src/airport_gui.cpp

   1 /*
   2  * This file is part of OpenTTD.
   3  * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
   4  * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
   5  * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
   6  */
   7
   8 /** @file airport_gui.cpp The GUI for airports. */
   9
  10 #include "stdafx.h"
  11 #include "window_gui.h"
  12 #include "station_gui.h"
  13 #include "terraform_gui.h"
  14 #include "sound_func.h"
  15 #include "window_func.h"
  16 #include "strings_func.h"
  17 #include "viewport_func.h"
  18 #include "company_func.h"
  19 #include "tilehighlight_func.h"
  20 #include "company_base.h"
  21 #include "station_type.h"
  22 #include "newgrf_airport.h"
  23 #include "newgrf_callbacks.h"
  24 #include "widgets/dropdown_type.h"
  25 #include "core/geometry_func.hpp"
  26 #include "hotkeys.h"
  27 #include "vehicle_func.h"
  28 #include "gui.h"
  29
  30 #include "widgets/airport_widget.h"
  31
  32 #include "safeguards.h"
  33
  34
  35 static AirportClassID _selected_airport_class; ///< the currently visible airport class
  36 static int _selected_airport_index;            ///< the index of the selected airport in the current class or -1
  37 static byte _selected_airport_layout;          ///< selected airport layout number.
  38
  39 static void ShowBuildAirportPicker(Window *parent);
  40
  41 SpriteID GetCustomAirportSprite(const AirportSpec *as, byte layout);
  42
  43 void CcBuildAirport(const CommandCost &result, TileIndex tile, uint32 p1, uint32 p2, uint32 cmd)
  44 {
  45         if (result.Failed()) return;
  46
  47         if (_settings_client.sound.confirm) SndPlayTileFx(SND_1F_CONSTRUCTION_OTHER, tile);
  48         if (!_settings_client.gui.persistent_buildingtools) ResetObjectToPlace();
  49 }
  50
  51 /**
  52  * Place an airport.
  53  * @param tile Position to put the new airport.
  54  */
  55 static void PlaceAirport(TileIndex tile)
  56 {
  57         if (_selected_airport_index == -1) return;
  58         uint32 p2 = _ctrl_pressed;
  59         SB(p2, 16, 16, INVALID_STATION); // no station to join
  60
  61         uint32 p1 = AirportClass::Get(_selected_airport_class)->GetSpec(_selected_airport_index)->GetIndex();
  62         p1 |= _selected_airport_layout << 8;
  63         CommandContainer cmdcont = { tile, p1, p2, CMD_BUILD_AIRPORT | CMD_MSG(STR_ERROR_CAN_T_BUILD_AIRPORT_HERE), CcBuildAirport, "" };
  64         ShowSelectStationIfNeeded(cmdcont, TileArea(tile, _thd.size.x / TILE_SIZE, _thd.size.y / TILE_SIZE));
  65 }
  66
  67 /** Airport build toolbar window handler. */
  68 struct BuildAirToolbarWindow : Window {
  69         int last_user_action; // Last started user action.
  70
  71         BuildAirToolbarWindow(WindowDesc *desc, WindowNumber window_number) : Window(desc)
  72         {
  73                 this->InitNested(window_number);
  74                 this->OnInvalidateData();
  75                 if (_settings_client.gui.link_terraform_toolbar) ShowTerraformToolbar(this);
  76                 this->last_user_action = WIDGET_LIST_END;
  77         }
  78
  79         ~BuildAirToolbarWindow()
  80         {
  81                 if (this->IsWidgetLowered(WID_AT_AIRPORT)) SetViewportCatchmentStation(nullptr, true);
  82                 if (_settings_client.gui.link_terraform_toolbar) DeleteWindowById(WC_SCEN_LAND_GEN, 0, false);
  83         }
  84
  85         /**
  86          * Some data on this window has become invalid.
  87          * @param data Information about the changed data.
  88          * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
  89          */
  90         void OnInvalidateData(int data = 0, bool gui_scope = true) override
  91         {
  92                 if (!gui_scope) return;
  93
  94                 bool can_build = CanBuildVehicleInfrastructure(VEH_AIRCRAFT);
  95                 this->SetWidgetsDisabledState(!can_build,
  96                         WID_AT_AIRPORT,
  97                         WIDGET_LIST_END);
  98                 if (!can_build) {
  99                         DeleteWindowById(WC_BUILD_STATION, TRANSPORT_AIR);
 100
 101                         /* Show in the tooltip why this button is disabled. */
 102                         this->GetWidget<NWidgetCore>(WID_AT_AIRPORT)->SetToolTip(STR_TOOLBAR_DISABLED_NO_VEHICLE_AVAILABLE);
 103                 } else {
 104                         this->GetWidget<NWidgetCore>(WID_AT_AIRPORT)->SetToolTip(STR_TOOLBAR_AIRCRAFT_BUILD_AIRPORT_TOOLTIP);
 105                 }
 106         }
 107
 108         void OnClick(Point pt, int widget, int click_count) override
 109         {
 110                 switch (widget) {
 111                         case WID_AT_AIRPORT:
 112                                 if (HandlePlacePushButton(this, WID_AT_AIRPORT, SPR_CURSOR_AIRPORT, HT_RECT)) {
 113                                         ShowBuildAirportPicker(this);
 114                                         this->last_user_action = widget;
 115                                 }
 116                                 break;
 117
 118                         case WID_AT_DEMOLISH:
 119                                 HandlePlacePushButton(this, WID_AT_DEMOLISH, ANIMCURSOR_DEMOLISH, HT_RECT | HT_DIAGONAL);
 120                                 this->last_user_action = widget;
 121                                 break;
 122
 123                         default: break;
 124                 }
 125         }
 126
 127
 128         void OnPlaceObject(Point pt, TileIndex tile) override
 129         {
 130                 switch (this->last_user_action) {
 131                         case WID_AT_AIRPORT:
 132                                 PlaceAirport(tile);
 133                                 break;
 134
 135                         case WID_AT_DEMOLISH:
 136                                 PlaceProc_DemolishArea(tile);
 137                                 break;
 138
 139                         default: NOT_REACHED();
 140                 }
 141         }
 142
 143         void OnPlaceDrag(ViewportPlaceMethod select_method, ViewportDragDropSelectionProcess select_proc, Point pt) override
 144         {
 145                 VpSelectTilesWithMethod(pt.x, pt.y, select_method);
 146         }
 147
 148         void OnPlaceMouseUp(ViewportPlaceMethod select_method, ViewportDragDropSelectionProcess select_proc, Point pt, TileIndex start_tile, TileIndex end_tile) override
 149         {
 150                 if (pt.x != -1 && select_proc == DDSP_DEMOLISH_AREA) {
 151                         GUIPlaceProcDragXY(select_proc, start_tile, end_tile);
 152                 }
 153         }
 154
 155         void OnPlaceObjectAbort() override
 156         {
 157                 if (this->IsWidgetLowered(WID_AT_AIRPORT)) SetViewportCatchmentStation(nullptr, true);
 158
 159                 this->RaiseButtons();
 160
 161                 DeleteWindowById(WC_BUILD_STATION, TRANSPORT_AIR);
 162                 DeleteWindowById(WC_SELECT_STATION, 0);
 163         }
 164
 165         static HotkeyList hotkeys;
 166 };
 167
 168 /**
 169  * Handler for global hotkeys of the BuildAirToolbarWindow.
 170  * @param hotkey Hotkey
 171  * @return ES_HANDLED if hotkey was accepted.
 172  */
 173 static EventState AirportToolbarGlobalHotkeys(int hotkey)
 174 {
 175         if (_game_mode != GM_NORMAL) return ES_NOT_HANDLED;
 176         Window *w = ShowBuildAirToolbar();
 177         if (w == nullptr) return ES_NOT_HANDLED;
 178         return w->OnHotkey(hotkey);
 179 }
 180
 181 static Hotkey airtoolbar_hotkeys[] = {
 182         Hotkey('1', "airport", WID_AT_AIRPORT),
 183         Hotkey('2', "demolish", WID_AT_DEMOLISH),
 184         HOTKEY_LIST_END
 185 };
 186 HotkeyList BuildAirToolbarWindow::hotkeys("airtoolbar", airtoolbar_hotkeys, AirportToolbarGlobalHotkeys);
 187
 188 static const NWidgetPart _nested_air_toolbar_widgets[] = {
 189         NWidget(NWID_HORIZONTAL),
 190                 NWidget(WWT_CLOSEBOX, COLOUR_DARK_GREEN),
 191                 NWidget(WWT_CAPTION, COLOUR_DARK_GREEN), SetDataTip(STR_TOOLBAR_AIRCRAFT_CAPTION, STR_TOOLTIP_WINDOW_TITLE_DRAG_THIS),
 192                 NWidget(WWT_STICKYBOX, COLOUR_DARK_GREEN),
 193         EndContainer(),
 194         NWidget(NWID_HORIZONTAL),
 195                 NWidget(WWT_IMGBTN, COLOUR_DARK_GREEN, WID_AT_AIRPORT), SetFill(0, 1), SetMinimalSize(42, 22), SetDataTip(SPR_IMG_AIRPORT, STR_TOOLBAR_AIRCRAFT_BUILD_AIRPORT_TOOLTIP),
 196                 NWidget(WWT_PANEL, COLOUR_DARK_GREEN), SetMinimalSize(4, 22), SetFill(1, 1), EndContainer(),
 197                 NWidget(WWT_IMGBTN, COLOUR_DARK_GREEN, WID_AT_DEMOLISH), SetFill(0, 1), SetMinimalSize(22, 22), SetDataTip(SPR_IMG_DYNAMITE, STR_TOOLTIP_DEMOLISH_BUILDINGS_ETC),
 198         EndContainer(),
 199 };
 200
 201 static WindowDesc _air_toolbar_desc(
 202         WDP_ALIGN_TOOLBAR, "toolbar_air", 0, 0,
 203         WC_BUILD_TOOLBAR, WC_NONE,
 204         WDF_CONSTRUCTION,
 205         _nested_air_toolbar_widgets, lengthof(_nested_air_toolbar_widgets),
 206         &BuildAirToolbarWindow::hotkeys
 207 );
 208
 209 /**
 210  * Open the build airport toolbar window
 211  *
 212  * If the terraform toolbar is linked to the toolbar, that window is also opened.
 213  *
 214  * @return newly opened airport toolbar, or nullptr if the toolbar could not be opened.
 215  */
 216 Window *ShowBuildAirToolbar()
 217 {
 218         if (!Company::IsValidID(_local_company)) return nullptr;
 219
 220         DeleteWindowByClass(WC_BUILD_TOOLBAR);
 221         return AllocateWindowDescFront<BuildAirToolbarWindow>(&_air_toolbar_desc, TRANSPORT_AIR);
 222 }
 223
 224 class BuildAirportWindow : public PickerWindowBase {
 225         SpriteID preview_sprite; ///< Cached airport preview sprite.
 226         int line_height;
 227         Scrollbar *vscroll;
 228
 229         /** Build a dropdown list of available airport classes */
 230         static DropDownList BuildAirportClassDropDown()
 231         {
 232                 DropDownList list;
 233
 234                 for (uint i = 0; i < AirportClass::GetClassCount(); i++) {
 235                         list.emplace_back(new DropDownListStringItem(AirportClass::Get((AirportClassID)i)->name, i, false));
 236                 }
 237
 238                 return list;
 239         }
 240
 241 public:
 242         BuildAirportWindow(WindowDesc *desc, Window *parent) : PickerWindowBase(desc, parent)
 243         {
 244                 this->CreateNestedTree();
 245
 246                 this->vscroll = this->GetScrollbar(WID_AP_SCROLLBAR);
 247                 this->vscroll->SetCapacity(5);
 248                 this->vscroll->SetPosition(0);
 249
 250                 this->FinishInitNested(TRANSPORT_AIR);
 251
 252                 this->SetWidgetLoweredState(WID_AP_BTN_DONTHILIGHT, !_settings_client.gui.station_show_coverage);
 253                 this->SetWidgetLoweredState(WID_AP_BTN_DOHILIGHT, _settings_client.gui.station_show_coverage);
 254                 this->OnInvalidateData();
 255
 256                 /* Ensure airport class is valid (changing NewGRFs). */
 257                 _selected_airport_class = Clamp(_selected_airport_class, APC_BEGIN, (AirportClassID)(AirportClass::GetClassCount() - 1));
 258                 const AirportClass *ac = AirportClass::Get(_selected_airport_class);
 259                 this->vscroll->SetCount(ac->GetSpecCount());
 260
 261                 /* Ensure the airport index is valid for this class (changing NewGRFs). */
 262                 _selected_airport_index = Clamp(_selected_airport_index, -1, ac->GetSpecCount() - 1);
 263
 264                 /* Only when no valid airport was selected, we want to select the first airport. */
 265                 bool selectFirstAirport = true;
 266                 if (_selected_airport_index != -1) {
 267                         const AirportSpec *as = ac->GetSpec(_selected_airport_index);
 268                         if (as->IsAvailable()) {
 269                                 /* Ensure the airport layout is valid. */
 270                                 _selected_airport_layout = Clamp(_selected_airport_layout, 0, as->num_table - 1);
 271                                 selectFirstAirport = false;
 272                                 this->UpdateSelectSize();
 273                         }
 274                 }
 275
 276                 if (selectFirstAirport) this->SelectFirstAvailableAirport(true);
 277         }
 278
 279         virtual ~BuildAirportWindow()
 280         {
 281                 DeleteWindowById(WC_SELECT_STATION, 0);
 282         }
 283
 284         void SetStringParameters(int widget) const override
 285         {
 286                 switch (widget) {
 287                         case WID_AP_CLASS_DROPDOWN:
 288                                 SetDParam(0, AirportClass::Get(_selected_airport_class)->name);
 289                                 break;
 290
 291                         case WID_AP_LAYOUT_NUM:
 292                                 SetDParam(0, STR_EMPTY);
 293                                 if (_selected_airport_index != -1) {
 294                                         const AirportSpec *as = AirportClass::Get(_selected_airport_class)->GetSpec(_selected_airport_index);
 295                                         StringID string = GetAirportTextCallback(as, _selected_airport_layout, CBID_AIRPORT_LAYOUT_NAME);
 296                                         if (string != STR_UNDEFINED) {
 297                                                 SetDParam(0, string);
 298                                         } else if (as->num_table > 1) {
 299                                                 SetDParam(0, STR_STATION_BUILD_AIRPORT_LAYOUT_NAME);
 300                                                 SetDParam(1, _selected_airport_layout + 1);
 301                                         }
 302                                 }
 303                                 break;
 304
 305                         default: break;
 306                 }
 307         }
 308
 309         void UpdateWidgetSize(int widget, Dimension *size, const Dimension &padding, Dimension *fill, Dimension *resize) override
 310         {
 311                 switch (widget) {
 312                         case WID_AP_CLASS_DROPDOWN: {
 313                                 Dimension d = {0, 0};
 314                                 for (uint i = 0; i < AirportClass::GetClassCount(); i++) {
 315                                         SetDParam(0, AirportClass::Get((AirportClassID)i)->name);
 316                                         d = maxdim(d, GetStringBoundingBox(STR_BLACK_STRING));
 317                                 }
 318                                 d.width += padding.width;
 319                                 d.height += padding.height;
 320                                 *size = maxdim(*size, d);
 321                                 break;
 322                         }
 323
 324                         case WID_AP_AIRPORT_LIST: {
 325                                 for (int i = 0; i < NUM_AIRPORTS; i++) {
 326                                         const AirportSpec *as = AirportSpec::Get(i);
 327                                         if (!as->enabled) continue;
 328
 329                                         size->width = std::max(size->width, GetStringBoundingBox(as->name).width);
 330                                 }
 331
 332                                 this->line_height = FONT_HEIGHT_NORMAL + WD_MATRIX_TOP + WD_MATRIX_BOTTOM;
 333                                 size->height = 5 * this->line_height;
 334                                 break;
 335                         }
 336
 337                         case WID_AP_AIRPORT_SPRITE:
 338                                 for (int i = 0; i < NUM_AIRPORTS; i++) {
 339                                         const AirportSpec *as = AirportSpec::Get(i);
 340                                         if (!as->enabled) continue;
 341                                         for (byte layout = 0; layout < as->num_table; layout++) {
 342                                                 SpriteID sprite = GetCustomAirportSprite(as, layout);
 343                                                 if (sprite != 0) {
 344                                                         Dimension d = GetSpriteSize(sprite);
 345                                                         d.width += WD_FRAMERECT_LEFT + WD_FRAMERECT_RIGHT;
 346                                                         d.height += WD_FRAMERECT_TOP + WD_FRAMERECT_BOTTOM;
 347                                                         *size = maxdim(d, *size);
 348                                                 }
 349                                         }
 350                                 }
 351                                 break;
 352
 353                         case WID_AP_EXTRA_TEXT:
 354                                 for (int i = NEW_AIRPORT_OFFSET; i < NUM_AIRPORTS; i++) {
 355                                         const AirportSpec *as = AirportSpec::Get(i);
 356                                         if (!as->enabled) continue;
 357                                         for (byte layout = 0; layout < as->num_table; layout++) {
 358                                                 StringID string = GetAirportTextCallback(as, layout, CBID_AIRPORT_ADDITIONAL_TEXT);
 359                                                 if (string == STR_UNDEFINED) continue;
 360
 361                                                 /* STR_BLACK_STRING is used to start the string with {BLACK} */
 362                                                 SetDParam(0, string);
 363                                                 Dimension d = GetStringMultiLineBoundingBox(STR_BLACK_STRING, *size);
 364                                                 *size = maxdim(d, *size);
 365                                         }
 366                                 }
 367                                 break;
 368
 369                         default: break;
 370                 }
 371         }
 372
 373         void DrawWidget(const Rect &r, int widget) const override
 374         {
 375                 switch (widget) {
 376                         case WID_AP_AIRPORT_LIST: {
 377                                 int y = r.top;
 378                                 AirportClass *apclass = AirportClass::Get(_selected_airport_class);
 379                                 for (uint i = this->vscroll->GetPosition(); this->vscroll->IsVisible(i) && i < apclass->GetSpecCount(); i++) {
 380                                         const AirportSpec *as = apclass->GetSpec(i);
 381                                         if (!as->IsAvailable()) {
 382                                                 GfxFillRect(r.left + 1, y + 1, r.right - 1, y + this->line_height - 2, PC_BLACK, FILLRECT_CHECKER);
 383                                         }
 384                                         DrawString(r.left + WD_MATRIX_LEFT, r.right - WD_MATRIX_RIGHT, y + WD_MATRIX_TOP, as->name, ((int)i == _selected_airport_index) ? TC_WHITE : TC_BLACK);
 385                                         y += this->line_height;
 386                                 }
 387                                 break;
 388                         }
 389
 390                         case WID_AP_AIRPORT_SPRITE:
 391                                 if (this->preview_sprite != 0) {
 392                                         Dimension d = GetSpriteSize(this->preview_sprite);
 393                                         DrawSprite(this->preview_sprite, COMPANY_SPRITE_COLOUR(_local_company), (r.left + r.right - d.width) / 2, (r.top + r.bottom - d.height) / 2);
 394                                 }
 395                                 break;
 396
 397                         case WID_AP_EXTRA_TEXT:
 398                                 if (_selected_airport_index != -1) {
 399                                         const AirportSpec *as = AirportClass::Get(_selected_airport_class)->GetSpec(_selected_airport_index);
 400                                         StringID string = GetAirportTextCallback(as, _selected_airport_layout, CBID_AIRPORT_ADDITIONAL_TEXT);
 401                                         if (string != STR_UNDEFINED) {
 402                                                 SetDParam(0, string);
 403                                                 DrawStringMultiLine(r.left, r.right, r.top, r.bottom, STR_BLACK_STRING);
 404                                         }
 405                                 }
 406                                 break;
 407                 }
 408         }
 409
 410         void OnPaint() override
 411         {
 412                 this->DrawWidgets();
 413
 414                 uint16 top = this->GetWidget<NWidgetBase>(WID_AP_BTN_DOHILIGHT)->pos_y + this->GetWidget<NWidgetBase>(WID_AP_BTN_DOHILIGHT)->current_y + WD_PAR_VSEP_NORMAL;
 415                 NWidgetBase *panel_nwi = this->GetWidget<NWidgetBase>(WID_AP_BOTTOMPANEL);
 416
 417                 int right = panel_nwi->pos_x +  panel_nwi->current_x;
 418                 int bottom = panel_nwi->pos_y +  panel_nwi->current_y;
 419
 420                 if (_selected_airport_index != -1) {
 421                         const AirportSpec *as = AirportClass::Get(_selected_airport_class)->GetSpec(_selected_airport_index);
 422                         int rad = _settings_game.station.modified_catchment ? as->catchment : (uint)CA_UNMODIFIED;
 423
 424                         /* only show the station (airport) noise, if the noise option is activated */
 425                         if (_settings_game.economy.station_noise_level) {
 426                                 /* show the noise of the selected airport */
 427                                 SetDParam(0, as->noise_level);
 428                                 DrawString(panel_nwi->pos_x + WD_FRAMERECT_LEFT, right - WD_FRAMERECT_RIGHT, top, STR_STATION_BUILD_NOISE);
 429                                 top += FONT_HEIGHT_NORMAL + WD_PAR_VSEP_NORMAL;
 430                         }
 431
 432                         /* strings such as 'Size' and 'Coverage Area' */
 433                         top = DrawStationCoverageAreaText(panel_nwi->pos_x + WD_FRAMERECT_LEFT, right - WD_FRAMERECT_RIGHT, top, SCT_ALL, rad, false) + WD_PAR_VSEP_NORMAL;
 434                         top = DrawStationCoverageAreaText(panel_nwi->pos_x + WD_FRAMERECT_LEFT, right - WD_FRAMERECT_RIGHT, top, SCT_ALL, rad, true) + WD_PAR_VSEP_NORMAL;
 435                 }
 436
 437                 /* Resize background if the window is too small.
 438                  * Never make the window smaller to avoid oscillating if the size change affects the acceptance.
 439                  * (This is the case, if making the window bigger moves the mouse into the window.) */
 440                 if (top > bottom) {
 441                         ResizeWindow(this, 0, top - bottom, false);
 442                 }
 443         }
 444
 445         void SelectOtherAirport(int airport_index)
 446         {
 447                 _selected_airport_index = airport_index;
 448                 _selected_airport_layout = 0;
 449
 450                 this->UpdateSelectSize();
 451                 this->SetDirty();
 452         }
 453
 454         void UpdateSelectSize()
 455         {
 456                 if (_selected_airport_index == -1) {
 457                         SetTileSelectSize(1, 1);
 458                         this->DisableWidget(WID_AP_LAYOUT_DECREASE);
 459                         this->DisableWidget(WID_AP_LAYOUT_INCREASE);
 460                 } else {
 461                         const AirportSpec *as = AirportClass::Get(_selected_airport_class)->GetSpec(_selected_airport_index);
 462                         int w = as->size_x;
 463                         int h = as->size_y;
 464                         Direction rotation = as->rotation[_selected_airport_layout];
 465                         if (rotation == DIR_E || rotation == DIR_W) Swap(w, h);
 466                         SetTileSelectSize(w, h);
 467
 468                         this->preview_sprite = GetCustomAirportSprite(as, _selected_airport_layout);
 469
 470                         this->SetWidgetDisabledState(WID_AP_LAYOUT_DECREASE, _selected_airport_layout == 0);
 471                         this->SetWidgetDisabledState(WID_AP_LAYOUT_INCREASE, _selected_airport_layout + 1 >= as->num_table);
 472
 473                         int rad = _settings_game.station.modified_catchment ? as->catchment : (uint)CA_UNMODIFIED;
 474                         if (_settings_client.gui.station_show_coverage) SetTileSelectBigSize(-rad, -rad, 2 * rad, 2 * rad);
 475                 }
 476         }
 477
 478         void OnClick(Point pt, int widget, int click_count) override
 479         {
 480                 switch (widget) {
 481                         case WID_AP_CLASS_DROPDOWN:
 482                                 ShowDropDownList(this, BuildAirportClassDropDown(), _selected_airport_class, WID_AP_CLASS_DROPDOWN);
 483                                 break;
 484
 485                         case WID_AP_AIRPORT_LIST: {
 486                                 int num_clicked = this->vscroll->GetPosition() + (pt.y - this->nested_array[widget]->pos_y) / this->line_height;
 487                                 if (num_clicked >= this->vscroll->GetCount()) break;
 488                                 const AirportSpec *as = AirportClass::Get(_selected_airport_class)->GetSpec(num_clicked);
 489                                 if (as->IsAvailable()) this->SelectOtherAirport(num_clicked);
 490                                 break;
 491                         }
 492
 493                         case WID_AP_BTN_DONTHILIGHT: case WID_AP_BTN_DOHILIGHT:
 494                                 _settings_client.gui.station_show_coverage = (widget != WID_AP_BTN_DONTHILIGHT);
 495                                 this->SetWidgetLoweredState(WID_AP_BTN_DONTHILIGHT, !_settings_client.gui.station_show_coverage);
 496                                 this->SetWidgetLoweredState(WID_AP_BTN_DOHILIGHT, _settings_client.gui.station_show_coverage);
 497                                 this->SetDirty();
 498                                 if (_settings_client.sound.click_beep) SndPlayFx(SND_15_BEEP);
 499                                 this->UpdateSelectSize();
 500                                 SetViewportCatchmentStation(nullptr, true);
 501                                 break;
 502
 503                         case WID_AP_LAYOUT_DECREASE:
 504                                 _selected_airport_layout--;
 505                                 this->UpdateSelectSize();
 506                                 this->SetDirty();
 507                                 break;
 508
 509                         case WID_AP_LAYOUT_INCREASE:
 510                                 _selected_airport_layout++;
 511                                 this->UpdateSelectSize();
 512                                 this->SetDirty();
 513                                 break;
 514                 }
 515         }
 516
 517         /**
 518          * Select the first available airport.
 519          * @param change_class If true, change the class if no airport in the current
 520          *   class is available.
 521          */
 522         void SelectFirstAvailableAirport(bool change_class)
 523         {
 524                 /* First try to select an airport in the selected class. */
 525                 AirportClass *sel_apclass = AirportClass::Get(_selected_airport_class);
 526                 for (uint i = 0; i < sel_apclass->GetSpecCount(); i++) {
 527                         const AirportSpec *as = sel_apclass->GetSpec(i);
 528                         if (as->IsAvailable()) {
 529                                 this->SelectOtherAirport(i);
 530                                 return;
 531                         }
 532                 }
 533                 if (change_class) {
 534                         /* If that fails, select the first available airport
 535                          * from a random class. */
 536                         for (AirportClassID j = APC_BEGIN; j < APC_MAX; j++) {
 537                                 AirportClass *apclass = AirportClass::Get(j);
 538                                 for (uint i = 0; i < apclass->GetSpecCount(); i++) {
 539                                         const AirportSpec *as = apclass->GetSpec(i);
 540                                         if (as->IsAvailable()) {
 541                                                 _selected_airport_class = j;
 542                                                 this->SelectOtherAirport(i);
 543                                                 return;
 544                                         }
 545                                 }
 546                         }
 547                 }
 548                 /* If all airports are unavailable, select nothing. */
 549                 this->SelectOtherAirport(-1);
 550         }
 551
 552         void OnDropdownSelect(int widget, int index) override
 553         {
 554                 assert(widget == WID_AP_CLASS_DROPDOWN);
 555                 _selected_airport_class = (AirportClassID)index;
 556                 this->vscroll->SetCount(AirportClass::Get(_selected_airport_class)->GetSpecCount());
 557                 this->SelectFirstAvailableAirport(false);
 558         }
 559
 560         void OnRealtimeTick(uint delta_ms) override
 561         {
 562                 CheckRedrawStationCoverage(this);
 563         }
 564 };
 565
 566 static const NWidgetPart _nested_build_airport_widgets[] = {
 567         NWidget(NWID_HORIZONTAL),
 568                 NWidget(WWT_CLOSEBOX, COLOUR_DARK_GREEN),
 569                 NWidget(WWT_CAPTION, COLOUR_DARK_GREEN), SetDataTip(STR_STATION_BUILD_AIRPORT_CAPTION, STR_TOOLTIP_WINDOW_TITLE_DRAG_THIS),
 570         EndContainer(),
 571         NWidget(WWT_PANEL, COLOUR_DARK_GREEN), SetFill(1, 0), SetPIP(2, 0, 2),
 572                 NWidget(WWT_LABEL, COLOUR_DARK_GREEN), SetDataTip(STR_STATION_BUILD_AIRPORT_CLASS_LABEL, STR_NULL), SetFill(1, 0),
 573                 NWidget(WWT_DROPDOWN, COLOUR_GREY, WID_AP_CLASS_DROPDOWN), SetFill(1, 0), SetDataTip(STR_BLACK_STRING, STR_STATION_BUILD_AIRPORT_TOOLTIP),
 574                 NWidget(WWT_EMPTY, COLOUR_DARK_GREEN, WID_AP_AIRPORT_SPRITE), SetFill(1, 0),
 575                 NWidget(NWID_HORIZONTAL),
 576                         NWidget(WWT_MATRIX, COLOUR_GREY, WID_AP_AIRPORT_LIST), SetFill(1, 0), SetMatrixDataTip(1, 5, STR_STATION_BUILD_AIRPORT_TOOLTIP), SetScrollbar(WID_AP_SCROLLBAR),
 577                         NWidget(NWID_VSCROLLBAR, COLOUR_GREY, WID_AP_SCROLLBAR),
 578                 EndContainer(),
 579                 NWidget(NWID_HORIZONTAL),
 580                         NWidget(WWT_PUSHARROWBTN, COLOUR_GREY, WID_AP_LAYOUT_DECREASE), SetMinimalSize(12, 0), SetDataTip(AWV_DECREASE, STR_NULL),
 581                         NWidget(WWT_LABEL, COLOUR_GREY, WID_AP_LAYOUT_NUM), SetResize(1, 0), SetFill(1, 0), SetDataTip(STR_BLACK_STRING, STR_NULL),
 582                         NWidget(WWT_PUSHARROWBTN, COLOUR_GREY, WID_AP_LAYOUT_INCREASE), SetMinimalSize(12, 0), SetDataTip(AWV_INCREASE, STR_NULL),
 583                 EndContainer(),
 584                 NWidget(WWT_EMPTY, COLOUR_DARK_GREEN, WID_AP_EXTRA_TEXT), SetFill(1, 0), SetMinimalSize(150, 0),
 585         EndContainer(),
 586         /* Bottom panel. */
 587         NWidget(WWT_PANEL, COLOUR_DARK_GREEN, WID_AP_BOTTOMPANEL), SetPIP(2, 2, 2),
 588                 NWidget(WWT_LABEL, COLOUR_DARK_GREEN), SetDataTip(STR_STATION_BUILD_COVERAGE_AREA_TITLE, STR_NULL), SetFill(1, 0),
 589                 NWidget(NWID_HORIZONTAL),
 590                         NWidget(NWID_SPACER), SetMinimalSize(14, 0), SetFill(1, 0),
 591                         NWidget(NWID_HORIZONTAL, NC_EQUALSIZE),
 592                                 NWidget(WWT_TEXTBTN, COLOUR_GREY, WID_AP_BTN_DONTHILIGHT), SetMinimalSize(60, 12), SetFill(1, 0),
 593                                                                                         SetDataTip(STR_STATION_BUILD_COVERAGE_OFF, STR_STATION_BUILD_COVERAGE_AREA_OFF_TOOLTIP),
 594                                 NWidget(WWT_TEXTBTN, COLOUR_GREY, WID_AP_BTN_DOHILIGHT), SetMinimalSize(60, 12), SetFill(1, 0),
 595                                                                                         SetDataTip(STR_STATION_BUILD_COVERAGE_ON, STR_STATION_BUILD_COVERAGE_AREA_ON_TOOLTIP),
 596                         EndContainer(),
 597                         NWidget(NWID_SPACER), SetMinimalSize(14, 0), SetFill(1, 0),
 598                 EndContainer(),
 599                 NWidget(NWID_SPACER), SetMinimalSize(0, 10), SetResize(0, 1), SetFill(1, 0),
 600         EndContainer(),
 601 };
 602
 603 static WindowDesc _build_airport_desc(
 604         WDP_AUTO, "build_station_air", 0, 0,
 605         WC_BUILD_STATION, WC_BUILD_TOOLBAR,
 606         WDF_CONSTRUCTION,
 607         _nested_build_airport_widgets, lengthof(_nested_build_airport_widgets)
 608 );
 609
 610 static void ShowBuildAirportPicker(Window *parent)
 611 {
 612         new BuildAirportWindow(&_build_airport_desc, parent);
 613 }
 614
 615 void InitializeAirportGui()
 616 {
 617         _selected_airport_class = APC_BEGIN;
 618         _selected_airport_index = -1;
 619 }