support MIDI control faders in headless build (#483)

ChangeLog

@@ -13,10 +13,11 @@
 
 - improve server audio mix processing for better clipping behavior
 
+- support MIDI control faders in headless build (#483)
+
 - bug fix: --showallservers ping column sort is alphabetic (#201)
 
 
-TODO If network configuration of client changes (e.g. Wifi to LAN) we may get audio issues for a period of time #426
 
 
 

src/audiomixerboard.cpp

@@ -470,7 +470,7 @@ void CChannelFader::SendFaderLevelToServer ( const double dLevel,
                                           ( !bOtherChannelIsSolo || IsSolo() ) );
 
     // emit signal for new fader gain value
-    emit gainValueChanged ( CalcFaderGain ( dLevel ),
+    emit gainValueChanged ( MathUtils::CalcFaderGain ( dLevel ),
                             bIsMyOwnFader,
                             bIsGroupUpdate,
                             bSuppressServerUpdate,
@@ -569,7 +569,7 @@ void CChannelFader::SetMute ( const bool bState )
         if ( !bOtherChannelIsSolo || IsSolo() )
         {
             // mute was unchecked, get current fader value and apply
-            emit gainValueChanged ( CalcFaderGain ( GetFaderLevel() ), bIsMyOwnFader, false, false, -1 ); // set level ratio to in invalid value
+            emit gainValueChanged ( MathUtils::CalcFaderGain ( GetFaderLevel() ), bIsMyOwnFader, false, false, -1 ); // set level ratio to in invalid value
         }
     }
 }
@@ -771,23 +771,6 @@ void CChannelFader::SetChannelInfos ( const CChannelInfo& cChanInfo )
     plblLabel->setToolTip       ( strToolTip );
 }
 
-double CChannelFader::CalcFaderGain ( const double dValue )
-{
-    // convert actual slider range in gain values
-    // and normalize so that maximum gain is 1
-    const double dInValueRange0_1 = dValue / AUD_MIX_FADER_MAX;
-
-    // map range from 0..1 to range -35..0 dB and calculate linear gain
-    if ( dValue == 0 )
-    {
-        return 0; // -infinity
-    }
-    else
-    {
-        return pow ( 10, ( dInValueRange0_1 * 35 - 35 ) / 20 );
-    }
-}
-
 
 /******************************************************************************\
 * CAudioMixerBoard                                                             *

src/audiomixerboard.h

@@ -84,7 +84,6 @@ public:
 
 protected:
     void   UpdateGroupIDDependencies();
-    double CalcFaderGain ( const double dValue );
     void   SetMute ( const bool bState );
     void   SetupFaderTag ( const ESkillLevel eSkillLevel );
     void   SendPanValueToServer ( const int iPan );

src/client.cpp

@@ -182,7 +182,7 @@ CClient::CClient ( const quint16  iPortNumber,
         this, &CClient::OnSndCrdReinitRequest );
 
     QObject::connect ( &Sound, &CSound::ControllerInFaderLevel,
-        this, &CClient::ControllerInFaderLevel );
+        this, &CClient::OnControllerInFaderLevel );
 
     QObject::connect ( &Socket, &CHighPrioSocket::InvalidPacketReceived,
         this, &CClient::OnInvalidPacketReceived );
@@ -684,6 +684,22 @@ void CClient::OnHandledSignal ( int sigNum )
 #endif
 }
 
+void CClient::OnControllerInFaderLevel ( int iChannelIdx,
+                                         int iValue )
+{
+    // in case of a headless client the faders cannot be moved so we need
+    // to send the controller information directly to the server
+#ifdef HEADLESS
+    // only apply new fader level if channel index is valid
+    if ( ( iChannelIdx >= 0 ) && ( iChannelIdx < MAX_NUM_CHANNELS ) )
+    {
+        SetRemoteChanGain ( iChannelIdx, MathUtils::CalcFaderGain ( iValue ), false );
+    }
+#endif
+
+    emit ControllerInFaderLevel ( iChannelIdx, iValue );
+}
+
 void CClient::Start()
 {
     // init object

src/client.h

@@ -245,7 +245,7 @@ public:
 
     void SetRemoteChanGain ( const int iId, const double dGain, const bool bIsMyOwnFader );
 
-	void SetRemoteChanPan ( const int iId, const double dPan )
+    void SetRemoteChanPan ( const int iId, const double dPan )
         { Channel.SetRemoteChanPan ( iId, dPan ); }
 
     void SetRemoteInfo() { Channel.SetRemoteInfo ( ChannelInfo ); }
@@ -372,7 +372,7 @@ protected:
 
     CSignalHandler*         pSignalHandler;
 
-public slots:
+protected slots:
     void OnHandledSignal ( int sigNum );
     void OnSendProtMessage ( CVector<uint8_t> vecMessage );
     void OnInvalidPacketReceived ( CHostAddress RecHostAddr );
@@ -397,6 +397,7 @@ public slots:
                                           int          iNumClients );
 
     void OnSndCrdReinitRequest ( int iSndCrdResetType );
+    void OnControllerInFaderLevel ( int iChannelIdx, int iValue );
 
 signals:
     void ConClientListMesReceived ( CVector<CChannelInfo> vecChanInfo );

src/util.h

@@ -1278,6 +1278,24 @@ public:
     {
         return bXFade ? dPan : std::min ( 0.5, dPan ) * 2;
     }
+
+    // calculate linear gain from fader values which are in dB
+    static double CalcFaderGain ( const double dValue )
+    {
+        // convert actual slider range in gain values
+        // and normalize so that maximum gain is 1
+        const double dInValueRange0_1 = dValue / AUD_MIX_FADER_MAX;
+
+        // map range from 0..1 to range -35..0 dB and calculate linear gain
+        if ( dValue == 0 )
+        {
+            return 0; // -infinity
+        }
+        else
+        {
+            return pow ( 10, ( dInValueRange0_1 * 35 - 35 ) / 20 );
+        }
+    }
 };