added option to select audio device (resolves #682)

Changes.txt

@@ -20,9 +20,9 @@
 
   * Extended global hotkeys for debug options.
 
-  * Added option to playback a game using the Time Machine
+  * Added option to playback a game using the Time Machine.
 
-  * Allow taking snapshots from within Time Machine dialog
+  * Allow taking snapshots from within Time Machine dialog.
 
   * Added ability to access most files that Stella uses from within a ZIP
     file. This includes the following:
@@ -33,7 +33,9 @@
     Basically, you are now able to put many files that Stella uses inside
     one ZIP file, and distribute just that file.
 
-  * Replaced "Re-disassemble" with "Disassemble @ current line" in debugger
+  * Added option to select the audio device.
+
+  * Replaced "Re-disassemble" with "Disassemble @ current line" in debugger.
 
   * Fix bug when taking fullscreen snapshots; the dimensions were sometimes
     cut off.

docs/index.html

@@ -2201,6 +2201,11 @@
     <td>Set the volume.</td>
   </tr>
 
+  <tr>
+    <td><pre>-audio.device &lt;number&gt;</pre></td>
+    <td>Set the audio device (0 = default).</td>
+  </tr>
+
   <tr>
     <td><pre>-audio.preset &lt;1 - 5&gt;</pre></td>
     <td>Set an audio preset. Numbers in sequence represent presets for
@@ -3084,7 +3089,8 @@
           <tr><th>Item</th><th>Brief description</th><th>For more information,<br>see <a href="#CommandLine">CommandLine</a></th></tr>
           <tr><td>Enable audio</td><td>Self-explanatory</td><td>-audio.enabled</td></tr>
           <tr><td>Volume</td><td>Self-explanatory</td><td>-audio.volume</td></tr>
-          <tr><td>Mode</td><td>Select an audio preset or choose 'custom' for manual configuration</td><td>-audio.preset</td></tr>
+          <tr><td>Device</td><td>Use the specified audio device.</td><td>-audio.device</td></tr>
+          <tr><td>Mode</td><td>Select an audio preset or choose 'Custom' for manual configuration.</td><td>-audio.preset</td></tr>
           <tr><td>Fragment size</td><td>The number of samples in a single fragment processed by the audio driver. Smaller values mean less latency, but may lead to dropouts (depending on OS and hardware).</td><td>-audio.fragment_size</td></tr>
           <tr><td>Sample rate</td><td>
             Output samples per second. Higher values reduce artifacts from resampling and decrease latency,
@@ -3097,7 +3103,7 @@
             some games (notably Quadrun).
           </td><td>-audio.resampling_quality</td></tr>
           <tr><td>Headroom</td><td>Number of frames to buffer before playback starts. Higher values increase latency, but reduce the potential for dropouts.</td><td>-audio.headroom</td></tr>
-          <tr><td>Buffer size</td><td>Maximum size of the audio buffer. Higher values increase maximum latency, but reduce the potential for dropouts</td><td>-audio.buffer_size</td></tr>
+          <tr><td>Buffer size</td><td>Maximum size of the audio buffer. Higher values increase maximum latency, but reduce the potential for dropouts.</td><td>-audio.buffer_size</td></tr>
       <tr><td>Stereo for all ROMs</td><td>Enable stereo mode for all ROMs.</td><td>-audio.stereo</td></tr>
           <tr><td>Pitfall II music pitch</td><td>Defines the pitch of Pitfall II music (which may vary between carts).</td><td>-audio.dpc_pitch</td></tr>
        </table>

src/common/AudioSettings.cxx

@@ -154,6 +154,12 @@ uInt32 AudioSettings::volume() const
   return lboundInt(mySettings.getInt(SETTING_VOLUME), 0);
 }
 
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+uInt32 AudioSettings::device() const
+{
+  return mySettings.getInt(SETTING_DEVICE);
+}
+
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 bool AudioSettings::enabled() const
 {
@@ -285,6 +291,14 @@ void AudioSettings::setVolume(uInt32 volume)
   normalize(mySettings);
 }
 
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void AudioSettings::setDevice(uInt32 device)
+{
+  if(!myIsPersistent) return;
+
+  mySettings.setValue(SETTING_DEVICE, device);
+}
+
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 void AudioSettings::setEnabled(bool isEnabled)
 {

src/common/AudioSettings.hxx

@@ -48,6 +48,7 @@ class AudioSettings
     static constexpr const char* SETTING_RESAMPLING_QUALITY  = "audio.resampling_quality";
     static constexpr const char* SETTING_STEREO              = "audio.stereo";
     static constexpr const char* SETTING_VOLUME              = "audio.volume";
+    static constexpr const char* SETTING_DEVICE              = "audio.device";
     static constexpr const char* SETTING_ENABLED             = "audio.enabled";
     static constexpr const char* SETTING_DPC_PITCH           = "audio.dpc_pitch";
 
@@ -59,6 +60,7 @@ class AudioSettings
     static constexpr ResamplingQuality DEFAULT_RESAMPLING_QUALITY   = ResamplingQuality::lanczos_2;
     static constexpr bool DEFAULT_STEREO                            = false;
     static constexpr uInt32 DEFAULT_VOLUME                          = 80;
+    static constexpr uInt32 DEFAULT_DEVICE                          = 0;
     static constexpr bool DEFAULT_ENABLED                           = true;
     static constexpr uInt32 DEFAULT_DPC_PITCH                       = 20000;
 
@@ -87,6 +89,8 @@ class AudioSettings
 
     uInt32 volume() const;
 
+    uInt32 device() const;
+
     bool enabled() const;
 
     uInt32 dpcPitch() const;
@@ -109,6 +113,8 @@ class AudioSettings
 
     void setVolume(uInt32 volume);
 
+    void setDevice(uInt32 device);
+
     void setEnabled(bool isEnabled);
 
     void setPersistent(bool isPersistent);

src/common/FrameBufferSDL2.cxx

@@ -118,7 +118,7 @@ void FrameBufferSDL2::queryHardware(vector<Common::Size>& fullscreenRes,
         Logger::debug(s.str());
         s.str("");
         lastRes = res.str();
-        s << lastRes << ": ";
+        s << "  " << lastRes << ": ";
       }
       s << mode.refresh_rate << "Hz";
       if(mode.w == display.w && mode.h == display.h && mode.refresh_rate == display.refresh_rate)

src/common/SoundNull.hxx

@@ -101,6 +101,13 @@ class SoundNull : public Sound
     */
     void adjustVolume(int direction = 1) override { }
 
+    /**
+      Sets the audio device.
+
+      @param device  The number of the device to select (0 = default).
+    */
+    void setDevice(uInt32 device) override { };
+
     /**
       This method is called to provide information about the sound device.
     */

src/common/SoundSDL2.cxx

@@ -56,6 +56,9 @@ SoundSDL2::SoundSDL2(OSystem& osystem, AudioSettings& audioSettings)
     return;
   }
 
+  queryHardware(myDevices);
+
+
   SDL_zero(myHardwareSpec);
   if(!openDevice())
     return;
@@ -76,6 +79,29 @@ SoundSDL2::~SoundSDL2()
   SDL_QuitSubSystem(SDL_INIT_AUDIO);
 }
 
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void SoundSDL2::queryHardware(VariantList& devices)
+{
+  ASSERT_MAIN_THREAD;
+
+  int numDevices = SDL_GetNumAudioDevices(0);
+
+  // log the available audio devices
+  ostringstream s;
+  s << "Supported audio devices (" << numDevices << "):";
+  Logger::debug(s.str());
+
+  VarList::push_back(devices, "Default", 0);
+  for(int i = 0; i < numDevices; ++i) {
+    ostringstream ss;
+
+    ss << "  " << i + 1 << ": " << SDL_GetAudioDeviceName(i, 0);
+    Logger::debug(ss.str());
+
+    VarList::push_back(devices, SDL_GetAudioDeviceName(i, 0), i + 1);
+  }
+}
+
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 bool SoundSDL2::openDevice()
 {
@@ -91,7 +117,11 @@ bool SoundSDL2::openDevice()
 
   if(myIsInitializedFlag)
     SDL_CloseAudioDevice(myDevice);
-  myDevice = SDL_OpenAudioDevice(nullptr, 0, &desired, &myHardwareSpec,
+
+  myDeviceId = BSPF::clamp(myAudioSettings.device(), 0u, uInt32(myDevices.size() - 1));
+  const char* device = myDeviceId ? myDevices.at(myDeviceId).first.c_str() : nullptr;
+
+  myDevice = SDL_OpenAudioDevice(device, 0, &desired, &myHardwareSpec,
                                  SDL_AUDIO_ALLOW_FREQUENCY_CHANGE);
 
   if(myDevice == 0)
@@ -126,7 +156,8 @@ void SoundSDL2::open(shared_ptr<AudioQueue> audioQueue,
   // Do we need to re-open the sound device?
   // Only do this when absolutely necessary
   if(myAudioSettings.sampleRate() != uInt32(myHardwareSpec.freq) ||
-     myAudioSettings.fragmentSize() != uInt32(myHardwareSpec.samples))
+     myAudioSettings.fragmentSize() != uInt32(myHardwareSpec.samples) ||
+     myAudioSettings.device() != myDeviceId)
     openDevice();
 
   myEmulationTiming = emulationTiming;
@@ -261,6 +292,7 @@ string SoundSDL2::about() const
   ostringstream buf;
   buf << "Sound enabled:"  << endl
       << "  Volume:   " << myVolume << "%" << endl
+      << "  Device:   " << myDevices.at(myDeviceId).first << endl
       << "  Channels: " << uInt32(myHardwareSpec.channels)
       << (myAudioQueue->isStereo() ? " (Stereo)" : " (Mono)") << endl
       << "  Preset:   ";

src/common/SoundSDL2.hxx

@@ -108,6 +108,13 @@ class SoundSDL2 : public Sound
     string about() const override;
 
   protected:
+    /**
+      This method is called to query the audio devices.
+
+      @param devices  List of device names
+    */
+    void queryHardware(VariantList& devices);
+
     /**
       Invoked by the sound callback to process the next sound fragment.
       The stream is 16-bits (even though the callback is 8-bits), since
@@ -139,6 +146,8 @@ class SoundSDL2 : public Sound
     // Audio specification structure
     SDL_AudioSpec myHardwareSpec;
 
+    uInt32 myDeviceId{0};
+
     SDL_AudioDeviceID myDevice{0};
 
     shared_ptr<AudioQueue> myAudioQueue;

src/emucore/Settings.cxx

@@ -80,6 +80,7 @@ Settings::Settings()
   // Sound options
   setPermanent(AudioSettings::SETTING_ENABLED, AudioSettings::DEFAULT_ENABLED);
   setPermanent(AudioSettings::SETTING_VOLUME, AudioSettings::DEFAULT_VOLUME);
+  setPermanent(AudioSettings::SETTING_DEVICE, AudioSettings::DEFAULT_DEVICE);
   setPermanent(AudioSettings::SETTING_PRESET, static_cast<int>(AudioSettings::DEFAULT_PRESET));
   setPermanent(AudioSettings::SETTING_FRAGMENT_SIZE, AudioSettings::DEFAULT_FRAGMENT_SIZE);
   setPermanent(AudioSettings::SETTING_SAMPLE_RATE, AudioSettings::DEFAULT_SAMPLE_RATE);
@@ -426,6 +427,7 @@ void Settings::usage() const
   #ifdef SOUND_SUPPORT
     << "  -audio.enabled            <1|0>      Enable audio\n"
     << "  -audio.volume             <0-100>    Volume\n"
+    << "  -audio.device             <number>   ID of the audio device (0 = default)\n"
     << "  -audio.preset             <1-5>      Audio preset (or 1 for custom)\n"
     << "  -audio.sample_rate        <number>   Output sample rate (44100|48000|96000)\n"
     << "  -audio.fragment_size      <number>   Fragment size (128|256|512|1024|\n"

src/emucore/Sound.hxx

@@ -97,10 +97,28 @@ class Sound
     */
     virtual string about() const = 0;
 
+    /**
+      Get the supported devices for the audio hardware.
+
+      @return  An array of supported devices
+    */
+    const VariantList& supportedDevices() const {return myDevices;}
+
+  protected:
+    /**
+      This method is called to query the audio devices.
+
+      @param devices  List of device names
+    */
+    virtual void queryHardware(VariantList& devices) = 0;
+
   protected:
     // The OSystem for this sound object
     OSystem& myOSystem;
 
+    // Supported device
+    VariantList myDevices;
+
   private:
     // Following constructors and assignment operators not supported
     Sound() = delete;

src/gui/VideoAudioDialog.cxx

@@ -68,7 +68,7 @@ VideoAudioDialog::VideoAudioDialog(OSystem& osystem, DialogContainer& parent,
 
   // Set real dimensions
   setSize(44 * fontWidth + HBORDER * 2 + PopUpWidget::dropDownWidth(font) * 2,
-          _th + VGAP * 6 + lineHeight + 10 * (lineHeight + VGAP) + buttonHeight + VBORDER * 3,
+          _th + VGAP * 3 + lineHeight + 11 * (lineHeight + VGAP) + buttonHeight + VBORDER * 3,
           max_w, max_h);
 
   // The tab widget
@@ -365,6 +365,14 @@ void VideoAudioDialog::addAudioTab()
   wid.push_back(myVolumeSlider);
   ypos += lineHeight + VGAP;
 
+  // Device
+  myDevicePopup = new PopUpWidget(myTab, _font, xpos, ypos,
+                                  _w - xpos - lwidth - HBORDER - PopUpWidget::dropDownWidth(_font) - 2, lineHeight,
+                                  instance().sound().supportedDevices(),
+                                  "Device", lwidth, kDeviceChanged);
+  wid.push_back(myDevicePopup);
+  ypos += lineHeight + VGAP;
+
   // Mode
   items.clear();
   VarList::push_back(items, "Low quality, medium lag", static_cast<int>(AudioSettings::Preset::lowQualityMediumLag));
@@ -542,6 +550,11 @@ void VideoAudioDialog::loadConfig()
   // Volume
   myVolumeSlider->setValue(audioSettings.volume());
 
+  // Device
+  uInt32 deviceId = BSPF::clamp(audioSettings.device(), 0u,
+                                uInt32(instance().sound().supportedDevices().size() - 1));
+  myDevicePopup->setSelected(deviceId);
+
   // Stereo
   myStereoSoundCheckbox->setState(audioSettings.stereo());
 
@@ -666,6 +679,9 @@ void VideoAudioDialog::saveConfig()
   audioSettings.setVolume(myVolumeSlider->getValue());
   instance().sound().setVolume(myVolumeSlider->getValue());
 
+  // Device
+  audioSettings.setDevice(myDevicePopup->getSelected());
+
   // Stereo
   audioSettings.setStereo(myStereoSoundCheckbox->getState());
 
@@ -754,6 +770,7 @@ void VideoAudioDialog::setDefaults()
     case 3:  // Audio
       mySoundEnableCheckbox->setState(AudioSettings::DEFAULT_ENABLED);
       myVolumeSlider->setValue(AudioSettings::DEFAULT_VOLUME);
+      myDevicePopup->setSelected(AudioSettings::DEFAULT_DEVICE);
       myStereoSoundCheckbox->setState(AudioSettings::DEFAULT_STEREO);
       myDpcPitch->setValue(AudioSettings::DEFAULT_DPC_PITCH);
       myModePopup->setSelected(static_cast<int>(AudioSettings::DEFAULT_PRESET));
@@ -1061,6 +1078,7 @@ void VideoAudioDialog::updateEnabledState()
   bool userMode = preset == AudioSettings::Preset::custom;
 
   myVolumeSlider->setEnabled(active);
+  myDevicePopup->setEnabled(active);
   myStereoSoundCheckbox->setEnabled(active);
   myModePopup->setEnabled(active);
   // enable only for Pitfall II cart

src/gui/VideoAudioDialog.hxx

@@ -115,6 +115,7 @@ class VideoAudioDialog : public Dialog
     // Audio
     CheckboxWidget*   mySoundEnableCheckbox{nullptr};
     SliderWidget*     myVolumeSlider{nullptr};
+    PopUpWidget*      myDevicePopup{nullptr};
     CheckboxWidget*   myStereoSoundCheckbox{nullptr};
     PopUpWidget*      myModePopup{nullptr};
     PopUpWidget*      myFragsizePopup{nullptr};
@@ -149,6 +150,7 @@ class VideoAudioDialog : public Dialog
       kScanlinesChanged   = 'VDsc',
 
       kSoundEnableChanged = 'ADse',
+      kDeviceChanged      = 'ADdc',
       kModeChanged        = 'ADmc',
       kHeadroomChanged    = 'ADhc',
       kBufferSizeChanged  = 'ADbc'