5 files changed, 51 insertions, 22 deletions

diff --git a/gtk2_ardour/automation_line.cc b/gtk2_ardour/automation_line.cc
index bf8b5c51b1..052691cb60 100644
--- a/gtk2_ardour/automation_line.cc
+++ b/gtk2_ardour/automation_line.cc
@@ -65,6 +65,7 @@ AutomationLine::AutomationLine (const string& name, TimeAxisView& tv, ArdourCanv
 	, alist (al)
 	, _parent_group (parent)
 	, _time_converter (converter ? (*converter) : default_converter)
+	, _maximum_time (max_frames)
 {
 	points_visible = false;
 	update_pending = false;
@@ -1322,3 +1323,12 @@ AutomationLine::memento_command_binder ()
 {
 	return new SimpleMementoCommandBinder<AutomationList> (*alist.get());
 }
+
+/** Set the maximum time that points on this line can be at, relative
+ *  to the start of the track or region that it is on.
+ */
+void
+AutomationLine::set_maximum_time (framepos_t t)
+{
+	_maximum_time = t;
+}
diff --git a/gtk2_ardour/automation_line.h b/gtk2_ardour/automation_line.h
index 6578e12ea4..3e23729e67 100644
--- a/gtk2_ardour/automation_line.h
+++ b/gtk2_ardour/automation_line.h
@@ -137,6 +137,11 @@ class AutomationLine : public sigc::trackable, public PBD::StatefulDestructible
 	const Evoral::TimeConverter<double, ARDOUR::sframes_t>& time_converter () const {
 		return _time_converter;
 	}
+
+	void set_maximum_time (ARDOUR::framepos_t);
+ 	ARDOUR::framepos_t maximum_time () const {
+		return _maximum_time;
+	}
 	
   protected:
 
@@ -217,6 +222,9 @@ class AutomationLine : public sigc::trackable, public PBD::StatefulDestructible
 	void model_representation (ControlPoint&, ModelRepresentation&);
 
 	PBD::ScopedConnectionList _list_connections;
+
+	/** maximum time that a point on this line can be at, relative to the start of its region or track */
+	ARDOUR::framecnt_t _maximum_time;
 	
 	friend class AudioRegionGainLine;
 };
diff --git a/gtk2_ardour/automation_region_view.cc b/gtk2_ardour/automation_region_view.cc
index a576101048..2cc3059350 100644
--- a/gtk2_ardour/automation_region_view.cc
+++ b/gtk2_ardour/automation_region_view.cc
@@ -86,6 +86,7 @@ AutomationRegionView::create_line (boost::shared_ptr<ARDOUR::AutomationList> lis
 	_line->set_height ((uint32_t)rint(trackview.current_height() - NAME_HIGHLIGHT_SIZE));
 	_line->show();
 	_line->show_all_control_points();
+	_line->set_maximum_time (_region->length());
 }
 
 bool
@@ -177,6 +178,10 @@ AutomationRegionView::set_height (double h)
 bool
 AutomationRegionView::set_position (nframes64_t pos, void* src, double* ignored)
 {
+	if (_line) {
+		_line->set_maximum_time (_region->length ());
+	}
+	
 	return RegionView::set_position(pos, src, ignored);
 }
 
@@ -186,8 +191,9 @@ AutomationRegionView::reset_width_dependent_items (double pixel_width)
 {
 	RegionView::reset_width_dependent_items(pixel_width);
 
-	if (_line)
+	if (_line) {
 		_line->reset();
+	}
 }
 
 
@@ -196,8 +202,10 @@ AutomationRegionView::region_resized (const PBD::PropertyChange& what_changed)
 {
 	RegionView::region_resized(what_changed);
 
-	if (_line)
+	if (_line) {
 		_line->reset();
+		_line->set_maximum_time (_region->length());
+	}
 }
 
 
diff --git a/gtk2_ardour/editor_drag.cc b/gtk2_ardour/editor_drag.cc
index d4b918adf2..1e3823961e 100644
--- a/gtk2_ardour/editor_drag.cc
+++ b/gtk2_ardour/editor_drag.cc
@@ -2736,12 +2736,12 @@ ControlPointDrag::start_grab (GdkEvent* event, Gdk::Cursor* /*cursor*/)
 
 	// start the grab at the center of the control point so
 	// the point doesn't 'jump' to the mouse after the first drag
-	_time_axis_view_grab_x = _point->get_x();
-	_time_axis_view_grab_y = _point->get_y();
+	_fixed_grab_x = _point->get_x();
+	_fixed_grab_y = _point->get_y();
 
 	float const fraction = 1 - (_point->get_y() / _point->line().height());
 
-	_point->line().start_drag_single (_point, _time_axis_view_grab_x, fraction);
+	_point->line().start_drag_single (_point, _fixed_grab_x, fraction);
 
 	_editor->set_verbose_canvas_cursor (_point->line().get_verbose_cursor_string (fraction),
 					    event->button.x + 10, event->button.y + 10);
@@ -2760,9 +2760,10 @@ ControlPointDrag::motion (GdkEvent* event, bool)
 		dy *= 0.1;
 	}
 
-	/* coordinate in TimeAxisView's space */
-	double cx = _time_axis_view_grab_x + _cumulative_x_drag + dx;
-	double cy = _time_axis_view_grab_y + _cumulative_y_drag + dy;
+	/* coordinate in pixels relative to the start of the region (for region-based automation)
+	   or track (for track-based automation) */
+	double cx = _fixed_grab_x + _cumulative_x_drag + dx;
+	double cy = _fixed_grab_y + _cumulative_y_drag + dy;
 
 	// calculate zero crossing point. back off by .01 to stay on the
 	// positive side of zero
@@ -2774,25 +2775,27 @@ ControlPointDrag::motion (GdkEvent* event, bool)
 	}
 
 	if (_x_constrained) {
-		cx = _time_axis_view_grab_x;
+		cx = _fixed_grab_x;
 	}
 	if (_y_constrained) {
-		cy = _time_axis_view_grab_y;
+		cy = _fixed_grab_y;
 	}
 
-	_cumulative_x_drag = cx - _time_axis_view_grab_x;
-	_cumulative_y_drag = cy - _time_axis_view_grab_y;
+	_cumulative_x_drag = cx - _fixed_grab_x;
+	_cumulative_y_drag = cy - _fixed_grab_y;
 
 	cx = max (0.0, cx);
 	cy = max (0.0, cy);
 	cy = min ((double) _point->line().height(), cy);
 
-	nframes64_t cx_frames = _editor->unit_to_frame (cx);
-
+	framepos_t cx_frames = _editor->unit_to_frame (cx);
+	
 	if (!_x_constrained) {
 		_editor->snap_to_with_modifier (cx_frames, event);
 	}
 
+	cx_frames = min (cx_frames, _point->line().maximum_time());
+
 	float const fraction = 1.0 - (cy / _point->line().height());
 
 	bool const push = Keyboard::modifier_state_contains (event->button.state, Keyboard::PrimaryModifier);
@@ -2875,8 +2878,8 @@ LineDrag::start_grab (GdkEvent* event, Gdk::Cursor* /*cursor*/)
 
 	/* store grab start in parent frame */
 
-	_time_axis_view_grab_x = cx;
-	_time_axis_view_grab_y = cy;
+	_fixed_grab_x = cx;
+	_fixed_grab_y = cy;
 
 	double fraction = 1.0 - (cy / _line->height());
 
@@ -2897,9 +2900,9 @@ LineDrag::motion (GdkEvent* event, bool)
 		dy *= 0.1;
 	}
 
-	double cy = _time_axis_view_grab_y + _cumulative_y_drag + dy;
+	double cy = _fixed_grab_y + _cumulative_y_drag + dy;
 
-	_cumulative_y_drag = cy - _time_axis_view_grab_y;
+	_cumulative_y_drag = cy - _fixed_grab_y;
 
 	cy = max (0.0, cy);
 	cy = min ((double) _line->height(), cy);
diff --git a/gtk2_ardour/editor_drag.h b/gtk2_ardour/editor_drag.h
index d710e3a639..9e503201b8 100644
--- a/gtk2_ardour/editor_drag.h
+++ b/gtk2_ardour/editor_drag.h
@@ -596,8 +596,8 @@ public:
 private:
 
 	ControlPoint* _point;
-	double _time_axis_view_grab_x;
-	double _time_axis_view_grab_y;
+	double _fixed_grab_x;
+	double _fixed_grab_y;
 	double _cumulative_x_drag;
 	double _cumulative_y_drag;
 	static double const _zero_gain_fraction;
@@ -621,8 +621,8 @@ public:
 private:
 
 	AutomationLine* _line;
-	double _time_axis_view_grab_x;
-	double _time_axis_view_grab_y;
+	double _fixed_grab_x;
+	double _fixed_grab_y;
 	uint32_t _before;
 	uint32_t _after;
 	double _cumulative_y_drag;