Connected volume control GUI with Controller class, and made slider non-linear.

This should be reviewed, and a better algorith should be selected.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@17375 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/apps/mediaplayer/Controller.cpp

@@ -60,6 +60,7 @@ Controller::Controller()
  ,	fVideoPlayThread(-1)
  ,	fStopAudioPlayback(false)
  ,	fStopVideoPlayback(false)
+ ,	fSoundOutput(NULL)
 {
 }
 
@@ -251,6 +252,14 @@ Controller::VolumeDown()
 }
 
 
+void
+Controller::SetVolume(float value)
+{
+	if (fSoundOutput) // hack...
+		fSoundOutput->SetVolume(value);
+}
+
+
 bool
 Controller::IsOverlayActive()
 {
@@ -349,8 +358,9 @@ Controller::AudioPlayThread()
 	media_format fmt;
 	fmt.type = B_MEDIA_RAW_AUDIO;
 	fmt.u.raw_audio = media_multi_audio_format::wildcard;
+#ifdef __HAIKU__
 	fmt.u.raw_audio.format = media_multi_audio_format::B_AUDIO_FLOAT;
-
+#endif
 	fAudioTrack->DecodedFormat(&fmt);
 	
 	SoundOutput out(fName.String(), fmt.u.raw_audio);
@@ -360,9 +370,11 @@ Controller::AudioPlayThread()
 	int64 frames;
 	media_header mh;
 	
+	fSoundOutput = &out;
 	while (!fStopAudioPlayback && B_OK == fAudioTrack->ReadFrames(buffer, &frames, &mh)) {
 		out.Play(buffer, frames * frame_size);
 	}
+	fSoundOutput = NULL;
 }
 
 

src/apps/mediaplayer/Controller.h

@@ -27,6 +27,7 @@
 class BBitmap;
 class BMediaFile;
 class BMediaTrack;
+class SoundOutput;
 class VideoView;
 
 class Controller
@@ -63,6 +64,8 @@ public:
 	
 	void					VolumeUp();
 	void					VolumeDown();
+	
+	void					SetVolume(float value);
 
 private:
 	static int32			audio_play_thread(void *self);
@@ -95,6 +98,7 @@ private:
 	thread_id				fVideoPlayThread;
 	volatile bool			fStopAudioPlayback;
 	volatile bool			fStopVideoPlayback;
+	SoundOutput	*			fSoundOutput;
 };
 
 

src/apps/mediaplayer/ControllerView.cpp

@@ -135,8 +135,8 @@ ControllerView::SkipForward()
 void
 ControllerView::SetVolume(float value)
 {
-	printf("ControllerView::SetVolume(%.2f)\n", value);
-	// 0.0 ... 1.0
+	printf("ControllerView::SetVolume(%.4f)\n", value);
+	fController->SetVolume(value);
 }
 
 

src/apps/mediaplayer/TransportControlGroup.cpp

@@ -40,8 +40,15 @@ enum {
 #define VOLUME_MIN_WIDTH 70.0
 #define VOLUME_SLIDER_LAYOUT_WEIGHT 2.0
 
-#define kMaxVolume 1024
-#define kMaxSeekPos 65535
+// the range of the volume sliders (in dB)
+#define kVolumeDbMax	6.0
+#define kVolumeDbMin	-60.0
+// a power function for non linear sliders
+#define kVolumeDbExpPositive 1.4	// for dB values > 0
+#define kVolumeDbExpNegative 1.9	// for dB values < 0
+
+#define kVolumeFactor	1000
+#define kPositionFactor	65535
 
 // constructor
 TransportControlGroup::TransportControlGroup(BRect frame)
@@ -57,7 +64,7 @@ TransportControlGroup::TransportControlGroup(BRect frame)
     // Seek Slider
 	fSeekSlider = new SeekSlider(frame, "seek slider",
 								 new BMessage(MSG_SEEK),
-								 0, kMaxSeekPos);
+								 0, kPositionFactor);
 	fSeekSlider->ResizeToPreferred();
 	AddChild(fSeekSlider);
 
@@ -142,9 +149,11 @@ TransportControlGroup::TransportControlGroup(BRect frame)
     // Volume Slider
 	fVolumeSlider = new VolumeSlider(BRect(0.0, 0.0, VOLUME_MIN_WIDTH,
 										   kVolumeSliderBitmapHeight - 1.0),
-									 "volume slider", 0, kMaxVolume,
+									 "volume slider", 
+									 _DbToGain(_ExponentialToLinear(kVolumeDbMin)) * kVolumeFactor, 
+									 _DbToGain(_ExponentialToLinear(kVolumeDbMax)) * kVolumeFactor,
 									 new BMessage(MSG_SET_VOLUME));
-	fVolumeSlider->SetValue(128);
+	fVolumeSlider->SetValue(_DbToGain(_ExponentialToLinear(0.0)) * kVolumeFactor);
 	AddChild(fVolumeSlider);
 }
 
@@ -252,6 +261,59 @@ void TransportControlGroup::SetVolume(float value)		{}
 void TransportControlGroup::ToggleMute()				{}
 void TransportControlGroup::SetPosition(float value)	{}
 
+// #pragma mark -
+
+
+float
+TransportControlGroup::_LinearToExponential(float db_in)
+{
+	float db = db_in;
+	if (db >= 0) {
+		db = db * (pow(fabs(kVolumeDbMax), (1.0 / kVolumeDbExpPositive)) / fabs(kVolumeDbMax));
+		db = pow(db, kVolumeDbExpPositive);
+	} else {
+		db = -db;
+		db = db * (pow(fabs(kVolumeDbMin), (1.0 / kVolumeDbExpNegative)) / fabs(kVolumeDbMin));
+		db = pow(db, kVolumeDbExpNegative);
+		db = -db;
+	}
+	printf("_LinearToExponential %.4f => %.4f\n", db_in, db);
+	return db;
+}
+
+
+float
+TransportControlGroup::_ExponentialToLinear(float db_in)
+{
+	float db = db_in;
+	if (db >= 0) {
+		db = pow(db, (1.0 / kVolumeDbExpPositive));
+		db = db * (fabs(kVolumeDbMax) / pow(fabs(kVolumeDbMax), (1.0 / kVolumeDbExpPositive)));
+	} else {
+		db = -db;
+		db = pow(db, (1.0 / kVolumeDbExpNegative));
+		db = db * (fabs(kVolumeDbMin) / pow(fabs(kVolumeDbMin), (1.0 / kVolumeDbExpNegative)));
+		db = -db;
+	}
+	printf("_ExponentialToLinear %.4f => %.4f\n", db_in, db);
+	return db;
+}
+
+
+float
+TransportControlGroup::_DbToGain(float db)
+{
+	return pow(10.0, db / 20.0);
+}
+
+
+float
+TransportControlGroup::_GainToDb(float gain)
+{
+	return 20.0 * log10(gain);
+}
+
+
 // #pragma mark -
 
 // SetEnabled
@@ -316,12 +378,6 @@ TransportControlGroup::SetMuted(bool mute)
 	fVolumeSlider->SetMuted(mute);
 }
 
-// Volume
-uint32
-TransportControlGroup::Volume() const
-{
-	return fVolumeSlider->Value();
-}
 
 // #pragma mark -
 
@@ -473,7 +529,11 @@ TransportControlGroup::_SkipForward()
 void
 TransportControlGroup::_SetVolume()
 {
-	SetVolume((float)(fVolumeSlider->Value() / 255.0));
+	float pos = fVolumeSlider->Value() / (float)kVolumeFactor;
+	float db = _ExponentialToLinear(_GainToDb(pos));
+	float gain = _DbToGain(db);
+	printf("_SetVolume: pos %.4f, db %.4f, gain %.4f\n", pos, db, gain);
+	SetVolume(gain);
 }
 
 // _ToggleMute
@@ -488,7 +548,7 @@ TransportControlGroup::_ToggleMute()
 void
 TransportControlGroup::_UpdatePosition()
 {
-	SetPosition((float)(fSeekSlider->Value() / (float)kMaxSeekPos));
+	SetPosition(fSeekSlider->Value() / (float)kPositionFactor);
 }
 
 

src/apps/mediaplayer/TransportControlGroup.h

@@ -67,7 +67,6 @@ class TransportControlGroup : public BView {
 
 			void				SetAudioEnabled(bool enable);
 			void				SetMuted(bool mute);
-			uint32				Volume() const;
 
  private:
 			void				_LayoutControls(BRect frame) const;
@@ -87,6 +86,11 @@ class TransportControlGroup : public BView {
 			void				_ToggleMute();
 			void				_UpdatePosition();
 
+			float				_LinearToExponential(float db);
+			float				_ExponentialToLinear(float db);
+			float				_DbToGain(float db);
+			float				_GainToDb(float gain);
+
 			SeekSlider*			fSeekSlider;
 
 			VolumeSlider*		fVolumeSlider;