Add Stereo balance (pan) setting

src/minidexed.cpp

@@ -41,6 +41,9 @@ CMiniDexed::CMiniDexed (CConfig *pConfig, CInterruptSystem *pInterrupt,
 	m_SerialMIDI (this, pInterrupt, pConfig),
 	m_bUseSerial (false),
 	m_pSoundDevice (0),
+#ifdef ARM_ALLOW_MULTI_CORE
+	m_nActiveTGsLog2 (0),
+#endif
 	m_GetChunkTimer ("GetChunk",
 			 1000000U * pConfig->GetChunkSize ()/2 / pConfig->GetSampleRate ()),
 	m_bProfileEnabled (m_pConfig->GetProfileEnabled ())
@@ -50,6 +53,7 @@ CMiniDexed::CMiniDexed (CConfig *pConfig, CInterruptSystem *pInterrupt,
 	for (unsigned i = 0; i < CConfig::ToneGenerators; i++)
 	{
 		m_nVoiceBankID[i] = 0;
+		m_nPan[i] = 64;
 
 		m_pTG[i] = new CDexedAdapter (CConfig::MaxNotes, pConfig->GetSampleRate ());
 		assert (m_pTG[i]);
@@ -138,7 +142,11 @@ bool CMiniDexed::Initialize (void)
 		return false;
 	}
 
+#ifndef ARM_ALLOW_MULTI_CORE
 	m_pSoundDevice->SetWriteFormat (SoundFormatSigned16, 1);	// 16-bit Mono
+#else
+	m_pSoundDevice->SetWriteFormat (SoundFormatSigned16, 2);	// 16-bit Stereo
+#endif
 
 	m_nQueueSizeFrames = m_pSoundDevice->GetQueueSizeFrames ();
 
@@ -291,6 +299,19 @@ void CMiniDexed::SetVolume (unsigned nVolume, unsigned nTG)
 	m_UI.VolumeChanged (nVolume, nTG);
 }
 
+void CMiniDexed::SetPan (unsigned nPan, unsigned nTG)
+{
+	if (nPan > 127)
+	{
+		return;
+	}
+
+	assert (nTG < CConfig::ToneGenerators);
+	m_nPan[nTG] = nPan;
+
+	m_UI.PanChanged (nPan, nTG);
+}
+
 void CMiniDexed::SetMasterTune (int nMasterTune, unsigned nTG)
 {
 	if (!(-99 <= nMasterTune && nMasterTune <= 99))
@@ -322,6 +343,21 @@ void CMiniDexed::SetMIDIChannel (uint8_t uchChannel, unsigned nTG)
 		m_SerialMIDI.SetChannel (uchChannel, nTG);
 	}
 
+#ifdef ARM_ALLOW_MULTI_CORE
+	unsigned nActiveTGs = 0;
+	for (unsigned nTG = 0; nTG < CConfig::ToneGenerators; nTG++)
+	{
+		if (m_PCKeyboard.GetChannel (nTG) != CMIDIDevice::Disabled)
+		{
+			nActiveTGs++;
+		}
+	}
+
+	assert (nActiveTGs <= 8);
+	static const unsigned Log2[] = {0, 0, 1, 2, 2, 3, 3, 3, 3};
+	m_nActiveTGsLog2 = Log2[nActiveTGs];
+#endif
+
 	m_UI.MIDIChannelChanged (uchChannel, nTG);
 }
 
@@ -452,20 +488,32 @@ void CMiniDexed::ProcessSound (void)
 		}
 
 		// now mix the output of all TGs
-		int16_t SampleBuffer[nFrames];
+		int16_t SampleBuffer[nFrames][2];
 		assert (CConfig::ToneGenerators == 8);
 		for (unsigned i = 0; i < nFrames; i++)
 		{
-			int32_t nSample =   m_OutputLevel[0][i]
+			int32_t nLeft =   m_OutputLevel[0][i] * (127-m_nPan[0])
-					  + m_OutputLevel[1][i]
+					+ m_OutputLevel[1][i] * (127-m_nPan[1])
-					  + m_OutputLevel[2][i]
+					+ m_OutputLevel[2][i] * (127-m_nPan[2])
-					  + m_OutputLevel[3][i]
+					+ m_OutputLevel[3][i] * (127-m_nPan[3])
-					  + m_OutputLevel[4][i]
+					+ m_OutputLevel[4][i] * (127-m_nPan[4])
-					  + m_OutputLevel[5][i]
+					+ m_OutputLevel[5][i] * (127-m_nPan[5])
-					  + m_OutputLevel[6][i]
+					+ m_OutputLevel[6][i] * (127-m_nPan[6])
-					  + m_OutputLevel[7][i];
+					+ m_OutputLevel[7][i] * (127-m_nPan[7]);
-
+			nLeft >>= m_nActiveTGsLog2 + 7;
-			SampleBuffer[i] = (int16_t) (nSample / CConfig::ToneGenerators);
+
+			int32_t nRight =   m_OutputLevel[0][i] * m_nPan[0]
+					 + m_OutputLevel[1][i] * m_nPan[1]
+					 + m_OutputLevel[2][i] * m_nPan[2]
+					 + m_OutputLevel[3][i] * m_nPan[3]
+					 + m_OutputLevel[4][i] * m_nPan[4]
+					 + m_OutputLevel[5][i] * m_nPan[5]
+					 + m_OutputLevel[6][i] * m_nPan[6]
+					 + m_OutputLevel[7][i] * m_nPan[7];
+			nRight >>= m_nActiveTGsLog2 + 7;
+
+			SampleBuffer[i][0] = (int16_t) nLeft;
+			SampleBuffer[i][1] = (int16_t) nRight;
 		}
 
 		if (   m_pSoundDevice->Write (SampleBuffer, sizeof SampleBuffer)

src/minidexed.h

@@ -59,6 +59,7 @@ public:
 	void BankSelectLSB (unsigned nBankLSB, unsigned nTG);
 	void ProgramChange (unsigned nProgram, unsigned nTG);
 	void SetVolume (unsigned nVolume, unsigned nTG);
+	void SetPan (unsigned nPan, unsigned nTG);			// 0 .. 127
 	void SetMasterTune (int nMasterTune, unsigned nTG);		// -99 .. 99
 	void SetMIDIChannel (uint8_t uchChannel, unsigned nTG);
 
@@ -91,6 +92,7 @@ private:
 
 	CDexedAdapter *m_pTG[CConfig::ToneGenerators];
 	unsigned m_nVoiceBankID[CConfig::ToneGenerators];
+	unsigned m_nPan[CConfig::ToneGenerators];
 
 	CUserInterface m_UI;
 	CSysExFileLoader m_SysExFileLoader;
@@ -104,6 +106,7 @@ private:
 	unsigned m_nQueueSizeFrames;
 
 #ifdef ARM_ALLOW_MULTI_CORE
+	unsigned m_nActiveTGsLog2;
 	volatile TCoreStatus m_CoreStatus[CORES];
 	volatile unsigned m_nFramesToProcess;
 	int16_t m_OutputLevel[CConfig::ToneGenerators][CConfig::MaxChunkSize];

src/userinterface.cpp

@@ -44,6 +44,7 @@ CUserInterface::CUserInterface (CMiniDexed *pMiniDexed, CGPIOManager *pGPIOManag
 		m_nBank[nTG] = 0;
 		m_nProgram[nTG] = 0;
 		m_nVolume[nTG] = 0;
+		m_nPan[nTG] = 64;
 		m_nMasterTune[nTG] = 0;
 		m_uchMIDIChannel[nTG] = CMIDIDevice::Disabled;
 	}
@@ -185,6 +186,32 @@ void CUserInterface::VolumeChanged (unsigned nVolume, unsigned  nTG)
 	}
 }
 
+void CUserInterface::PanChanged (unsigned nPan, unsigned  nTG)
+{
+	assert (nPan < 128);
+	assert (nTG < CConfig::ToneGenerators);
+	m_nPan[nTG] = nPan;
+
+	if (   m_UIMode == UIModePan
+	    && m_nTG == nTG)
+	{
+		CString TG;
+		TG.Format ("TG%u", nTG+1);
+
+		char PanMarker[CConfig::LCDColumns+1];
+		memset (PanMarker, '.', CConfig::LCDColumns);
+		PanMarker[CConfig::LCDColumns] = '\0';
+		unsigned nIndex = nPan * CConfig::LCDColumns / 127;
+		if (nIndex == CConfig::LCDColumns)
+		{
+			nIndex--;
+		}
+		PanMarker[nIndex] = '\xFF';
+
+		DisplayWrite (TG, "PAN", PanMarker);
+	}
+}
+
 void CUserInterface::MasterTuneChanged (int nMasterTune, unsigned  nTG)
 {
 	assert (-99 <= nMasterTune && nMasterTune <= 99);
@@ -364,6 +391,22 @@ void CUserInterface::EncoderEventHandler (CKY040::TEvent Event)
 		m_pMiniDexed->SetVolume (nVolume, m_nTG);
 		} break;
 
+	case UIModePan: {
+		const int Increment = 128 / CConfig::LCDColumns;
+
+		int nPan = m_nPan[m_nTG] + nStep*Increment;
+		if (nPan < 0)
+		{
+			nPan = 0;
+		}
+		else if (nPan > 127)
+		{
+			nPan = 127;
+		}
+
+		m_pMiniDexed->SetPan (nPan, m_nTG);
+		} break;
+
 	case UIModeMasterTune: {
 		int nMasterTune = m_nMasterTune[m_nTG] + nStep;
 		if (nMasterTune < -99)

src/userinterface.h

@@ -42,6 +42,7 @@ public:
 	void BankSelected (unsigned nBankLSB, unsigned  nTG);		// 0 .. 127
 	void ProgramChanged (unsigned nProgram, unsigned  nTG);		// 0 .. 127
 	void VolumeChanged (unsigned nVolume, unsigned  nTG);		// 0 .. 127
+	void PanChanged (unsigned nPan, unsigned  nTG);			// 0 .. 127
 	void MasterTuneChanged (int nMasterTune, unsigned  nTG);	// -99 .. 99
 	void MIDIChannelChanged (uint8_t uchChannel, unsigned  nTG);
 
@@ -66,6 +67,7 @@ private:
 		UIModeVoiceSelect = UIModeStart,
 		UIModeBankSelect,
 		UIModeVolume,
+		UIModePan,
 		UIModeMasterTune,
 		UIModeMIDI,
 		UIModeUnknown
@@ -87,6 +89,7 @@ private:
 	unsigned m_nBank[CConfig::ToneGenerators];
 	unsigned m_nProgram[CConfig::ToneGenerators];
 	unsigned m_nVolume[CConfig::ToneGenerators];
+	unsigned m_nPan[CConfig::ToneGenerators];
 	int m_nMasterTune[CConfig::ToneGenerators];
 	uint8_t m_uchMIDIChannel[CConfig::ToneGenerators];
 };