Tempo ramps - fix mucally-snapped dragging across the 'no time' gap (audio-locked...

[ardour.git] / libs / ardour / tempo.cc

diff --git a/libs/ardour/tempo.cc b/libs/ardour/tempo.cc
index 22e8eaf809980b5d69cbcbc0ef522ad25e628fe2..a21ec43aeeb12f15c1be36d10a6f027a627dfd91 100644 (file)
--- a/libs/ardour/tempo.cc
+++ b/libs/ardour/tempo.cc
@@ -1540,12 +1540,30 @@ TempoMap::frame_at_pulse (const double& pulse) const
 double
 TempoMap::beat_at_frame_locked (const Metrics& metrics, const framecnt_t& frame) const
 {
-       const MeterSection& prev_m = meter_section_at_locked (metrics, frame);
        const TempoSection& ts = tempo_section_at_locked (metrics, frame);
-       if (frame < prev_m.frame()) {
+       MeterSection* prev_m = 0;
+       MeterSection* next_m = 0;
+
+       for (Metrics::const_iterator i = metrics.begin(); i != metrics.end(); ++i) {
+               MeterSection* m;
+               if ((m = dynamic_cast<MeterSection*> (*i)) != 0) {
+                       if (prev_m && m->frame() > frame) {
+                               next_m = m;
+                               break;
+                       }
+                       prev_m = m;
+               }
+       }
+       if (frame < prev_m->frame()) {
                return 0.0;
        }
-       return prev_m.beat() + (ts.pulse_at_frame (frame, _frame_rate) - prev_m.pulse()) * prev_m.note_divisor();
+       const double beat = prev_m->beat() + (ts.pulse_at_frame (frame, _frame_rate) - prev_m->pulse()) * prev_m->note_divisor();
+
+       if (next_m && next_m->beat() < beat) {
+               return next_m->beat();
+       }
+
+       return beat;
 }
 
 double