Return Bpm from EngineBuffer and BpmControl

src/engine/controls/bpmcontrol.cpp

@@ -162,8 +162,8 @@ BpmControl::~BpmControl() {
     delete m_pAdjustBeatsSlower;
 }
 
-double BpmControl::getBpm() const {
-    return m_pEngineBpm->get();
+mixxx::Bpm BpmControl::getBpm() const {
+    return mixxx::Bpm(m_pEngineBpm->get());
 }
 
 void BpmControl::adjustBeatsBpm(double deltaBpm) {
@@ -311,14 +311,14 @@ bool BpmControl::syncTempo() {
         return false;
     }
 
-    double fThisBpm = m_pEngineBpm->get();
-    double fThisLocalBpm = m_pLocalBpm->get();
+    const auto thisBpm = getBpm();
+    const auto thisLocalBpm = getLocalBpm();
 
-    double fOtherBpm = pOtherEngineBuffer->getBpm();
-    double fOtherLocalBpm = pOtherEngineBuffer->getLocalBpm();
+    const auto otherBpm = pOtherEngineBuffer->getBpm();
+    const auto otherLocalBpm = pOtherEngineBuffer->getLocalBpm();
 
-    //qDebug() << "this" << "bpm" << fThisBpm << "filebpm" << fThisLocalBpm;
-    //qDebug() << "other" << "bpm" << fOtherBpm << "filebpm" << fOtherLocalBpm;
+    //qDebug() << "this" << "bpm" << thisBpm << "filebpm" << thisLocalBpm;
+    //qDebug() << "other" << "bpm" << otherBpm << "filebpm" << otherLocalBpm;
 
     ////////////////////////////////////////////////////////////////////////////
     // Rough proof of how syncing works -- rryan 3/2011
@@ -346,21 +346,21 @@ bool BpmControl::syncTempo() {
     //
     // thisRateScale = ((otherFileBpm * (1.0 + otherRate)) / thisFileBpm - 1.0) / (thisRateDir * thisRateRange)
 
-    if (fOtherBpm > 0.0 && fThisBpm > 0.0) {
+    if (otherBpm.isValid() && thisBpm.isValid() && thisLocalBpm.isValid()) {
         // The desired rate is the other decks effective rate divided by this
         // deck's file BPM. This gives us the playback rate that will produce an
         // effective BPM equivalent to the other decks.
-        double desiredRate = fOtherBpm / fThisLocalBpm;
+        double desiredRate = otherBpm / thisLocalBpm;
 
         // Test if this buffer's bpm is the double of the other one, and adjust
         // the rate scale. I believe this is intended to account for our BPM
         // algorithm sometimes finding double or half BPMs. This avoids drastic
         // scales.
 
-        double fFileBpmDelta = fabs(fThisLocalBpm - fOtherLocalBpm);
-        if (fabs(fThisLocalBpm * 2.0 - fOtherLocalBpm) < fFileBpmDelta) {
+        const double fileBpmDelta = fabs(thisLocalBpm - otherLocalBpm);
+        if (fabs(thisLocalBpm * 2.0 - otherLocalBpm) < fileBpmDelta) {
             desiredRate /= 2.0;
-        } else if (fabs(fThisLocalBpm - 2.0 * fOtherLocalBpm) < fFileBpmDelta) {
+        } else if (fabs(thisLocalBpm - otherLocalBpm * 2.0) < fileBpmDelta) {
             desiredRate *= 2.0;
         }
 

src/engine/controls/bpmcontrol.h

@@ -25,8 +25,11 @@ class BpmControl : public EngineControl {
     BpmControl(const QString& group, UserSettingsPointer pConfig);
     ~BpmControl() override;
 
-    double getBpm() const;
-    double getLocalBpm() const { return m_pLocalBpm ? m_pLocalBpm->get() : 0.0; }
+    mixxx::Bpm getBpm() const;
+    mixxx::Bpm getLocalBpm() const {
+        return m_pLocalBpm ? mixxx::Bpm(m_pLocalBpm->get()) : mixxx::Bpm();
+    }
+
     // When in master sync mode, ratecontrol calls calcSyncedRate to figure out
     // how fast the track should play back.  The returned rate is usually just
     // the correct pitch to match bpms.  The usertweak argument represents

src/engine/enginebuffer.cpp

@@ -363,11 +363,11 @@ void EngineBuffer::enableIndependentPitchTempoScaling(bool bEnable,
     }
 }
 
-double EngineBuffer::getBpm() const {
+mixxx::Bpm EngineBuffer::getBpm() const {
     return m_pBpmControl->getBpm();
 }
 
-double EngineBuffer::getLocalBpm() const {
+mixxx::Bpm EngineBuffer::getLocalBpm() const {
     return m_pBpmControl->getLocalBpm();
 }
 

src/engine/enginebuffer.h

@@ -11,6 +11,7 @@
 #include "engine/engineobject.h"
 #include "engine/sync/syncable.h"
 #include "preferences/usersettings.h"
+#include "track/bpm.h"
 #include "track/track_decl.h"
 #include "util/rotary.h"
 #include "util/types.h"
@@ -97,10 +98,10 @@ class EngineBuffer : public EngineObject {
     double getSpeed() const;
     bool getScratching() const;
     bool isReverse() const;
-    // Returns current bpm value (not thread-safe)
-    double getBpm() const;
-    // Returns the BPM of the loaded track around the current position (not thread-safe)
-    double getLocalBpm() const;
+    /// Returns current bpm value (not thread-safe)
+    mixxx::Bpm getBpm() const;
+    /// Returns the BPM of the loaded track around the current position (not thread-safe)
+    mixxx::Bpm getLocalBpm() const;
     /// Sets a beatloop for the loaded track (not thread safe)
     void setBeatLoop(double startPosition, bool enabled);
     /// Sets a loop for the loaded track (not thread safe)

src/engine/sync/enginesync.cpp

@@ -471,7 +471,7 @@ Syncable* EngineSync::pickNonSyncSyncTarget(EngineChannel* pDontPick) const {
         // mix, and are primary decks.
         if (pChannel->isActive() && pChannel->isMasterEnabled() && pChannel->isPrimaryDeck()) {
             EngineBuffer* pBuffer = pChannel->getEngineBuffer();
-            if (pBuffer && pBuffer->getBpm() > 0) {
+            if (pBuffer && pBuffer->getBpm().isValid()) {
                 if (pBuffer->getSpeed() != 0.0) {
                     if (pSyncable->getSyncMode() != SYNC_NONE) {
                         // Second choice: first playing sync deck

src/track/bpm.h

@@ -152,6 +152,11 @@ inline Bpm operator/(Bpm bpm, double divisor) {
     return Bpm(bpm.value() / divisor);
 }
 
+/// Bpm can be divided by another Bpm to get a ratio (represented as a double).
+inline double operator/(Bpm bpm, Bpm otherBpm) {
+    return bpm.value() / otherBpm.value();
+}
+
 inline bool operator==(Bpm bpm1, Bpm bpm2) {
     if (!bpm1.isValid() && !bpm2.isValid()) {
         return true;