2 Copyright (C) 2002 Paul Davis
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2 of the License, or
7 (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software
16 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22 #include "ardour/amp.h"
23 #include "ardour/io.h"
24 #include "ardour/route.h"
25 #include "ardour/route_group.h"
26 #include "ardour/session.h"
27 #include "ardour/session_route.h"
28 #include "ardour/dB.h"
30 #include <gtkmm/style.h>
31 #include <gdkmm/color.h>
32 #include <gtkmm2ext/utils.h>
33 #include <gtkmm2ext/fastmeter.h>
34 #include <gtkmm2ext/stop_signal.h>
35 #include <gtkmm2ext/barcontroller.h>
36 #include <gtkmm2ext/gtk_ui.h>
37 #include "midi++/manager.h"
38 #include "pbd/fastlog.h"
39 #include "pbd/stacktrace.h"
41 #include "ardour_ui.h"
42 #include "gain_meter.h"
45 #include "gui_thread.h"
47 #include "public_editor.h"
49 #include "ardour/session.h"
50 #include "ardour/route.h"
51 #include "ardour/meter.h"
55 using namespace ARDOUR;
57 using namespace Gtkmm2ext;
60 using Gtkmm2ext::Keyboard;
62 sigc::signal<void> GainMeterBase::ResetAllPeakDisplays;
63 sigc::signal<void,RouteGroup*> GainMeterBase::ResetGroupPeakDisplays;
65 map<string,Glib::RefPtr<Gdk::Pixmap> > GainMeter::metric_pixmaps;
66 Glib::RefPtr<Gdk::Pixbuf> GainMeter::slider;
70 GainMeter::setup_slider_pix ()
72 if ((slider = ::get_icon ("fader_belt")) == 0) {
73 throw failed_constructor();
77 GainMeterBase::GainMeterBase (Session& s,
78 const Glib::RefPtr<Gdk::Pixbuf>& pix,
82 // 0.781787 is the value needed for gain to be set to 0.
83 , gain_adjustment (0.781787, 0.0, 1.0, 0.01, 0.1)
84 , gain_automation_style_button ("")
85 , gain_automation_state_button ("")
90 using namespace Menu_Helpers;
92 ignore_toggle = false;
94 next_release_selects = false;
99 gain_slider = manage (new HSliderController (pix,
104 gain_slider = manage (new VSliderController (pix,
110 level_meter = new LevelMeter(_session);
112 gain_slider->signal_button_press_event().connect (sigc::mem_fun(*this, &GainMeter::start_gain_touch));
113 gain_slider->signal_button_release_event().connect (sigc::mem_fun(*this, &GainMeter::end_gain_touch));
114 gain_slider->set_name ("GainFader");
116 gain_display.set_name ("MixerStripGainDisplay");
117 gain_display.set_has_frame (false);
118 set_size_request_to_display_given_text (gain_display, "-80.g", 2, 6); /* note the descender */
119 gain_display.signal_activate().connect (sigc::mem_fun (*this, &GainMeter::gain_activated));
120 gain_display.signal_focus_in_event().connect (sigc::mem_fun (*this, &GainMeter::gain_focused), false);
121 gain_display.signal_focus_out_event().connect (sigc::mem_fun (*this, &GainMeter::gain_focused), false);
123 peak_display.set_name ("MixerStripPeakDisplay");
124 // peak_display.set_has_frame (false);
125 // peak_display.set_editable (false);
126 set_size_request_to_display_given_text (peak_display, "-80.g", 2, 6); /* note the descender */
127 max_peak = minus_infinity();
128 peak_display.set_label (_("-inf"));
129 peak_display.unset_flags (Gtk::CAN_FOCUS);
131 gain_automation_style_button.set_name ("MixerAutomationModeButton");
132 gain_automation_state_button.set_name ("MixerAutomationPlaybackButton");
134 ARDOUR_UI::instance()->tooltips().set_tip (gain_automation_state_button, _("Fader automation mode"));
135 ARDOUR_UI::instance()->tooltips().set_tip (gain_automation_style_button, _("Fader automation type"));
137 gain_automation_style_button.unset_flags (Gtk::CAN_FOCUS);
138 gain_automation_state_button.unset_flags (Gtk::CAN_FOCUS);
140 gain_automation_state_button.set_size_request(15, 15);
141 gain_automation_style_button.set_size_request(15, 15);
143 gain_astyle_menu.items().push_back (MenuElem (_("Trim")));
144 gain_astyle_menu.items().push_back (MenuElem (_("Abs")));
146 gain_astate_menu.set_name ("ArdourContextMenu");
147 gain_astyle_menu.set_name ("ArdourContextMenu");
149 gain_adjustment.signal_value_changed().connect (sigc::mem_fun(*this, &GainMeterBase::gain_adjusted));
150 peak_display.signal_button_release_event().connect (sigc::mem_fun(*this, &GainMeterBase::peak_button_release), false);
151 gain_display.signal_key_press_event().connect (sigc::mem_fun(*this, &GainMeterBase::gain_key_press), false);
153 ResetAllPeakDisplays.connect (sigc::mem_fun(*this, &GainMeterBase::reset_peak_display));
154 ResetGroupPeakDisplays.connect (sigc::mem_fun(*this, &GainMeterBase::reset_group_peak_display));
156 UI::instance()->theme_changed.connect (sigc::mem_fun(*this, &GainMeterBase::on_theme_changed));
157 ColorsChanged.connect (sigc::bind(sigc::mem_fun (*this, &GainMeterBase::color_handler), false));
158 DPIReset.connect (sigc::bind(sigc::mem_fun (*this, &GainMeterBase::color_handler), true));
161 GainMeterBase::~GainMeterBase ()
168 GainMeterBase::set_controls (boost::shared_ptr<Route> r,
169 boost::shared_ptr<PeakMeter> pm,
170 boost::shared_ptr<Amp> amp)
172 connections.clear ();
175 level_meter->set_meter (0);
176 gain_slider->set_controllable (boost::shared_ptr<PBD::Controllable>());
187 level_meter->set_meter (pm.get());
188 gain_slider->set_controllable (amp->gain_control());
190 if (!_route || _route->output()->n_ports().n_midi() == 0) {
192 gain_adjustment.set_lower (0.0);
193 gain_adjustment.set_upper (1.0);
194 gain_adjustment.set_step_increment (0.01);
195 gain_adjustment.set_page_increment (0.1);
198 gain_adjustment.set_lower (0.0);
199 gain_adjustment.set_upper (2.0);
200 gain_adjustment.set_step_increment (0.05);
201 gain_adjustment.set_page_increment (0.1);
204 if (!_route || !_route->is_hidden()) {
206 using namespace Menu_Helpers;
208 gain_astate_menu.items().clear ();
210 gain_astate_menu.items().push_back (MenuElem (_("Manual"),
211 sigc::bind (sigc::mem_fun (*(amp.get()), &Automatable::set_parameter_automation_state),
212 Evoral::Parameter(GainAutomation), (AutoState) Off)));
213 gain_astate_menu.items().push_back (MenuElem (_("Play"),
214 sigc::bind (sigc::mem_fun (*(amp.get()), &Automatable::set_parameter_automation_state),
215 Evoral::Parameter(GainAutomation), (AutoState) Play)));
216 gain_astate_menu.items().push_back (MenuElem (_("Write"),
217 sigc::bind (sigc::mem_fun (*(amp.get()), &Automatable::set_parameter_automation_state),
218 Evoral::Parameter(GainAutomation), (AutoState) Write)));
219 gain_astate_menu.items().push_back (MenuElem (_("Touch"),
220 sigc::bind (sigc::mem_fun (*(amp.get()), &Automatable::set_parameter_automation_state),
221 Evoral::Parameter(GainAutomation), (AutoState) Touch)));
223 connections.push_back (gain_automation_style_button.signal_button_press_event().connect (sigc::mem_fun(*this, &GainMeterBase::gain_automation_style_button_event), false));
224 connections.push_back (gain_automation_state_button.signal_button_press_event().connect (sigc::mem_fun(*this, &GainMeterBase::gain_automation_state_button_event), false));
226 boost::shared_ptr<AutomationControl> gc = amp->gain_control();
228 connections.push_back (gc->alist()->automation_state_changed.connect (sigc::mem_fun(*this, &GainMeter::gain_automation_state_changed)));
229 connections.push_back (gc->alist()->automation_style_changed.connect (sigc::mem_fun(*this, &GainMeter::gain_automation_style_changed)));
231 gain_automation_state_changed ();
234 connections.push_back (amp->gain_control()->Changed.connect (sigc::mem_fun (*this, &GainMeterBase::gain_changed)));
238 update_gain_sensitive ();
242 GainMeterBase::hide_all_meters ()
244 level_meter->hide_meters();
248 GainMeter::hide_all_meters ()
250 bool remove_metric_area = false;
252 GainMeterBase::hide_all_meters ();
254 if (remove_metric_area) {
255 if (meter_metric_area.get_parent()) {
256 level_meter->remove (meter_metric_area);
262 GainMeterBase::setup_meters (int len)
264 level_meter->setup_meters(len, 5);
268 GainMeter::setup_meters (int len)
270 if (!meter_metric_area.get_parent()) {
271 level_meter->pack_end (meter_metric_area, false, false);
272 meter_metric_area.show_all ();
274 GainMeterBase::setup_meters (len);
278 GainMeterBase::gain_key_press (GdkEventKey* ev)
280 if (key_is_legal_for_numeric_entry (ev->keyval)) {
281 /* drop through to normal handling */
284 /* illegal key for gain entry */
289 GainMeterBase::peak_button_release (GdkEventButton* ev)
291 /* reset peak label */
293 if (ev->button == 1 && Keyboard::modifier_state_equals (ev->state, Keyboard::PrimaryModifier|Keyboard::TertiaryModifier)) {
294 ResetAllPeakDisplays ();
295 } else if (ev->button == 1 && Keyboard::modifier_state_equals (ev->state, Keyboard::PrimaryModifier)) {
297 ResetGroupPeakDisplays (_route->route_group());
300 reset_peak_display ();
307 GainMeterBase::reset_peak_display ()
310 level_meter->clear_meters();
311 max_peak = -INFINITY;
312 peak_display.set_label (_("-Inf"));
313 peak_display.set_name ("MixerStripPeakDisplay");
317 GainMeterBase::reset_group_peak_display (RouteGroup* group)
319 if (_route && group == _route->route_group()) {
320 reset_peak_display ();
325 GainMeterBase::popup_meter_menu (GdkEventButton *ev)
327 using namespace Menu_Helpers;
329 if (meter_menu == 0) {
330 meter_menu = new Gtk::Menu;
331 MenuList& items = meter_menu->items();
333 items.push_back (MenuElem ("-inf .. +0dBFS"));
334 items.push_back (MenuElem ("-10dB .. +0dBFS"));
335 items.push_back (MenuElem ("-4 .. +0dBFS"));
336 items.push_back (SeparatorElem());
337 items.push_back (MenuElem ("-inf .. -2dBFS"));
338 items.push_back (MenuElem ("-10dB .. -2dBFS"));
339 items.push_back (MenuElem ("-4 .. -2dBFS"));
342 meter_menu->popup (1, ev->time);
346 GainMeterBase::gain_focused (GdkEventFocus* ev)
349 gain_display.select_region (0, -1);
351 gain_display.select_region (0, 0);
357 GainMeterBase::gain_activated ()
361 if (sscanf (gain_display.get_text().c_str(), "%f", &f) == 1) {
363 /* clamp to displayable values */
367 _amp->set_gain (dB_to_coefficient(f), this);
369 if (gain_display.has_focus()) {
370 PublicEditor::instance().reset_focus();
376 GainMeterBase::show_gain ()
380 float v = gain_adjustment.get_value();
384 strcpy (buf, _("-inf"));
386 snprintf (buf, sizeof (buf), "%.1f", accurate_coefficient_to_dB (slider_position_to_gain (v)));
389 snprintf (buf, sizeof (buf), "%.1f", v);
392 gain_display.set_text (buf);
396 GainMeterBase::gain_adjusted ()
398 if (!ignore_toggle) {
400 if (_route->amp() == _amp) {
402 _route->set_gain (gain_adjustment.get_value(), this);
404 _route->set_gain (slider_position_to_gain (gain_adjustment.get_value()), this);
407 _amp->set_gain (slider_position_to_gain (gain_adjustment.get_value()), this);
416 GainMeterBase::effective_gain_display ()
420 if (!_route || _route->output()->n_ports().n_midi() == 0) {
421 value = gain_to_slider_position (_amp->gain());
423 value = _amp->gain ();
426 //cerr << this << " for " << _io->name() << " EGAIN = " << value
427 // << " AGAIN = " << gain_adjustment.get_value () << endl;
428 // stacktrace (cerr, 20);
430 if (gain_adjustment.get_value() != value) {
431 ignore_toggle = true;
432 gain_adjustment.set_value (value);
433 ignore_toggle = false;
438 GainMeterBase::gain_changed ()
440 Gtkmm2ext::UI::instance()->call_slot (boost::bind (&GainMeterBase::effective_gain_display, this));
444 GainMeterBase::set_meter_strip_name (const char * name)
446 meter_metric_area.set_name (name);
450 GainMeterBase::set_fader_name (const char * name)
452 gain_slider->set_name (name);
456 GainMeterBase::update_gain_sensitive ()
458 bool x = !(_amp->gain_control()->alist()->automation_state() & Play);
459 static_cast<Gtkmm2ext::SliderController*>(gain_slider)->set_sensitive (x);
463 next_meter_point (MeterPoint mp)
467 return MeterPreFader;
471 return MeterPostFader;
488 GainMeterBase::meter_press(GdkEventButton* ev)
490 wait_for_release = false;
496 if (!ignore_toggle) {
498 if (Keyboard::is_context_menu_event (ev)) {
500 // no menu at this time.
504 if (Keyboard::is_button2_event(ev)) {
506 // Primary-button2 click is the midi binding click
507 // button2-click is "momentary"
509 if (!Keyboard::modifier_state_equals (ev->state, Keyboard::ModifierMask (Keyboard::PrimaryModifier))) {
510 wait_for_release = true;
511 old_meter_point = _route->meter_point ();
515 if (_route && (ev->button == 1 || Keyboard::is_button2_event (ev))) {
517 if (Keyboard::modifier_state_equals (ev->state, Keyboard::ModifierMask (Keyboard::PrimaryModifier|Keyboard::TertiaryModifier))) {
519 /* Primary+Tertiary-click applies change to all routes */
521 _session.foreach_route (this, &GainMeterBase::set_meter_point, next_meter_point (_route->meter_point()));
524 } else if (Keyboard::modifier_state_equals (ev->state, Keyboard::PrimaryModifier)) {
526 /* Primary-click: solo mix group.
527 NOTE: Primary-button2 is MIDI learn.
530 if (ev->button == 1) {
531 set_mix_group_meter_point (*_route, next_meter_point (_route->meter_point()));
536 /* click: change just this route */
540 _route->set_meter_point (next_meter_point (_route->meter_point()), this);
551 GainMeterBase::meter_release(GdkEventButton*)
554 if (wait_for_release){
555 wait_for_release = false;
558 set_meter_point (*_route, old_meter_point);
567 GainMeterBase::set_meter_point (Route& route, MeterPoint mp)
569 route.set_meter_point (mp, this);
573 GainMeterBase::set_mix_group_meter_point (Route& route, MeterPoint mp)
575 RouteGroup* mix_group;
577 if((mix_group = route.route_group()) != 0){
578 mix_group->apply (&Route::set_meter_point, mp, this);
580 route.set_meter_point (mp, this);
585 GainMeterBase::meter_point_clicked ()
593 GainMeterBase::start_gain_touch (GdkEventButton*)
595 _amp->gain_control()->start_touch ();
600 GainMeterBase::end_gain_touch (GdkEventButton*)
602 _amp->gain_control()->stop_touch ();
607 GainMeterBase::gain_automation_state_button_event (GdkEventButton *ev)
609 if (ev->type == GDK_BUTTON_RELEASE) {
613 switch (ev->button) {
615 gain_astate_menu.popup (1, ev->time);
625 GainMeterBase::gain_automation_style_button_event (GdkEventButton *ev)
627 if (ev->type == GDK_BUTTON_RELEASE) {
631 switch (ev->button) {
633 gain_astyle_menu.popup (1, ev->time);
642 GainMeterBase::astate_string (AutoState state)
644 return _astate_string (state, false);
648 GainMeterBase::short_astate_string (AutoState state)
650 return _astate_string (state, true);
654 GainMeterBase::_astate_string (AutoState state, bool shrt)
660 sstr = (shrt ? "M" : _("M"));
663 sstr = (shrt ? "P" : _("P"));
666 sstr = (shrt ? "T" : _("T"));
669 sstr = (shrt ? "W" : _("W"));
677 GainMeterBase::astyle_string (AutoStyle style)
679 return _astyle_string (style, false);
683 GainMeterBase::short_astyle_string (AutoStyle style)
685 return _astyle_string (style, true);
689 GainMeterBase::_astyle_string (AutoStyle style, bool shrt)
694 /* XXX it might different in different languages */
696 return (shrt ? _("Abs") : _("Abs"));
701 GainMeterBase::gain_automation_style_changed ()
705 gain_automation_style_button.set_label (astyle_string(_amp->gain_control()->alist()->automation_style()));
708 gain_automation_style_button.set_label (short_astyle_string(_amp->gain_control()->alist()->automation_style()));
714 GainMeterBase::gain_automation_state_changed ()
716 ENSURE_GUI_THREAD (*this, &GainMeterBase::gain_automation_state_changed)
722 gain_automation_state_button.set_label (astate_string(_amp->gain_control()->alist()->automation_state()));
725 gain_automation_state_button.set_label (short_astate_string(_amp->gain_control()->alist()->automation_state()));
729 x = (_amp->gain_control()->alist()->automation_state() != Off);
731 if (gain_automation_state_button.get_active() != x) {
732 ignore_toggle = true;
733 gain_automation_state_button.set_active (x);
734 ignore_toggle = false;
737 update_gain_sensitive ();
739 /* start watching automation so that things move */
741 gain_watching.disconnect();
744 gain_watching = ARDOUR_UI::RapidScreenUpdate.connect (sigc::mem_fun (*this, &GainMeterBase::effective_gain_display));
749 GainMeterBase::update_meters()
752 float mpeak = level_meter->update_meters();
754 if (mpeak > max_peak) {
756 if (mpeak <= -200.0f) {
757 peak_display.set_label (_("-inf"));
759 snprintf (buf, sizeof(buf), "%.1f", mpeak);
760 peak_display.set_label (buf);
764 peak_display.set_name ("MixerStripPeakDisplayPeak");
769 void GainMeterBase::color_handler(bool dpi)
771 color_changed = true;
772 dpi_changed = (dpi) ? true : false;
777 GainMeterBase::set_width (Width w, int len)
780 level_meter->setup_meters (len);
785 GainMeterBase::on_theme_changed()
787 style_changed = true;
790 GainMeter::GainMeter (Session& s, int fader_length)
791 : GainMeterBase (s, slider, false, fader_length)
793 gain_display_box.set_homogeneous (true);
794 gain_display_box.set_spacing (2);
795 gain_display_box.pack_start (gain_display, true, true);
797 meter_metric_area.set_name ("AudioTrackMetrics");
798 set_size_request_to_display_given_text (meter_metric_area, "-50", 0, 0);
800 gain_automation_style_button.set_name ("MixerAutomationModeButton");
801 gain_automation_state_button.set_name ("MixerAutomationPlaybackButton");
803 ARDOUR_UI::instance()->tooltips().set_tip (gain_automation_state_button, _("Fader automation mode"));
804 ARDOUR_UI::instance()->tooltips().set_tip (gain_automation_style_button, _("Fader automation type"));
806 gain_automation_style_button.unset_flags (Gtk::CAN_FOCUS);
807 gain_automation_state_button.unset_flags (Gtk::CAN_FOCUS);
809 gain_automation_state_button.set_size_request(15, 15);
810 gain_automation_style_button.set_size_request(15, 15);
812 HBox* fader_centering_box = manage (new HBox);
813 fader_centering_box->pack_start (*gain_slider, true, false);
815 fader_vbox = manage (new Gtk::VBox());
816 fader_vbox->set_spacing (0);
817 fader_vbox->pack_start (*fader_centering_box, false, false, 0);
819 hbox.set_spacing (2);
820 hbox.pack_start (*fader_vbox, true, true);
824 pack_start (gain_display_box, Gtk::PACK_SHRINK);
825 pack_start (hbox, Gtk::PACK_SHRINK);
827 meter_metric_area.signal_expose_event().connect (sigc::mem_fun(*this, &GainMeter::meter_metrics_expose));
831 GainMeter::set_controls (boost::shared_ptr<Route> r,
832 boost::shared_ptr<PeakMeter> meter,
833 boost::shared_ptr<Amp> amp)
835 if (level_meter->get_parent()) {
836 hbox.remove (*level_meter);
839 if (peak_display.get_parent()) {
840 gain_display_box.remove (peak_display);
843 if (gain_automation_state_button.get_parent()) {
844 fader_vbox->remove (gain_automation_state_button);
847 GainMeterBase::set_controls (r, meter, amp);
850 if we have a non-hidden route (ie. we're not the click or the auditioner),
851 pack some route-dependent stuff.
854 gain_display_box.pack_end (peak_display, true, true);
855 hbox.pack_end (*level_meter, true, true);
857 if (r && !r->is_hidden()) {
858 fader_vbox->pack_start (gain_automation_state_button, false, false, 0);
866 GainMeter::get_gm_width ()
869 hbox.size_request (sz);
873 Glib::RefPtr<Gdk::Pixmap>
874 GainMeter::render_metrics (Gtk::Widget& w)
876 Glib::RefPtr<Gdk::Window> win (w.get_window());
877 Glib::RefPtr<Gdk::GC> fg_gc (w.get_style()->get_fg_gc (Gtk::STATE_NORMAL));
878 Glib::RefPtr<Gdk::GC> bg_gc (w.get_style()->get_bg_gc (Gtk::STATE_NORMAL));
880 int db_points[] = { -50, -40, -20, -30, -10, -3, 0, 4 };
883 win->get_size (width, height);
885 Glib::RefPtr<Gdk::Pixmap> pixmap = Gdk::Pixmap::create (win, width, height);
887 metric_pixmaps[w.get_name()] = pixmap;
889 pixmap->draw_rectangle (bg_gc, true, 0, 0, width, height);
891 Glib::RefPtr<Pango::Layout> layout = w.create_pango_layout("");
893 for (uint32_t i = 0; i < sizeof (db_points)/sizeof (db_points[0]); ++i) {
895 float fraction = log_meter (db_points[i]);
896 gint pos = height - (gint) floor (height * fraction);
898 snprintf (buf, sizeof (buf), "%d", abs (db_points[i]));
900 layout->set_text (buf);
902 /* we want logical extents, not ink extents here */
905 layout->get_pixel_size (width, height);
907 pixmap->draw_line (fg_gc, 0, pos, 4, pos);
908 pixmap->draw_layout (fg_gc, 6, pos - (height/2), layout);
915 GainMeter::meter_metrics_expose (GdkEventExpose *ev)
917 static Glib::RefPtr<Gtk::Style> meter_style;
919 meter_style = meter_metric_area.get_style();
921 Glib::RefPtr<Gdk::Window> win (meter_metric_area.get_window());
922 Glib::RefPtr<Gdk::GC> bg_gc (meter_style->get_bg_gc (Gtk::STATE_INSENSITIVE));
923 GdkRectangle base_rect;
924 GdkRectangle draw_rect;
927 win->get_size (width, height);
929 base_rect.width = width;
930 base_rect.height = height;
934 Glib::RefPtr<Gdk::Pixmap> pixmap;
935 std::map<string,Glib::RefPtr<Gdk::Pixmap> >::iterator i = metric_pixmaps.find (meter_metric_area.get_name());
937 if (i == metric_pixmaps.end() || style_changed || dpi_changed) {
938 pixmap = render_metrics (meter_metric_area);
943 gdk_rectangle_intersect (&ev->area, &base_rect, &draw_rect);
944 win->draw_drawable (bg_gc, pixmap, draw_rect.x, draw_rect.y, draw_rect.x, draw_rect.y, draw_rect.width, draw_rect.height);
945 style_changed = false;
949 boost::shared_ptr<PBD::Controllable>
950 GainMeterBase::get_controllable()
953 return _amp->gain_control();
955 return boost::shared_ptr<PBD::Controllable>();