Keep track of MIDI region's start positions in beats, to

match the source, so that starts are not corrupted when
tempos change (#4494).


git-svn-id: svn://localhost/ardour2/branches/3.0@10976 d708f5d6-7413-0410-9779-e7cbd77b26cf

1 files changed, 134 insertions, 0 deletions

diff --git a/libs/ardour/test/framepos_minus_beats_test.cc b/libs/ardour/test/framepos_minus_beats_test.cc
new file mode 100644
index 0000000000..f80f57d969
--- /dev/null
+++ b/libs/ardour/test/framepos_minus_beats_test.cc
@@ -0,0 +1,134 @@
+#include "framepos_minus_beats_test.h"
+#include "ardour/tempo.h"
+#include "timecode/bbt_time.h"
+
+CPPUNIT_TEST_SUITE_REGISTRATION (FrameposMinusBeatsTest);
+
+using namespace std;
+using namespace ARDOUR;
+using namespace Timecode;
+
+/* Basic tests with no tempo / meter changes */
+void
+FrameposMinusBeatsTest::singleTempoTest ()
+{
+	int const sampling_rate = 48000;
+	int const bpm = 120;
+
+	double const frames_per_beat = (60 / double (bpm)) * double (sampling_rate);
+	
+	TempoMap map (sampling_rate);
+	Tempo tempo (bpm);
+	Meter meter (4, 4);
+
+	map.add_meter (meter, BBT_Time (1, 1, 0));
+	map.add_tempo (tempo, BBT_Time (1, 1, 0));
+
+	/* Subtract 1 beat from beat 3 of the first bar */
+	framepos_t r = map.framepos_minus_beats (frames_per_beat * 2, 1);
+	CPPUNIT_ASSERT_EQUAL (r, framepos_t (frames_per_beat * 1));
+}
+
+/* Test adding things that overlap a tempo change */
+void
+FrameposMinusBeatsTest::doubleTempoTest ()
+{
+	int const sampling_rate = 48000;
+
+	TempoMap map (sampling_rate);
+	Meter meter (4, 4);
+	map.add_meter (meter, BBT_Time (1, 1, 0));
+
+	/*
+	  120bpm at bar 1, 240bpm at bar 4
+	  
+	  120bpm = 24e3 samples per beat
+	  240bpm = 12e3 samples per beat
+	*/
+	
+
+	/*
+	  
+	  120bpm                                                240bpm
+	  0 beats                                               12 beats
+	  0 frames                                              288e3 frames
+	  |                 |                 |                 |                 |
+	  | 1.1 1.2 1.3 1.4 | 2.1 2.2 2.3.2.4 | 3.1 3.2 3.3 3.4 | 4.1 4.2 4.3 4.4 |
+
+	*/
+
+	Tempo tempoA (120);
+	map.add_tempo (tempoA, BBT_Time (1, 1, 0));
+	Tempo tempoB (240);
+	map.add_tempo (tempoB, BBT_Time (4, 1, 0));
+
+	/* Now some tests */
+
+	/* Subtract 1 beat from 1|2 */
+	framepos_t r = map.framepos_minus_beats (24e3, 1);
+	CPPUNIT_ASSERT_EQUAL (r, framepos_t (0));
+
+	/* Subtract 2 beats from 4|2 (over the tempo change) */
+	r = map.framepos_minus_beats (288e3 + 12e3, 2);
+	CPPUNIT_ASSERT_EQUAL (r, framepos_t (288e3 - 24e3));
+
+	/* Subtract 2.5 beats from 4|2 (over the tempo change) */
+	r = map.framepos_minus_beats (288e3 + 12e3, 2.5);
+	CPPUNIT_ASSERT_EQUAL (r, framepos_t (288e3 - 24e3 - 12e3));
+}
+
+/* Same as doubleTempoTest () except put a meter change at the same time as the
+   tempo change (which shouldn't affect anything, since we are just dealing with
+   beats)
+*/
+   
+void
+FrameposMinusBeatsTest::doubleTempoWithMeterTest ()
+{
+	int const sampling_rate = 48000;
+
+	TempoMap map (sampling_rate);
+	Meter meterA (4, 4);
+	map.add_meter (meterA, BBT_Time (1, 1, 0));
+
+	/*
+	  120bpm at bar 1, 240bpm at bar 4
+	  
+	  120bpm = 24e3 samples per beat
+	  240bpm = 12e3 samples per beat
+	*/
+	
+
+	/*
+	  
+	  120bpm                                                240bpm
+	  0 beats                                               12 beats
+	  0 frames                                              288e3 frames
+	  |                 |                 |                 |             |
+	  | 1.1 1.2 1.3 1.4 | 2.1 2.2 2.3.2.4 | 3.1 3.2 3.3 3.4 | 4.1 4.2 4.3 |
+
+	*/
+
+	Tempo tempoA (120);
+	map.add_tempo (tempoA, BBT_Time (1, 1, 0));
+	Tempo tempoB (240);
+	map.add_tempo (tempoB, BBT_Time (4, 1, 0));
+	Meter meterB (3, 4);
+	map.add_meter (meterB, BBT_Time (4, 1, 0));
+
+	/* Now some tests */
+
+	/* Subtract 1 beat from 1|2 */
+	framepos_t r = map.framepos_minus_beats (24e3, 1);
+	CPPUNIT_ASSERT_EQUAL (r, framepos_t (0));
+
+	/* Subtract 2 beats from 4|2 (over the tempo change) */
+	r = map.framepos_minus_beats (288e3 + 12e3, 2);
+	CPPUNIT_ASSERT_EQUAL (r, framepos_t (288e3 - 24e3));
+
+	/* Subtract 2.5 beats from 4|2 (over the tempo change) */
+	r = map.framepos_minus_beats (288e3 + 12e3, 2.5);
+	CPPUNIT_ASSERT_EQUAL (r, framepos_t (288e3 - 24e3 - 12e3));
+}
+
+