From 95bb346926e237b903059c83a70e58ed9253eaca Mon Sep 17 00:00:00 2001
From: Carl Hetherington <carl@carlh.net>
Date: Wed, 22 Dec 2010 23:43:04 +0000
Subject: [PATCH] Refactor so that all the locate-related stuff in CursorDrag
 is in one method.  Also, wait for timecode transmission to be suspended
 before sending MMC/MTC locates, rather than hoping it will be suspended in
 time.

git-svn-id: svn://localhost/ardour2/branches/3.0@8329 d708f5d6-7413-0410-9779-e7cbd77b26cf
---
 gtk2_ardour/editor_drag.cc | 53 +++++++++++++++++++-------------------
 gtk2_ardour/editor_drag.h  |  2 ++
 2 files changed, 29 insertions(+), 26 deletions(-)

diff --git a/gtk2_ardour/editor_drag.cc b/gtk2_ardour/editor_drag.cc
index d069e2e984..7f87ae0273 100644
--- a/gtk2_ardour/editor_drag.cc
+++ b/gtk2_ardour/editor_drag.cc
@@ -1983,17 +1983,33 @@ CursorDrag::CursorDrag (Editor* e, ArdourCanvas::Item* i, bool s)
 	DEBUG_TRACE (DEBUG::Drags, "New CursorDrag\n");
 }
 
+/** Do all the things we do when dragging the playhead to make it look as though
+ *  we have located, without actually doing the locate (because that would cause
+ *  the diskstream buffers to be refilled, which is too slow).
+ */
+void
+CursorDrag::fake_locate (framepos_t t)
+{
+	_editor->playhead_cursor->set_position (t);
+	
+	Session* s = _editor->session ();
+	if (s->timecode_transmission_suspended ()) {
+		framepos_t const f = _editor->playhead_cursor->current_frame;
+		s->send_mmc_locate (f);
+		s->send_full_time_code (f);
+	}
+
+	_editor->show_verbose_time_cursor (t, 10);
+	_editor->UpdateAllTransportClocks (t);
+}
+
 void
 CursorDrag::start_grab (GdkEvent* event, Gdk::Cursor* c)
 {
 	Drag::start_grab (event, c);
 
-	if (!_stop) {
-		framepos_t where = _editor->event_frame (event, 0, 0);
-
-		_editor->snap_to_with_modifier (where, event);
-		_editor->playhead_cursor->set_position (where);
-	}
+	framepos_t where = _editor->event_frame (event, 0, 0);
+	_editor->snap_to_with_modifier (where, event);
 
 	_editor->_dragging_playhead = true;
 	
@@ -2009,16 +2025,12 @@ CursorDrag::start_grab (GdkEvent* event, Gdk::Cursor* c)
 		}
 		
 		s->request_suspend_timecode_transmission ();
-
-		if (s->timecode_transmission_suspended ()) {
-			framepos_t const f = _editor->playhead_cursor->current_frame;
-			s->send_mmc_locate (f);
-			s->send_full_time_code (f);
+		while (!s->timecode_transmission_suspended ()) {
+			/* twiddle our thumbs */
 		}
 	}
-
-	_editor->show_verbose_time_cursor (_editor->playhead_cursor->current_frame, 10);
-	_editor->UpdateAllTransportClocks (_editor->playhead_cursor->current_frame);
+	
+	fake_locate (where);
 }
 
 void
@@ -2030,22 +2042,11 @@ CursorDrag::motion (GdkEvent* event, bool)
 		return;
 	}
 
-	_editor->playhead_cursor->set_position (adjusted_frame);
-
-	_editor->show_verbose_time_cursor (_editor->playhead_cursor->current_frame, 10);
-
-	Session* s = _editor->session ();
-	if (s && s->timecode_transmission_suspended ()) {
-		framepos_t const f = _editor->playhead_cursor->current_frame;
-		s->send_mmc_locate (f);
-		s->send_full_time_code (f);
-	}
+	fake_locate (adjusted_frame);
 	
-
 #ifdef GTKOSX
 	_editor->update_canvas_now ();
 #endif
-	_editor->UpdateAllTransportClocks (_editor->playhead_cursor->current_frame);
 }
 
 void
diff --git a/gtk2_ardour/editor_drag.h b/gtk2_ardour/editor_drag.h
index c294744004..3323a8b741 100644
--- a/gtk2_ardour/editor_drag.h
+++ b/gtk2_ardour/editor_drag.h
@@ -594,6 +594,8 @@ public:
 	}
 	
 private:
+	void fake_locate (framepos_t);
+	
 	bool _stop; ///< true to stop the transport on starting the drag, otherwise false
 };