Adding recording example configuration and improving error message in headphone reproduction

conf/VACore.recording.ini

+#
+#  -------------------------------------------------------------------------------------------
+#
+#    VVV        VVV A
+#     VVV      VVV AAA        Virtual Acoustics (VA)
+#      VVV    VVV   AAA       Real-time auralisation for virtual reality    
+#       VVV  VVV     AAA
+#        VVVVVV       AAA     (c) Copyright Institut of Technical Acoustics (ITA)
+#         VVVV         AAA        RWTH Aachen University (http://www.akustik.rwth-aachen.de)
+#
+#  -------------------------------------------------------------------------------------------
+#
+#	This minimalistic configuration file is an example how to simulate and record 
+#	the audio stream of a binaural rendering with headphone-equalized output.
+#
+
+
+[Paths]
+conf_dir = conf
+data_dir = data
+
+[Macros]
+DemoSound = WelcomeToVA.wav
+DefaultHRIR = ITA_Artificial_Head_5x5_44kHz_128.v17.ir.daff
+ProjectName = MyOfflineRecordingProject
+
+[Debug]
+LogLevel = 4
+
+[Audio driver]
+Driver = Virtual
+Device = trigger
+Samplerate = 44100
+Buffersize = 64
+OutputChannels = 2
+
+[Renderer:MyBinauralFreeField]
+Class = BinauralFreeField
+Enabled = true
+Reproductions = MyHeadphones
+RecordOutputEnabled = true
+RecordOutputFilePath = $(ProjectName)_rendering.wav
+
+[Reproduction:MyHeadphones]
+Class = Headphones
+Enabled = true
+HpIRInvFile = HD650_all_inv.wav
+HpIRInvCalibrationGainDecibel = 0.1
+Outputs = MyDesktopHP
+RecordOutputEnabled = true
+RecordOutputFilePath = $(ProjectName)_reproduction.wav
+
+[Setup]
+[Output:MyDesktopHP]
+Description = Desktop user with headphones
+Devices = MyHP
+
+[OutputDevice:MyHP]
+Type = HP
+Description = Headphone hardware device (two-channels)
+Channels = 1,2

src/Reproduction/Binaural/VAHeadphonesReproduction.cpp

@@ -85,7 +85,11 @@ CVAHeadphonesReproduction::CVAHeadphonesReproduction( const CVAAudioReproduction
 
 	std::string sFilePath = m_oParams.pCore->GetCoreConfig()->mMacros.SubstituteMacros( sFilePathRaw );	;
 
-	m_sfHpIRInv.Load( m_oParams.pCore->FindFilePath( sFilePath ) ); // sets length to given number of samples
+	std::string sFinalFilePath = oParams.pCore->FindFilePath( sFilePath );
+	if( !doesPathExist( sFinalFilePath ) )
+		VA_EXCEPT2( INVALID_PARAMETER, "Headphone EQ impulse response file '" + sFilePath + "' could not be found. Please make sure the directory is added as a search path." );
+
+	m_sfHpIRInv.Load( sFinalFilePath ); // sets length to given number of samples
 
 	if( m_sfHpIRInv.channels() != 2 )
 		VA_EXCEPT2( INVALID_PARAMETER, "Headphone EQ impulse response '" + sFilePath + "' requires two channels" );