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 sdl_v.cpp Implementation of the SDL video driver. */
9 
10 #ifdef WITH_SDL
11 
12 #include "../stdafx.h"
13 #include "../openttd.h"
14 #include "../gfx_func.h"
15 #include "../rev.h"
16 #include "../blitter/factory.hpp"
17 #include "../thread.h"
18 #include "../progress.h"
19 #include "../core/random_func.hpp"
20 #include "../core/math_func.hpp"
21 #include "../fileio_func.h"
22 #include "../framerate_type.h"
23 #include "../window_func.h"
24 #include "sdl_v.h"
25 #include <SDL.h>
26 
27 #include "../safeguards.h"
28 
29 static FVideoDriver_SDL iFVideoDriver_SDL;
30 
31 static SDL_Surface *_sdl_surface;
32 static SDL_Surface *_sdl_realscreen;
33 static bool _all_modes;
34 
35 static Palette _local_palette;
36 
37 #define MAX_DIRTY_RECTS 100
38 static SDL_Rect _dirty_rects[MAX_DIRTY_RECTS];
39 static int _num_dirty_rects;
40 static int _use_hwpalette;
41 static int _requested_hwpalette; /* Did we request a HWPALETTE for the current video mode? */
42 
MakeDirty(int left,int top,int width,int height)43 void VideoDriver_SDL::MakeDirty(int left, int top, int width, int height)
44 {
45 	if (_num_dirty_rects < MAX_DIRTY_RECTS) {
46 		_dirty_rects[_num_dirty_rects].x = left;
47 		_dirty_rects[_num_dirty_rects].y = top;
48 		_dirty_rects[_num_dirty_rects].w = width;
49 		_dirty_rects[_num_dirty_rects].h = height;
50 	}
51 	_num_dirty_rects++;
52 }
53 
UpdatePalette(bool init=false)54 static void UpdatePalette(bool init = false)
55 {
56 	SDL_Color pal[256];
57 
58 	for (int i = 0; i != _local_palette.count_dirty; i++) {
59 		pal[i].r = _local_palette.palette[_local_palette.first_dirty + i].r;
60 		pal[i].g = _local_palette.palette[_local_palette.first_dirty + i].g;
61 		pal[i].b = _local_palette.palette[_local_palette.first_dirty + i].b;
62 		pal[i].unused = 0;
63 	}
64 
65 	SDL_SetColors(_sdl_surface, pal, _local_palette.first_dirty, _local_palette.count_dirty);
66 
67 	if (_sdl_surface != _sdl_realscreen && init) {
68 		/* When using a shadow surface, also set our palette on the real screen. This lets SDL
69 		 * allocate as many colors (or approximations) as
70 		 * possible, instead of using only the default SDL
71 		 * palette. This allows us to get more colors exactly
72 		 * right and might allow using better approximations for
73 		 * other colors.
74 		 *
75 		 * Note that colors allocations are tried in-order, so
76 		 * this favors colors further up into the palette. Also
77 		 * note that if two colors from the same animation
78 		 * sequence are approximated using the same color, that
79 		 * animation will stop working.
80 		 *
81 		 * Since changing the system palette causes the colours
82 		 * to change right away, and allocations might
83 		 * drastically change, we can't use this for animation,
84 		 * since that could cause weird coloring between the
85 		 * palette change and the blitting below, so we only set
86 		 * the real palette during initialisation.
87 		 */
88 		SDL_SetColors(_sdl_realscreen, pal, _local_palette.first_dirty, _local_palette.count_dirty);
89 	}
90 
91 	if (_sdl_surface != _sdl_realscreen && !init) {
92 		/* We're not using real hardware palette, but are letting SDL
93 		 * approximate the palette during shadow -> screen copy. To
94 		 * change the palette, we need to recopy the entire screen.
95 		 *
96 		 * Note that this operation can slow down the rendering
97 		 * considerably, especially since changing the shadow
98 		 * palette will need the next blit to re-detect the
99 		 * best mapping of shadow palette colors to real palette
100 		 * colors from scratch.
101 		 */
102 		SDL_BlitSurface(_sdl_surface, nullptr, _sdl_realscreen, nullptr);
103 		SDL_UpdateRect(_sdl_realscreen, 0, 0, 0, 0);
104 	}
105 }
106 
InitPalette()107 static void InitPalette()
108 {
109 	CopyPalette(_local_palette, true);
110 	UpdatePalette(true);
111 }
112 
CheckPaletteAnim()113 void VideoDriver_SDL::CheckPaletteAnim()
114 {
115 	if (!CopyPalette(_local_palette)) return;
116 
117 	Blitter *blitter = BlitterFactory::GetCurrentBlitter();
118 
119 	switch (blitter->UsePaletteAnimation()) {
120 		case Blitter::PALETTE_ANIMATION_VIDEO_BACKEND:
121 			UpdatePalette();
122 			break;
123 
124 		case Blitter::PALETTE_ANIMATION_BLITTER:
125 			blitter->PaletteAnimate(_local_palette);
126 			break;
127 
128 		case Blitter::PALETTE_ANIMATION_NONE:
129 			break;
130 
131 		default:
132 			NOT_REACHED();
133 	}
134 }
135 
Paint()136 void VideoDriver_SDL::Paint()
137 {
138 	PerformanceMeasurer framerate(PFE_VIDEO);
139 
140 	int n = _num_dirty_rects;
141 	if (n == 0) return;
142 
143 	_num_dirty_rects = 0;
144 
145 	if (n > MAX_DIRTY_RECTS) {
146 		if (_sdl_surface != _sdl_realscreen) {
147 			SDL_BlitSurface(_sdl_surface, nullptr, _sdl_realscreen, nullptr);
148 		}
149 
150 		SDL_UpdateRect(_sdl_realscreen, 0, 0, 0, 0);
151 	} else {
152 		if (_sdl_surface != _sdl_realscreen) {
153 			for (int i = 0; i < n; i++) {
154 				SDL_BlitSurface(_sdl_surface, &_dirty_rects[i], _sdl_realscreen, &_dirty_rects[i]);
155 			}
156 		}
157 
158 		SDL_UpdateRects(_sdl_realscreen, n, _dirty_rects);
159 	}
160 }
161 
162 static const Dimension _default_resolutions[] = {
163 	{ 640,  480},
164 	{ 800,  600},
165 	{1024,  768},
166 	{1152,  864},
167 	{1280,  800},
168 	{1280,  960},
169 	{1280, 1024},
170 	{1400, 1050},
171 	{1600, 1200},
172 	{1680, 1050},
173 	{1920, 1200}
174 };
175 
GetVideoModes()176 static void GetVideoModes()
177 {
178 	SDL_Rect **modes = SDL_ListModes(nullptr, SDL_SWSURFACE | SDL_FULLSCREEN);
179 	if (modes == nullptr) usererror("sdl: no modes available");
180 
181 	_resolutions.clear();
182 
183 	_all_modes = (SDL_ListModes(nullptr, SDL_SWSURFACE | (_fullscreen ? SDL_FULLSCREEN : 0)) == (void*)-1);
184 	if (modes == (void*)-1) {
185 		for (uint i = 0; i < lengthof(_default_resolutions); i++) {
186 			if (SDL_VideoModeOK(_default_resolutions[i].width, _default_resolutions[i].height, 8, SDL_FULLSCREEN) != 0) {
187 				_resolutions.push_back(_default_resolutions[i]);
188 			}
189 		}
190 	} else {
191 		for (int i = 0; modes[i]; i++) {
192 			uint w = modes[i]->w;
193 			uint h = modes[i]->h;
194 			if (w < 640 || h < 480) continue; // reject too small resolutions
195 			if (std::find(_resolutions.begin(), _resolutions.end(), Dimension(w, h)) != _resolutions.end()) continue;
196 			_resolutions.emplace_back(w, h);
197 		}
198 		if (_resolutions.empty()) usererror("No usable screen resolutions found!\n");
199 		SortResolutions();
200 	}
201 }
202 
GetAvailableVideoMode(uint * w,uint * h)203 static void GetAvailableVideoMode(uint *w, uint *h)
204 {
205 	/* All modes available? */
206 	if (_all_modes || _resolutions.empty()) return;
207 
208 	/* Is the wanted mode among the available modes? */
209 	if (std::find(_resolutions.begin(), _resolutions.end(), Dimension(*w, *h)) != _resolutions.end()) return;
210 
211 	/* Use the closest possible resolution */
212 	uint best = 0;
213 	uint delta = Delta(_resolutions[0].width, *w) * Delta(_resolutions[0].height, *h);
214 	for (uint i = 1; i != _resolutions.size(); ++i) {
215 		uint newdelta = Delta(_resolutions[i].width, *w) * Delta(_resolutions[i].height, *h);
216 		if (newdelta < delta) {
217 			best = i;
218 			delta = newdelta;
219 		}
220 	}
221 	*w = _resolutions[best].width;
222 	*h = _resolutions[best].height;
223 }
224 
CreateMainSurface(uint w,uint h)225 bool VideoDriver_SDL::CreateMainSurface(uint w, uint h)
226 {
227 	SDL_Surface *newscreen, *icon;
228 	char caption[50];
229 	int bpp = BlitterFactory::GetCurrentBlitter()->GetScreenDepth();
230 	bool want_hwpalette;
231 
232 	GetAvailableVideoMode(&w, &h);
233 
234 	Debug(driver, 1, "SDL: using mode {}x{}x{}", w, h, bpp);
235 
236 	if (bpp == 0) usererror("Can't use a blitter that blits 0 bpp for normal visuals");
237 
238 	std::string icon_path = FioFindFullPath(BASESET_DIR, "openttd.32.bmp");
239 	if (!icon_path.empty()) {
240 		/* Give the application an icon */
241 		icon = SDL_LoadBMP(icon_path.c_str());
242 		if (icon != nullptr) {
243 			/* Get the colourkey, which will be magenta */
244 			uint32 rgbmap = SDL_MapRGB(icon->format, 255, 0, 255);
245 
246 			SDL_SetColorKey(icon, SDL_SRCCOLORKEY, rgbmap);
247 			SDL_WM_SetIcon(icon, nullptr);
248 			SDL_FreeSurface(icon);
249 		}
250 	}
251 
252 	if (_use_hwpalette == 2) {
253 		/* Default is to autodetect when to use SDL_HWPALETTE.
254 		 * In this case, SDL_HWPALETTE is only used for 8bpp
255 		 * blitters in fullscreen.
256 		 *
257 		 * When using an 8bpp blitter on a 8bpp system in
258 		 * windowed mode with SDL_HWPALETTE, OpenTTD will claim
259 		 * the system palette, making all other applications
260 		 * get the wrong colours. In this case, we're better of
261 		 * trying to approximate the colors we need using system
262 		 * colors, using a shadow surface (see below).
263 		 *
264 		 * On a 32bpp system, SDL_HWPALETTE is ignored, so it
265 		 * doesn't matter what we do.
266 		 *
267 		 * When using a 32bpp blitter on a 8bpp system, setting
268 		 * SDL_HWPALETTE messes up rendering (at least on X11),
269 		 * so we don't do that. In this case, SDL takes care of
270 		 * color approximation using its own shadow surface
271 		 * (which we can't force in 8bpp on 8bpp mode,
272 		 * unfortunately).
273 		 */
274 		want_hwpalette = bpp == 8 && _fullscreen && _support8bpp == S8BPP_HARDWARE;
275 	} else {
276 		/* User specified a value manually */
277 		want_hwpalette = _use_hwpalette;
278 	}
279 
280 	if (want_hwpalette) Debug(driver, 1, "SDL: requesting hardware palette");
281 
282 	/* Free any previously allocated shadow surface */
283 	if (_sdl_surface != nullptr && _sdl_surface != _sdl_realscreen) SDL_FreeSurface(_sdl_surface);
284 
285 	if (_sdl_realscreen != nullptr) {
286 		if (_requested_hwpalette != want_hwpalette) {
287 			/* SDL (at least the X11 driver), reuses the
288 			 * same window and palette settings when the bpp
289 			 * (and a few flags) are the same. Since we need
290 			 * to hwpalette value to change (in particular
291 			 * when switching between fullscreen and
292 			 * windowed), we restart the entire video
293 			 * subsystem to force creating a new window.
294 			 */
295 			Debug(driver, 0, "SDL: Restarting SDL video subsystem, to force hwpalette change");
296 			SDL_QuitSubSystem(SDL_INIT_VIDEO);
297 			SDL_InitSubSystem(SDL_INIT_VIDEO);
298 			ClaimMousePointer();
299 			SetupKeyboard();
300 		}
301 	}
302 	/* Remember if we wanted a hwpalette. We can't reliably query
303 	 * SDL for the SDL_HWPALETTE flag, since it might get set even
304 	 * though we didn't ask for it (when SDL creates a shadow
305 	 * surface, for example). */
306 	_requested_hwpalette = want_hwpalette;
307 
308 	/* DO NOT CHANGE TO HWSURFACE, IT DOES NOT WORK */
309 	newscreen = SDL_SetVideoMode(w, h, bpp, SDL_SWSURFACE | (want_hwpalette ? SDL_HWPALETTE : 0) | (_fullscreen ? SDL_FULLSCREEN : SDL_RESIZABLE));
310 	if (newscreen == nullptr) {
311 		Debug(driver, 0, "SDL: Couldn't allocate a window to draw on");
312 		return false;
313 	}
314 	_sdl_realscreen = newscreen;
315 
316 	if (bpp == 8 && (_sdl_realscreen->flags & SDL_HWPALETTE) != SDL_HWPALETTE) {
317 		/* Using an 8bpp blitter, if we didn't get a hardware
318 		 * palette (most likely because we didn't request one,
319 		 * see above), we'll have to set up a shadow surface to
320 		 * render on.
321 		 *
322 		 * Our palette will be applied to this shadow surface,
323 		 * while the real screen surface will use the shared
324 		 * system palette (which will partly contain our colors,
325 		 * but most likely will not have enough free color cells
326 		 * for all of our colors). SDL can use these two
327 		 * palettes at blit time to approximate colors used in
328 		 * the shadow surface using system colors automatically.
329 		 *
330 		 * Note that when using an 8bpp blitter on a 32bpp
331 		 * system, SDL will create an internal shadow surface.
332 		 * This shadow surface will have SDL_HWPALLETE set, so
333 		 * we won't create a second shadow surface in this case.
334 		 */
335 		Debug(driver, 1, "SDL: using shadow surface");
336 		newscreen = SDL_CreateRGBSurface(SDL_SWSURFACE, w, h, bpp, 0, 0, 0, 0);
337 		if (newscreen == nullptr) {
338 			Debug(driver, 0, "SDL: Couldn't allocate a shadow surface to draw on");
339 			return false;
340 		}
341 	}
342 
343 	/* Delay drawing for this cycle; the next cycle will redraw the whole screen */
344 	_num_dirty_rects = 0;
345 
346 	_screen.width = newscreen->w;
347 	_screen.height = newscreen->h;
348 	_screen.pitch = newscreen->pitch / (bpp / 8);
349 	_screen.dst_ptr = newscreen->pixels;
350 	_sdl_surface = newscreen;
351 
352 	/* When in full screen, we will always have the mouse cursor
353 	 * within the window, even though SDL does not give us the
354 	 * appropriate event to know this. */
355 	if (_fullscreen) _cursor.in_window = true;
356 
357 	Blitter *blitter = BlitterFactory::GetCurrentBlitter();
358 	blitter->PostResize();
359 
360 	InitPalette();
361 
362 	seprintf(caption, lastof(caption), "OpenTTD %s", _openttd_revision);
363 	SDL_WM_SetCaption(caption, caption);
364 
365 	GameSizeChanged();
366 
367 	return true;
368 }
369 
ClaimMousePointer()370 bool VideoDriver_SDL::ClaimMousePointer()
371 {
372 	SDL_ShowCursor(0);
373 	return true;
374 }
375 
376 struct SDLVkMapping {
377 	uint16 vk_from;
378 	byte vk_count;
379 	byte map_to;
380 };
381 
382 #define AS(x, z) {x, 0, z}
383 #define AM(x, y, z, w) {x, (byte)(y - x), z}
384 
385 static const SDLVkMapping _vk_mapping[] = {
386 	/* Pageup stuff + up/down */
387 	AM(SDLK_PAGEUP, SDLK_PAGEDOWN, WKC_PAGEUP, WKC_PAGEDOWN),
388 	AS(SDLK_UP,     WKC_UP),
389 	AS(SDLK_DOWN,   WKC_DOWN),
390 	AS(SDLK_LEFT,   WKC_LEFT),
391 	AS(SDLK_RIGHT,  WKC_RIGHT),
392 
393 	AS(SDLK_HOME,   WKC_HOME),
394 	AS(SDLK_END,    WKC_END),
395 
396 	AS(SDLK_INSERT, WKC_INSERT),
397 	AS(SDLK_DELETE, WKC_DELETE),
398 
399 	/* Map letters & digits */
400 	AM(SDLK_a, SDLK_z, 'A', 'Z'),
401 	AM(SDLK_0, SDLK_9, '0', '9'),
402 
403 	AS(SDLK_ESCAPE,    WKC_ESC),
404 	AS(SDLK_PAUSE,     WKC_PAUSE),
405 	AS(SDLK_BACKSPACE, WKC_BACKSPACE),
406 
407 	AS(SDLK_SPACE,     WKC_SPACE),
408 	AS(SDLK_RETURN,    WKC_RETURN),
409 	AS(SDLK_TAB,       WKC_TAB),
410 
411 	/* Function keys */
412 	AM(SDLK_F1, SDLK_F12, WKC_F1, WKC_F12),
413 
414 	/* Numeric part. */
415 	AM(SDLK_KP0, SDLK_KP9, '0', '9'),
416 	AS(SDLK_KP_DIVIDE,   WKC_NUM_DIV),
417 	AS(SDLK_KP_MULTIPLY, WKC_NUM_MUL),
418 	AS(SDLK_KP_MINUS,    WKC_NUM_MINUS),
419 	AS(SDLK_KP_PLUS,     WKC_NUM_PLUS),
420 	AS(SDLK_KP_ENTER,    WKC_NUM_ENTER),
421 	AS(SDLK_KP_PERIOD,   WKC_NUM_DECIMAL),
422 
423 	/* Other non-letter keys */
424 	AS(SDLK_SLASH,        WKC_SLASH),
425 	AS(SDLK_SEMICOLON,    WKC_SEMICOLON),
426 	AS(SDLK_EQUALS,       WKC_EQUALS),
427 	AS(SDLK_LEFTBRACKET,  WKC_L_BRACKET),
428 	AS(SDLK_BACKSLASH,    WKC_BACKSLASH),
429 	AS(SDLK_RIGHTBRACKET, WKC_R_BRACKET),
430 
431 	AS(SDLK_QUOTE,   WKC_SINGLEQUOTE),
432 	AS(SDLK_COMMA,   WKC_COMMA),
433 	AS(SDLK_MINUS,   WKC_MINUS),
434 	AS(SDLK_PERIOD,  WKC_PERIOD)
435 };
436 
ConvertSdlKeyIntoMy(SDL_keysym * sym,WChar * character)437 static uint ConvertSdlKeyIntoMy(SDL_keysym *sym, WChar *character)
438 {
439 	const SDLVkMapping *map;
440 	uint key = 0;
441 
442 	for (map = _vk_mapping; map != endof(_vk_mapping); ++map) {
443 		if ((uint)(sym->sym - map->vk_from) <= map->vk_count) {
444 			key = sym->sym - map->vk_from + map->map_to;
445 			break;
446 		}
447 	}
448 
449 	/* check scancode for BACKQUOTE key, because we want the key left of "1", not anything else (on non-US keyboards) */
450 #if defined(_WIN32) || defined(__OS2__)
451 	if (sym->scancode == 41) key = WKC_BACKQUOTE;
452 #elif defined(__APPLE__)
453 	if (sym->scancode == 10) key = WKC_BACKQUOTE;
454 #elif defined(__SVR4) && defined(__sun)
455 	if (sym->scancode == 60) key = WKC_BACKQUOTE;
456 	if (sym->scancode == 49) key = WKC_BACKSPACE;
457 #elif defined(__sgi__)
458 	if (sym->scancode == 22) key = WKC_BACKQUOTE;
459 #else
460 	if (sym->scancode == 49) key = WKC_BACKQUOTE;
461 #endif
462 
463 	/* META are the command keys on mac */
464 	if (sym->mod & KMOD_META)  key |= WKC_META;
465 	if (sym->mod & KMOD_SHIFT) key |= WKC_SHIFT;
466 	if (sym->mod & KMOD_CTRL)  key |= WKC_CTRL;
467 	if (sym->mod & KMOD_ALT)   key |= WKC_ALT;
468 
469 	*character = sym->unicode;
470 	return key;
471 }
472 
PollEvent()473 bool VideoDriver_SDL::PollEvent()
474 {
475 	SDL_Event ev;
476 
477 	if (!SDL_PollEvent(&ev)) return false;
478 
479 	switch (ev.type) {
480 		case SDL_MOUSEMOTION:
481 			if (_cursor.UpdateCursorPosition(ev.motion.x, ev.motion.y, true)) {
482 				SDL_WarpMouse(_cursor.pos.x, _cursor.pos.y);
483 			}
484 			HandleMouseEvents();
485 			break;
486 
487 		case SDL_MOUSEBUTTONDOWN:
488 			if (_rightclick_emulate && SDL_GetModState() & KMOD_CTRL) {
489 				ev.button.button = SDL_BUTTON_RIGHT;
490 			}
491 
492 			switch (ev.button.button) {
493 				case SDL_BUTTON_LEFT:
494 					_left_button_down = true;
495 					break;
496 
497 				case SDL_BUTTON_RIGHT:
498 					_right_button_down = true;
499 					_right_button_clicked = true;
500 					break;
501 
502 				case SDL_BUTTON_WHEELUP:   _cursor.wheel--; break;
503 				case SDL_BUTTON_WHEELDOWN: _cursor.wheel++; break;
504 
505 				default: break;
506 			}
507 			HandleMouseEvents();
508 			break;
509 
510 		case SDL_MOUSEBUTTONUP:
511 			if (_rightclick_emulate) {
512 				_right_button_down = false;
513 				_left_button_down = false;
514 				_left_button_clicked = false;
515 			} else if (ev.button.button == SDL_BUTTON_LEFT) {
516 				_left_button_down = false;
517 				_left_button_clicked = false;
518 			} else if (ev.button.button == SDL_BUTTON_RIGHT) {
519 				_right_button_down = false;
520 			}
521 			HandleMouseEvents();
522 			break;
523 
524 		case SDL_ACTIVEEVENT:
525 			if (!(ev.active.state & SDL_APPMOUSEFOCUS)) break;
526 
527 			if (ev.active.gain) { // mouse entered the window, enable cursor
528 				_cursor.in_window = true;
529 			} else {
530 				UndrawMouseCursor(); // mouse left the window, undraw cursor
531 				_cursor.in_window = false;
532 			}
533 			break;
534 
535 		case SDL_QUIT:
536 			HandleExitGameRequest();
537 			break;
538 
539 		case SDL_KEYDOWN: // Toggle full-screen on ALT + ENTER/F
540 			if ((ev.key.keysym.mod & (KMOD_ALT | KMOD_META)) &&
541 					(ev.key.keysym.sym == SDLK_RETURN || ev.key.keysym.sym == SDLK_f)) {
542 				ToggleFullScreen(!_fullscreen);
543 			} else {
544 				WChar character;
545 				uint keycode = ConvertSdlKeyIntoMy(&ev.key.keysym, &character);
546 				HandleKeypress(keycode, character);
547 			}
548 			break;
549 
550 		case SDL_VIDEORESIZE: {
551 			int w = std::max(ev.resize.w, 64);
552 			int h = std::max(ev.resize.h, 64);
553 			CreateMainSurface(w, h);
554 			break;
555 		}
556 		case SDL_VIDEOEXPOSE: {
557 			/* Force a redraw of the entire screen. Note
558 			 * that SDL 1.2 seems to do this automatically
559 			 * in most cases, but 1.3 / 2.0 does not. */
560 		        _num_dirty_rects = MAX_DIRTY_RECTS + 1;
561 			break;
562 		}
563 	}
564 
565 	return true;
566 }
567 
Start(const StringList & param)568 const char *VideoDriver_SDL::Start(const StringList &param)
569 {
570 	char buf[30];
571 	_use_hwpalette = GetDriverParamInt(param, "hw_palette", 2);
572 
573 	/* Just on the offchance the audio subsystem started before the video system,
574 	 * check whether any part of SDL has been initialised before getting here.
575 	 * Slightly duplicated with sound/sdl_s.cpp */
576 	int ret_code = 0;
577 	if (SDL_WasInit(SDL_INIT_EVERYTHING) == 0) {
578 		ret_code = SDL_Init(SDL_INIT_VIDEO | SDL_INIT_NOPARACHUTE);
579 	} else if (SDL_WasInit(SDL_INIT_VIDEO) == 0) {
580 		ret_code = SDL_InitSubSystem(SDL_INIT_VIDEO);
581 	}
582 	if (ret_code < 0) return SDL_GetError();
583 
584 	this->UpdateAutoResolution();
585 
586 	GetVideoModes();
587 	if (!CreateMainSurface(_cur_resolution.width, _cur_resolution.height)) {
588 		return SDL_GetError();
589 	}
590 
591 	SDL_VideoDriverName(buf, sizeof buf);
592 	Debug(driver, 1, "SDL: using driver '{}'", buf);
593 
594 	MarkWholeScreenDirty();
595 	SetupKeyboard();
596 
597 	this->is_game_threaded = !GetDriverParamBool(param, "no_threads") && !GetDriverParamBool(param, "no_thread");
598 
599 	return nullptr;
600 }
601 
SetupKeyboard()602 void VideoDriver_SDL::SetupKeyboard()
603 {
604 	SDL_EnableKeyRepeat(SDL_DEFAULT_REPEAT_DELAY, SDL_DEFAULT_REPEAT_INTERVAL);
605 	SDL_EnableUNICODE(1);
606 }
607 
Stop()608 void VideoDriver_SDL::Stop()
609 {
610 	SDL_QuitSubSystem(SDL_INIT_VIDEO);
611 	if (SDL_WasInit(SDL_INIT_EVERYTHING) == 0) {
612 		SDL_Quit(); // If there's nothing left, quit SDL
613 	}
614 }
615 
InputLoop()616 void VideoDriver_SDL::InputLoop()
617 {
618 	uint32 mod = SDL_GetModState();
619 	int numkeys;
620 	Uint8 *keys = SDL_GetKeyState(&numkeys);
621 
622 	bool old_ctrl_pressed = _ctrl_pressed;
623 
624 	_ctrl_pressed  = !!(mod & KMOD_CTRL);
625 	_shift_pressed = !!(mod & KMOD_SHIFT);
626 
627 #if defined(_DEBUG)
628 	this->fast_forward_key_pressed = _shift_pressed;
629 #else
630 	/* Speedup when pressing tab, except when using ALT+TAB
631 	 * to switch to another application. */
632 	this->fast_forward_key_pressed = keys[SDLK_TAB] && (mod & KMOD_ALT) == 0;
633 #endif /* defined(_DEBUG) */
634 
635 	/* Determine which directional keys are down. */
636 	_dirkeys =
637 		(keys[SDLK_LEFT]  ? 1 : 0) |
638 		(keys[SDLK_UP]    ? 2 : 0) |
639 		(keys[SDLK_RIGHT] ? 4 : 0) |
640 		(keys[SDLK_DOWN]  ? 8 : 0);
641 
642 	if (old_ctrl_pressed != _ctrl_pressed) HandleCtrlChanged();
643 }
644 
MainLoop()645 void VideoDriver_SDL::MainLoop()
646 {
647 	this->StartGameThread();
648 
649 	for (;;) {
650 		if (_exit_game) break;
651 
652 		this->Tick();
653 		this->SleepTillNextTick();
654 	}
655 
656 	this->StopGameThread();
657 }
658 
ChangeResolution(int w,int h)659 bool VideoDriver_SDL::ChangeResolution(int w, int h)
660 {
661 	return CreateMainSurface(w, h);
662 }
663 
ToggleFullscreen(bool fullscreen)664 bool VideoDriver_SDL::ToggleFullscreen(bool fullscreen)
665 {
666 	_fullscreen = fullscreen;
667 	GetVideoModes(); // get the list of available video modes
668 	bool ret = !_resolutions.empty() && CreateMainSurface(_cur_resolution.width, _cur_resolution.height);
669 
670 	if (!ret) {
671 		/* switching resolution failed, put back full_screen to original status */
672 		_fullscreen ^= true;
673 	}
674 
675 	InvalidateWindowClassesData(WC_GAME_OPTIONS, 3);
676 	return ret;
677 }
678 
AfterBlitterChange()679 bool VideoDriver_SDL::AfterBlitterChange()
680 {
681 	return CreateMainSurface(_screen.width, _screen.height);
682 }
683 
684 #endif /* WITH_SDL */
685