src/video/sdl2_v.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 sdl2_v.cpp Implementation of the SDL2 video driver. */
   9
  10 #include "../stdafx.h"
  11 #include "../openttd.h"
  12 #include "../gfx_func.h"
  13 #include "../rev.h"
  14 #include "../blitter/factory.hpp"
  15 #include "../thread.h"
  16 #include "../progress.h"
  17 #include "../core/random_func.hpp"
  18 #include "../core/math_func.hpp"
  19 #include "../core/mem_func.hpp"
  20 #include "../core/geometry_func.hpp"
  21 #include "../fileio_func.h"
  22 #include "../framerate_type.h"
  23 #include "../window_func.h"
  24 #include "sdl2_v.h"
  25 #include <SDL.h>
  26 #ifdef __EMSCRIPTEN__
  27 #       include <emscripten.h>
  28 #       include <emscripten/html5.h>
  29 #endif
  30
  31 #include "../safeguards.h"
  32
  33 void VideoDriver_SDL_Base::MakeDirty(int left, int top, int width, int height)
  34 {
  35         Rect r = {left, top, left + width, top + height};
  36         this->dirty_rect = BoundingRect(this->dirty_rect, r);
  37 }
  38
  39 void VideoDriver_SDL_Base::CheckPaletteAnim()
  40 {
  41         if (!CopyPalette(this->local_palette)) return;
  42         this->MakeDirty(0, 0, _screen.width, _screen.height);
  43 }
  44
  45 static const Dimension default_resolutions[] = {
  46         {  640,  480 },
  47         {  800,  600 },
  48         { 1024,  768 },
  49         { 1152,  864 },
  50         { 1280,  800 },
  51         { 1280,  960 },
  52         { 1280, 1024 },
  53         { 1400, 1050 },
  54         { 1600, 1200 },
  55         { 1680, 1050 },
  56         { 1920, 1200 }
  57 };
  58
  59 static void FindResolutions()
  60 {
  61         _resolutions.clear();
  62
  63         for (int i = 0; i < SDL_GetNumDisplayModes(0); i++) {
  64                 SDL_DisplayMode mode;
  65                 SDL_GetDisplayMode(0, i, &mode);
  66
  67                 if (mode.w < 640 || mode.h < 480) continue;
  68                 if (std::find(_resolutions.begin(), _resolutions.end(), Dimension(mode.w, mode.h)) != _resolutions.end()) continue;
  69                 _resolutions.emplace_back(mode.w, mode.h);
  70         }
  71
  72         /* We have found no resolutions, show the default list */
  73         if (_resolutions.empty()) {
  74                 _resolutions.assign(std::begin(default_resolutions), std::end(default_resolutions));
  75         }
  76
  77         SortResolutions();
  78 }
  79
  80 static void GetAvailableVideoMode(uint *w, uint *h)
  81 {
  82         /* All modes available? */
  83         if (!_fullscreen || _resolutions.empty()) return;
  84
  85         /* Is the wanted mode among the available modes? */
  86         if (std::find(_resolutions.begin(), _resolutions.end(), Dimension(*w, *h)) != _resolutions.end()) return;
  87
  88         /* Use the closest possible resolution */
  89         uint best = 0;
  90         uint delta = Delta(_resolutions[0].width, *w) * Delta(_resolutions[0].height, *h);
  91         for (uint i = 1; i != _resolutions.size(); ++i) {
  92                 uint newdelta = Delta(_resolutions[i].width, *w) * Delta(_resolutions[i].height, *h);
  93                 if (newdelta < delta) {
  94                         best = i;
  95                         delta = newdelta;
  96                 }
  97         }
  98         *w = _resolutions[best].width;
  99         *h = _resolutions[best].height;
 100 }
 101
 102 static uint FindStartupDisplay(uint startup_display)
 103 {
 104         int num_displays = SDL_GetNumVideoDisplays();
 105
 106         /* If the user indicated a valid monitor, use that. */
 107         if (IsInsideBS(startup_display, 0, num_displays)) return startup_display;
 108
 109         /* Mouse position decides which display to use. */
 110         int mx, my;
 111         SDL_GetGlobalMouseState(&mx, &my);
 112         for (int display = 0; display < num_displays; ++display) {
 113                 SDL_Rect r;
 114                 if (SDL_GetDisplayBounds(display, &r) == 0 && IsInsideBS(mx, r.x, r.w) && IsInsideBS(my, r.y, r.h)) {
 115                         Debug(driver, 1, "SDL2: Mouse is at ({}, {}), use display {} ({}, {}, {}, {})", mx, my, display, r.x, r.y, r.w, r.h);
 116                         return display;
 117                 }
 118         }
 119
 120         return 0;
 121 }
 122
 123 void VideoDriver_SDL_Base::ClientSizeChanged(int w, int h, bool force)
 124 {
 125         /* Allocate backing store of the new size. */
 126         if (this->AllocateBackingStore(w, h, force)) {
 127                 CopyPalette(this->local_palette, true);
 128
 129                 BlitterFactory::GetCurrentBlitter()->PostResize();
 130
 131                 GameSizeChanged();
 132         }
 133 }
 134
 135 bool VideoDriver_SDL_Base::CreateMainWindow(uint w, uint h, uint flags)
 136 {
 137         if (this->sdl_window != nullptr) return true;
 138
 139         flags |= SDL_WINDOW_SHOWN | SDL_WINDOW_RESIZABLE;
 140
 141         if (_fullscreen) {
 142                 flags |= SDL_WINDOW_FULLSCREEN;
 143         }
 144
 145         int x = SDL_WINDOWPOS_UNDEFINED, y = SDL_WINDOWPOS_UNDEFINED;
 146         SDL_Rect r;
 147         if (SDL_GetDisplayBounds(this->startup_display, &r) == 0) {
 148                 x = r.x + std::max(0, r.w - static_cast<int>(w)) / 2;
 149                 y = r.y + std::max(0, r.h - static_cast<int>(h)) / 4; // decent desktops have taskbars at the bottom
 150         }
 151
 152         char caption[50];
 153         seprintf(caption, lastof(caption), "OpenTTD %s", _openttd_revision);
 154         this->sdl_window = SDL_CreateWindow(
 155                 caption,
 156                 x, y,
 157                 w, h,
 158                 flags);
 159
 160         if (this->sdl_window == nullptr) {
 161                 Debug(driver, 0, "SDL2: Couldn't allocate a window to draw on: {}", SDL_GetError());
 162                 return false;
 163         }
 164
 165         std::string icon_path = FioFindFullPath(BASESET_DIR, "openttd.32.bmp");
 166         if (!icon_path.empty()) {
 167                 /* Give the application an icon */
 168                 SDL_Surface *icon = SDL_LoadBMP(icon_path.c_str());
 169                 if (icon != nullptr) {
 170                         /* Get the colourkey, which will be magenta */
 171                         uint32 rgbmap = SDL_MapRGB(icon->format, 255, 0, 255);
 172
 173                         SDL_SetColorKey(icon, SDL_TRUE, rgbmap);
 174                         SDL_SetWindowIcon(this->sdl_window, icon);
 175                         SDL_FreeSurface(icon);
 176                 }
 177         }
 178
 179         return true;
 180 }
 181
 182 bool VideoDriver_SDL_Base::CreateMainSurface(uint w, uint h, bool resize)
 183 {
 184         GetAvailableVideoMode(&w, &h);
 185         Debug(driver, 1, "SDL2: using mode {}x{}", w, h);
 186
 187         if (!this->CreateMainWindow(w, h)) return false;
 188         if (resize) SDL_SetWindowSize(this->sdl_window, w, h);
 189         this->ClientSizeChanged(w, h, true);
 190
 191         /* When in full screen, we will always have the mouse cursor
 192          * within the window, even though SDL does not give us the
 193          * appropriate event to know this. */
 194         if (_fullscreen) _cursor.in_window = true;
 195
 196         return true;
 197 }
 198
 199 bool VideoDriver_SDL_Base::ClaimMousePointer()
 200 {
 201         /* Emscripten never claims the pointer, so we do not need to change the cursor visibility. */
 202 #ifndef __EMSCRIPTEN__
 203         SDL_ShowCursor(0);
 204 #endif
 205         return true;
 206 }
 207
 208 /**
 209  * This is called to indicate that an edit box has gained focus, text input mode should be enabled.
 210  */
 211 void VideoDriver_SDL_Base::EditBoxGainedFocus()
 212 {
 213         if (!this->edit_box_focused) {
 214                 SDL_StartTextInput();
 215                 this->edit_box_focused = true;
 216         }
 217 }
 218
 219 /**
 220  * This is called to indicate that an edit box has lost focus, text input mode should be disabled.
 221  */
 222 void VideoDriver_SDL_Base::EditBoxLostFocus()
 223 {
 224         if (this->edit_box_focused) {
 225                 SDL_StopTextInput();
 226                 this->edit_box_focused = false;
 227         }
 228 }
 229
 230 std::vector<int> VideoDriver_SDL_Base::GetListOfMonitorRefreshRates()
 231 {
 232         std::vector<int> rates = {};
 233         for (int i = 0; i < SDL_GetNumVideoDisplays(); i++) {
 234                 SDL_DisplayMode mode = {};
 235                 if (SDL_GetDisplayMode(i, 0, &mode) != 0) continue;
 236                 if (mode.refresh_rate != 0) rates.push_back(mode.refresh_rate);
 237         }
 238         return rates;
 239 }
 240
 241
 242 struct SDLVkMapping {
 243         SDL_Keycode vk_from;
 244         byte vk_count;
 245         byte map_to;
 246         bool unprintable;
 247 };
 248
 249 #define AS(x, z) {x, 0, z, false}
 250 #define AM(x, y, z, w) {x, (byte)(y - x), z, false}
 251 #define AS_UP(x, z) {x, 0, z, true}
 252 #define AM_UP(x, y, z, w) {x, (byte)(y - x), z, true}
 253
 254 static const SDLVkMapping _vk_mapping[] = {
 255         /* Pageup stuff + up/down */
 256         AS_UP(SDLK_PAGEUP,   WKC_PAGEUP),
 257         AS_UP(SDLK_PAGEDOWN, WKC_PAGEDOWN),
 258         AS_UP(SDLK_UP,     WKC_UP),
 259         AS_UP(SDLK_DOWN,   WKC_DOWN),
 260         AS_UP(SDLK_LEFT,   WKC_LEFT),
 261         AS_UP(SDLK_RIGHT,  WKC_RIGHT),
 262
 263         AS_UP(SDLK_HOME,   WKC_HOME),
 264         AS_UP(SDLK_END,    WKC_END),
 265
 266         AS_UP(SDLK_INSERT, WKC_INSERT),
 267         AS_UP(SDLK_DELETE, WKC_DELETE),
 268
 269         /* Map letters & digits */
 270         AM(SDLK_a, SDLK_z, 'A', 'Z'),
 271         AM(SDLK_0, SDLK_9, '0', '9'),
 272
 273         AS_UP(SDLK_ESCAPE,    WKC_ESC),
 274         AS_UP(SDLK_PAUSE,     WKC_PAUSE),
 275         AS_UP(SDLK_BACKSPACE, WKC_BACKSPACE),
 276
 277         AS(SDLK_SPACE,     WKC_SPACE),
 278         AS(SDLK_RETURN,    WKC_RETURN),
 279         AS(SDLK_TAB,       WKC_TAB),
 280
 281         /* Function keys */
 282         AM_UP(SDLK_F1, SDLK_F12, WKC_F1, WKC_F12),
 283
 284         /* Numeric part. */
 285         AM(SDLK_KP_0, SDLK_KP_9, '0', '9'),
 286         AS(SDLK_KP_DIVIDE,   WKC_NUM_DIV),
 287         AS(SDLK_KP_MULTIPLY, WKC_NUM_MUL),
 288         AS(SDLK_KP_MINUS,    WKC_NUM_MINUS),
 289         AS(SDLK_KP_PLUS,     WKC_NUM_PLUS),
 290         AS(SDLK_KP_ENTER,    WKC_NUM_ENTER),
 291         AS(SDLK_KP_PERIOD,   WKC_NUM_DECIMAL),
 292
 293         /* Other non-letter keys */
 294         AS(SDLK_SLASH,        WKC_SLASH),
 295         AS(SDLK_SEMICOLON,    WKC_SEMICOLON),
 296         AS(SDLK_EQUALS,       WKC_EQUALS),
 297         AS(SDLK_LEFTBRACKET,  WKC_L_BRACKET),
 298         AS(SDLK_BACKSLASH,    WKC_BACKSLASH),
 299         AS(SDLK_RIGHTBRACKET, WKC_R_BRACKET),
 300
 301         AS(SDLK_QUOTE,   WKC_SINGLEQUOTE),
 302         AS(SDLK_COMMA,   WKC_COMMA),
 303         AS(SDLK_MINUS,   WKC_MINUS),
 304         AS(SDLK_PERIOD,  WKC_PERIOD)
 305 };
 306
 307 static uint ConvertSdlKeyIntoMy(SDL_Keysym *sym, WChar *character)
 308 {
 309         const SDLVkMapping *map;
 310         uint key = 0;
 311         bool unprintable = false;
 312
 313         for (map = _vk_mapping; map != endof(_vk_mapping); ++map) {
 314                 if ((uint)(sym->sym - map->vk_from) <= map->vk_count) {
 315                         key = sym->sym - map->vk_from + map->map_to;
 316                         unprintable = map->unprintable;
 317                         break;
 318                 }
 319         }
 320
 321         /* check scancode for BACKQUOTE key, because we want the key left of "1", not anything else (on non-US keyboards) */
 322         if (sym->scancode == SDL_SCANCODE_GRAVE) key = WKC_BACKQUOTE;
 323
 324         /* META are the command keys on mac */
 325         if (sym->mod & KMOD_GUI)   key |= WKC_META;
 326         if (sym->mod & KMOD_SHIFT) key |= WKC_SHIFT;
 327         if (sym->mod & KMOD_CTRL)  key |= WKC_CTRL;
 328         if (sym->mod & KMOD_ALT)   key |= WKC_ALT;
 329
 330         /* The mod keys have no character. Prevent '?' */
 331         if (sym->mod & KMOD_GUI ||
 332                 sym->mod & KMOD_CTRL ||
 333                 sym->mod & KMOD_ALT ||
 334                 unprintable) {
 335                 *character = WKC_NONE;
 336         } else {
 337                 *character = sym->sym;
 338         }
 339
 340         return key;
 341 }
 342
 343 /**
 344  * Like ConvertSdlKeyIntoMy(), but takes an SDL_Keycode as input
 345  * instead of an SDL_Keysym.
 346  */
 347 static uint ConvertSdlKeycodeIntoMy(SDL_Keycode kc)
 348 {
 349         const SDLVkMapping *map;
 350         uint key = 0;
 351
 352         for (map = _vk_mapping; map != endof(_vk_mapping); ++map) {
 353                 if ((uint)(kc - map->vk_from) <= map->vk_count) {
 354                         key = kc - map->vk_from + map->map_to;
 355                         break;
 356                 }
 357         }
 358
 359         /* check scancode for BACKQUOTE key, because we want the key left
 360          * of "1", not anything else (on non-US keyboards) */
 361         SDL_Scancode sc = SDL_GetScancodeFromKey(kc);
 362         if (sc == SDL_SCANCODE_GRAVE) key = WKC_BACKQUOTE;
 363
 364         return key;
 365 }
 366
 367 bool VideoDriver_SDL_Base::PollEvent()
 368 {
 369         SDL_Event ev;
 370
 371         if (!SDL_PollEvent(&ev)) return false;
 372
 373         switch (ev.type) {
 374                 case SDL_MOUSEMOTION:
 375                         if (_cursor.UpdateCursorPosition(ev.motion.x, ev.motion.y, true)) {
 376                                 SDL_WarpMouseInWindow(this->sdl_window, _cursor.pos.x, _cursor.pos.y);
 377                         }
 378                         HandleMouseEvents();
 379                         break;
 380
 381                 case SDL_MOUSEWHEEL:
 382                         if (ev.wheel.y > 0) {
 383                                 _cursor.wheel--;
 384                         } else if (ev.wheel.y < 0) {
 385                                 _cursor.wheel++;
 386                         }
 387                         break;
 388
 389                 case SDL_MOUSEBUTTONDOWN:
 390                         if (_rightclick_emulate && SDL_GetModState() & KMOD_CTRL) {
 391                                 ev.button.button = SDL_BUTTON_RIGHT;
 392                         }
 393
 394                         switch (ev.button.button) {
 395                                 case SDL_BUTTON_LEFT:
 396                                         _left_button_down = true;
 397                                         break;
 398
 399                                 case SDL_BUTTON_RIGHT:
 400                                         _right_button_down = true;
 401                                         _right_button_clicked = true;
 402                                         break;
 403
 404                                 default: break;
 405                         }
 406                         HandleMouseEvents();
 407                         break;
 408
 409                 case SDL_MOUSEBUTTONUP:
 410                         if (_rightclick_emulate) {
 411                                 _right_button_down = false;
 412                                 _left_button_down = false;
 413                                 _left_button_clicked = false;
 414                         } else if (ev.button.button == SDL_BUTTON_LEFT) {
 415                                 _left_button_down = false;
 416                                 _left_button_clicked = false;
 417                         } else if (ev.button.button == SDL_BUTTON_RIGHT) {
 418                                 _right_button_down = false;
 419                         }
 420                         HandleMouseEvents();
 421                         break;
 422
 423                 case SDL_QUIT:
 424                         HandleExitGameRequest();
 425                         break;
 426
 427                 case SDL_KEYDOWN: // Toggle full-screen on ALT + ENTER/F
 428                         if ((ev.key.keysym.mod & (KMOD_ALT | KMOD_GUI)) &&
 429                                         (ev.key.keysym.sym == SDLK_RETURN || ev.key.keysym.sym == SDLK_f)) {
 430                                 if (ev.key.repeat == 0) ToggleFullScreen(!_fullscreen);
 431                         } else {
 432                                 WChar character;
 433
 434                                 uint keycode = ConvertSdlKeyIntoMy(&ev.key.keysym, &character);
 435                                 // Only handle non-text keys here. Text is handled in
 436                                 // SDL_TEXTINPUT below.
 437                                 if (!this->edit_box_focused ||
 438                                         keycode == WKC_DELETE ||
 439                                         keycode == WKC_NUM_ENTER ||
 440                                         keycode == WKC_LEFT ||
 441                                         keycode == WKC_RIGHT ||
 442                                         keycode == WKC_UP ||
 443                                         keycode == WKC_DOWN ||
 444                                         keycode == WKC_HOME ||
 445                                         keycode == WKC_END ||
 446                                         keycode & WKC_META ||
 447                                         keycode & WKC_CTRL ||
 448                                         keycode & WKC_ALT ||
 449                                         (keycode >= WKC_F1 && keycode <= WKC_F12) ||
 450                                         !IsValidChar(character, CS_ALPHANUMERAL)) {
 451                                         HandleKeypress(keycode, character);
 452                                 }
 453                         }
 454                         break;
 455
 456                 case SDL_TEXTINPUT: {
 457                         if (!this->edit_box_focused) break;
 458                         SDL_Keycode kc = SDL_GetKeyFromName(ev.text.text);
 459                         uint keycode = ConvertSdlKeycodeIntoMy(kc);
 460
 461                         if (keycode == WKC_BACKQUOTE && FocusedWindowIsConsole()) {
 462                                 WChar character;
 463                                 Utf8Decode(&character, ev.text.text);
 464                                 HandleKeypress(keycode, character);
 465                         } else {
 466                                 HandleTextInput(ev.text.text);
 467                         }
 468                         break;
 469                 }
 470                 case SDL_WINDOWEVENT: {
 471                         if (ev.window.event == SDL_WINDOWEVENT_EXPOSED) {
 472                                 // Force a redraw of the entire screen.
 473                                 this->MakeDirty(0, 0, _screen.width, _screen.height);
 474                         } else if (ev.window.event == SDL_WINDOWEVENT_SIZE_CHANGED) {
 475                                 int w = std::max(ev.window.data1, 64);
 476                                 int h = std::max(ev.window.data2, 64);
 477                                 CreateMainSurface(w, h, w != ev.window.data1 || h != ev.window.data2);
 478                         } else if (ev.window.event == SDL_WINDOWEVENT_ENTER) {
 479                                 // mouse entered the window, enable cursor
 480                                 _cursor.in_window = true;
 481 #ifdef __EMSCRIPTEN__
 482                                 /* Ensure pointer lock will not occur. */
 483                                 SDL_SetRelativeMouseMode(SDL_FALSE);
 484 #endif
 485                         } else if (ev.window.event == SDL_WINDOWEVENT_LEAVE) {
 486                                 // mouse left the window, undraw cursor
 487                                 UndrawMouseCursor();
 488                                 _cursor.in_window = false;
 489                         }
 490                         break;
 491                 }
 492         }
 493
 494         return true;
 495 }
 496
 497 static const char *InitializeSDL()
 498 {
 499         /* Explicitly disable hardware acceleration. Enabling this causes
 500          * UpdateWindowSurface() to update the window's texture instead of
 501          * its surface. */
 502         SDL_SetHint(SDL_HINT_FRAMEBUFFER_ACCELERATION, "0");
 503 #ifndef __EMSCRIPTEN__
 504         SDL_SetHint(SDL_HINT_MOUSE_RELATIVE_MODE_WARP, "1");
 505 #endif
 506
 507         /* Check if the video-driver is already initialized. */
 508         if (SDL_WasInit(SDL_INIT_VIDEO) != 0) return nullptr;
 509
 510         if (SDL_InitSubSystem(SDL_INIT_VIDEO) < 0) return SDL_GetError();
 511         return nullptr;
 512 }
 513
 514 const char *VideoDriver_SDL_Base::Initialize()
 515 {
 516         this->UpdateAutoResolution();
 517
 518         const char *error = InitializeSDL();
 519         if (error != nullptr) return error;
 520
 521         FindResolutions();
 522         Debug(driver, 2, "Resolution for display: {}x{}", _cur_resolution.width, _cur_resolution.height);
 523
 524         return nullptr;
 525 }
 526
 527 const char *VideoDriver_SDL_Base::Start(const StringList &param)
 528 {
 529         if (BlitterFactory::GetCurrentBlitter()->GetScreenDepth() == 0) return "Only real blitters supported";
 530
 531         const char *error = this->Initialize();
 532         if (error != nullptr) return error;
 533
 534         this->startup_display = FindStartupDisplay(GetDriverParamInt(param, "display", -1));
 535
 536         if (!CreateMainSurface(_cur_resolution.width, _cur_resolution.height, false)) {
 537                 return SDL_GetError();
 538         }
 539
 540         const char *dname = SDL_GetCurrentVideoDriver();
 541         Debug(driver, 1, "SDL2: using driver '{}'", dname);
 542
 543         this->driver_info = this->GetName();
 544         this->driver_info += " (";
 545         this->driver_info += dname;
 546         this->driver_info += ")";
 547
 548         MarkWholeScreenDirty();
 549
 550         SDL_StopTextInput();
 551         this->edit_box_focused = false;
 552
 553 #ifdef __EMSCRIPTEN__
 554         this->is_game_threaded = false;
 555 #else
 556         this->is_game_threaded = !GetDriverParamBool(param, "no_threads") && !GetDriverParamBool(param, "no_thread");
 557 #endif
 558
 559         return nullptr;
 560 }
 561
 562 void VideoDriver_SDL_Base::Stop()
 563 {
 564         SDL_QuitSubSystem(SDL_INIT_VIDEO);
 565         if (SDL_WasInit(SDL_INIT_EVERYTHING) == 0) {
 566                 SDL_Quit(); // If there's nothing left, quit SDL
 567         }
 568 }
 569
 570 void VideoDriver_SDL_Base::InputLoop()
 571 {
 572         uint32 mod = SDL_GetModState();
 573         const Uint8 *keys = SDL_GetKeyboardState(nullptr);
 574
 575         bool old_ctrl_pressed = _ctrl_pressed;
 576
 577         _ctrl_pressed  = !!(mod & KMOD_CTRL);
 578         _shift_pressed = !!(mod & KMOD_SHIFT);
 579
 580 #if defined(_DEBUG)
 581         this->fast_forward_key_pressed = _shift_pressed;
 582 #else
 583         /* Speedup when pressing tab, except when using ALT+TAB
 584          * to switch to another application. */
 585         this->fast_forward_key_pressed = keys[SDL_SCANCODE_TAB] && (mod & KMOD_ALT) == 0;
 586 #endif /* defined(_DEBUG) */
 587
 588         /* Determine which directional keys are down. */
 589         _dirkeys =
 590                 (keys[SDL_SCANCODE_LEFT]  ? 1 : 0) |
 591                 (keys[SDL_SCANCODE_UP]    ? 2 : 0) |
 592                 (keys[SDL_SCANCODE_RIGHT] ? 4 : 0) |
 593                 (keys[SDL_SCANCODE_DOWN]  ? 8 : 0);
 594
 595         if (old_ctrl_pressed != _ctrl_pressed) HandleCtrlChanged();
 596 }
 597
 598 void VideoDriver_SDL_Base::LoopOnce()
 599 {
 600         if (_exit_game) {
 601 #ifdef __EMSCRIPTEN__
 602                 /* Emscripten is event-driven, and as such the main loop is inside
 603                  * the browser. So if _exit_game goes true, the main loop ends (the
 604                  * cancel call), but we still have to call the cleanup that is
 605                  * normally done at the end of the main loop for non-Emscripten.
 606                  * After that, Emscripten just halts, and the HTML shows a nice
 607                  * "bye, see you next time" message. */
 608                 emscripten_cancel_main_loop();
 609                 emscripten_exit_pointerlock();
 610                 /* In effect, the game ends here. As emscripten_set_main_loop() caused
 611                  * the stack to be unwound, the code after MainLoop() in
 612                  * openttd_main() is never executed. */
 613                 EM_ASM(if (window["openttd_syncfs"]) openttd_syncfs());
 614                 EM_ASM(if (window["openttd_exit"]) openttd_exit());
 615 #endif
 616                 return;
 617         }
 618
 619         this->Tick();
 620
 621 /* Emscripten is running an event-based mainloop; there is already some
 622  * downtime between each iteration, so no need to sleep. */
 623 #ifndef __EMSCRIPTEN__
 624         this->SleepTillNextTick();
 625 #endif
 626 }
 627
 628 void VideoDriver_SDL_Base::MainLoop()
 629 {
 630 #ifdef __EMSCRIPTEN__
 631         /* Run the main loop event-driven, based on RequestAnimationFrame. */
 632         emscripten_set_main_loop_arg(&this->EmscriptenLoop, this, 0, 1);
 633 #else
 634         this->StartGameThread();
 635
 636         while (!_exit_game) {
 637                 LoopOnce();
 638         }
 639
 640         this->StopGameThread();
 641 #endif
 642 }
 643
 644 bool VideoDriver_SDL_Base::ChangeResolution(int w, int h)
 645 {
 646         return CreateMainSurface(w, h, true);
 647 }
 648
 649 bool VideoDriver_SDL_Base::ToggleFullscreen(bool fullscreen)
 650 {
 651         int w, h;
 652
 653         /* Remember current window size */
 654         if (fullscreen) {
 655                 SDL_GetWindowSize(this->sdl_window, &w, &h);
 656
 657                 /* Find fullscreen window size */
 658                 SDL_DisplayMode dm;
 659                 if (SDL_GetCurrentDisplayMode(0, &dm) < 0) {
 660                         Debug(driver, 0, "SDL_GetCurrentDisplayMode() failed: {}", SDL_GetError());
 661                 } else {
 662                         SDL_SetWindowSize(this->sdl_window, dm.w, dm.h);
 663                 }
 664         }
 665
 666         Debug(driver, 1, "SDL2: Setting {}", fullscreen ? "fullscreen" : "windowed");
 667         int ret = SDL_SetWindowFullscreen(this->sdl_window, fullscreen ? SDL_WINDOW_FULLSCREEN : 0);
 668         if (ret == 0) {
 669                 /* Switching resolution succeeded, set fullscreen value of window. */
 670                 _fullscreen = fullscreen;
 671                 if (!fullscreen) SDL_SetWindowSize(this->sdl_window, w, h);
 672         } else {
 673                 Debug(driver, 0, "SDL_SetWindowFullscreen() failed: {}", SDL_GetError());
 674         }
 675
 676         InvalidateWindowClassesData(WC_GAME_OPTIONS, 3);
 677         return ret == 0;
 678 }
 679
 680 bool VideoDriver_SDL_Base::AfterBlitterChange()
 681 {
 682         assert(BlitterFactory::GetCurrentBlitter()->GetScreenDepth() != 0);
 683         int w, h;
 684         SDL_GetWindowSize(this->sdl_window, &w, &h);
 685         return CreateMainSurface(w, h, false);
 686 }
 687
 688 Dimension VideoDriver_SDL_Base::GetScreenSize() const
 689 {
 690         SDL_DisplayMode mode;
 691         if (SDL_GetCurrentDisplayMode(this->startup_display, &mode) != 0) return VideoDriver::GetScreenSize();
 692
 693         return { static_cast<uint>(mode.w), static_cast<uint>(mode.h) };
 694 }
 695
 696 bool VideoDriver_SDL_Base::LockVideoBuffer()
 697 {
 698         if (this->buffer_locked) return false;
 699         this->buffer_locked = true;
 700
 701         _screen.dst_ptr = this->GetVideoPointer();
 702         assert(_screen.dst_ptr != nullptr);
 703
 704         return true;
 705 }
 706
 707 void VideoDriver_SDL_Base::UnlockVideoBuffer()
 708 {
 709         if (_screen.dst_ptr != nullptr) {
 710                 /* Hand video buffer back to the drawing backend. */
 711                 this->ReleaseVideoPointer();
 712                 _screen.dst_ptr = nullptr;
 713         }
 714
 715         this->buffer_locked = false;
 716 }