From 354567e5a72c3d24fb13d8b47a51b1c3859918ea Mon Sep 17 00:00:00 2001
From: nick_m <mainsbridge@gmail.com>
Date: Tue, 29 Mar 2016 04:13:37 +1100
Subject: [PATCH] Tempo ramps - switch MusicLocked tempos to beat-based
 dragging. fix various bugs wrt future-snapped tempo drags

---
 gtk2_ardour/editor.cc      |  2 ++
 gtk2_ardour/editor_drag.cc | 36 ++++++++++++++++++++++--------------
 libs/ardour/tempo.cc       |  8 +++-----
 3 files changed, 27 insertions(+), 19 deletions(-)

diff --git a/gtk2_ardour/editor.cc b/gtk2_ardour/editor.cc
index 155024f720..6e59cfc912 100644
--- a/gtk2_ardour/editor.cc
+++ b/gtk2_ardour/editor.cc
@@ -2157,6 +2157,8 @@ Editor::snap_musical() const
 	case SnapToBeatDiv4:
 	case SnapToBeatDiv3:
 	case SnapToBeatDiv2:
+	case SnapToBeat:
+	case SnapToBar:
 		return true;
 	default:
 		break;
diff --git a/gtk2_ardour/editor_drag.cc b/gtk2_ardour/editor_drag.cc
index 3305bfd040..b6083281ab 100644
--- a/gtk2_ardour/editor_drag.cc
+++ b/gtk2_ardour/editor_drag.cc
@@ -3317,18 +3317,29 @@ TempoMarkerDrag::motion (GdkEvent* event, bool first_move)
 	}
 
 	framepos_t pf;
+	double beat = 0.0;
+
 	if (!_editor->snap_musical()) {
 		pf = adjusted_current_frame (event);
 	} else {
-		pf = adjusted_current_frame (event);
+		pf = adjusted_current_frame (event, false);
 		Timecode::BBT_Time when;
 		_editor->session()->tempo_map().bbt_time (pf, when);
-		if (_editor->snap_type() == SnapToBar) {
-			_editor->session()->tempo_map().round_bbt (when, -1);
+		if (_real_section->position_lock_style() == MusicTime) {
+			if (_editor->snap_type() == SnapToBar) {
+				_editor->session()->tempo_map().round_bbt (when, -1);
+			} else {
+				_editor->session()->tempo_map().round_bbt (when, _editor->get_grid_beat_divisions (0));
+			}
+			beat = _editor->session()->tempo_map().bbt_to_beats (when);
 		} else {
-			_editor->session()->tempo_map().round_bbt (when, _editor->get_grid_beat_divisions (0));
+			if (_editor->snap_type() == SnapToBar) {
+				_editor->session()->tempo_map().round_bbt (when, -1);
+			} else {
+				_editor->session()->tempo_map().round_bbt (when, _editor->get_grid_beat_divisions (0));
+			}
+			pf = _editor->session()->tempo_map().predict_tempo_frame (_real_section, Tempo (_real_section->beats_per_minute(), _real_section->note_type()), when);
 		}
-		pf = _editor->session()->tempo_map().predict_tempo_frame (_real_section, Tempo (_real_section->beats_per_minute(), _real_section->note_type()), when);
 	}
 	Tempo const tp = _marker->tempo();
 
@@ -3340,17 +3351,14 @@ TempoMarkerDrag::motion (GdkEvent* event, bool first_move)
 		show_verbose_cursor_text (strs.str());
 	} else if (_movable) {
 
-		_marker->set_position (pf);
-		/* just here for a check/laugh
-		   if (_real_section->position_lock_style() == MusicTime) {
-		   const double baf = _editor->session()->tempo_map().beat_at_frame (pf);
-		   _editor->session()->tempo_map().gui_move_tempo_beat (_real_section, tp, baf);
-		   } else {
-		*/
-		_editor->session()->tempo_map().gui_move_tempo_frame (_real_section, tp, pf);
-		//}
+		if (_real_section->position_lock_style() == MusicTime) {
+			_editor->session()->tempo_map().gui_move_tempo_beat (_real_section, tp, beat);
+		} else {
+			_editor->session()->tempo_map().gui_move_tempo_frame (_real_section, tp, pf);
+		}
 		show_verbose_cursor_time (pf);
 	}
+	_marker->set_position (pf);
 }
 
 void
diff --git a/libs/ardour/tempo.cc b/libs/ardour/tempo.cc
index 72a1f2fea6..fec74ccfe0 100644
--- a/libs/ardour/tempo.cc
+++ b/libs/ardour/tempo.cc
@@ -1146,7 +1146,7 @@ TempoMap::gui_move_tempo_beat (TempoSection* ts,  const Tempo& bpm, const double
 		Glib::Threads::RWLock::WriterLock lm (lock);
 		TempoSection* new_section = copy_metrics_and_point (future_map, ts);
 		if (solve_map (future_map, new_section, bpm, pulse_at_beat_locked (future_map, beat))) {
-			solve_map (_metrics, ts, bpm, beat);
+			solve_map (_metrics, ts, bpm,  pulse_at_beat_locked (_metrics, beat));
 		}
 	}
 
@@ -2492,16 +2492,14 @@ TempoMap::round_bbt (BBT_Time& when, const int32_t& sub_num)
 		return;
 	} else if (sub_num == 0) {
 		const double bpb = meter_section_at (bbt_to_beats_locked (_metrics, when)).divisions_per_bar();
-		if (when.ticks > BBT_Time::ticks_per_beat / 2) {
+		if ((double) when.ticks > BBT_Time::ticks_per_beat / 2.0) {
 			++when.beats;
 			while ((double) when.beats > bpb) {
 				++when.bars;
 				when.beats -= (uint32_t) floor (bpb);
 			}
-			when.ticks = 0;
-		} else {
-			when.ticks = 0;
 		}
+		when.ticks = 0;
 		return;
 	}
 	const uint32_t ticks_one_subdivisions_worth = BBT_Time::ticks_per_beat / sub_num;