add support for using - as prefix keys to enter a negative value in an audio clock. so far only used for session timecode offset option clock

git-svn-id: svn://localhost/ardour2/branches/3.0@13443 d708f5d6-7413-0410-9779-e7cbd77b26cf

4 files changed, 23 insertions, 3 deletions

diff --git a/gtk2_ardour/audio_clock.cc b/gtk2_ardour/audio_clock.cc
index dbc0db38ff..b69ffa7329 100644
--- a/gtk2_ardour/audio_clock.cc
+++ b/gtk2_ardour/audio_clock.cc
@@ -74,6 +74,8 @@ AudioClock::AudioClock (const string& clock_name, bool transient, const string&
 	, layout_x_offset (0)
 	, em_width (0)
 	, _edit_by_click_field (false)
+	, _negative_allowed (false)
+	, edit_is_negative (false)
 	, editing_attr (0)
 	, foreground_attr (0)
 	, first_height (0)
@@ -574,8 +576,10 @@ AudioClock::start_edit (Field f)
 		edit_string.clear ();
 		_layout->set_text ("");
 	}
+
 	input_string.clear ();
 	editing = true;
+	edit_is_negative = false;
 
 	if (f) {
 		input_string = get_field (f);
@@ -698,6 +702,7 @@ AudioClock::end_edit (bool modify)
 	} else {
 
 		editing = false;
+		edit_is_negative = false;
 		_layout->set_attributes (normal_attributes);
 		_layout->set_text (pre_edit_string);
 	}
@@ -1344,12 +1349,15 @@ AudioClock::on_key_press_event (GdkEventKey* ev)
 
 	case GDK_minus:
 	case GDK_KP_Subtract:
-		end_edit_relative (false);
+		if (_negative_allowed && input_string.empty()) {
+				edit_is_negative = true;
+		} else {
+			end_edit_relative (false);
+		}
 		return true;
 		break;
 
 	case GDK_plus:
-	case GDK_KP_Add:
 		end_edit_relative (true);
 		return true;
 		break;
@@ -1933,6 +1941,7 @@ AudioClock::frames_from_timecode_string (const string& str) const
 		return 0;
 	}
 
+	TC.negative = edit_is_negative;
 	TC.rate = _session->timecode_frames_per_second();
 	TC.drop= _session->timecode_drop_frames();
 
@@ -2220,3 +2229,9 @@ AudioClock::dpi_reset ()
 	first_height = 0;
 	queue_resize ();
 }
+
+void
+AudioClock::set_negative_allowed (bool yn)
+{
+	_negative_allowed = yn;
+}
diff --git a/gtk2_ardour/audio_clock.h b/gtk2_ardour/audio_clock.h
index 4a077da7d8..03ed27edbd 100644
--- a/gtk2_ardour/audio_clock.h
+++ b/gtk2_ardour/audio_clock.h
@@ -76,6 +76,7 @@ class AudioClock : public CairoWidget, public ARDOUR::SessionHandlePtr
 	framepos_t current_time (framepos_t position = 0) const;
 	framepos_t current_duration (framepos_t position = 0) const;
 	void set_session (ARDOUR::Session *s);
+        void set_negative_allowed (bool yn); 
 
 	sigc::signal<void> ValueChanged;
 	sigc::signal<void> mode_changed;
@@ -104,6 +105,8 @@ class AudioClock : public CairoWidget, public ARDOUR::SessionHandlePtr
 	int              em_width;
 	bool             _edit_by_click_field;
 	int              _mode_width[4]; /* enum Mode entries */
+        bool             _negative_allowed;
+        bool             edit_is_negative;
 
 	Glib::RefPtr<Pango::Layout> _layout;
 	Glib::RefPtr<Pango::Layout> _left_layout;
@@ -195,7 +198,7 @@ class AudioClock : public CairoWidget, public ARDOUR::SessionHandlePtr
 	bool bbt_validate_edit (const std::string&);
 	bool minsec_validate_edit (const std::string&);
 
-	framepos_t frames_from_timecode_string (const std::string&) const;
+        framepos_t frames_from_timecode_string (const std::string&) const;
 	framepos_t frames_from_bbt_string (framepos_t, const std::string&) const;
 	framepos_t frame_duration_from_bbt_string (framepos_t, const std::string&) const;
 	framepos_t frames_from_minsec_string (const std::string&) const;
diff --git a/gtk2_ardour/option_editor.h b/gtk2_ardour/option_editor.h
index 68ffe1f969..454b0f2245 100644
--- a/gtk2_ardour/option_editor.h
+++ b/gtk2_ardour/option_editor.h
@@ -541,6 +541,7 @@ public:
 	void set_session (ARDOUR::Session *);
 
         Gtk::Widget& tip_widget() { return _clock; }
+        AudioClock& clock() { return _clock; }
 
 private:
 	void save_clock_time ();
diff --git a/gtk2_ardour/session_option_editor.cc b/gtk2_ardour/session_option_editor.cc
index 5059555fff..c6daac9454 100644
--- a/gtk2_ardour/session_option_editor.cc
+++ b/gtk2_ardour/session_option_editor.cc
@@ -99,6 +99,7 @@ SessionOptionEditor::SessionOptionEditor (Session* s)
 		);
 
 	co->set_session (_session);
+	co->clock().set_negative_allowed (true);
 
 	add_option (_("Timecode"), co);