Rewrite Evoral::Beats to use fixed beat:tick timeorigin/ticktime

10 files changed, 306 insertions, 74 deletions

diff --git a/gtk2_ardour/editor_ops.cc b/gtk2_ardour/editor_ops.cc
index 5419ce9..71a7168 100644
--- a/gtk2_ardour/editor_ops.cc
+++ b/gtk2_ardour/editor_ops.cc
@@ -4242,7 +4242,7 @@ Editor::cut_copy_points (Editing::CutCopyOp op, Evoral::Beats earliest, bool mid
 
 		/* Snap start time backwards, so copy/paste is snap aligned. */
 		if (midi) {
-			if (earliest == Evoral::Beats::max()) {
+			if (earliest == std::numeric_limits<Evoral::Beats>::max()) {
 				earliest = Evoral::Beats();  // Weird... don't offset
 			}
 			earliest.round_down_to_beat();
@@ -4296,7 +4296,7 @@ Editor::cut_copy_points (Editing::CutCopyOp op, Evoral::Beats earliest, bool mid
 void
 Editor::cut_copy_midi (CutCopyOp op)
 {
-	Evoral::Beats earliest = Evoral::Beats::max();
+	Evoral::Beats earliest = std::numeric_limits<Evoral::Beats>::max();
 	for (MidiRegionSelection::iterator i = selection->midi_regions.begin(); i != selection->midi_regions.end(); ++i) {
 		MidiRegionView* mrv = dynamic_cast<MidiRegionView*>(*i);
 		if (mrv) {
diff --git a/gtk2_ardour/midi_region_view.cc b/gtk2_ardour/midi_region_view.cc
index 3d67fef..bd1a593 100644
--- a/gtk2_ardour/midi_region_view.cc
+++ b/gtk2_ardour/midi_region_view.cc
@@ -2357,7 +2357,7 @@ MidiRegionView::note_selected (NoteBase* ev, bool add, bool extend)
 	} else {
 		/* find end of latest note selected, select all between that and the start of "ev" */
 
-		Evoral::Beats earliest = Evoral::MaxBeats;
+		Evoral::Beats earliest = std::numeric_limits<Evoral::Beats>::max();
 		Evoral::Beats latest   = Evoral::Beats();
 
 		for (Selection::iterator i = _selection.begin(); i != _selection.end(); ++i) {
@@ -2516,7 +2516,7 @@ MidiRegionView::move_selection(double dx, double dy, double cumulative_dy)
 {
 	typedef vector<boost::shared_ptr<NoteType> > PossibleChord;
 	PossibleChord to_play;
-	Evoral::Beats earliest = Evoral::MaxBeats;
+	Evoral::Beats earliest = std::numeric_limits<Evoral::Beats>::max();
 
 	for (Selection::iterator i = _selection.begin(); i != _selection.end(); ++i) {
 		if ((*i)->note()->time() < earliest) {
diff --git a/libs/ardour/ardour/midi_model.h b/libs/ardour/ardour/midi_model.h
index ea4f178..6180820 100644
--- a/libs/ardour/ardour/midi_model.h
+++ b/libs/ardour/ardour/midi_model.h
@@ -264,8 +264,8 @@ public:
 
 	bool write_section_to(boost::shared_ptr<MidiSource>     source,
 	                      const Glib::Threads::Mutex::Lock& source_lock,
-	                      Evoral::Beats                     begin = Evoral::MinBeats,
-	                      Evoral::Beats                     end   = Evoral::MaxBeats,
+	                      Evoral::Beats                     begin = Evoral::Beats(),
+	                      Evoral::Beats                     end   = std::numeric_limits<Evoral::Beats>::max(),
 	                      bool                              offset_events = false);
 
 	// MidiModel doesn't use the normal AutomationList serialisation code
diff --git a/libs/ardour/ardour/midi_source.h b/libs/ardour/ardour/midi_source.h
index c8b4263..52416e5 100644
--- a/libs/ardour/ardour/midi_source.h
+++ b/libs/ardour/ardour/midi_source.h
@@ -60,8 +60,8 @@ class LIBARDOUR_API MidiSource : virtual public Source, public boost::enable_sha
 	 */
 	int write_to (const Lock&                   lock,
 	              boost::shared_ptr<MidiSource> newsrc,
-	              Evoral::Beats                 begin = Evoral::MinBeats,
-	              Evoral::Beats                 end   = Evoral::MaxBeats);
+	              Evoral::Beats                 begin = Evoral::Beats(),
+	              Evoral::Beats                 end   = std::numeric_limits<Evoral::Beats>::max());
 
 	/** Export the midi data in the given time range to another MidiSource
 	 * \param newsrc MidiSource to which data will be written. Should be a
diff --git a/libs/ardour/midi_source.cc b/libs/ardour/midi_source.cc
index 97bce4b..1926a62 100644
--- a/libs/ardour/midi_source.cc
+++ b/libs/ardour/midi_source.cc
@@ -411,7 +411,7 @@ MidiSource::write_to (const Lock& lock, boost::shared_ptr<MidiSource> newsrc, Ev
 	newsrc->copy_automation_state_from (this);
 
 	if (_model) {
-		if (begin == Evoral::MinBeats && end == Evoral::MaxBeats) {
+		if (!begin && end == std::numeric_limits<Evoral::Beats>::max()) {
 			_model->write_to (newsrc, newsrc_lock);
 		} else {
 			_model->write_section_to (newsrc, newsrc_lock, begin, end);
@@ -425,7 +425,7 @@ MidiSource::write_to (const Lock& lock, boost::shared_ptr<MidiSource> newsrc, Ev
 
 	/* force a reload of the model if the range is partial */
 
-	if (begin != Evoral::MinBeats || end != Evoral::MaxBeats) {
+	if (!!begin || end != std::numeric_limits<Evoral::Beats>::max()) {
 		newsrc->load_model (newsrc_lock, true);
 	} else {
 		newsrc->set_model (newsrc_lock, _model);
diff --git a/libs/evoral/evoral/Beats.hpp b/libs/evoral/evoral/Beats.hpp
index e0277c4..902008d 100644
--- a/libs/evoral/evoral/Beats.hpp
+++ b/libs/evoral/evoral/Beats.hpp
@@ -22,6 +22,7 @@
 #include <float.h>
 #include <math.h>
 #include <stdint.h>
+#include <stdlib.h>
 
 #include <iostream>
 #include <limits>
@@ -33,62 +34,101 @@ namespace Evoral {
 /** Musical time in beats. */
 class /*LIBEVORAL_API*/ Beats {
 public:
-	LIBEVORAL_API static const double PPQN;
+	LIBEVORAL_API static const int32_t PPQN;
+
+	Beats() : _beats(0), _ticks(0) {}
+
+	/** Normalize so ticks is within PPQN. */
+	void normalize() {
+		// First, fix negative ticks with positive beats
+		if (_beats >= 0) {
+			while (_ticks < 0) {
+				--_beats;
+				_ticks += PPQN;
+			}
+		}
+
+		// Work with positive beats and ticks to normalize
+		const int32_t sign  = _beats < 0 ? -1 : 1;
+		int32_t       beats = abs(_beats);
+		int32_t       ticks = abs(_ticks);
+
+		// Fix ticks greater than 1 beat
+		while (ticks >= PPQN) {
+			++beats;
+			ticks -= PPQN;
+		}
 
-	Beats() : _time(0.0) {}
+		// Set fields with appropriate sign
+		_beats = sign * beats;
+		_ticks = sign * ticks;
+	}
+
+	/** Create from a precise BT time. */
+	explicit Beats(int32_t b, int32_t t) : _beats(b), _ticks(t) {
+		normalize();
+	}
 
 	/** Create from a real number of beats. */
-	explicit Beats(double time) : _time(time) {}
+	explicit Beats(double time) {
+		double       whole;
+		const double frac = modf(time, &whole);
+
+		_beats = whole;
+		_ticks = frac * PPQN;
+	}
 
 	/** Create from an integer number of beats. */
 	static Beats beats(int32_t beats) {
-		return Beats((double)beats);
+		return Beats(beats, 0);
 	}
 
 	/** Create from ticks at the standard PPQN. */
-	static Beats ticks(uint32_t ticks) {
-		return Beats(ticks / PPQN);
+	static Beats ticks(int32_t ticks) {
+		return Beats(0, ticks);
 	}
 
 	/** Create from ticks at a given rate.
 	 *
 	 * Note this can also be used to create from frames by setting ppqn to the
-	 * number of samples per beat.
+	 * number of samples per beat.  Note the resulting Beats will, like all
+	 * others, have the default PPQN, so this is a potentially lossy
+	 * conversion.
 	 */
-	static Beats ticks_at_rate(uint64_t ticks, uint32_t ppqn) {
-		return Beats((double)ticks / (double)ppqn);
+	static Beats ticks_at_rate(int64_t ticks, uint32_t ppqn) {
+		return Beats(ticks / ppqn, (ticks % ppqn) * PPQN / ppqn);
 	}
 
 	Beats& operator=(const Beats& other) {
-		_time = other._time;
+		_beats = other._beats;
+		_ticks = other._ticks;
 		return *this;
 	}
 
 	Beats round_up_to_beat() const {
-		return Evoral::Beats(ceil(_time));
+		return (_ticks == 0) ? *this : Beats(_beats + 1, 0);
 	}
 
 	Beats round_down_to_beat() const {
-		return Evoral::Beats(floor(_time));
+		return Beats(_beats, 0);
 	}
 
 	Beats snap_to(const Evoral::Beats& snap) const {
-		return Beats(ceil(_time / snap._time) * snap._time);
+		const double snap_time = snap.to_double();
+		return Beats(ceil(to_double() / snap_time) * snap_time);
 	}
 
 	inline bool operator==(const Beats& b) const {
-		/* Acceptable tolerance is 1 tick. */
-		return fabs(_time - b._time) <= (1.0 / PPQN);
+		return _beats == b._beats && _ticks == b._ticks;
 	}
 
 	inline bool operator==(double t) const {
 		/* Acceptable tolerance is 1 tick. */
-		return fabs(_time - t) <= (1.0 / PPQN);
+		return fabs(to_double() - t) <= (1.0 / PPQN);
 	}
 
 	inline bool operator==(int beats) const {
-		/* Acceptable tolerance is 1 tick. */
-		return fabs(_time - beats) <= (1.0 / PPQN);
+		return _beats == beats;
 	}
 
 	inline bool operator!=(const Beats& b) const {
@@ -96,37 +136,28 @@ public:
 	}
 
 	inline bool operator<(const Beats& b) const {
-		/* Acceptable tolerance is 1 tick. */
-		if (fabs(_time - b._time) <= (1.0 / PPQN)) {
-			return false;  /* Effectively identical. */
-		} else {
-			return _time < b._time;
-		}
+		return _beats < b._beats || (_beats == b._beats && _ticks < b._ticks);
 	}
 
 	inline bool operator<=(const Beats& b) const {
-		return operator==(b) || operator<(b);
+		return _beats < b._beats || (_beats == b._beats && _ticks <= b._ticks);
 	}
 
 	inline bool operator>(const Beats& b) const {
-		/* Acceptable tolerance is 1 tick. */
-		if (fabs(_time - b._time) <= (1.0 / PPQN)) {
-			return false;  /* Effectively identical. */
-		} else {
-			return _time > b._time;
-		}
+		return _beats > b._beats || (_beats == b._beats && _ticks > b._ticks);
 	}
 
 	inline bool operator>=(const Beats& b) const {
-		return operator==(b) || operator>(b);
+		return _beats > b._beats || (_beats == b._beats && _ticks >= b._ticks);
 	}
 
 	inline bool operator<(double b) const {
 		/* Acceptable tolerance is 1 tick. */
-		if (fabs(_time - b) <= (1.0 / PPQN)) {
+		const double time = to_double();
+		if (fabs(time - b) <= (1.0 / PPQN)) {
 			return false;  /* Effectively identical. */
 		} else {
-			return _time < b;
+			return time < b;
 		}
 	}
 
@@ -136,10 +167,11 @@ public:
 
 	inline bool operator>(double b) const {
 		/* Acceptable tolerance is 1 tick. */
-		if (fabs(_time - b) <= (1.0 / PPQN)) {
+		const double time = to_double();
+		if (fabs(time - b) <= (1.0 / PPQN)) {
 			return false;  /* Effectively identical. */
 		} else {
-			return _time > b;
+			return time > b;
 		}
 	}
 
@@ -148,60 +180,60 @@ public:
 	}
 
 	Beats operator+(const Beats& b) const {
-		return Beats(_time + b._time);
+		return Beats(_beats + b._beats, _ticks + b._ticks);
 	}
 
 	Beats operator-(const Beats& b) const {
-		return Beats(_time - b._time);
+		return Beats(_beats - b._beats, _ticks - b._ticks);
 	}
 
 	Beats operator+(double d) const {
-		return Beats(_time + d);
+		return Beats(to_double() + d);
 	}
 
 	Beats operator-(double d) const {
-		return Beats(_time - d);
+		return Beats(to_double() - d);
 	}
 
 	Beats operator-() const {
-		return Beats(-_time);
+		return Beats(-_beats, -_ticks);
 	}
 
 	template<typename Number>
 	Beats operator*(Number factor) const {
-		return Beats(_time * factor);
+		return Beats(_beats * factor, _ticks * factor);
 	}
 
 	Beats& operator+=(const Beats& b) {
-		_time += b._time;
+		_beats += b._beats;
+		_ticks += b._ticks;
+		normalize();
 		return *this;
 	}
 
 	Beats& operator-=(const Beats& b) {
-		_time -= b._time;
+		_beats -= b._beats;
+		_ticks -= b._ticks;
+		normalize();
 		return *this;
 	}
 
-	double   to_double()              const { return _time; }
-	uint64_t to_ticks()               const { return lrint(_time * PPQN); }
-	uint64_t to_ticks(uint32_t ppqn)  const { return lrint(_time * ppqn); }
+	double  to_double()              const { return (double)_beats + (_ticks / (double)PPQN); }
+	int64_t to_ticks()               const { return (int64_t)_beats * PPQN + _ticks; }
+	int64_t to_ticks(uint32_t ppqn)  const { return (int64_t)_beats * ppqn + (_ticks * ppqn / PPQN); }
 
-	uint32_t get_beats() const { return floor(_time); }
-	uint32_t get_ticks() const { return (uint32_t)lrint(fmod(_time, 1.0) * PPQN); }
+	int32_t get_beats() const { return _beats; }
+	int32_t get_ticks() const { return _ticks; }
 
-	bool operator!() const { return _time == 0; }
+	bool operator!() const { return _beats == 0 && _ticks == 0; }
 
-	static Beats min()  { return Beats(DBL_MIN); }
-	static Beats max()  { return Beats(DBL_MAX); }
-	static Beats tick() { return Beats(1.0 / PPQN); }
+	static Beats tick() { return Beats(0, 1); }
 
 private:
-	double _time;
+	int32_t _beats;
+	int32_t _ticks;
 };
 
-extern LIBEVORAL_API const Beats MaxBeats;
-extern LIBEVORAL_API const Beats MinBeats;
-
 /*
   TIL, several horrible hours later, that sometimes the compiler looks in the
   namespace of a type (Evoral::Beats in this case) for an operator, and
@@ -239,8 +271,19 @@ namespace PBD {
 namespace std {
 	template<>
 	struct numeric_limits<Evoral::Beats> {
-		static Evoral::Beats min() { return Evoral::Beats::min(); }
-		static Evoral::Beats max() { return Evoral::Beats::max(); }
+		static Evoral::Beats lowest() {
+			return Evoral::Beats(std::numeric_limits<int32_t>::min(),
+			                     std::numeric_limits<int32_t>::min());
+		}
+
+		/* We don't define min() since this has different behaviour for integral and floating point types,
+		   but Beats is used as both.  Better to avoid providing a min at all
+		   than a confusing one. */
+
+		static Evoral::Beats max() {
+			return Evoral::Beats(std::numeric_limits<int32_t>::max(),
+			                     std::numeric_limits<int32_t>::max());
+		}
 	};
 }
 
diff --git a/libs/evoral/src/types.cpp b/libs/evoral/src/types.cpp
index db061fd..9c055c2 100644
--- a/libs/evoral/src/types.cpp
+++ b/libs/evoral/src/types.cpp
@@ -16,15 +16,11 @@
  * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
-#include <limits.h>
-
 #include "evoral/Beats.hpp"
 #include "evoral/types.hpp"
 
 namespace Evoral {
 
-const double Beats::PPQN = 1920.0;
-const Beats  MaxBeats    = Evoral::Beats(DBL_MAX);
-const Beats  MinBeats    = Evoral::Beats(DBL_MIN);
+const int32_t Beats::PPQN = 1920;
 
 }
diff --git a/libs/evoral/test/BeatsTest.cpp b/libs/evoral/test/BeatsTest.cpp
new file mode 100644
index 0000000..0e3d29a
--- /dev/null
+++ b/libs/evoral/test/BeatsTest.cpp
@@ -0,0 +1,170 @@
+#include <stdlib.h>
+
+#include "BeatsTest.hpp"
+#include "evoral/Beats.hpp"
+
+CPPUNIT_TEST_SUITE_REGISTRATION(BeatsTest);
+
+using namespace Evoral;
+
+static const double delta = 1.5 / (double)Beats::PPQN;
+
+void
+BeatsTest::createTest()
+{
+	const Beats a(1, 2);
+	CPPUNIT_ASSERT_EQUAL(1, a.get_beats());
+	CPPUNIT_ASSERT_EQUAL(2, a.get_ticks());
+	CPPUNIT_ASSERT_DOUBLES_EQUAL(1 + 2 / (double)Beats::PPQN, a.to_double(), delta);
+
+	const Beats b(1.5);
+	CPPUNIT_ASSERT_EQUAL(1, b.get_beats());
+	CPPUNIT_ASSERT_EQUAL(Beats::PPQN / 2, b.get_ticks());
+	CPPUNIT_ASSERT_DOUBLES_EQUAL(1.5, b.to_double(), delta);
+
+	const Beats c = Beats::beats(6);
+	CPPUNIT_ASSERT_EQUAL(6, c.get_beats());
+	CPPUNIT_ASSERT_EQUAL(0, c.get_ticks());
+
+	const Beats d = Beats::ticks(7);
+	CPPUNIT_ASSERT_EQUAL(0, d.get_beats());
+	CPPUNIT_ASSERT_EQUAL(7, d.get_ticks());
+
+	Beats e(8, 9);
+	e = d;
+	CPPUNIT_ASSERT_EQUAL(d, e);
+
+
+	// const Beats diff = n2 - n1;
+	// CPPUNIT_ASSERT_EQUAL(-44, diff.get_beats());
+	// CPPUNIT_ASSERT_EQUAL(44 / Beats::PPQN, diff.get_ticks());
+	// CPPUNIT_ASSERT_DOUBLES_EQUAL(diff.to_double(), -44.44, delta);
+}
+
+void
+BeatsTest::addTest()
+{
+	const Beats a(1, 2);
+	const Beats b(3, 4);
+
+	// Positive + positive
+	const Beats c = a + b;
+	CPPUNIT_ASSERT_EQUAL(4, c.get_beats());
+	CPPUNIT_ASSERT_EQUAL(6, c.get_ticks());
+
+	const Beats n1(-12.34);
+	CPPUNIT_ASSERT_DOUBLES_EQUAL(-12.34, n1.to_double(), delta);
+
+	const Beats n2(-56.78);
+	CPPUNIT_ASSERT_DOUBLES_EQUAL(-56.78, n2.to_double(), delta);
+
+	// Positive + negative
+	const Beats p1(1.0);
+	const Beats p_n = p1 + n1;
+	CPPUNIT_ASSERT_EQUAL(-11, p_n.get_beats());
+	CPPUNIT_ASSERT_EQUAL((int32_t)(Beats::PPQN * -0.34), p_n.get_ticks());
+	CPPUNIT_ASSERT_DOUBLES_EQUAL(-11.34, p_n.to_double(), delta);
+
+	// Negative + positive
+	const Beats n_p = n1 + p1;
+	CPPUNIT_ASSERT_EQUAL(-11, n_p.get_beats());
+	CPPUNIT_ASSERT_EQUAL((int32_t)(Beats::PPQN * -0.34), n_p.get_ticks());
+	CPPUNIT_ASSERT_DOUBLES_EQUAL(-11.34, n_p.to_double(), delta);
+
+	// Negative + negative
+	const Beats sum = n1 + n2;
+	CPPUNIT_ASSERT_EQUAL(-69, sum.get_beats());
+	//CPPUNIT_ASSERT_EQUAL((int32_t)(Beats::PPQN * -0.12), n_p.get_ticks());
+	CPPUNIT_ASSERT_DOUBLES_EQUAL(-69.12, sum.to_double(), delta);
+}
+
+void
+BeatsTest::subtractTest()
+{
+	const Beats a(1, 2);
+	const Beats b(3, 4);
+
+	// Positive - positive
+	const Beats c = b - a;
+	CPPUNIT_ASSERT_EQUAL(2, c.get_beats());
+	CPPUNIT_ASSERT_EQUAL(2, c.get_ticks());
+
+	const Beats n1(-12.34);
+	CPPUNIT_ASSERT_DOUBLES_EQUAL(-12.34, n1.to_double(), delta);
+
+	const Beats n2(-56.78);
+	CPPUNIT_ASSERT_DOUBLES_EQUAL(-56.78, n2.to_double(), delta);
+
+	// Positive - negative
+	const Beats p1(1.0);
+	const Beats p_n = p1 - n1;
+	CPPUNIT_ASSERT_EQUAL(13, p_n.get_beats());
+	CPPUNIT_ASSERT_EQUAL((int32_t)(Beats::PPQN * 0.34), p_n.get_ticks());
+	CPPUNIT_ASSERT_DOUBLES_EQUAL(13.34, p_n.to_double(), delta);
+
+	// Negative - positive
+	const Beats n_p = n1 - p1;
+	CPPUNIT_ASSERT_EQUAL(-13, n_p.get_beats());
+	CPPUNIT_ASSERT_EQUAL((int32_t)(Beats::PPQN * -0.34), n_p.get_ticks());
+	CPPUNIT_ASSERT_DOUBLES_EQUAL(-13.34, n_p.to_double(), delta);
+
+	// Negative - negative
+	const Beats diff = n1 - n2;
+	CPPUNIT_ASSERT_EQUAL(44, diff.get_beats());
+	CPPUNIT_ASSERT_EQUAL((int32_t)lrint(Beats::PPQN * 0.44), diff.get_ticks());
+	CPPUNIT_ASSERT_DOUBLES_EQUAL(44.44, diff.to_double(), delta);
+}
+
+void
+BeatsTest::multiplyTest()
+{
+	CPPUNIT_ASSERT_DOUBLES_EQUAL(3.0, (Beats(1.5) * 2.0).to_double(), delta);
+	CPPUNIT_ASSERT_DOUBLES_EQUAL(-10.0, (Beats(5.0) * -2.0).to_double(), delta);
+	CPPUNIT_ASSERT_DOUBLES_EQUAL(-10.0, (Beats(-5.0) * 2.0).to_double(), delta);
+}
+
+void
+BeatsTest::roundTest()
+{
+	Beats a(1, 1);
+
+	// Round a up
+	const Beats au = a.round_up_to_beat();
+	CPPUNIT_ASSERT_EQUAL(au.get_beats(), 2);
+	CPPUNIT_ASSERT_EQUAL(au.get_ticks(), 0);
+
+	// Round a down
+	const Beats ad = a.round_down_to_beat();
+	CPPUNIT_ASSERT_EQUAL(ad.get_beats(), 1);
+	CPPUNIT_ASSERT_EQUAL(ad.get_ticks(), 0);
+
+	// Round result down again
+	const Beats add = ad.round_down_to_beat();
+	CPPUNIT_ASSERT_EQUAL(ad, add);
+
+	// Round result up
+	const Beats adu = ad.round_up_to_beat();
+	CPPUNIT_ASSERT_EQUAL(ad, adu);
+
+	// Snap to 1.5
+	const Beats snapped = a.snap_to(Beats(1.5));
+	CPPUNIT_ASSERT_EQUAL(snapped.get_beats(), 1);
+	CPPUNIT_ASSERT_EQUAL(snapped.get_ticks(), Beats::PPQN / 2);
+}
+
+void
+BeatsTest::convertTest()
+{
+	const Beats a = Beats::ticks_at_rate(72000, 48000);
+	CPPUNIT_ASSERT_DOUBLES_EQUAL(1, a.get_beats(), delta);
+	CPPUNIT_ASSERT_DOUBLES_EQUAL(Beats::PPQN / 2, a.get_ticks(), delta);
+	CPPUNIT_ASSERT_DOUBLES_EQUAL(1.5, a.to_double(), delta);
+
+	const Beats b = Beats::ticks_at_rate(8, 48000);
+	CPPUNIT_ASSERT_DOUBLES_EQUAL(0, b.get_beats(), delta);
+	CPPUNIT_ASSERT_DOUBLES_EQUAL(Beats::PPQN * 8 / 48000, b.get_ticks(), delta);
+	CPPUNIT_ASSERT_DOUBLES_EQUAL((8 / 48000.0), b.to_double(), delta);
+
+	CPPUNIT_ASSERT_EQUAL(int64_t(1.5 * Beats::PPQN), a.to_ticks());
+	CPPUNIT_ASSERT_EQUAL(int64_t(1.5 * 192), a.to_ticks(192));
+}
diff --git a/libs/evoral/test/BeatsTest.hpp b/libs/evoral/test/BeatsTest.hpp
new file mode 100644
index 0000000..0db3831
--- /dev/null
+++ b/libs/evoral/test/BeatsTest.hpp
@@ -0,0 +1,22 @@
+#include <cppunit/TestFixture.h>
+#include <cppunit/extensions/HelperMacros.h>
+
+class BeatsTest : public CppUnit::TestFixture
+{
+	CPPUNIT_TEST_SUITE(BeatsTest);
+	CPPUNIT_TEST(createTest);
+	CPPUNIT_TEST(addTest);
+	CPPUNIT_TEST(subtractTest);
+	CPPUNIT_TEST(multiplyTest);
+	CPPUNIT_TEST(convertTest);
+	CPPUNIT_TEST(roundTest);
+	CPPUNIT_TEST_SUITE_END();
+
+public:
+	void createTest();
+	void addTest();
+	void subtractTest();
+	void multiplyTest();
+	void convertTest();
+	void roundTest();
+};
diff --git a/libs/evoral/wscript b/libs/evoral/wscript
index 7649bb8..a83a3ca 100644
--- a/libs/evoral/wscript
+++ b/libs/evoral/wscript
@@ -134,6 +134,7 @@ def build(bld):
         # Unit tests
         obj              = bld(features = 'cxx cxxprogram')
         obj.source       = '''
+                test/BeatsTest.cpp
                 test/SequenceTest.cpp
                 test/SMFTest.cpp
                 test/RangeTest.cpp