calculate the visual split position just like the play position

3 files changed, 36 insertions, 23 deletions

diff --git a/src/engine/enginebuffer.cpp b/src/engine/enginebuffer.cpp
index 380b625e46..21d6bbc700 100644
--- a/src/engine/enginebuffer.cpp
+++ b/src/engine/enginebuffer.cpp
@@ -590,7 +590,7 @@ void EngineBuffer::ejectTrack() {
     TrackPointer pOldTrack = m_pCurrentTrack;
     m_pause.lock();
 
-    m_visualPlayPos->set(0.0, 0.0, 0.0, 0.0, 0.0, 0.0);
+    m_visualPlayPos->set(0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0);
     doSeekPlayPos(mixxx::audio::kStartFramePos, SEEK_EXACT);
 
     m_pCurrentTrack.reset();
@@ -1385,14 +1385,21 @@ void EngineBuffer::updateIndicators(double speed, int iBufferSize) {
     m_iSamplesSinceLastIndicatorUpdate += iBufferSize;
 
     const double fFractionalPlaypos = fractionalPlayposFromAbsolute(m_playPosition);
+    const double fFractionalSlipPos = fractionalPlayposFromAbsolute(m_slipPosition);
 
     const double tempoTrackSeconds = m_trackEndPositionOld.value() /
             m_trackSampleRateOld / getRateRatio();
     if (speed > 0 && fFractionalPlaypos == 1.0) {
-        // At Track end
+        // Play pos at Track end
         speed = 0;
     }
 
+    double effectiveSlipRate = m_dSlipRate;
+    if (effectiveSlipRate > 0.0 && fFractionalSlipPos == 1.0) {
+        // Slip pos at Track end
+        effectiveSlipRate = 0.0;
+    }
+
     // Update indicators that are only updated after every
     // sampleRate/kiUpdateRate samples processed.  (e.g. playposSlider)
     if (m_iSamplesSinceLastIndicatorUpdate >
@@ -1409,7 +1416,8 @@ void EngineBuffer::updateIndicators(double speed, int iBufferSize) {
             speed * m_baserate_old,
             static_cast<int>(iBufferSize) /
                     m_trackEndPositionOld.toEngineSamplePos(),
-            fractionalPlayposFromAbsolute(m_slipPosition),
+            fFractionalSlipPos,
+            effectiveSlipRate,
             tempoTrackSeconds,
             iBufferSize / kSamplesPerFrame / m_sampleRate.toDouble() * 1000000.0);
 
diff --git a/src/waveform/visualplayposition.cpp b/src/waveform/visualplayposition.cpp
index e71d0deaa1..6a816e1d52 100644
--- a/src/waveform/visualplayposition.cpp
+++ b/src/waveform/visualplayposition.cpp
@@ -29,6 +29,7 @@ void VisualPlayPosition::set(
         double rate,
         double positionStep,
         double slipPosition,
+        double slipRate,
         double tempoTrackSeconds,
         double audioBufferMicroS) {
     VisualPlayPositionData data;
@@ -36,6 +37,7 @@ void VisualPlayPosition::set(
     data.m_callbackEntrytoDac = static_cast<int>(m_dCallbackEntryToDacSecs * 1000000); // s to µs
     data.m_enginePlayPos = playPos;
     data.m_rate = rate;
+    data.m_slipRate = slipRate;
     data.m_positionStep = positionStep;
     data.m_slipPosition = slipPosition;
     data.m_tempoTrackSeconds = tempoTrackSeconds;
@@ -46,36 +48,36 @@ void VisualPlayPosition::set(
     m_valid = true;
 }
 
-double VisualPlayPosition::calcPosAtNextVSync(
+double VisualPlayPosition::calcOffsetAtNextVSync(
         VSyncThread* pVSyncThread, const VisualPlayPositionData& data) {
-    double playPos = data.m_enginePlayPos; // load playPos for the first sample in Buffer
     if (data.m_audioBufferMicroS != 0.0) {
 #if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
         Q_UNUSED(pVSyncThread);
-        int refToVSync = 0;
-        int syncIntervalTimeMicros = 0;
+        const int refToVSync = 0;
+        const int syncIntervalTimeMicros = 0;
 #else
-        int refToVSync = pVSyncThread->fromTimerToNextSyncMicros(data.m_referenceTime);
-        int syncIntervalTimeMicros = pVSyncThread->getSyncIntervalTimeMicros();
+        const int refToVSync = pVSyncThread->fromTimerToNextSyncMicros(data.m_referenceTime);
+        const int syncIntervalTimeMicros = pVSyncThread->getSyncIntervalTimeMicros();
 #endif
-        int offset = refToVSync - data.m_callbackEntrytoDac;
         // The offset is limited to the audio buffer + waveform sync interval
         // This should be sufficient to compensate jitter, but does not continue
         // in case of underflows.
-        int maxOffset = static_cast<int>(data.m_audioBufferMicroS + syncIntervalTimeMicros);
-        offset = math_clamp(offset, -maxOffset, maxOffset);
-        // add the offset for the position of the sample that will be transferred to the DAC
-        // When the next display frame is displayed
-        playPos += data.m_positionStep * offset * data.m_rate / data.m_audioBufferMicroS;
+        const int maxOffset = static_cast<int>(data.m_audioBufferMicroS + syncIntervalTimeMicros);
+        // Calculate the offset in micros for the position of the sample that will be transferred
+        // to the DAC when the next display frame is displayed
+        const int offset = math_clamp(
+                refToVSync - data.m_callbackEntrytoDac, -maxOffset, maxOffset);
+        // Apply the offset proportional to m_positionStep
+        return data.m_positionStep * static_cast<double>(offset) / data.m_audioBufferMicroS;
     }
-    // qDebug() << "playPos" << playPos << offset;
-    return playPos;
+    return 0.0;
 }
 
 double VisualPlayPosition::getAtNextVSync(VSyncThread* pVSyncThread) {
     if (m_valid) {
-        VisualPlayPositionData data = m_data.getValue();
-        return calcPosAtNextVSync(pVSyncThread, data);
+        const VisualPlayPositionData data = m_data.getValue();
+        const double offset = calcOffsetAtNextVSync(pVSyncThread, data);
+        return data.m_enginePlayPos + offset * data.m_rate;
     }
     return -1;
 }
@@ -84,9 +86,10 @@ void VisualPlayPosition::getPlaySlipAtNextVSync(VSyncThread* pVSyncThread,
         double* pPlayPosition,
         double* pSlipPosition) {
     if (m_valid) {
-        VisualPlayPositionData data = m_data.getValue();
-        *pPlayPosition = calcPosAtNextVSync(pVSyncThread, data);
-        *pSlipPosition = data.m_slipPosition;
+        const VisualPlayPositionData data = m_data.getValue();
+        const double offset = calcOffsetAtNextVSync(pVSyncThread, data);
+        *pPlayPosition = data.m_enginePlayPos + offset * data.m_rate;
+        *pSlipPosition = data.m_slipPosition + offset * data.m_slipRate;
     }
 }
 
diff --git a/src/waveform/visualplayposition.h b/src/waveform/visualplayposition.h
index d104a12533..9c2ca6ab67 100644
--- a/src/waveform/visualplayposition.h
+++ b/src/waveform/visualplayposition.h
@@ -36,6 +36,7 @@ class VisualPlayPositionData {
     double m_rate;
     double m_positionStep;
     double m_slipPosition;
+    double m_slipRate;
     double m_tempoTrackSeconds; // total track time, taking the current tempo into account
     double m_audioBufferMicroS;
 };
@@ -54,6 +55,7 @@ class VisualPlayPosition : public QObject {
             double rate,
             double positionStep,
             double slipPosition,
+            double slipRate,
             double tempoTrackSeconds,
             double audioBufferMicroS);
 
@@ -77,7 +79,7 @@ class VisualPlayPosition : public QObject {
     }
 
   private:
-    double calcPosAtNextVSync(VSyncThread* pVSyncThread, const VisualPlayPositionData& data);
+    double calcOffsetAtNextVSync(VSyncThread* pVSyncThread, const VisualPlayPositionData& data);
     ControlValueAtomic<VisualPlayPositionData> m_data;
     bool m_valid;
     QString m_key;