Fix current track display/broadcasting/recording when starting auto-DJ

src/mixer/playerinfo.cpp

@@ -67,6 +67,11 @@ void PlayerInfo::setTrackInfo(const QString& group, const TrackPointer& track) {
         emit trackUnloaded(group, pOld);
     }
     emit trackLoaded(group, track);
+
+    if (m_currentlyPlayingDeck >= 0 &&
+            group == PlayerManager::groupForDeck(m_currentlyPlayingDeck)) {
+        emit currentPlayingTrackChanged(track);
+    }
 }
 
 bool PlayerInfo::isTrackLoaded(const TrackPointer& pTrack) const {
@@ -113,6 +118,17 @@ void PlayerInfo::updateCurrentPlayingDeck() {
     double maxVolume = 0;
     int maxDeck = -1;
 
+    CSAMPLE_GAIN xfl, xfr;
+    // TODO: supply correct parameters to the function. If the hamster style
+    // for the crossfader is enabled, the result is currently wrong.
+    EngineXfader::getXfadeGains(m_pCOxfader->get(),
+            1.0,
+            0.0,
+            MIXXX_XFADER_ADDITIVE,
+            false,
+            &xfl,
+            &xfr);
+
     for (int i = 0; i < (int)PlayerManager::numDecks(); ++i) {
         DeckControls* pDc = getDeckControls(i);
 
@@ -129,12 +145,6 @@ void PlayerInfo::updateCurrentPlayingDeck() {
             continue;
         }
 
-        CSAMPLE_GAIN xfl, xfr;
-        // TODO: supply correct parameters to the function. If the hamster style
-        // for the crossfader is enabled, the result is currently wrong.
-        EngineXfader::getXfadeGains(m_pCOxfader->get(), 1.0, 0.0, MIXXX_XFADER_ADDITIVE, false,
-                                    &xfl, &xfr);
-
         const auto orient = static_cast<int>(pDc->m_orientation.get());
         double xfvol;
         if (orient == EngineChannel::LEFT) {
@@ -151,16 +161,16 @@ void PlayerInfo::updateCurrentPlayingDeck() {
             maxVolume = dvol;
         }
     }
-    if (maxDeck != m_currentlyPlayingDeck) {
-        m_currentlyPlayingDeck = maxDeck;
-        locker.unlock();
+    locker.unlock();
+
+    int oldDeck = m_currentlyPlayingDeck.fetchAndStoreRelease(maxDeck);
+    if (maxDeck != oldDeck) {
         emit currentPlayingDeckChanged(maxDeck);
         emit currentPlayingTrackChanged(getCurrentPlayingTrack());
     }
 }
 
 int PlayerInfo::getCurrentPlayingDeck() {
-    QMutexLocker locker(&m_mutex);
     return m_currentlyPlayingDeck;
 }
 

src/mixer/playerinfo.h

@@ -1,6 +1,7 @@
 // Helper class to have easy access
 #pragma once
 
+#include <QAtomicInt>
 #include <QMap>
 #include <QMutex>
 #include <QObject>
@@ -57,7 +58,7 @@ class PlayerInfo : public QObject {
     ControlProxy* m_pCOxfader;
     // QMap is faster than QHash for small count of elements < 50
     QMap<QString, TrackPointer> m_loadedTrackMap;
-    int m_currentlyPlayingDeck;
+    QAtomicInt m_currentlyPlayingDeck;
     QList<DeckControls*> m_deckControlList;
 
     static PlayerInfo* m_pPlayerinfo;