Implement AudioDeviceWASAPI

build/BUILD.gn

@@ -184,6 +184,7 @@ config("warnings") {
       "/wd4820",  # padding added after data member.
       "/wd5045",  # compiler will insert Spectre mitigation for memory load if
                   # switch specified.
+      "/wd4355",  # 'this': used in base member initializer list
 
       # TODO: Not sure how I feel about these conversion warnings.
       "/Wv:18",

src/engine/audio/BUILD.gn

@@ -21,7 +21,10 @@ source_set("audio") {
     ]
     libs += [ "asound" ]
   } else if (target_os == "win") {
-    sources += [ "audio_device_null.h" ]
+    sources += [
+      "audio_device_wasapi.cc",
+      "audio_device_wasapi.h",
+    ]
   } else if (target_os == "android") {
     sources += [
       "audio_device_oboe.cc",

src/engine/audio/audio_device_null.h

@@ -1,23 +0,0 @@
-#ifndef ENGINE_AUDIO_AUDIO_DEVICE_NULL_H
-#define ENGINE_AUDIO_AUDIO_DEVICE_NULL_H
-
-#include "engine/audio/audio_device.h"
-
-namespace eng {
-
-class AudioDeviceNull final : public AudioDevice {
- public:
-  AudioDeviceNull() = default;
-  ~AudioDeviceNull() final = default;
-
-  bool Initialize() final { return true; }
-
-  void Suspend() final {}
-  void Resume() final {}
-
-  size_t GetHardwareSampleRate() final { return 0; }
-};
-
-}  // namespace eng
-
-#endif  // ENGINE_AUDIO_AUDIO_DEVICE_NULL_H

src/engine/audio/audio_device_wasapi.cc

@@ -0,0 +1,210 @@
+#include "engine/audio/audio_device_wasapi.h"
+
+#include "base/log.h"
+
+const CLSID CLSID_MMDeviceEnumerator = __uuidof(MMDeviceEnumerator);
+const IID IID_IMMDeviceEnumerator = __uuidof(IMMDeviceEnumerator);
+const IID IID_IAudioClient = __uuidof(IAudioClient);
+const IID IID_IAudioRenderClient = __uuidof(IAudioRenderClient);
+
+using namespace base;
+
+namespace eng {
+
+AudioDeviceWASAPI::AudioDeviceWASAPI(AudioDevice::Delegate* delegate)
+    : delegate_(delegate) {}
+
+AudioDeviceWASAPI::~AudioDeviceWASAPI() {
+  LOG(0) << "Shutting down audio.";
+
+  TerminateAudioThread();
+
+  if (shutdown_event_)
+    CloseHandle(shutdown_event_);
+  if (ready_event_)
+    CloseHandle(ready_event_);
+  if (device_)
+    device_->Release();
+  if (audio_client_)
+    audio_client_->Release();
+  if (render_client_)
+    render_client_->Release();
+  if (device_enumerator_)
+    device_enumerator_->Release();
+}
+
+bool AudioDeviceWASAPI::Initialize() {
+  LOG(0) << "Initializing audio.";
+
+  HRESULT hr;
+  do {
+    hr = CoCreateInstance(CLSID_MMDeviceEnumerator, NULL, CLSCTX_ALL,
+                          IID_IMMDeviceEnumerator, (void**)&device_enumerator_);
+    if (FAILED(hr)) {
+      LOG(0) << "Unable to instantiate device enumerator: " << hr;
+      break;
+    }
+
+    hr = device_enumerator_->GetDefaultAudioEndpoint(eRender, eConsole,
+                                                     &device_);
+    if (FAILED(hr)) {
+      LOG(0) << "Unable to get default audio endpoint: " << hr;
+      break;
+    }
+
+    hr = device_->Activate(IID_IAudioClient, CLSCTX_ALL, NULL,
+                           (void**)&audio_client_);
+    if (FAILED(hr)) {
+      LOG(0) << "Unable to activate audio client: " << hr;
+      break;
+    }
+
+    // Use float format.
+    WAVEFORMATEX* closest_match = nullptr;
+    WAVEFORMATEXTENSIBLE wfxex = {0};
+    wfxex.Format.wFormatTag = WAVE_FORMAT_EXTENSIBLE;
+    wfxex.Format.cbSize = sizeof(WAVEFORMATEXTENSIBLE) - sizeof(WAVEFORMATEX);
+    wfxex.dwChannelMask = KSAUDIO_SPEAKER_STEREO;
+    wfxex.Format.nChannels = 2;
+    wfxex.Format.nSamplesPerSec = 48000;
+    wfxex.Format.wBitsPerSample = 32;
+    wfxex.Samples.wValidBitsPerSample = 32;
+    wfxex.Format.nBlockAlign =
+        wfxex.Format.nChannels * (wfxex.Format.wBitsPerSample >> 3);
+    wfxex.Format.nAvgBytesPerSec =
+        wfxex.Format.nBlockAlign * wfxex.Format.nSamplesPerSec;
+    wfxex.SubFormat = KSDATAFORMAT_SUBTYPE_IEEE_FLOAT;
+    hr = audio_client_->IsFormatSupported(AUDCLNT_SHAREMODE_SHARED,
+                                          &wfxex.Format, &closest_match);
+    if (FAILED(hr)) {
+      LOG(0) << "Unsupported sample format.";
+      break;
+    }
+
+    WAVEFORMATEX* format = closest_match ? closest_match : &wfxex.Format;
+    if ((format->wFormatTag != WAVE_FORMAT_IEEE_FLOAT &&
+         (format->wFormatTag != WAVE_FORMAT_EXTENSIBLE ||
+          reinterpret_cast<WAVEFORMATEXTENSIBLE*>(format)->SubFormat !=
+              KSDATAFORMAT_SUBTYPE_IEEE_FLOAT)) ||
+        format->nChannels != 2) {
+      LOG(0) << "Unsupported sample format.";
+      break;
+    }
+
+    sample_rate_ = format->nSamplesPerSec;
+
+    HRESULT hr = audio_client_->Initialize(
+        AUDCLNT_SHAREMODE_SHARED,
+        AUDCLNT_STREAMFLAGS_EVENTCALLBACK | AUDCLNT_STREAMFLAGS_NOPERSIST, 0, 0,
+        format, NULL);
+    if (closest_match)
+      CoTaskMemFree(closest_match);
+    if (FAILED(hr)) {
+      LOG(0) << "Unable to initialize audio client: " << hr;
+      break;
+    }
+
+    // Get the actual size of the allocated buffer.
+    hr = audio_client_->GetBufferSize(&buffer_size_);
+    if (FAILED(hr)) {
+      LOG(0) << "Unable to get audio client buffer size: " << hr;
+      break;
+    }
+
+    hr = audio_client_->GetService(IID_IAudioRenderClient,
+                                   (void**)&render_client_);
+    if (FAILED(hr)) {
+      LOG(0) << "Unable to get audio render client: " << hr;
+      break;
+    }
+
+    shutdown_event_ =
+        CreateEventEx(NULL, NULL, 0, EVENT_MODIFY_STATE | SYNCHRONIZE);
+    if (shutdown_event_ == NULL) {
+      LOG(0) << "Unable to create shutdown event: " << hr;
+      break;
+    }
+    ready_event_ =
+        CreateEventEx(NULL, NULL, 0, EVENT_MODIFY_STATE | SYNCHRONIZE);
+    if (ready_event_ == NULL) {
+      LOG(0) << "Unable to create samples ready event: " << hr;
+      break;
+    }
+
+    hr = audio_client_->SetEventHandle(ready_event_);
+    if (FAILED(hr)) {
+      LOG(0) << "Unable to set ready event: " << hr;
+      break;
+    }
+
+    StartAudioThread();
+
+    hr = audio_client_->Start();
+    if (FAILED(hr)) {
+      break;
+    }
+
+    return true;
+  } while (false);
+
+  return false;
+}
+
+void AudioDeviceWASAPI::Suspend() {
+  audio_client_->Stop();
+}
+
+void AudioDeviceWASAPI::Resume() {
+  audio_client_->Start();
+}
+
+size_t AudioDeviceWASAPI::GetHardwareSampleRate() {
+  return sample_rate_;
+}
+
+void AudioDeviceWASAPI::StartAudioThread() {
+  DCHECK(!audio_thread_.joinable());
+
+  LOG(0) << "Starting audio thread.";
+  audio_thread_ = std::thread(&AudioDeviceWASAPI::AudioThreadMain, this);
+}
+
+void AudioDeviceWASAPI::TerminateAudioThread() {
+  LOG(0) << "Terminating audio thread";
+  SetEvent(shutdown_event_);
+  audio_thread_.join();
+}
+
+void AudioDeviceWASAPI::AudioThreadMain() {
+  DCHECK(delegate_);
+
+  HANDLE wait_array[] = {shutdown_event_, ready_event_};
+
+  for (;;) {
+    switch (WaitForMultipleObjects(2, wait_array, FALSE, INFINITE)) {
+      case WAIT_OBJECT_0 + 0:  // shutdown_event_
+        return;
+
+      case WAIT_OBJECT_0 + 1: {  // ready_event_
+        UINT32 padding;
+        HRESULT hr = audio_client_->GetCurrentPadding(&padding);
+        if (SUCCEEDED(hr)) {
+          BYTE* pData;
+          UINT32 frames_available = buffer_size_ - padding;
+          hr = render_client_->GetBuffer(frames_available, &pData);
+          if (SUCCEEDED(hr)) {
+            delegate_->RenderAudio(reinterpret_cast<float*>(pData),
+                                   frames_available);
+            hr = render_client_->ReleaseBuffer(frames_available, 0);
+            if (!SUCCEEDED(hr))
+              DLOG(0) << "Unable to release buffer: " << hr;
+          } else {
+            DLOG(0) << "Unable to get buffer: " << hr;
+          }
+        }
+      } break;
+    }
+  }
+}
+
+}  // namespace eng

src/engine/audio/audio_device_wasapi.h

@@ -0,0 +1,49 @@
+#ifndef ENGINE_AUDIO_AUDIO_DEVICE_WASAPI_H
+#define ENGINE_AUDIO_AUDIO_DEVICE_WASAPI_H
+
+#include <thread>
+
+#include <AudioClient.h>
+#include <MMDeviceAPI.h>
+
+#include "engine/audio/audio_device.h"
+
+namespace eng {
+
+class AudioDeviceWASAPI final : public AudioDevice {
+ public:
+  AudioDeviceWASAPI(AudioDevice::Delegate* delegate);
+  ~AudioDeviceWASAPI() final;
+
+  bool Initialize() final;
+
+  void Suspend() final;
+  void Resume() final;
+
+  size_t GetHardwareSampleRate() final;
+
+ private:
+  IMMDevice* device_ = nullptr;
+  IAudioClient* audio_client_ = nullptr;
+  IAudioRenderClient* render_client_ = nullptr;
+  IMMDeviceEnumerator* device_enumerator_ = nullptr;
+
+  HANDLE shutdown_event_ = nullptr;
+  HANDLE ready_event_ = nullptr;
+
+  std::thread audio_thread_;
+
+  UINT32 buffer_size_ = 0;
+  size_t sample_rate_ = 0;
+
+  AudioDevice::Delegate* delegate_ = nullptr;
+
+  void StartAudioThread();
+  void TerminateAudioThread();
+
+  void AudioThreadMain();
+};
+
+}  // namespace eng
+
+#endif  // ENGINE_AUDIO_AUDIO_DEVICE_WASAPI_H

src/engine/audio/audio_mixer.cc

@@ -12,7 +12,7 @@
 #elif defined(__linux__)
 #include "engine/audio/audio_device_alsa.h"
 #elif defined(_WIN32)
-#include "engine/audio/audio_device_null.h"
+#include "engine/audio/audio_device_wasapi.h"
 #endif
 
 using namespace base;
@@ -26,8 +26,7 @@ AudioMixer::AudioMixer()
 #elif defined(__linux__)
       audio_device_{std::make_unique<AudioDeviceAlsa>(this)} {
 #elif defined(_WIN32)
-      // TODO: Implement AudioDeviceWindows
-      audio_device_{std::make_unique<AudioDeviceNull>()} {
+      audio_device_{std::make_unique<AudioDeviceWASAPI>(this)} {
 #endif
   bool res = audio_device_->Initialize();
   CHECK(res) << "Failed to initialize audio device.";

src/engine/platform/BUILD.gn

@@ -24,6 +24,7 @@ source_set("platform") {
     libs = [
       "gdi32.lib",  # Graphics
       "user32.lib",  # Win32 API core functionality.
+      "Ole32.lib",  # COM
       "opengl32.lib",
     ]
   } else if (target_os == "android") {

src/engine/platform/platform_win.cc

@@ -1,5 +1,7 @@
 #include "engine/platform/platform.h"
 
+#include <combaseapi.h>
+
 #include "base/log.h"
 #include "base/vecmath.h"
 #include "engine/input_event.h"
@@ -36,6 +38,9 @@ Platform::Platform(HINSTANCE instance, int cmd_show)
   LOG(0) << "Data path: " << data_path_.c_str();
   LOG(0) << "Shared data path: " << shared_data_path_.c_str();
 
+  HRESULT hr = CoInitializeEx(NULL, COINIT_APARTMENTTHREADED);
+  CHECK(SUCCEEDED(hr)) << "Unable to initialize COM: " << hr;
+
   WNDCLASSEXW wcex;
   wcex.cbSize = sizeof(WNDCLASSEX);
   wcex.style = CS_HREDRAW | CS_VREDRAW;