add an option to select audio device

src/audio/abstract.cpp

@@ -26,6 +26,10 @@ bool TAAudio::setRun(bool run) {
   return running;
 }
 
+std::vector<String> TAAudio::listAudioDevices() {
+  return std::vector<String>();
+}
+
 bool TAAudio::init(TAAudioDesc& request, TAAudioDesc& response) {
   response=request;
   return true;

src/audio/sdl.cpp

@@ -1,4 +1,6 @@
+#include <SDL_audio.h>
 #include <string.h>
+#include <vector>
 #include "../ta-log.h"
 #include "sdl.h"
 
@@ -49,14 +51,40 @@ bool TAAudioSDL::setRun(bool run) {
   return running;
 }
 
+std::vector<String> TAAudioSDL::listAudioDevices() {
+  std::vector<String> ret;
+  if (!audioSysStarted) {
+    if (SDL_Init(SDL_INIT_AUDIO)<0) {
+      logE("could not initialize SDL to list audio devices\n");
+    } else {
+      audioSysStarted=true;
+    }
+  }
+
+  int count=SDL_GetNumAudioDevices(false);
+  if (count<0) return ret;
+
+  for (int i=0; i<count; i++) {
+    const char* devName=SDL_GetAudioDeviceName(i,false);
+    if (devName!=NULL) {
+      ret.push_back(String(devName));
+    }
+  }
+
+  return ret;
+}
+
 bool TAAudioSDL::init(TAAudioDesc& request, TAAudioDesc& response) {
   if (initialized) {
     logE("audio already initialized\n");
     return false;
   }
-  if (SDL_Init(SDL_INIT_AUDIO)<0) {
-    logE("could not initialize SDL\n");
-    return false;
+  if (!audioSysStarted) {
+    if (SDL_Init(SDL_INIT_AUDIO)<0) {
+      logE("could not initialize SDL\n");
+      return false;
+    }
+    audioSysStarted=true;
   }
 
   desc=request;
@@ -69,12 +97,13 @@ bool TAAudioSDL::init(TAAudioDesc& request, TAAudioDesc& response) {
   ac.callback=taSDLProcess;
   ac.userdata=this;
 
-  ai=SDL_OpenAudioDevice(NULL,0,&ac,&ar,SDL_AUDIO_ALLOW_FREQUENCY_CHANGE);
+  ai=SDL_OpenAudioDevice(request.deviceName.empty()?NULL:request.deviceName.c_str(),0,&ac,&ar,SDL_AUDIO_ALLOW_FREQUENCY_CHANGE);
   if (ai==0) {
     logE("could not open audio device: %s\n",SDL_GetError());
     return false;
   }
 
+  desc.deviceName=request.deviceName;
   desc.name="";
   desc.rate=ar.freq;
   desc.inChans=0;

src/audio/sdl.h

@@ -4,6 +4,7 @@
 class TAAudioSDL: public TAAudio {
   SDL_AudioSpec ac, ar;
   SDL_AudioDeviceID ai;
+  bool audioSysStarted;
 
   public:
     void onProcess(unsigned char* buf, int nframes);
@@ -11,5 +12,8 @@ class TAAudioSDL: public TAAudio {
     void* getContext();
     bool quit();
     bool setRun(bool run);
+    std::vector<String> listAudioDevices();
     bool init(TAAudioDesc& request, TAAudioDesc& response);
+    TAAudioSDL():
+      audioSysStarted(false) {}
 };

src/audio/taAudio.h

@@ -31,7 +31,7 @@ enum TAAudioFormat {
 };
 
 struct TAAudioDesc {
-  String name;
+  String name, deviceName;
   double rate;
   unsigned int bufsize, fragments;
   unsigned char inChans, outChans;
@@ -46,40 +46,6 @@ struct TAAudioDesc {
     outFormat(TA_AUDIO_FORMAT_F32) {}
 };
 
-class TAAudio {
-  protected:
-    TAAudioDesc desc;
-    TAAudioFormat outFormat;
-    bool running, initialized;
-    float** inBufs;
-    float** outBufs;
-    void (*audioProcCallback)(void*,float**,float**,int,int,unsigned int);
-    void* audioProcCallbackUser;
-    void (*sampleRateChanged)(SampleRateChangeEvent);
-    void (*bufferSizeChanged)(BufferSizeChangeEvent);
-  public:
-    void setSampleRateChangeCallback(void (*callback)(SampleRateChangeEvent));
-    void setBufferSizeChangeCallback(void (*callback)(BufferSizeChangeEvent));
-
-    void setCallback(void (*callback)(void*,float**,float**,int,int,unsigned int), void* user);
-
-    virtual void* getContext();
-    virtual bool quit();
-    virtual bool setRun(bool run);
-    virtual bool init(TAAudioDesc& request, TAAudioDesc& response);
-
-    TAAudio():
-      outFormat(TA_AUDIO_FORMAT_F32),
-      running(false),
-      initialized(false),
-      inBufs(NULL),
-      outBufs(NULL),
-      audioProcCallback(NULL),
-      sampleRateChanged(NULL),
-      bufferSizeChanged(NULL) {}
-
-    virtual ~TAAudio();
-};
 
 enum TAMidiMessageTypes {
   TA_MIDI_NOTE_OFF=0x80,
@@ -146,7 +112,42 @@ class TAMidiOut {
 class TAMidi {
   std::vector<TAMidiIn*> in;
   std::vector<TAMidiOut*> out;
+};
 
+class TAAudio {
+  protected:
+    TAAudioDesc desc;
+    TAAudioFormat outFormat;
+    bool running, initialized;
+    float** inBufs;
+    float** outBufs;
+    void (*audioProcCallback)(void*,float**,float**,int,int,unsigned int);
+    void* audioProcCallbackUser;
+    void (*sampleRateChanged)(SampleRateChangeEvent);
+    void (*bufferSizeChanged)(BufferSizeChangeEvent);
+  public:
+    TAMidi* midi;
+    void setSampleRateChangeCallback(void (*callback)(SampleRateChangeEvent));
+    void setBufferSizeChangeCallback(void (*callback)(BufferSizeChangeEvent));
 
+    void setCallback(void (*callback)(void*,float**,float**,int,int,unsigned int), void* user);
+
+    virtual void* getContext();
+    virtual bool quit();
+    virtual bool setRun(bool run);
+    virtual std::vector<String> listAudioDevices();
+    virtual bool init(TAAudioDesc& request, TAAudioDesc& response);
+
+    TAAudio():
+      outFormat(TA_AUDIO_FORMAT_F32),
+      running(false),
+      initialized(false),
+      inBufs(NULL),
+      outBufs(NULL),
+      audioProcCallback(NULL),
+      sampleRateChanged(NULL),
+      bufferSizeChanged(NULL) {}
+
+    virtual ~TAAudio();
 };
 #endif

src/engine/engine.cpp

@@ -6181,6 +6181,17 @@ TAAudioDesc& DivEngine::getAudioDescGot() {
   return got;
 }
 
+std::vector<String>& DivEngine::getAudioDevices() {
+  return audioDevs;
+}
+
+void DivEngine::rescanAudioDevices() {
+  audioDevs.clear();
+  if (output!=NULL) {
+    audioDevs=output->listAudioDevices();
+  }
+}
+
 void DivEngine::initDispatch() {
   isBusy.lock();
   for (int i=0; i<song.systemLen; i++) {
@@ -6285,6 +6296,10 @@ bool DivEngine::initAudioBackend() {
       logE("invalid audio engine!\n");
       return false;
   }
+
+  audioDevs=output->listAudioDevices();
+
+  want.deviceName=getConfString("audioDevice","");
   want.bufsize=getConfInt("audioBufSize",1024);
   want.rate=getConfInt("audioRate",44100);
   want.fragments=2;

src/engine/engine.h

@@ -169,6 +169,7 @@ class DivEngine {
   String configFile;
   String lastError;
   String warnings;
+  std::vector<String> audioDevs;
 
   struct SamplePreview {
     int sample;
@@ -505,6 +506,12 @@ class DivEngine {
     // set the view mode.
     void setView(DivStatusView which);
 
+    // get available audio devices
+    std::vector<String>& getAudioDevices();
+
+    // rescan audio devices
+    void rescanAudioDevices();
+
     // set the console mode.
     void setConsoleMode(bool enable);
     

src/gui/gui.cpp

@@ -3769,6 +3769,21 @@ void FurnaceGUI::drawSettings() {
         ImGui::SameLine();
         ImGui::Combo("##Backend",&settings.audioEngine,audioBackends,2);
 
+        ImGui::Text("Device");
+        ImGui::SameLine();
+        String audioDevName=settings.audioDevice.empty()?"<System default>":settings.audioDevice;
+        if (ImGui::BeginCombo("##AudioDevice",audioDevName.c_str())) {
+          if (ImGui::Selectable("<System default>",settings.audioDevice.empty())) {
+            settings.audioDevice="";
+          }
+          for (String& i: e->getAudioDevices()) {
+            if (ImGui::Selectable(i.c_str(),i==settings.audioDevice)) {
+              settings.audioDevice=i;
+            }
+          }
+          ImGui::EndCombo();
+        }
+
         ImGui::Text("Sample rate");
         ImGui::SameLine();
         String sr=fmt::sprintf("%d",settings.audioRate);
@@ -4225,6 +4240,7 @@ void FurnaceGUI::syncSettings() {
   settings.patFontSize=e->getConfInt("patFontSize",18);
   settings.iconSize=e->getConfInt("iconSize",16);
   settings.audioEngine=(e->getConfString("audioEngine","SDL")=="SDL")?1:0;
+  settings.audioDevice=e->getConfString("audioDevice","");
   settings.audioQuality=e->getConfInt("audioQuality",0);
   settings.audioBufSize=e->getConfInt("audioBufSize",1024);
   settings.audioRate=e->getConfInt("audioRate",44100);
@@ -4414,6 +4430,7 @@ void FurnaceGUI::commitSettings() {
   e->setConf("patFontSize",settings.patFontSize);
   e->setConf("iconSize",settings.iconSize);
   e->setConf("audioEngine",String(audioBackends[settings.audioEngine]));
+  e->setConf("audioDevice",settings.audioDevice);
   e->setConf("audioQuality",settings.audioQuality);
   e->setConf("audioBufSize",settings.audioBufSize);
   e->setConf("audioRate",settings.audioRate);

src/gui/gui.h

@@ -408,6 +408,7 @@ class FurnaceGUI {
     unsigned int maxUndoSteps;
     String mainFontPath;
     String patFontPath;
+    String audioDevice;
 
     Settings():
       mainFontSize(18),
@@ -443,7 +444,8 @@ class FurnaceGUI {
       restartOnFlagChange(1),
       maxUndoSteps(100),
       mainFontPath(""),
-      patFontPath("") {}
+      patFontPath(""),
+      audioDevice("") {}
   } settings;
 
   char finalLayoutPath[4096];