: function() {
+      if (RA.startTime) {
+         RA.startTime = window['performance']['now']() - RA.context.currentTime * 1000;
+      }
    }
 };
 
diff --git a/frontend/drivers/platform_emscripten.c b/frontend/drivers/platform_emscripten.c
index 99c17c5a63..4982446275 100644
--- a/frontend/drivers/platform_emscripten.c
+++ b/frontend/drivers/platform_emscripten.c
@@ -44,6 +44,8 @@
 #include "../../tasks/tasks_internal.h"
 #include "../../file_path_special.h"
 
+void RWebAudioRecalibrateTime(void);
+
 static unsigned emscripten_fullscreen_reinit;
 
 static EM_BOOL emscripten_fullscreenchange_cb(int event_type,
@@ -64,6 +66,8 @@ static void emscripten_mainloop(void)
    unsigned sleep_ms = 0;
    int ret;
 
+   RWebAudioRecalibrateTime();
+
    if (emscripten_fullscreen_reinit != 0)
    {
       if (--emscripten_fullscreen_reinit == 0)

From 3917b02f9f42a3f59a8c7bc65b20a17ec028d8d8 Mon Sep 17 00:00:00 2001
From: Toad King <toadking@toadking.com>
Date: Mon, 15 Jan 2018 04:00:09 -0600
Subject: [PATCH 14/18] build optimized emscripten builds as WASM

HUGE speed-ups for firefox and moderate speedups for chrome
---
 .gitignore          | 1 +
 Makefile.emscripten | 5 ++---
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/.gitignore b/.gitignore
index 263b03b50c..71db6addba 100644
--- a/.gitignore
+++ b/.gitignore
@@ -138,3 +138,4 @@ Makefile.local
 retroarch.js
 retroarch.js.mem
 *.bc
+*.wasm
diff --git a/Makefile.emscripten b/Makefile.emscripten
index 0334d2edf3..b1191efca4 100644
--- a/Makefile.emscripten
+++ b/Makefile.emscripten
@@ -25,7 +25,6 @@ HAVE_STATIC_VIDEO_FILTERS = 1
 HAVE_STATIC_AUDIO_FILTERS = 1
 MEMORY = 536870912
 
-# XXX: setting this to 1/2 currently crashes Firefox nightly
 PRECISE_F32 = 2
 
 ifneq ($(NATIVE_ZLIB),)
@@ -65,7 +64,7 @@ ifeq ($(DEBUG), 1)
    LDFLAGS += -O0 -g
    CFLAGS += -O0 -g
 else
-   LDFLAGS += -O2
+   LDFLAGS += -O2 -s WASM=1
    # WARNING: some optimizations can break some cores (ex: LTO breaks tyrquake)
    LDFLAGS += -s PRECISE_F32=$(PRECISE_F32)
    ifeq ($(LTO), 1)
@@ -74,7 +73,7 @@ else
    CFLAGS += -O2
 endif
 
-CFLAGS += -DHAVE_RPNG -Wall -Wno-unused-result -Wno-unused-variable -I. -Ilibretro-common/include -std=gnu99 -s USE_ZLIB=1 \
+CFLAGS += -DHAVE_RPNG -Wall -I. -Ilibretro-common/include -std=gnu99 -s USE_ZLIB=1 \
           -s EXPORTED_FUNCTIONS="['_main', '_malloc', '_cmd_savefiles', '_cmd_save_state', '_cmd_take_screenshot']"
 
 all: $(TARGET)

From 28b2bf537fb5f5e49b6ff7cc0c496d662ee41014 Mon Sep 17 00:00:00 2001
From: Toad King <toadking@toadking.com>
Date: Mon, 15 Jan 2018 04:17:01 -0600
Subject: [PATCH 15/18] fix warning

---
 frontend/drivers/platform_emscripten.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/frontend/drivers/platform_emscripten.c b/frontend/drivers/platform_emscripten.c
index 4982446275..4671638609 100644
--- a/frontend/drivers/platform_emscripten.c
+++ b/frontend/drivers/platform_emscripten.c
@@ -195,7 +195,6 @@ static void frontend_emscripten_get_env(int *argc, char *argv[],
 int main(int argc, char *argv[])
 {
    EMSCRIPTEN_RESULT r;
-   settings_t *settings = config_get_ptr();
 
    emscripten_set_canvas_element_size("#canvas", 800, 600);
    emscripten_set_element_css_size("#canvas", 800.0, 600.0);

From ccb45a068d4206e161845a8752984ec90c2197dd Mon Sep 17 00:00:00 2001
From: Toad King <toadking@toadking.com>
Date: Mon, 15 Jan 2018 04:52:35 -0600
Subject: [PATCH 16/18] fix compiler warning

---
 input/drivers/rwebinput_input.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/input/drivers/rwebinput_input.c b/input/drivers/rwebinput_input.c
index 8cdb425b5a..3108215bd1 100644
--- a/input/drivers/rwebinput_input.c
+++ b/input/drivers/rwebinput_input.c
@@ -567,7 +567,6 @@ static void rwebinput_input_free(void *data)
 static void rwebinput_process_keyboard_events(rwebinput_input_t *rwebinput,
    rwebinput_keyboard_event_t *event)
 {
-   uint32_t crc;
    uint32_t keycode;
    unsigned translated_keycode;
    uint32_t character = 0;

From 066a0a6b326e9696b48bcc20ef3f84efeb661c5c Mon Sep 17 00:00:00 2001
From: Toad King <toadking@toadking.com>
Date: Mon, 15 Jan 2018 04:53:27 -0600
Subject: [PATCH 17/18] put emscripten build artifacts into its own folder

clean up all artifacts on make clean
---
 Makefile.emscripten | 39 +++++++++++----------------------------
 1 file changed, 11 insertions(+), 28 deletions(-)

diff --git a/Makefile.emscripten b/Makefile.emscripten
index b1191efca4..3a95e9d979 100644
--- a/Makefile.emscripten
+++ b/Makefile.emscripten
@@ -27,6 +27,8 @@ MEMORY = 536870912
 
 PRECISE_F32 = 2
 
+OBJDIR := obj-emscripten
+
 ifneq ($(NATIVE_ZLIB),)
    WANT_ZLIB = 0
 endif
@@ -76,45 +78,26 @@ endif
 CFLAGS += -DHAVE_RPNG -Wall -I. -Ilibretro-common/include -std=gnu99 -s USE_ZLIB=1 \
           -s EXPORTED_FUNCTIONS="['_main', '_malloc', '_cmd_savefiles', '_cmd_save_state', '_cmd_take_screenshot']"
 
+RARCH_OBJ := $(addprefix $(OBJDIR)/,$(OBJ))
+
 all: $(TARGET)
 
-$(TARGET): $(OBJ)
+$(TARGET): $(RARCH_OBJ)
 	@$(if $(Q), $(shell echo echo LD $@),)
-	$(Q)$(LD) -o $@ $(OBJ) $(libretro) $(LIBS) $(LDFLAGS)
+	$(Q)$(LD) -o $@ $(RARCH_OBJ) $(libretro) $(LIBS) $(LDFLAGS)
 
-%.o: %.c
+$(OBJDIR)/%.o: %.c
+	@mkdir -p $(dir $@)
 	@$(if $(Q), $(shell echo echo CC $<),)
 	$(Q)$(CC) $(CFLAGS) $(DEFINES) $(EOPTS) -c -o $@ $<
 
-%.o: %.cpp
+$(OBJDIR)/%.o: %.cpp
+	@mkdir -p $(dir $@)
 	@$(if $(Q), $(shell echo echo CXX $<),)
 	$(Q)$(CXX) $(CXXFLAGS) $(DEFINES) $(EOPTS) -c -o $@ $<
 
 clean:
-	rm -f *.o
-	rm -f deps/libz/*.o
-	rm -f frontend/*.o
-	rm -f menu/*.o
-	rm -f menu/disp/*.o
-	rm -f audio/*.o
-	rm -f compat/*.o
-	rm -f compat/rxml/*.o
-	rm -f conf/*.o
-	rm -f gfx/scaler/*.o
-	rm -f gfx/*.o
-	rm -f gfx/d3d/*.o
-	rm -f gfx/drivers_context/*.o
-	rm -f gfx/math/*.o
-	rm -f gfx/drivers_font/*.o
-	rm -f gfx/drivers_font_renderer/*.o
-	rm -f gfx/py_state/*.o
-	rm -f gfx/rpng/*.o
-	rm -f gfx/glsym/*.o
-	rm -f record/*.o
-	rm -f input/*.o
-	rm -f tools/*.o
-	rm -f libretro-common/*/*.o
+	rm -rf $(OBJDIR)
 	rm -f $(TARGET)
-	rm -f *.d
 
 .PHONY: all clean

From bc511b8c8a56a8828ce5e2a90f3184ce08a03517 Mon Sep 17 00:00:00 2001
From: Toad King <toadking@toadking.com>
Date: Mon, 15 Jan 2018 04:53:44 -0600
Subject: [PATCH 18/18] enable shader pipeline

enables menu shader effects
---
 Makefile.emscripten | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Makefile.emscripten b/Makefile.emscripten
index 3a95e9d979..4ac23c1bf6 100644
--- a/Makefile.emscripten
+++ b/Makefile.emscripten
@@ -21,6 +21,7 @@ HAVE_SDL = 0
 HAVE_SDL2 = 0
 HAVE_ZLIB = 1
 WANT_ZLIB = 1
+HAVE_SHADERPIPELINE = 1
 HAVE_STATIC_VIDEO_FILTERS = 1
 HAVE_STATIC_AUDIO_FILTERS = 1
 MEMORY = 536870912