src/object_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 object_gui.cpp The GUI for objects. */
   9
  10 #include "stdafx.h"
  11 #include "command_func.h"
  12 #include "newgrf.h"
  13 #include "newgrf_object.h"
  14 #include "newgrf_text.h"
  15 #include "strings_func.h"
  16 #include "viewport_func.h"
  17 #include "tilehighlight_func.h"
  18 #include "window_gui.h"
  19 #include "window_func.h"
  20 #include "zoom_func.h"
  21
  22 #include "widgets/object_widget.h"
  23
  24 #include "table/strings.h"
  25
  26 #include "safeguards.h"
  27
  28 static ObjectClassID _selected_object_class; ///< the currently visible object class
  29 static int _selected_object_index;           ///< the index of the selected object in the current class or -1
  30 static uint8 _selected_object_view;          ///< the view of the selected object
  31
  32 /** The window used for building objects. */
  33 class BuildObjectWindow : public Window {
  34         static const int OBJECT_MARGIN = 4; ///< The margin (in pixels) around an object.
  35         int line_height;                    ///< The height of a single line.
  36         int info_height;                    ///< The height of the info box.
  37         Scrollbar *vscroll;                 ///< The scrollbar.
  38
  39         /** Scroll #WID_BO_CLASS_LIST so that the selected object class is visible. */
  40         void EnsureSelectedObjectClassIsVisible()
  41         {
  42                 uint pos = 0;
  43                 for (int i = 0; i < _selected_object_class; i++) {
  44                         if (ObjectClass::Get((ObjectClassID) i)->GetUISpecCount() == 0) continue;
  45                         pos++;
  46                 }
  47                 this->vscroll->ScrollTowards(pos);
  48         }
  49
  50         /**
  51          * Tests whether the previously selected object can be selected.
  52          * @return \c true if the selected object is available, \c false otherwise.
  53          */
  54         bool CanRestoreSelectedObject()
  55         {
  56                 if (_selected_object_index == -1) return false;
  57
  58                 ObjectClass *sel_objclass = ObjectClass::Get(_selected_object_class);
  59                 if ((int)sel_objclass->GetSpecCount() <= _selected_object_index) return false;
  60
  61                 return sel_objclass->GetSpec(_selected_object_index)->IsAvailable();
  62         }
  63
  64         /**
  65          * Calculate the number of columns of the #WID_BO_SELECT_MATRIX widget.
  66          * @return Number of columns in the matrix.
  67          */
  68         uint GetMatrixColumnCount()
  69         {
  70                 const NWidgetBase *matrix = this->GetWidget<NWidgetBase>(WID_BO_SELECT_MATRIX);
  71                 return 1 + (matrix->current_x - matrix->smallest_x) / matrix->resize_x;
  72         }
  73
  74 public:
  75         BuildObjectWindow(WindowDesc *desc, WindowNumber number) : Window(desc), info_height(1)
  76         {
  77                 this->CreateNestedTree();
  78                 this->vscroll = this->GetScrollbar(WID_BO_SCROLLBAR);
  79                 this->FinishInitNested(number);
  80
  81                 ResetObjectToPlace();
  82
  83                 this->vscroll->SetPosition(0);
  84                 this->vscroll->SetCount(ObjectClass::GetUIClassCount());
  85
  86                 NWidgetMatrix *matrix = this->GetWidget<NWidgetMatrix>(WID_BO_SELECT_MATRIX);
  87                 matrix->SetScrollbar(this->GetScrollbar(WID_BO_SELECT_SCROLL));
  88
  89                 this->SelectOtherClass(_selected_object_class);
  90                 if (this->CanRestoreSelectedObject()) {
  91                         this->SelectOtherObject(_selected_object_index);
  92                 } else {
  93                         this->SelectFirstAvailableObject(true);
  94                 }
  95                 assert(ObjectClass::Get(_selected_object_class)->GetUISpecCount() > 0); // object GUI should be disables elsewise
  96                 this->EnsureSelectedObjectClassIsVisible();
  97                 this->GetWidget<NWidgetMatrix>(WID_BO_OBJECT_MATRIX)->SetCount(4);
  98         }
  99
 100         void SetStringParameters(int widget) const override
 101         {
 102                 switch (widget) {
 103                         case WID_BO_OBJECT_NAME: {
 104                                 const ObjectSpec *spec = ObjectClass::Get(_selected_object_class)->GetSpec(_selected_object_index);
 105                                 SetDParam(0, spec != nullptr ? spec->name : STR_EMPTY);
 106                                 break;
 107                         }
 108
 109                         case WID_BO_OBJECT_SIZE: {
 110                                 const ObjectSpec *spec = ObjectClass::Get(_selected_object_class)->GetSpec(_selected_object_index);
 111                                 int size = spec == nullptr ? 0 : spec->size;
 112                                 SetDParam(0, GB(size, HasBit(_selected_object_view, 0) ? 4 : 0, 4));
 113                                 SetDParam(1, GB(size, HasBit(_selected_object_view, 0) ? 0 : 4, 4));
 114                                 break;
 115                         }
 116
 117                         default: break;
 118                 }
 119         }
 120
 121         void UpdateWidgetSize(int widget, Dimension *size, const Dimension &padding, Dimension *fill, Dimension *resize) override
 122         {
 123                 switch (widget) {
 124                         case WID_BO_CLASS_LIST: {
 125                                 for (uint i = 0; i < ObjectClass::GetClassCount(); i++) {
 126                                         ObjectClass *objclass = ObjectClass::Get((ObjectClassID)i);
 127                                         if (objclass->GetUISpecCount() == 0) continue;
 128                                         size->width = max(size->width, GetStringBoundingBox(objclass->name).width);
 129                                 }
 130                                 size->width += padding.width;
 131                                 this->line_height = FONT_HEIGHT_NORMAL + WD_MATRIX_TOP + WD_MATRIX_BOTTOM;
 132                                 resize->height = this->line_height;
 133                                 size->height = 5 * this->line_height;
 134                                 break;
 135                         }
 136
 137                         case WID_BO_OBJECT_NAME:
 138                         case WID_BO_OBJECT_SIZE:
 139                                 /* We do not want the window to resize when selecting objects; better clip texts */
 140                                 size->width = 0;
 141                                 break;
 142
 143                         case WID_BO_OBJECT_MATRIX: {
 144                                 /* Get the right amount of buttons based on the current spec. */
 145                                 const ObjectSpec *spec = ObjectClass::Get(_selected_object_class)->GetSpec(_selected_object_index);
 146                                 if (spec != nullptr) {
 147                                         if (spec->views >= 2) size->width  += resize->width;
 148                                         if (spec->views >= 4) size->height += resize->height;
 149                                 }
 150                                 resize->width = 0;
 151                                 resize->height = 0;
 152                                 break;
 153                         }
 154
 155                         case WID_BO_OBJECT_SPRITE: {
 156                                 bool two_wide = false;  // Whether there will be two widgets next to each other in the matrix or not.
 157                                 int height[2] = {0, 0}; // The height for the different views; in this case views 1/2 and 4.
 158
 159                                 /* Get the height and view information. */
 160                                 for (int i = 0; i < NUM_OBJECTS; i++) {
 161                                         const ObjectSpec *spec = ObjectSpec::Get(i);
 162                                         if (!spec->IsEverAvailable()) continue;
 163                                         two_wide |= spec->views >= 2;
 164                                         height[spec->views / 4] = max<int>(ObjectSpec::Get(i)->height, height[spec->views / 4]);
 165                                 }
 166
 167                                 /* Determine the pixel heights. */
 168                                 for (size_t i = 0; i < lengthof(height); i++) {
 169                                         height[i] *= ScaleGUITrad(TILE_HEIGHT);
 170                                         height[i] += ScaleGUITrad(TILE_PIXELS) + 2 * OBJECT_MARGIN;
 171                                 }
 172
 173                                 /* Now determine the size of the minimum widgets. When there are two columns, then
 174                                  * we want these columns to be slightly less wide. When there are two rows, then
 175                                  * determine the size of the widgets based on the maximum size for a single row
 176                                  * of widgets, or just the twice the widget height of the two row ones. */
 177                                 size->height = max(height[0], height[1] * 2 + 2);
 178                                 if (two_wide) {
 179                                         size->width  = (3 * ScaleGUITrad(TILE_PIXELS) + 2 * OBJECT_MARGIN) * 2 + 2;
 180                                 } else {
 181                                         size->width  = 4 * ScaleGUITrad(TILE_PIXELS) + 2 * OBJECT_MARGIN;
 182                                 }
 183
 184                                 /* Get the right size for the single widget based on the current spec. */
 185                                 const ObjectSpec *spec = ObjectClass::Get(_selected_object_class)->GetSpec(_selected_object_index);
 186                                 if (spec != nullptr) {
 187                                         if (spec->views >= 2) size->width  = size->width  / 2 - 1;
 188                                         if (spec->views >= 4) size->height = size->height / 2 - 1;
 189                                 }
 190                                 break;
 191                         }
 192
 193                         case WID_BO_INFO:
 194                                 size->height = this->info_height;
 195                                 break;
 196
 197                         case WID_BO_SELECT_MATRIX:
 198                                 fill->height = 1;
 199                                 resize->height = 1;
 200                                 break;
 201
 202                         case WID_BO_SELECT_IMAGE:
 203                                 size->width  = ScaleGUITrad(64) + 2;
 204                                 size->height = ScaleGUITrad(58) + 2;
 205                                 break;
 206
 207                         default: break;
 208                 }
 209         }
 210
 211         void DrawWidget(const Rect &r, int widget) const override
 212         {
 213                 switch (GB(widget, 0, 16)) {
 214                         case WID_BO_CLASS_LIST: {
 215                                 int y = r.top;
 216                                 uint pos = 0;
 217                                 for (uint i = 0; i < ObjectClass::GetClassCount(); i++) {
 218                                         ObjectClass *objclass = ObjectClass::Get((ObjectClassID)i);
 219                                         if (objclass->GetUISpecCount() == 0) continue;
 220                                         if (!this->vscroll->IsVisible(pos++)) continue;
 221                                         DrawString(r.left + WD_MATRIX_LEFT, r.right - WD_MATRIX_RIGHT, y + WD_MATRIX_TOP, objclass->name,
 222                                                         ((int)i == _selected_object_class) ? TC_WHITE : TC_BLACK);
 223                                         y += this->line_height;
 224                                 }
 225                                 break;
 226                         }
 227
 228                         case WID_BO_OBJECT_SPRITE: {
 229                                 const ObjectSpec *spec = ObjectClass::Get(_selected_object_class)->GetSpec(_selected_object_index);
 230                                 if (spec == nullptr) break;
 231
 232                                 /* Height of the selection matrix.
 233                                  * Depending on the number of views, the matrix has a 1x1, 1x2, 2x1 or 2x2 layout. To make the previews
 234                                  * look nice in all layouts, we use the 4x4 layout (smallest previews) as starting point. For the bigger
 235                                  * previews in the layouts with less views we add space homogeneously on all sides, so the 4x4 preview-rectangle
 236                                  * is centered in the 2x1, 1x2 resp. 1x1 buttons. */
 237                                 uint matrix_height = this->GetWidget<NWidgetMatrix>(WID_BO_OBJECT_MATRIX)->current_y;
 238
 239                                 DrawPixelInfo tmp_dpi;
 240                                 /* Set up a clipping area for the preview. */
 241                                 if (FillDrawPixelInfo(&tmp_dpi, r.left, r.top, r.right - r.left + 1, r.bottom - r.top + 1)) {
 242                                         DrawPixelInfo *old_dpi = _cur_dpi;
 243                                         _cur_dpi = &tmp_dpi;
 244                                         if (spec->grf_prop.grffile == nullptr) {
 245                                                 extern const DrawTileSprites _objects[];
 246                                                 const DrawTileSprites *dts = &_objects[spec->grf_prop.local_id];
 247                                                 DrawOrigTileSeqInGUI((r.right - r.left) / 2 - 1, (r.bottom - r.top + matrix_height / 2) / 2 - OBJECT_MARGIN - ScaleGUITrad(TILE_PIXELS), dts, PAL_NONE);
 248                                         } else {
 249                                                 DrawNewObjectTileInGUI((r.right - r.left) / 2 - 1, (r.bottom - r.top + matrix_height / 2) / 2 - OBJECT_MARGIN - ScaleGUITrad(TILE_PIXELS), spec, GB(widget, 16, 16));
 250                                         }
 251                                         _cur_dpi = old_dpi;
 252                                 }
 253                                 break;
 254                         }
 255
 256                         case WID_BO_SELECT_IMAGE: {
 257                                 ObjectClass *objclass = ObjectClass::Get(_selected_object_class);
 258                                 int obj_index = objclass->GetIndexFromUI(GB(widget, 16, 16));
 259                                 if (obj_index < 0) break;
 260                                 const ObjectSpec *spec = objclass->GetSpec(obj_index);
 261                                 if (spec == nullptr) break;
 262
 263                                 if (!spec->IsAvailable()) {
 264                                         GfxFillRect(r.left + 1, r.top + 1, r.right - 1, r.bottom - 1, PC_BLACK, FILLRECT_CHECKER);
 265                                 }
 266                                 DrawPixelInfo tmp_dpi;
 267                                 /* Set up a clipping area for the preview. */
 268                                 if (FillDrawPixelInfo(&tmp_dpi, r.left + 1, r.top, (r.right - 1) - (r.left + 1) + 1, r.bottom - r.top + 1)) {
 269                                         DrawPixelInfo *old_dpi = _cur_dpi;
 270                                         _cur_dpi = &tmp_dpi;
 271                                         if (spec->grf_prop.grffile == nullptr) {
 272                                                 extern const DrawTileSprites _objects[];
 273                                                 const DrawTileSprites *dts = &_objects[spec->grf_prop.local_id];
 274                                                 DrawOrigTileSeqInGUI((r.right - r.left) / 2 - 1, r.bottom - r.top - OBJECT_MARGIN - ScaleGUITrad(TILE_PIXELS), dts, PAL_NONE);
 275                                         } else {
 276                                                 DrawNewObjectTileInGUI((r.right - r.left) / 2 - 1, r.bottom - r.top - OBJECT_MARGIN - ScaleGUITrad(TILE_PIXELS), spec,
 277                                                                 min(_selected_object_view, spec->views - 1));
 278                                         }
 279                                         _cur_dpi = old_dpi;
 280                                 }
 281                                 break;
 282                         }
 283
 284                         case WID_BO_INFO: {
 285                                 const ObjectSpec *spec = ObjectClass::Get(_selected_object_class)->GetSpec(_selected_object_index);
 286                                 if (spec == nullptr) break;
 287
 288                                 /* Get the extra message for the GUI */
 289                                 if (HasBit(spec->callback_mask, CBM_OBJ_FUND_MORE_TEXT)) {
 290                                         uint16 callback_res = GetObjectCallback(CBID_OBJECT_FUND_MORE_TEXT, 0, 0, spec, nullptr, INVALID_TILE, _selected_object_view);
 291                                         if (callback_res != CALLBACK_FAILED && callback_res != 0x400) {
 292                                                 if (callback_res > 0x400) {
 293                                                         ErrorUnknownCallbackResult(spec->grf_prop.grffile->grfid, CBID_OBJECT_FUND_MORE_TEXT, callback_res);
 294                                                 } else {
 295                                                         StringID message = GetGRFStringID(spec->grf_prop.grffile->grfid, 0xD000 + callback_res);
 296                                                         if (message != STR_NULL && message != STR_UNDEFINED) {
 297                                                                 StartTextRefStackUsage(spec->grf_prop.grffile, 6);
 298                                                                 /* Use all the available space left from where we stand up to the
 299                                                                  * end of the window. We ALSO enlarge the window if needed, so we
 300                                                                  * can 'go' wild with the bottom of the window. */
 301                                                                 int y = DrawStringMultiLine(r.left, r.right, r.top, UINT16_MAX, message, TC_ORANGE) - r.top;
 302                                                                 StopTextRefStackUsage();
 303                                                                 if (y > this->info_height) {
 304                                                                         BuildObjectWindow *bow = const_cast<BuildObjectWindow *>(this);
 305                                                                         bow->info_height = y + 2;
 306                                                                         bow->ReInit();
 307                                                                 }
 308                                                         }
 309                                                 }
 310                                         }
 311                                 }
 312                         }
 313                 }
 314         }
 315
 316         /**
 317          * Select the specified object class.
 318          * @param object_class_index Object class index to select.
 319          */
 320         void SelectOtherClass(ObjectClassID object_class_index)
 321         {
 322                 _selected_object_class = object_class_index;
 323                 this->GetWidget<NWidgetMatrix>(WID_BO_SELECT_MATRIX)->SetCount(ObjectClass::Get(_selected_object_class)->GetUISpecCount());
 324         }
 325
 326         /**
 327          * Select the specified object in #_selected_object_class class.
 328          * @param object_index Object index to select, \c -1 means select nothing.
 329          */
 330         void SelectOtherObject(int object_index)
 331         {
 332                 _selected_object_index = object_index;
 333                 if (_selected_object_index != -1) {
 334                         const ObjectSpec *spec = ObjectClass::Get(_selected_object_class)->GetSpec(_selected_object_index);
 335                         _selected_object_view = min(_selected_object_view, spec->views - 1);
 336                         this->ReInit();
 337                 } else {
 338                         _selected_object_view = 0;
 339                 }
 340
 341                 if (_selected_object_index != -1) {
 342                         SetObjectToPlaceWnd(SPR_CURSOR_TRANSMITTER, PAL_NONE, HT_RECT, this);
 343                 }
 344
 345                 this->UpdateButtons(_selected_object_class, _selected_object_index, _selected_object_view);
 346         }
 347
 348         void UpdateSelectSize()
 349         {
 350                 if (_selected_object_index == -1) {
 351                         SetTileSelectSize(1, 1);
 352                 } else {
 353                         const ObjectSpec *spec = ObjectClass::Get(_selected_object_class)->GetSpec(_selected_object_index);
 354                         int w = GB(spec->size, HasBit(_selected_object_view, 0) ? 4 : 0, 4);
 355                         int h = GB(spec->size, HasBit(_selected_object_view, 0) ? 0 : 4, 4);
 356                         SetTileSelectSize(w, h);
 357                 }
 358         }
 359
 360         /**
 361          * Update buttons to show the selection to the user.
 362          * @param sel_class The class of the selected object.
 363          * @param sel_index Index of the object to select, or \c -1 .
 364          * @param sel_view View of the object to select.
 365          */
 366         void UpdateButtons(ObjectClassID sel_class, int sel_index, uint sel_view)
 367         {
 368                 int view_number, object_number;
 369                 if (sel_index == -1) {
 370                         view_number = -1; // If no object selected, also hide the selected view.
 371                         object_number = -1;
 372                 } else {
 373                         view_number = sel_view;
 374                         object_number = ObjectClass::Get(sel_class)->GetUIFromIndex(sel_index);
 375                 }
 376
 377                 this->GetWidget<NWidgetMatrix>(WID_BO_OBJECT_MATRIX)->SetClicked(view_number);
 378                 this->GetWidget<NWidgetMatrix>(WID_BO_SELECT_MATRIX)->SetClicked(object_number);
 379                 this->UpdateSelectSize();
 380                 this->SetDirty();
 381         }
 382
 383         void OnResize() override
 384         {
 385                 this->vscroll->SetCapacityFromWidget(this, WID_BO_CLASS_LIST);
 386         }
 387
 388         void OnClick(Point pt, int widget, int click_count) override
 389         {
 390                 switch (GB(widget, 0, 16)) {
 391                         case WID_BO_CLASS_LIST: {
 392                                 int num_clicked = this->vscroll->GetPosition() + (pt.y - this->nested_array[widget]->pos_y) / this->line_height;
 393                                 if (num_clicked >= (int)ObjectClass::GetUIClassCount()) break;
 394
 395                                 this->SelectOtherClass(ObjectClass::GetUIClass(num_clicked));
 396                                 this->SelectFirstAvailableObject(false);
 397                                 break;
 398                         }
 399
 400                         case WID_BO_SELECT_IMAGE: {
 401                                 ObjectClass *objclass = ObjectClass::Get(_selected_object_class);
 402                                 int num_clicked = objclass->GetIndexFromUI(GB(widget, 16, 16));
 403                                 if (num_clicked >= 0 && objclass->GetSpec(num_clicked)->IsAvailable()) this->SelectOtherObject(num_clicked);
 404                                 break;
 405                         }
 406
 407                         case WID_BO_OBJECT_SPRITE:
 408                                 if (_selected_object_index != -1) {
 409                                         _selected_object_view = GB(widget, 16, 16);
 410                                         this->SelectOtherObject(_selected_object_index); // Re-select the object for a different view.
 411                                 }
 412                                 break;
 413                 }
 414         }
 415
 416         void OnPlaceObject(Point pt, TileIndex tile) override
 417         {
 418                 DoCommandP(tile, ObjectClass::Get(_selected_object_class)->GetSpec(_selected_object_index)->Index(),
 419                                 _selected_object_view, CMD_BUILD_OBJECT | CMD_MSG(STR_ERROR_CAN_T_BUILD_OBJECT), CcTerraform);
 420         }
 421
 422         void OnPlaceObjectAbort() override
 423         {
 424                 this->UpdateButtons(_selected_object_class, -1, _selected_object_view);
 425         }
 426
 427         /**
 428          * Select the first available object.
 429          * @param change_class If true, change the class if no object in the current
 430          *   class is available.
 431          */
 432         void SelectFirstAvailableObject(bool change_class)
 433         {
 434                 /* First try to select an object in the selected class. */
 435                 ObjectClass *sel_objclass = ObjectClass::Get(_selected_object_class);
 436                 for (uint i = 0; i < sel_objclass->GetSpecCount(); i++) {
 437                         const ObjectSpec *spec = sel_objclass->GetSpec(i);
 438                         if (spec->IsAvailable()) {
 439                                 this->SelectOtherObject(i);
 440                                 return;
 441                         }
 442                 }
 443                 if (change_class) {
 444                         /* If that fails, select the first available object
 445                          * from a random class. */
 446                         for (ObjectClassID j = OBJECT_CLASS_BEGIN; j < OBJECT_CLASS_MAX; j++) {
 447                                 ObjectClass *objclass = ObjectClass::Get(j);
 448                                 for (uint i = 0; i < objclass->GetSpecCount(); i++) {
 449                                         const ObjectSpec *spec = objclass->GetSpec(i);
 450                                         if (spec->IsAvailable()) {
 451                                                 this->SelectOtherClass(j);
 452                                                 this->SelectOtherObject(i);
 453                                                 return;
 454                                         }
 455                                 }
 456                         }
 457                 }
 458                 /* If all objects are unavailable, select nothing... */
 459                 if (ObjectClass::Get(_selected_object_class)->GetUISpecCount() == 0) {
 460                         /* ... but make sure that the class is not empty. */
 461                         for (ObjectClassID j = OBJECT_CLASS_BEGIN; j < OBJECT_CLASS_MAX; j++) {
 462                                 if (ObjectClass::Get(j)->GetUISpecCount() > 0) {
 463                                         this->SelectOtherClass(j);
 464                                         break;
 465                                 }
 466                         }
 467                 }
 468                 this->SelectOtherObject(-1);
 469         }
 470 };
 471
 472 static const NWidgetPart _nested_build_object_widgets[] = {
 473         NWidget(NWID_HORIZONTAL),
 474                 NWidget(WWT_CLOSEBOX, COLOUR_DARK_GREEN),
 475                 NWidget(WWT_CAPTION, COLOUR_DARK_GREEN), SetDataTip(STR_OBJECT_BUILD_CAPTION, STR_TOOLTIP_WINDOW_TITLE_DRAG_THIS),
 476                 NWidget(WWT_DEFSIZEBOX, COLOUR_DARK_GREEN),
 477         EndContainer(),
 478         NWidget(WWT_PANEL, COLOUR_DARK_GREEN),
 479                 NWidget(NWID_HORIZONTAL), SetPadding(2, 0, 0, 0),
 480                         NWidget(NWID_VERTICAL),
 481                                 NWidget(NWID_HORIZONTAL), SetPadding(0, 5, 2, 5),
 482                                         NWidget(WWT_MATRIX, COLOUR_GREY, WID_BO_CLASS_LIST), SetFill(1, 0), SetMatrixDataTip(1, 0, STR_OBJECT_BUILD_CLASS_TOOLTIP), SetScrollbar(WID_BO_SCROLLBAR),
 483                                         NWidget(NWID_VSCROLLBAR, COLOUR_GREY, WID_BO_SCROLLBAR),
 484                                 EndContainer(),
 485                                 NWidget(NWID_HORIZONTAL), SetPadding(0, 5, 0, 5),
 486                                         NWidget(NWID_MATRIX, COLOUR_DARK_GREEN, WID_BO_OBJECT_MATRIX), SetPIP(0, 2, 0),
 487                                                 NWidget(WWT_PANEL, COLOUR_GREY, WID_BO_OBJECT_SPRITE), SetDataTip(0x0, STR_OBJECT_BUILD_PREVIEW_TOOLTIP), EndContainer(),
 488                                         EndContainer(),
 489                                 EndContainer(),
 490                                 NWidget(WWT_TEXT, COLOUR_DARK_GREEN, WID_BO_OBJECT_NAME), SetDataTip(STR_ORANGE_STRING, STR_NULL), SetPadding(2, 5, 2, 5),
 491                                 NWidget(WWT_TEXT, COLOUR_DARK_GREEN, WID_BO_OBJECT_SIZE), SetDataTip(STR_OBJECT_BUILD_SIZE, STR_NULL), SetPadding(2, 5, 2, 5),
 492                         EndContainer(),
 493                         NWidget(WWT_PANEL, COLOUR_DARK_GREEN), SetScrollbar(WID_BO_SELECT_SCROLL),
 494                                 NWidget(NWID_HORIZONTAL),
 495                                         NWidget(NWID_MATRIX, COLOUR_DARK_GREEN, WID_BO_SELECT_MATRIX), SetFill(0, 1), SetPIP(0, 2, 0),
 496                                                 NWidget(WWT_PANEL, COLOUR_DARK_GREEN, WID_BO_SELECT_IMAGE), SetMinimalSize(66, 60), SetDataTip(0x0, STR_OBJECT_BUILD_TOOLTIP),
 497                                                                 SetFill(0, 0), SetResize(0, 0), SetScrollbar(WID_BO_SELECT_SCROLL),
 498                                                 EndContainer(),
 499                                         EndContainer(),
 500                                         NWidget(NWID_VSCROLLBAR, COLOUR_DARK_GREEN, WID_BO_SELECT_SCROLL),
 501                                 EndContainer(),
 502                         EndContainer(),
 503                 EndContainer(),
 504                 NWidget(NWID_HORIZONTAL),
 505                         NWidget(WWT_EMPTY, INVALID_COLOUR, WID_BO_INFO), SetPadding(2, 5, 0, 5), SetFill(1, 0), SetResize(1, 0),
 506                         NWidget(NWID_VERTICAL),
 507                                 NWidget(WWT_PANEL, COLOUR_DARK_GREEN), SetFill(0, 1), EndContainer(),
 508                                 NWidget(WWT_RESIZEBOX, COLOUR_DARK_GREEN),
 509                         EndContainer(),
 510                 EndContainer(),
 511         EndContainer(),
 512 };
 513
 514 static WindowDesc _build_object_desc(
 515         WDP_AUTO, "build_object", 0, 0,
 516         WC_BUILD_OBJECT, WC_BUILD_TOOLBAR,
 517         WDF_CONSTRUCTION,
 518         _nested_build_object_widgets, lengthof(_nested_build_object_widgets)
 519 );
 520
 521 /** Show our object picker.  */
 522 void ShowBuildObjectPicker()
 523 {
 524         /* Don't show the place object button when there are no objects to place. */
 525         if (ObjectClass::GetUIClassCount() > 0) {
 526                 AllocateWindowDescFront<BuildObjectWindow>(&_build_object_desc, 0);
 527         }
 528 }
 529
 530 /** Reset all data of the object GUI. */
 531 void InitializeObjectGui()
 532 {
 533         _selected_object_class = (ObjectClassID)0;
 534 }