src/wx/audio_mapping_view.cc

   1 /*
   2     Copyright (C) 2013-2020 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_minus6dB = 2,
  59         ID_0dB = 3,
  60         ID_plus3dB = 4,
  61         ID_edit = 5
  62 };
  63
  64 AudioMappingView::AudioMappingView (wxWindow* parent, wxString left_label, wxString from, wxString top_label, wxString to)
  65         : wxPanel (parent, wxID_ANY)
  66         , _menu_input (0)
  67         , _menu_output (1)
  68         , _left_label (left_label)
  69         , _from (from)
  70         , _top_label (top_label)
  71         , _to (to)
  72 {
  73         _menu = new wxMenu;
  74         _menu->Append (ID_off, _("Off"));
  75         _menu->Append (ID_minus6dB, _("-6dB"));
  76         _menu->Append (ID_0dB, _("0dB (unchanged)"));
  77         _menu->Append (ID_plus3dB, _("+3dB"));
  78         _menu->Append (ID_edit, _("Edit..."));
  79
  80         _body = new wxPanel (this, wxID_ANY);
  81         _vertical_scroll = new wxScrollBar (this, wxID_ANY, wxDefaultPosition, wxDefaultSize, wxSB_VERTICAL);
  82         _horizontal_scroll = new wxScrollBar (this, wxID_ANY);
  83
  84 #ifndef __WXOSX__
  85         SetDoubleBuffered (true);
  86 #endif
  87
  88         Bind (wxEVT_SIZE, boost::bind(&AudioMappingView::size, this, _1));
  89         Bind (wxEVT_MENU, boost::bind(&AudioMappingView::set_gain_from_menu, this, 0), ID_off);
  90         Bind (wxEVT_MENU, boost::bind(&AudioMappingView::set_gain_from_menu, this, db_to_linear(-6)), ID_minus6dB);
  91         Bind (wxEVT_MENU, boost::bind(&AudioMappingView::set_gain_from_menu, this, 1), ID_0dB);
  92         Bind (wxEVT_MENU, boost::bind(&AudioMappingView::set_gain_from_menu, this, db_to_linear(3)), ID_plus3dB);
  93         Bind (wxEVT_MENU, boost::bind(&AudioMappingView::edit, this), ID_edit);
  94         Bind (wxEVT_MOUSEWHEEL, boost::bind(&AudioMappingView::mouse_wheel, this, _1));
  95         _body->Bind (wxEVT_PAINT, boost::bind(&AudioMappingView::paint, this));
  96         _body->Bind (wxEVT_LEFT_DOWN, boost::bind(&AudioMappingView::left_down, this, _1));
  97         _body->Bind (wxEVT_RIGHT_DOWN, boost::bind(&AudioMappingView::right_down, this, _1));
  98         _body->Bind (wxEVT_MOTION, boost::bind(&AudioMappingView::motion, this, _1));
  99         _vertical_scroll->Bind (wxEVT_SCROLL_TOP, boost::bind(&AudioMappingView::scroll, this));
 100         _vertical_scroll->Bind (wxEVT_SCROLL_BOTTOM, boost::bind(&AudioMappingView::scroll, this));
 101         _vertical_scroll->Bind (wxEVT_SCROLL_LINEUP, boost::bind(&AudioMappingView::scroll, this));
 102         _vertical_scroll->Bind (wxEVT_SCROLL_LINEDOWN, boost::bind(&AudioMappingView::scroll, this));
 103         _vertical_scroll->Bind (wxEVT_SCROLL_PAGEUP, boost::bind(&AudioMappingView::scroll, this));
 104         _vertical_scroll->Bind (wxEVT_SCROLL_PAGEDOWN, boost::bind(&AudioMappingView::scroll, this));
 105         _vertical_scroll->Bind (wxEVT_SCROLL_THUMBTRACK, boost::bind(&AudioMappingView::scroll, this));
 106         _vertical_scroll->Bind (wxEVT_SCROLL_THUMBRELEASE, boost::bind(&AudioMappingView::scroll, this));
 107         _horizontal_scroll->Bind (wxEVT_SCROLL_TOP, boost::bind(&AudioMappingView::scroll, this));
 108         _horizontal_scroll->Bind (wxEVT_SCROLL_BOTTOM, boost::bind(&AudioMappingView::scroll, this));
 109         _horizontal_scroll->Bind (wxEVT_SCROLL_LINEUP, boost::bind(&AudioMappingView::scroll, this));
 110         _horizontal_scroll->Bind (wxEVT_SCROLL_LINEDOWN, boost::bind(&AudioMappingView::scroll, this));
 111         _horizontal_scroll->Bind (wxEVT_SCROLL_PAGEUP, boost::bind(&AudioMappingView::scroll, this));
 112         _horizontal_scroll->Bind (wxEVT_SCROLL_PAGEDOWN, boost::bind(&AudioMappingView::scroll, this));
 113         _horizontal_scroll->Bind (wxEVT_SCROLL_THUMBTRACK, boost::bind(&AudioMappingView::scroll, this));
 114         _horizontal_scroll->Bind (wxEVT_SCROLL_THUMBRELEASE, boost::bind(&AudioMappingView::scroll, this));
 115 }
 116
 117 void
 118 AudioMappingView::size (wxSizeEvent& ev)
 119 {
 120         setup ();
 121         ev.Skip ();
 122 }
 123
 124 void
 125 AudioMappingView::setup ()
 126 {
 127         wxSize const s = GetSize();
 128         int const w = _vertical_scroll->GetSize().GetWidth();
 129         int const h = _horizontal_scroll->GetSize().GetHeight();
 130
 131         _vertical_scroll->SetPosition (wxPoint(s.GetWidth() - w, 0));
 132         _vertical_scroll->SetSize (wxSize(w, max(0, s.GetHeight() - h)));
 133
 134         _body->SetSize (wxSize(max(0, s.GetWidth() - w), max(0, s.GetHeight() - h)));
 135
 136         _horizontal_scroll->SetPosition (wxPoint(0, s.GetHeight() - h));
 137         _horizontal_scroll->SetSize (wxSize(max(0, s.GetWidth() - w), h));
 138
 139         _vertical_scroll->SetScrollbar (
 140                 _vertical_scroll->GetThumbPosition(),
 141                 s.GetHeight() - h - 8,
 142                 GRID_SPACING * (2 + _input_channels.size()),
 143                 GRID_SPACING,
 144                 true
 145                 );
 146
 147         _horizontal_scroll->SetScrollbar (
 148                 _horizontal_scroll->GetThumbPosition(),
 149                 s.GetWidth() - w - 8,
 150                 GRID_SPACING * (3 + _output_channels.size()),
 151                 GRID_SPACING,
 152                 true);
 153 }
 154
 155 void
 156 AudioMappingView::scroll ()
 157 {
 158         Refresh ();
 159 }
 160
 161 void
 162 AudioMappingView::paint_static (wxDC& dc, wxGraphicsContext* gc)
 163 {
 164         gc->SetAntialiasMode (wxANTIALIAS_DEFAULT);
 165         dc.SetFont (wxSWISS_FONT->Bold());
 166         wxCoord label_width;
 167         wxCoord label_height;
 168
 169         dc.GetTextExtent (_top_label, &label_width, &label_height);
 170         dc.DrawText (_top_label, LEFT_WIDTH + (_output_channels.size() * GRID_SPACING - label_width) / 2, (GRID_SPACING - label_height) / 2);
 171
 172         dc.GetTextExtent (_left_label, &label_width, &label_height);
 173         dc.DrawRotatedText (
 174                 _left_label,
 175                 (GRID_SPACING - label_height) / 2,
 176                 TOP_HEIGHT + (_input_channels.size() * GRID_SPACING + label_width) / 2,
 177                 90
 178                 );
 179
 180         dc.SetFont (*wxSWISS_FONT);
 181         gc->SetPen (*wxBLACK_PEN);
 182 }
 183
 184 void
 185 AudioMappingView::paint_column_labels (wxDC& dc, wxGraphicsContext* gc)
 186 {
 187         wxCoord label_width;
 188         wxCoord label_height;
 189         int N = 0;
 190         BOOST_FOREACH (string i, _output_channels) {
 191                 dc.GetTextExtent (std_to_wx(i), &label_width, &label_height);
 192                 dc.DrawText (std_to_wx(i), LEFT_WIDTH + GRID_SPACING * N + (GRID_SPACING - label_width) / 2, GRID_SPACING + (GRID_SPACING - label_height) / 2);
 193                 ++N;
 194         }
 195
 196         wxGraphicsPath lines = gc->CreatePath ();
 197         lines.MoveToPoint (LEFT_WIDTH, GRID_SPACING);
 198         lines.AddLineToPoint (LEFT_WIDTH + _output_channels.size() * GRID_SPACING, GRID_SPACING);
 199         lines.MoveToPoint (LEFT_WIDTH, GRID_SPACING * 2);
 200         lines.AddLineToPoint (LEFT_WIDTH + _output_channels.size() * GRID_SPACING, GRID_SPACING * 2);
 201         gc->StrokePath (lines);
 202 }
 203
 204 void
 205 AudioMappingView::paint_column_lines (wxGraphicsContext* gc)
 206 {
 207         wxGraphicsPath lines = gc->CreatePath ();
 208         for (size_t i = 0; i < _output_channels.size(); ++i) {
 209                 lines.MoveToPoint    (LEFT_WIDTH + GRID_SPACING * i, GRID_SPACING);
 210                 lines.AddLineToPoint (LEFT_WIDTH + GRID_SPACING * i, TOP_HEIGHT + _input_channels.size() * GRID_SPACING);
 211         }
 212         lines.MoveToPoint    (LEFT_WIDTH + GRID_SPACING * _output_channels.size(), GRID_SPACING);
 213         lines.AddLineToPoint (LEFT_WIDTH + GRID_SPACING * _output_channels.size(), TOP_HEIGHT + _input_channels.size() * GRID_SPACING);
 214         gc->StrokePath (lines);
 215 }
 216
 217 void
 218 AudioMappingView::paint_row_labels (wxDC& dc, wxGraphicsContext* gc)
 219 {
 220         wxCoord label_width;
 221         wxCoord label_height;
 222         wxGraphicsPath lines = gc->CreatePath ();
 223
 224         /* Row channel labels */
 225
 226         int N = 0;
 227         BOOST_FOREACH (string i, _input_channels) {
 228                 dc.GetTextExtent (std_to_wx(i), &label_width, &label_height);
 229                 dc.DrawText (std_to_wx(i), GRID_SPACING * 2 + (GRID_SPACING - label_width) / 2, TOP_HEIGHT + GRID_SPACING * N + (GRID_SPACING - label_height) / 2);
 230                 ++N;
 231         }
 232
 233         /* Vertical lines on the left */
 234
 235         for (int i = 1; i < 3; ++i) {
 236                 lines.MoveToPoint    (GRID_SPACING * i, TOP_HEIGHT);
 237                 lines.AddLineToPoint (GRID_SPACING * i, TOP_HEIGHT + _input_channels.size() * GRID_SPACING);
 238         }
 239
 240         /* Group labels and lines */
 241
 242         int y = TOP_HEIGHT;
 243         BOOST_FOREACH (Group i, _input_groups) {
 244                 int const height = (i.to - i.from + 1) * GRID_SPACING;
 245                 dc.GetTextExtent (std_to_wx(i.name), &label_width, &label_height);
 246                 if (label_width > height) {
 247                         label_width = height - 8;
 248                 }
 249
 250                 {
 251                         int yp = y;
 252                         if ((yp - 2 * GRID_SPACING) < dc.GetLogicalOrigin().y) {
 253                                 yp += dc.GetLogicalOrigin().y;
 254                         }
 255
 256                         dc.DrawRotatedText (
 257                                 std_to_wx(i.name),
 258                                 GRID_SPACING + (GRID_SPACING - label_height) / 2,
 259                                 y + (height + label_width) / 2,
 260                                 90
 261                                 );
 262                 }
 263
 264                 lines.MoveToPoint    (GRID_SPACING,     y);
 265                 lines.AddLineToPoint (GRID_SPACING * 2, y);
 266                 y += height;
 267         }
 268
 269         lines.MoveToPoint    (GRID_SPACING,     y);
 270         lines.AddLineToPoint (GRID_SPACING * 2, y);
 271
 272         gc->StrokePath (lines);
 273 }
 274
 275 void
 276 AudioMappingView::paint_row_lines (wxGraphicsContext* gc)
 277 {
 278         wxGraphicsPath lines = gc->CreatePath ();
 279         for (size_t i = 0; i < _input_channels.size(); ++i) {
 280                 lines.MoveToPoint (GRID_SPACING * 2, TOP_HEIGHT + GRID_SPACING * i);
 281                 lines.AddLineToPoint (LEFT_WIDTH + _output_channels.size() * GRID_SPACING, TOP_HEIGHT + GRID_SPACING * i);
 282         }
 283         lines.MoveToPoint (GRID_SPACING * 2, TOP_HEIGHT + GRID_SPACING * _input_channels.size());
 284         lines.AddLineToPoint (LEFT_WIDTH + _output_channels.size() * GRID_SPACING, TOP_HEIGHT + GRID_SPACING * _input_channels.size());
 285         gc->StrokePath (lines);
 286 }
 287
 288 void
 289 AudioMappingView::paint_indicators (wxDC& dc)
 290 {
 291         /* _{input,output}_channels and _map may not always be in sync, be careful here */
 292         size_t const output = min(_output_channels.size(), size_t(_map.output_channels()));
 293         size_t const input = min(_input_channels.size(), size_t(_map.input_channels()));
 294
 295         for (size_t x = 0; x < output; ++x) {
 296                 for (size_t y = 0; y < input; ++y) {
 297                         dc.SetBrush (*wxWHITE_BRUSH);
 298                         dc.DrawRectangle (
 299                                 wxRect(
 300                                         LEFT_WIDTH + x * GRID_SPACING + (GRID_SPACING - INDICATOR_SIZE) / 2,
 301                                         TOP_HEIGHT + y * GRID_SPACING + (GRID_SPACING - INDICATOR_SIZE) / 2,
 302                                         INDICATOR_SIZE, INDICATOR_SIZE
 303                                         )
 304                                 );
 305
 306                         float const value_dB = linear_to_db(_map.get(y, x));
 307                         wxColour const colour = value_dB <= 0 ? wxColour(0, 255, 0) : wxColour(255, 150, 0);
 308                         int const range = 18;
 309                         int height = 0;
 310                         if (value_dB > -range) {
 311                                 height = min(INDICATOR_SIZE, static_cast<int>(INDICATOR_SIZE * (1 + value_dB / range)));
 312                         }
 313
 314                         dc.SetBrush (*wxTheBrushList->FindOrCreateBrush(colour, 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 (
 366                 dc, gc,
 367                 LEFT_WIDTH,
 368                 0,
 369                 GRID_SPACING * _output_channels.size(),
 370                 GRID_SPACING * (2 + _input_channels.size())
 371              );
 372         translate (dc, gc, hs, 0);
 373         paint_column_labels (dc, gc);
 374         restore (dc, gc);
 375
 376         clip (
 377                 dc, gc,
 378                 0,
 379                 TOP_HEIGHT,
 380                 GRID_SPACING * 3,
 381                 min(int(GRID_SPACING * _input_channels.size()), GetSize().GetHeight() - TOP_HEIGHT)
 382              );
 383         translate (dc, gc, 0, vs);
 384         paint_row_labels (dc, gc);
 385         restore (dc, gc);
 386
 387         clip (
 388                 dc, gc,
 389                 GRID_SPACING * 2,
 390                 TOP_HEIGHT,
 391                 GRID_SPACING * (1 + _output_channels.size()),
 392                 min(int(GRID_SPACING * (2 + _input_channels.size())), GetSize().GetHeight() - TOP_HEIGHT)
 393              );
 394         translate (dc, gc, hs, vs);
 395         paint_row_lines (gc);
 396         restore (dc, gc);
 397
 398         clip (
 399                 dc, gc,
 400                 LEFT_WIDTH,
 401                 GRID_SPACING,
 402                 GRID_SPACING * (1 + _output_channels.size()),
 403                 min(int(GRID_SPACING * (1 + _input_channels.size())), GetSize().GetHeight() - GRID_SPACING)
 404              );
 405         translate (dc, gc, hs, vs);
 406         paint_column_lines (gc);
 407         restore (dc, gc);
 408
 409         clip (
 410                 dc, gc,
 411                 LEFT_WIDTH,
 412                 TOP_HEIGHT,
 413                 GRID_SPACING * _output_channels.size(),
 414                 min(int(GRID_SPACING * _input_channels.size()), GetSize().GetHeight() - TOP_HEIGHT)
 415              );
 416         translate (dc, gc, hs, vs);
 417         paint_indicators (dc);
 418         restore (dc, gc);
 419
 420         delete gc;
 421 }
 422
 423 optional<pair<int, int> >
 424 AudioMappingView::mouse_event_to_channels (wxMouseEvent& ev) const
 425 {
 426         int const x = ev.GetX() + _horizontal_scroll->GetThumbPosition();
 427         int const y = ev.GetY() + _vertical_scroll->GetThumbPosition();
 428
 429         if (x <= LEFT_WIDTH || y < TOP_HEIGHT) {
 430                 return optional<pair<int, int> >();
 431         }
 432
 433         int const input = (y - TOP_HEIGHT) / GRID_SPACING;
 434         int const output = (x - LEFT_WIDTH) / GRID_SPACING;
 435
 436         if (input >= int(_input_channels.size()) || output >= int(_output_channels.size())) {
 437                 return optional<pair<int, int> >();
 438         }
 439
 440         return make_pair (input, output);
 441 }
 442
 443 optional<string>
 444 AudioMappingView::mouse_event_to_input_group_name (wxMouseEvent& ev) const
 445 {
 446         int const x = ev.GetX() + _horizontal_scroll->GetThumbPosition();
 447         if (x < GRID_SPACING || x > (2 * GRID_SPACING)) {
 448                 return optional<string>();
 449         }
 450
 451         int y = (ev.GetY() + _vertical_scroll->GetThumbPosition() - (GRID_SPACING * 2)) / GRID_SPACING;
 452         BOOST_FOREACH (Group i, _input_groups) {
 453                 if (i.from <= y && y <= i.to) {
 454                         return i.name;
 455                 }
 456         }
 457
 458         return optional<string>();
 459 }
 460
 461 void
 462 AudioMappingView::left_down (wxMouseEvent& ev)
 463 {
 464         optional<pair<int, int> > channels = mouse_event_to_channels (ev);
 465         if (!channels) {
 466                 return;
 467         }
 468
 469         if (_map.get(channels->first, channels->second) > 0) {
 470                 _map.set (channels->first, channels->second, 0);
 471         } else {
 472                 _map.set (channels->first, channels->second, 1);
 473         }
 474
 475         map_values_changed ();
 476 }
 477
 478 void
 479 AudioMappingView::right_down (wxMouseEvent& ev)
 480 {
 481         optional<pair<int, int> > channels = mouse_event_to_channels (ev);
 482         if (!channels) {
 483                 return;
 484         }
 485
 486         _menu_input = channels->first;
 487         _menu_output = channels->second;
 488         PopupMenu (_menu, ev.GetPosition());
 489 }
 490
 491 void
 492 AudioMappingView::mouse_wheel (wxMouseEvent& ev)
 493 {
 494         if (ev.ShiftDown()) {
 495                 _horizontal_scroll->SetThumbPosition (
 496                         _horizontal_scroll->GetThumbPosition() + (ev.GetWheelRotation() > 0 ? -GRID_SPACING : GRID_SPACING)
 497                         );
 498
 499         } else {
 500                 _vertical_scroll->SetThumbPosition (
 501                         _vertical_scroll->GetThumbPosition() + (ev.GetWheelRotation() > 0 ? -GRID_SPACING : GRID_SPACING)
 502                         );
 503         }
 504         Refresh ();
 505 }
 506
 507 /** Called when any gain value has changed */
 508 void
 509 AudioMappingView::map_values_changed ()
 510 {
 511         Changed (_map);
 512         _last_tooltip_channels = optional<pair<int, int> >();
 513         Refresh ();
 514 }
 515
 516 void
 517 AudioMappingView::set_gain_from_menu (double linear)
 518 {
 519         _map.set (_menu_input, _menu_output, linear);
 520         map_values_changed ();
 521 }
 522
 523 void
 524 AudioMappingView::edit ()
 525 {
 526         AudioGainDialog* dialog = new AudioGainDialog (this, _menu_input, _menu_output, _map.get(_menu_input, _menu_output));
 527         if (dialog->ShowModal() == wxID_OK) {
 528                 _map.set (_menu_input, _menu_output, dialog->value ());
 529                 map_values_changed ();
 530         }
 531
 532         dialog->Destroy ();
 533 }
 534
 535 void
 536 AudioMappingView::set (AudioMapping map)
 537 {
 538         _map = map;
 539         Refresh ();
 540 }
 541
 542 void
 543 AudioMappingView::set_input_channels (vector<string> const & names)
 544 {
 545         _input_channels = names;
 546         setup ();
 547         Refresh ();
 548 }
 549
 550 void
 551 AudioMappingView::set_output_channels (vector<string> const & names)
 552 {
 553         _output_channels = names;
 554         setup ();
 555         Refresh ();
 556 }
 557
 558 wxString
 559 AudioMappingView::safe_input_channel_name (int n) const
 560 {
 561         if (n >= int(_input_channels.size())) {
 562                 return wxString::Format ("%d", n + 1);
 563         }
 564
 565         optional<wxString> group;
 566         BOOST_FOREACH (Group i, _input_groups) {
 567                 if (i.from <= n && n <= i.to) {
 568                         group = std_to_wx (i.name);
 569                 }
 570         }
 571
 572         if (group && !group->IsEmpty()) {
 573                 return wxString::Format ("%s/%s", group->data(), std_to_wx(_input_channels[n]).data());
 574         }
 575
 576         return std_to_wx(_input_channels[n]);
 577 }
 578
 579 wxString
 580 AudioMappingView::safe_output_channel_name (int n) const
 581 {
 582         if (n >= int(_output_channels.size())) {
 583                 return wxString::Format ("%d", n + 1);
 584         }
 585
 586         return std_to_wx(_output_channels[n]);
 587 }
 588
 589 void
 590 AudioMappingView::motion (wxMouseEvent& ev)
 591 {
 592         optional<pair<int, int> > channels = mouse_event_to_channels (ev);
 593         if (channels) {
 594                 if (channels != _last_tooltip_channels) {
 595                         wxString s;
 596                         float const gain = _map.get(channels->first, channels->second);
 597                         if (gain == 0) {
 598                                 s = wxString::Format (
 599                                         _("No audio will be passed from %s channel '%s' to %s channel '%s'."),
 600                                         _from,
 601                                         safe_input_channel_name(channels->first),
 602                                         _to,
 603                                         safe_output_channel_name(channels->second)
 604                                         );
 605                         } else if (gain == 1) {
 606                                 s = wxString::Format (
 607                                         _("Audio will be passed from %s channel %s to %s channel %s unaltered."),
 608                                         _from,
 609                                         safe_input_channel_name(channels->first),
 610                                         _to,
 611                                         safe_output_channel_name(channels->second)
 612                                         );
 613                         } else {
 614                                 float const dB = linear_to_db(gain);
 615                                 s = wxString::Format (
 616                                         _("Audio will be passed from %s channel %s to %s channel %s with gain %.1fdB."),
 617                                         _from,
 618                                         safe_input_channel_name(channels->first),
 619                                         _to,
 620                                         safe_output_channel_name(channels->second),
 621                                         dB
 622                                         );
 623                         }
 624
 625                         SetToolTip (s + " " + _("Right click to change gain."));
 626                 }
 627         } else {
 628                 optional<string> group = mouse_event_to_input_group_name (ev);
 629                 if (group) {
 630                         SetToolTip (std_to_wx(*group));
 631                 } else {
 632                         SetToolTip ("");
 633                 }
 634         }
 635
 636         _last_tooltip_channels = channels;
 637         ev.Skip ();
 638 }
 639
 640 void
 641 AudioMappingView::set_input_groups (vector<Group> const & groups)
 642 {
 643         _input_groups = groups;
 644 }