Make exporting of Soloed Tracks WY(S/H)IWYG

Now the export (should) exactly match the (selected) non greyed out tracks.
i.e. what you see and hear is what you export - no matter which mode of
mute/solo you choose.

This is now applied not just to export but also to export multiple.

src/Track.h

@@ -737,6 +737,8 @@ public:
 
    bool GetMute    () const { return mMute;     }
    bool GetSolo    () const { return mSolo;     }
+   bool GetNotMute () const { return !mMute;     }
+   bool GetNotSolo () const { return !mSolo;     }
    void SetMute    (bool m);
    void SetSolo    (bool s);
 

src/export/Export.cpp

@@ -250,9 +250,12 @@ std::unique_ptr<Mixer> ExportPlugin::CreateMixer(const TrackList &tracks,
          bool highQuality, MixerSpec *mixerSpec)
 {
    WaveTrackConstArray inputTracks;
+
+   bool anySolo = !(( tracks.Any<const WaveTrack>() + &WaveTrack::GetSolo ).empty());
+
    auto range = tracks.Any< const WaveTrack >()
       + (selectionOnly ? &Track::IsSelected : &Track::Any )
-      - &WaveTrack::GetMute;
+      - ( anySolo ? &WaveTrack::GetNotSolo : &WaveTrack::GetMute);
    for (auto pTrack: range)
       inputTracks.push_back(
          pTrack->SharedPointer< const WaveTrack >() );
@@ -503,10 +506,12 @@ bool Exporter::ExamineTracks()
 
    auto &tracks = TrackList::Get( *mProject );
 
+   bool anySolo = !(( tracks.Any<const WaveTrack>() + &WaveTrack::GetSolo ).empty());
+
    for (auto tr :
          tracks.Any< const WaveTrack >()
             + ( mSelectedOnly ? &Track::IsSelected : &Track::Any )
-            - &WaveTrack::GetMute
+            - ( anySolo ? &WaveTrack::GetNotSolo : &WaveTrack::GetMute)
    ) {
       mNumSelected++;
 
@@ -1364,8 +1369,8 @@ ExportMixerDialog::ExportMixerDialog( const TrackList *tracks, bool selectedOnly
 
    for (auto t :
          tracks->Any< const WaveTrack >()
-            + (anySolo ? &WaveTrack::GetSolo : ( selectedOnly ? &Track::IsSelected : &Track::Any ) )
-            - &WaveTrack::GetMute
+            + ( selectedOnly ? &Track::IsSelected : &Track::Any  )
+            - ( anySolo ? &WaveTrack::GetNotSolo :  &WaveTrack::GetMute)
    ) {
       numTracks++;
       const wxString sTrackName = (t->GetName()).Left(20);

src/export/ExportMultiple.cpp

@@ -168,8 +168,11 @@ ExportMultiple::~ExportMultiple()
 
 void ExportMultiple::CountTracksAndLabels()
 {
+   bool anySolo = !(( mTracks->Any<const WaveTrack>() + &WaveTrack::GetSolo ).empty());
+
    mNumWaveTracks =
-      (mTracks->Leaders< const WaveTrack >() - &WaveTrack::GetMute).size();
+      (mTracks->Leaders< const WaveTrack >() - 
+      (anySolo ? &WaveTrack::GetNotSolo : &WaveTrack::GetMute)).size();
 
    // only the first label track
    mLabels = *mTracks->Any< const LabelTrack >().begin();
@@ -654,9 +657,12 @@ static unsigned GetNumExportChannels( const TrackList &tracks )
    //int numMono = 0;
    /* track iteration kit */
 
+   bool anySolo = !(( tracks.Any<const WaveTrack>() + &WaveTrack::GetSolo ).empty());
+
    // Want only unmuted wave tracks.
    for (auto tr :
-         tracks.Any< const WaveTrack >() - &WaveTrack::GetMute
+         tracks.Any< const WaveTrack >() - 
+      (anySolo ? &WaveTrack::GetNotSolo : &WaveTrack::GetMute)
    ) {
       // Found a left channel
       if (tr->GetChannel() == Track::LeftChannel) {
@@ -860,8 +866,11 @@ ProgressResult ExportMultiple::ExportMultipleByTrack(bool byName,
    for (auto tr : mTracks->Selected<WaveTrack>())
       tr->SetSelected(false);
 
+   bool anySolo = !(( mTracks->Any<const WaveTrack>() + &WaveTrack::GetSolo ).empty());
+
    /* Examine all tracks in turn, collecting export information */
-   for (auto tr : mTracks->Leaders<WaveTrack>() - &WaveTrack::GetMute) {
+   for (auto tr : mTracks->Leaders<WaveTrack>() - 
+      (anySolo ? &WaveTrack::GetNotSolo : &WaveTrack::GetMute)) {
 
       // Get the times for the track
       auto channels = TrackList::Channels(tr);
@@ -940,7 +949,10 @@ ProgressResult ExportMultiple::ExportMultipleByTrack(bool byName,
    int count = 0; // count the number of sucessful runs
    ExportKit activeSetting;  // pointer to the settings in use for this export
    std::unique_ptr<ProgressDialog> pDialog;
-   for (auto tr : mTracks->Leaders<WaveTrack>() - &WaveTrack::GetMute) {
+
+   for (auto tr : mTracks->Leaders<WaveTrack>() - 
+      (anySolo ? &WaveTrack::GetNotSolo : &WaveTrack::GetMute)) {
+
       wxLogDebug( "Get setting %i", count );
       /* get the settings to use for the export from the array */
       activeSetting = exportSettings[count];