src/wx/audio_mapping_view.cc

   1 /*
   2     Copyright (C) 2013-2019 Carl Hetherington <cth@carlh.net>
   3
   4     This file is part of DCP-o-matic.
   5
   6     DCP-o-matic is free software; you can redistribute it and/or modify
   7     it under the terms of the GNU General Public License as published by
   8     the Free Software Foundation; either version 2 of the License, or
   9     (at your option) any later version.
  10
  11     DCP-o-matic is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14     GNU General Public License for more details.
  15
  16     You should have received a copy of the GNU General Public License
  17     along with DCP-o-matic.  If not, see <http://www.gnu.org/licenses/>.
  18
  19 */
  20
  21 /** @file  src/wx/audio_mapping_view.cc
  22  *  @brief AudioMappingView class and helpers.
  23  */
  24
  25 #include "audio_mapping_view.h"
  26 #include "wx_util.h"
  27 #include "audio_gain_dialog.h"
  28 #include "lib/audio_mapping.h"
  29 #include "lib/util.h"
  30 #include <dcp/locale_convert.h>
  31 #include <dcp/types.h>
  32 #include <wx/wx.h>
  33 #include <wx/renderer.h>
  34 #include <wx/grid.h>
  35 #include <wx/graphics.h>
  36 #include <boost/foreach.hpp>
  37 #include <iostream>
  38
  39 using std::cout;
  40 using std::list;
  41 using std::string;
  42 using std::min;
  43 using std::max;
  44 using std::vector;
  45 using std::pair;
  46 using std::make_pair;
  47 using boost::shared_ptr;
  48 using boost::optional;
  49 using dcp::locale_convert;
  50
  51 #define INDICATOR_SIZE 20
  52 #define GRID_SPACING 32
  53 #define LEFT_WIDTH (GRID_SPACING * 3)
  54 #define TOP_HEIGHT (GRID_SPACING * 2)
  55
  56 enum {
  57         ID_off = 1,
  58         ID_full = 2,
  59         ID_minus6dB = 3,
  60         ID_edit = 4
  61 };
  62
  63 AudioMappingView::AudioMappingView (wxWindow* parent)
  64         : wxPanel (parent, wxID_ANY)
  65         , _menu_input (0)
  66         , _menu_output (1)
  67 {
  68         _menu = new wxMenu;
  69         _menu->Append (ID_off, _("Off"));
  70         _menu->Append (ID_full, _("Full"));
  71         _menu->Append (ID_minus6dB, _("-6dB"));
  72         _menu->Append (ID_edit, _("Edit..."));
  73
  74         _body = new wxPanel (this, wxID_ANY);
  75         _vertical_scroll = new wxScrollBar (this, wxID_ANY, wxDefaultPosition, wxDefaultSize, wxSB_VERTICAL);
  76         _horizontal_scroll = new wxScrollBar (this, wxID_ANY);
  77
  78         Bind (wxEVT_SIZE, boost::bind(&AudioMappingView::size, this, _1));
  79         Bind (wxEVT_MENU, boost::bind(&AudioMappingView::off, this), ID_off);
  80         Bind (wxEVT_MENU, boost::bind(&AudioMappingView::full, this), ID_full);
  81         Bind (wxEVT_MENU, boost::bind(&AudioMappingView::minus6dB, this), ID_minus6dB);
  82         Bind (wxEVT_MENU, boost::bind(&AudioMappingView::edit, this), ID_edit);
  83         Bind (wxEVT_MOUSEWHEEL, boost::bind(&AudioMappingView::mouse_wheel, this, _1));
  84         _body->Bind (wxEVT_PAINT, boost::bind(&AudioMappingView::paint, this));
  85         _body->Bind (wxEVT_LEFT_DOWN, boost::bind(&AudioMappingView::left_down, this, _1));
  86         _body->Bind (wxEVT_RIGHT_DOWN, boost::bind(&AudioMappingView::right_down, this, _1));
  87         _body->Bind (wxEVT_MOTION, boost::bind(&AudioMappingView::motion, this, _1));
  88         _vertical_scroll->Bind (wxEVT_SCROLL_TOP, boost::bind(&AudioMappingView::scroll, this));
  89         _vertical_scroll->Bind (wxEVT_SCROLL_BOTTOM, boost::bind(&AudioMappingView::scroll, this));
  90         _vertical_scroll->Bind (wxEVT_SCROLL_LINEUP, boost::bind(&AudioMappingView::scroll, this));
  91         _vertical_scroll->Bind (wxEVT_SCROLL_LINEDOWN, boost::bind(&AudioMappingView::scroll, this));
  92         _vertical_scroll->Bind (wxEVT_SCROLL_PAGEUP, boost::bind(&AudioMappingView::scroll, this));
  93         _vertical_scroll->Bind (wxEVT_SCROLL_PAGEDOWN, boost::bind(&AudioMappingView::scroll, this));
  94         _vertical_scroll->Bind (wxEVT_SCROLL_THUMBTRACK, boost::bind(&AudioMappingView::scroll, this));
  95         _vertical_scroll->Bind (wxEVT_SCROLL_THUMBRELEASE, boost::bind(&AudioMappingView::scroll, this));
  96         _horizontal_scroll->Bind (wxEVT_SCROLL_TOP, boost::bind(&AudioMappingView::scroll, this));
  97         _horizontal_scroll->Bind (wxEVT_SCROLL_BOTTOM, boost::bind(&AudioMappingView::scroll, this));
  98         _horizontal_scroll->Bind (wxEVT_SCROLL_LINEUP, boost::bind(&AudioMappingView::scroll, this));
  99         _horizontal_scroll->Bind (wxEVT_SCROLL_LINEDOWN, boost::bind(&AudioMappingView::scroll, this));
 100         _horizontal_scroll->Bind (wxEVT_SCROLL_PAGEUP, boost::bind(&AudioMappingView::scroll, this));
 101         _horizontal_scroll->Bind (wxEVT_SCROLL_PAGEDOWN, boost::bind(&AudioMappingView::scroll, this));
 102         _horizontal_scroll->Bind (wxEVT_SCROLL_THUMBTRACK, boost::bind(&AudioMappingView::scroll, this));
 103         _horizontal_scroll->Bind (wxEVT_SCROLL_THUMBRELEASE, boost::bind(&AudioMappingView::scroll, this));
 104 }
 105
 106 void
 107 AudioMappingView::size (wxSizeEvent& ev)
 108 {
 109         setup ();
 110         ev.Skip ();
 111 }
 112
 113 void
 114 AudioMappingView::setup ()
 115 {
 116         wxSize const s = GetSize();
 117         int const w = _vertical_scroll->GetSize().GetWidth();
 118         int const h = _horizontal_scroll->GetSize().GetHeight();
 119
 120         _vertical_scroll->SetPosition (wxPoint(s.GetWidth() - w, 0));
 121         _vertical_scroll->SetSize (wxSize(w, max(0, s.GetHeight() - h)));
 122
 123         _body->SetSize (wxSize(max(0, s.GetWidth() - w), max(0, s.GetHeight() - h)));
 124
 125         _horizontal_scroll->SetPosition (wxPoint(0, s.GetHeight() - h));
 126         _horizontal_scroll->SetSize (wxSize(max(0, s.GetWidth() - w), h));
 127
 128         _vertical_scroll->SetScrollbar (
 129                 _vertical_scroll->GetThumbPosition(),
 130                 s.GetHeight() - h - 8,
 131                 GRID_SPACING * (2 + _input_channels.size()),
 132                 GRID_SPACING,
 133                 true
 134                 );
 135
 136         _horizontal_scroll->SetScrollbar (
 137                 _horizontal_scroll->GetThumbPosition(),
 138                 s.GetWidth() - w - 8,
 139                 GRID_SPACING * (3 + _output_channels.size()),
 140                 GRID_SPACING,
 141                 true);
 142 }
 143
 144 void
 145 AudioMappingView::scroll ()
 146 {
 147         Refresh ();
 148 }
 149
 150 void
 151 AudioMappingView::paint_static (wxDC& dc, wxGraphicsContext* gc)
 152 {
 153         gc->SetAntialiasMode (wxANTIALIAS_DEFAULT);
 154         dc.SetFont (wxSWISS_FONT->Bold());
 155         wxCoord label_width;
 156         wxCoord label_height;
 157
 158         /* DCP label at the top */
 159
 160         dc.GetTextExtent (_("DCP"), &label_width, &label_height);
 161         dc.DrawText (_("DCP"), LEFT_WIDTH + (_output_channels.size() * GRID_SPACING - label_width) / 2, (GRID_SPACING - label_height) / 2);
 162
 163         /* Content label on the left */
 164
 165         dc.GetTextExtent (_("Content"), &label_width, &label_height);
 166         dc.DrawRotatedText (
 167                 _("Content"),
 168                 (GRID_SPACING - label_height) / 2,
 169                 TOP_HEIGHT + (_input_channels.size() * GRID_SPACING + label_width) / 2,
 170                 90
 171                 );
 172
 173         dc.SetFont (*wxSWISS_FONT);
 174         gc->SetPen (*wxBLACK_PEN);
 175 }
 176
 177 void
 178 AudioMappingView::paint_column_labels (wxDC& dc, wxGraphicsContext* gc)
 179 {
 180         wxCoord label_width;
 181         wxCoord label_height;
 182         int N = 0;
 183         BOOST_FOREACH (string i, _output_channels) {
 184                 dc.GetTextExtent (std_to_wx(i), &label_width, &label_height);
 185                 dc.DrawText (std_to_wx(i), LEFT_WIDTH + GRID_SPACING * N + (GRID_SPACING - label_width) / 2, GRID_SPACING + (GRID_SPACING - label_height) / 2);
 186                 ++N;
 187         }
 188
 189         wxGraphicsPath lines = gc->CreatePath ();
 190         lines.MoveToPoint (LEFT_WIDTH, GRID_SPACING);
 191         lines.AddLineToPoint (LEFT_WIDTH + _output_channels.size() * GRID_SPACING, GRID_SPACING);
 192         lines.MoveToPoint (LEFT_WIDTH, GRID_SPACING * 2);
 193         lines.AddLineToPoint (LEFT_WIDTH + _output_channels.size() * GRID_SPACING, GRID_SPACING * 2);
 194         gc->StrokePath (lines);
 195 }
 196
 197 void
 198 AudioMappingView::paint_column_lines (wxGraphicsContext* gc)
 199 {
 200         wxGraphicsPath lines = gc->CreatePath ();
 201         for (size_t i = 0; i < _output_channels.size(); ++i) {
 202                 lines.MoveToPoint    (LEFT_WIDTH + GRID_SPACING * i, GRID_SPACING);
 203                 lines.AddLineToPoint (LEFT_WIDTH + GRID_SPACING * i, TOP_HEIGHT + _input_channels.size() * GRID_SPACING);
 204         }
 205         lines.MoveToPoint    (LEFT_WIDTH + GRID_SPACING * _output_channels.size(), GRID_SPACING);
 206         lines.AddLineToPoint (LEFT_WIDTH + GRID_SPACING * _output_channels.size(), TOP_HEIGHT + _input_channels.size() * GRID_SPACING);
 207         gc->StrokePath (lines);
 208 }
 209
 210 void
 211 AudioMappingView::paint_row_labels (wxDC& dc, wxGraphicsContext* gc)
 212 {
 213         wxCoord label_width;
 214         wxCoord label_height;
 215         wxGraphicsPath lines = gc->CreatePath ();
 216
 217         /* Row channel labels */
 218
 219         int N = 0;
 220         BOOST_FOREACH (string i, _input_channels) {
 221                 dc.GetTextExtent (std_to_wx(i), &label_width, &label_height);
 222                 dc.DrawText (std_to_wx(i), GRID_SPACING * 2 + (GRID_SPACING - label_width) / 2, TOP_HEIGHT + GRID_SPACING * N + (GRID_SPACING - label_height) / 2);
 223                 ++N;
 224         }
 225
 226         /* Vertical lines on the left */
 227
 228         for (int i = 1; i < 3; ++i) {
 229                 lines.MoveToPoint    (GRID_SPACING * i, TOP_HEIGHT);
 230                 lines.AddLineToPoint (GRID_SPACING * i, TOP_HEIGHT + _input_channels.size() * GRID_SPACING);
 231         }
 232
 233         /* Group labels and lines */
 234
 235         int y = TOP_HEIGHT;
 236         BOOST_FOREACH (Group i, _input_groups) {
 237                 int const height = (i.to - i.from + 1) * GRID_SPACING;
 238                 dc.GetTextExtent (std_to_wx(i.name), &label_width, &label_height);
 239                 if (label_width > height) {
 240                         label_width = height - 8;
 241                 }
 242
 243                 {
 244                         int yp = y;
 245                         if ((yp - 2 * GRID_SPACING) < dc.GetLogicalOrigin().y) {
 246                                 yp += dc.GetLogicalOrigin().y;
 247                         }
 248
 249                         wxCoord old_x, old_y, old_width, old_height;
 250                         dc.GetClippingBox (&old_x, &old_y, &old_width, &old_height);
 251                         dc.DestroyClippingRegion ();
 252                         dc.SetClippingRegion (GRID_SPACING, yp + 4, GRID_SPACING, height - 8);
 253
 254                         dc.DrawRotatedText (
 255                                 std_to_wx(i.name),
 256                                 GRID_SPACING + (GRID_SPACING - label_height) / 2,
 257                                 y + (height + label_width) / 2,
 258                                 90
 259                                 );
 260
 261                         dc.DestroyClippingRegion ();
 262                         dc.SetClippingRegion (old_x, old_y, old_width, old_height);
 263                 }
 264
 265                 lines.MoveToPoint    (GRID_SPACING,     y);
 266                 lines.AddLineToPoint (GRID_SPACING * 2, y);
 267                 y += height;
 268         }
 269
 270         lines.MoveToPoint    (GRID_SPACING,     y);
 271         lines.AddLineToPoint (GRID_SPACING * 2, y);
 272
 273         gc->StrokePath (lines);
 274 }
 275
 276 void
 277 AudioMappingView::paint_row_lines (wxGraphicsContext* gc)
 278 {
 279         wxGraphicsPath lines = gc->CreatePath ();
 280         for (size_t i = 0; i < _input_channels.size(); ++i) {
 281                 lines.MoveToPoint (GRID_SPACING * 2, TOP_HEIGHT + GRID_SPACING * i);
 282                 lines.AddLineToPoint (LEFT_WIDTH + _output_channels.size() * GRID_SPACING, TOP_HEIGHT + GRID_SPACING * i);
 283         }
 284         lines.MoveToPoint (GRID_SPACING * 2, TOP_HEIGHT + GRID_SPACING * _input_channels.size());
 285         lines.AddLineToPoint (LEFT_WIDTH + _output_channels.size() * GRID_SPACING, TOP_HEIGHT + GRID_SPACING * _input_channels.size());
 286         gc->StrokePath (lines);
 287 }
 288
 289 void
 290 AudioMappingView::paint_indicators (wxDC& dc)
 291 {
 292         /* _{input,output}_channels and _map may not always be in sync, be careful here */
 293         size_t const output = min(_output_channels.size(), size_t(_map.output_channels()));
 294         size_t const input = min(_input_channels.size(), size_t(_map.input_channels()));
 295
 296         for (size_t x = 0; x < output; ++x) {
 297                 for (size_t y = 0; y < input; ++y) {
 298                         dc.SetBrush (*wxWHITE_BRUSH);
 299                         dc.DrawRectangle (
 300                                 wxRect(
 301                                         LEFT_WIDTH + x * GRID_SPACING + (GRID_SPACING - INDICATOR_SIZE) / 2,
 302                                         TOP_HEIGHT + y * GRID_SPACING + (GRID_SPACING - INDICATOR_SIZE) / 2,
 303                                         INDICATOR_SIZE, INDICATOR_SIZE
 304                                         )
 305                                 );
 306
 307                         float const value_dB = 20 * log10 (_map.get(y, x));
 308                         int const range = 18;
 309                         int height = 0;
 310                         if (value_dB > -range) {
 311                                 height = INDICATOR_SIZE * (1 + value_dB / range);
 312                         }
 313
 314                         dc.SetBrush (*wxTheBrushList->FindOrCreateBrush(wxColour (0, 255, 0), wxBRUSHSTYLE_SOLID));
 315                         dc.DrawRectangle (
 316                                 wxRect(
 317                                         LEFT_WIDTH + x * GRID_SPACING + (GRID_SPACING - INDICATOR_SIZE) / 2,
 318                                         TOP_HEIGHT + y * GRID_SPACING + (GRID_SPACING - INDICATOR_SIZE) / 2 + INDICATOR_SIZE - height,
 319                                         INDICATOR_SIZE, height
 320                                         )
 321                                 );
 322                 }
 323         }
 324 }
 325
 326 static
 327 void clip (wxDC& dc, wxGraphicsContext* gc, int x, int y, int w, int h)
 328 {
 329         dc.SetClippingRegion (x, y, w, h);
 330         gc->Clip (x, y, w, h);
 331 }
 332
 333 static
 334 void translate (wxDC& dc, wxGraphicsContext* gc, int x, int y)
 335 {
 336         gc->PushState ();
 337         gc->Translate (-x, -y);
 338         dc.SetLogicalOrigin (x, y);
 339 }
 340
 341 static
 342 void restore (wxDC& dc, wxGraphicsContext* gc)
 343 {
 344         dc.SetLogicalOrigin (0, 0);
 345         gc->PopState ();
 346         dc.DestroyClippingRegion ();
 347         gc->ResetClip ();
 348 }
 349
 350 void
 351 AudioMappingView::paint ()
 352 {
 353         wxPaintDC dc (_body);
 354
 355         wxGraphicsContext* gc = wxGraphicsContext::Create (dc);
 356         if (!gc) {
 357                 return;
 358         }
 359
 360         int const hs = _horizontal_scroll->GetThumbPosition ();
 361         int const vs = _vertical_scroll->GetThumbPosition ();
 362
 363         paint_static (dc, gc);
 364
 365         clip (dc, gc, LEFT_WIDTH, 0, GRID_SPACING * _output_channels.size(), GRID_SPACING * (2 + _input_channels.size()));
 366         translate (dc, gc, hs, 0);
 367         paint_column_labels (dc, gc);
 368         restore (dc, gc);
 369
 370         clip (dc, gc, 0, TOP_HEIGHT, GRID_SPACING * (3 + _output_channels.size()), GRID_SPACING * _input_channels.size() + 1);
 371         translate (dc, gc, 0, vs);
 372         paint_row_labels (dc, gc);
 373         restore (dc, gc);
 374
 375         clip (dc, gc, GRID_SPACING * 2, TOP_HEIGHT, GRID_SPACING * (1 + _output_channels.size()), GRID_SPACING * _input_channels.size() + 1);
 376         translate (dc, gc, hs, vs);
 377         paint_row_lines (gc);
 378         restore (dc, gc);
 379
 380         clip (dc, gc, LEFT_WIDTH, GRID_SPACING, GRID_SPACING * (1 + _output_channels.size()), GRID_SPACING * (1 + _input_channels.size()));
 381         translate (dc, gc, hs, vs);
 382         paint_column_lines (gc);
 383         restore (dc, gc);
 384
 385         clip (dc, gc, LEFT_WIDTH, TOP_HEIGHT, GRID_SPACING * _output_channels.size(), GRID_SPACING * _input_channels.size());
 386         translate (dc, gc, hs, vs);
 387         paint_indicators (dc);
 388         restore (dc, gc);
 389
 390         delete gc;
 391 }
 392
 393 optional<pair<int, int> >
 394 AudioMappingView::mouse_event_to_channels (wxMouseEvent& ev) const
 395 {
 396         int const x = ev.GetX() + _horizontal_scroll->GetThumbPosition();
 397         int const y = ev.GetY() + _vertical_scroll->GetThumbPosition();
 398
 399         if (x <= LEFT_WIDTH || y < TOP_HEIGHT) {
 400                 return optional<pair<int, int> >();
 401         }
 402
 403         int const input = (y - TOP_HEIGHT) / GRID_SPACING;
 404         int const output = (x - LEFT_WIDTH) / GRID_SPACING;
 405
 406         if (input >= int(_input_channels.size()) || output >= int(_output_channels.size())) {
 407                 return optional<pair<int, int> >();
 408         }
 409
 410         return make_pair (input, output);
 411 }
 412
 413 optional<string>
 414 AudioMappingView::mouse_event_to_input_group_name (wxMouseEvent& ev) const
 415 {
 416         int const x = ev.GetX() + _horizontal_scroll->GetThumbPosition();
 417         if (x < GRID_SPACING || x > (2 * GRID_SPACING)) {
 418                 return optional<string>();
 419         }
 420
 421         int y = (ev.GetY() + _vertical_scroll->GetThumbPosition() - (GRID_SPACING * 2)) / GRID_SPACING;
 422         BOOST_FOREACH (Group i, _input_groups) {
 423                 if (i.from <= y && y <= i.to) {
 424                         return i.name;
 425                 }
 426         }
 427
 428         return optional<string>();
 429 }
 430
 431 void
 432 AudioMappingView::left_down (wxMouseEvent& ev)
 433 {
 434         optional<pair<int, int> > channels = mouse_event_to_channels (ev);
 435         if (!channels) {
 436                 return;
 437         }
 438
 439         if (_map.get(channels->first, channels->second) > 0) {
 440                 _map.set (channels->first, channels->second, 0);
 441         } else {
 442                 _map.set (channels->first, channels->second, 1);
 443         }
 444
 445         map_values_changed ();
 446 }
 447
 448 void
 449 AudioMappingView::right_down (wxMouseEvent& ev)
 450 {
 451         optional<pair<int, int> > channels = mouse_event_to_channels (ev);
 452         if (!channels) {
 453                 return;
 454         }
 455
 456         _menu_input = channels->first;
 457         _menu_output = channels->second;
 458         PopupMenu (_menu, ev.GetPosition());
 459 }
 460
 461 void
 462 AudioMappingView::mouse_wheel (wxMouseEvent& ev)
 463 {
 464         if (ev.ShiftDown()) {
 465                 _horizontal_scroll->SetThumbPosition (
 466                         _horizontal_scroll->GetThumbPosition() + (ev.GetWheelRotation() > 0 ? -GRID_SPACING : GRID_SPACING)
 467                         );
 468
 469         } else {
 470                 _vertical_scroll->SetThumbPosition (
 471                         _vertical_scroll->GetThumbPosition() + (ev.GetWheelRotation() > 0 ? -GRID_SPACING : GRID_SPACING)
 472                         );
 473         }
 474         Refresh ();
 475 }
 476
 477 /** Called when any gain value has changed */
 478 void
 479 AudioMappingView::map_values_changed ()
 480 {
 481         Changed (_map);
 482         _last_tooltip_channels = optional<pair<int, int> >();
 483         Refresh ();
 484 }
 485
 486 void
 487 AudioMappingView::off ()
 488 {
 489         _map.set (_menu_input, _menu_output, 0);
 490         map_values_changed ();
 491 }
 492
 493 void
 494 AudioMappingView::full ()
 495 {
 496         _map.set (_menu_input, _menu_output, 1);
 497         map_values_changed ();
 498 }
 499
 500 void
 501 AudioMappingView::minus6dB ()
 502 {
 503         _map.set (_menu_input, _menu_output, pow (10, -6.0 / 20));
 504         map_values_changed ();
 505 }
 506
 507 void
 508 AudioMappingView::edit ()
 509 {
 510         AudioGainDialog* dialog = new AudioGainDialog (this, _menu_input, _menu_output, _map.get(_menu_input, _menu_output));
 511         if (dialog->ShowModal() == wxID_OK) {
 512                 _map.set (_menu_input, _menu_output, dialog->value ());
 513                 map_values_changed ();
 514         }
 515
 516         dialog->Destroy ();
 517 }
 518
 519 void
 520 AudioMappingView::set (AudioMapping map)
 521 {
 522         _map = map;
 523         Refresh ();
 524 }
 525
 526 void
 527 AudioMappingView::set_input_channels (vector<string> const & names)
 528 {
 529         _input_channels = names;
 530         setup ();
 531         Refresh ();
 532 }
 533
 534 void
 535 AudioMappingView::set_output_channels (vector<string> const & names)
 536 {
 537         _output_channels = names;
 538         setup ();
 539         Refresh ();
 540 }
 541
 542 void
 543 AudioMappingView::motion (wxMouseEvent& ev)
 544 {
 545         optional<pair<int, int> > channels = mouse_event_to_channels (ev);
 546         if (channels) {
 547                 if (channels != _last_tooltip_channels) {
 548                         wxString s;
 549                         float const gain = _map.get(channels->first, channels->second);
 550                         if (gain == 0) {
 551                                 s = wxString::Format (
 552                                         _("No audio will be passed from content channel %d to DCP channel %d."),
 553                                         channels->first + 1, channels->second + 1
 554                                         );
 555                         } else if (gain == 1) {
 556                                 s = wxString::Format (
 557                                         _("Audio will be passed from content channel %d to DCP channel %d unaltered."),
 558                                         channels->first + 1, channels->second + 1
 559                                         );
 560                         } else {
 561                                 float const dB = 20 * log10 (gain);
 562                                 s = wxString::Format (
 563                                         _("Audio will be passed from content channel %d to DCP channel %d with gain %.1fdB."),
 564                                         channels->first + 1, channels->second + 1, dB
 565                                         );
 566                         }
 567
 568                         SetToolTip (s + " " + _("Right click to change gain."));
 569                 }
 570         } else {
 571                 optional<string> group = mouse_event_to_input_group_name (ev);
 572                 if (group) {
 573                         SetToolTip (std_to_wx(*group));
 574                 } else {
 575                         SetToolTip ("");
 576                 }
 577         }
 578
 579         _last_tooltip_channels = channels;
 580         ev.Skip ();
 581 }
 582
 583 void
 584 AudioMappingView::set_input_groups (vector<Group> const & groups)
 585 {
 586         _input_groups = groups;
 587 }