summaryrefslogtreecommitdiff
path: root/src/video/win32_v.cpp
blob: 1dc1db8cef0dd7dd5918dd6e9f5c9fb47c4d6430 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
/*
 * This file is part of OpenTTD.
 * 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.
 * 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.
 * 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/>.
 */

/** @file win32_v.cpp Implementation of the Windows (GDI) video driver. */

#include "../stdafx.h"
#include "../openttd.h"
#include "../gfx_func.h"
#include "../os/windows/win32.h"
#include "../rev.h"
#include "../blitter/factory.hpp"
#include "../core/geometry_func.hpp"
#include "../core/math_func.hpp"
#include "../core/random_func.hpp"
#include "../texteff.hpp"
#include "../thread.h"
#include "../progress.h"
#include "../window_gui.h"
#include "../window_func.h"
#include "../framerate_type.h"
#include "win32_v.h"
#include <windows.h>
#include <imm.h>

#include "../safeguards.h"

/* Missing define in MinGW headers. */
#ifndef MAPVK_VK_TO_CHAR
#define MAPVK_VK_TO_CHAR    (2)
#endif

#ifndef PM_QS_INPUT
#define PM_QS_INPUT 0x20000
#endif

bool _window_maximize;
static Dimension _bck_resolution;
DWORD _imm_props;

/** Local copy of the palette for use in the drawing thread. */
static Palette _local_palette;

bool VideoDriver_Win32Base::ClaimMousePointer()
{
	MyShowCursor(false, true);
	return true;
}

struct Win32VkMapping {
	byte vk_from;
	byte vk_count;
	byte map_to;
};

#define AS(x, z) {x, 0, z}
#define AM(x, y, z, w) {x, y - x, z}

static const Win32VkMapping _vk_mapping[] = {
	/* Pageup stuff + up/down */
	AM(VK_PRIOR, VK_DOWN, WKC_PAGEUP, WKC_DOWN),
	/* Map letters & digits */
	AM('A', 'Z', 'A', 'Z'),
	AM('0', '9', '0', '9'),

	AS(VK_ESCAPE,   WKC_ESC),
	AS(VK_PAUSE,    WKC_PAUSE),
	AS(VK_BACK,     WKC_BACKSPACE),
	AM(VK_INSERT,   VK_DELETE, WKC_INSERT, WKC_DELETE),

	AS(VK_SPACE,    WKC_SPACE),
	AS(VK_RETURN,   WKC_RETURN),
	AS(VK_TAB,      WKC_TAB),

	/* Function keys */
	AM(VK_F1, VK_F12, WKC_F1, WKC_F12),

	/* Numeric part */
	AM(VK_NUMPAD0, VK_NUMPAD9, '0', '9'),
	AS(VK_DIVIDE,   WKC_NUM_DIV),
	AS(VK_MULTIPLY, WKC_NUM_MUL),
	AS(VK_SUBTRACT, WKC_NUM_MINUS),
	AS(VK_ADD,      WKC_NUM_PLUS),
	AS(VK_DECIMAL,  WKC_NUM_DECIMAL),

	/* Other non-letter keys */
	AS(0xBF,  WKC_SLASH),
	AS(0xBA,  WKC_SEMICOLON),
	AS(0xBB,  WKC_EQUALS),
	AS(0xDB,  WKC_L_BRACKET),
	AS(0xDC,  WKC_BACKSLASH),
	AS(0xDD,  WKC_R_BRACKET),

	AS(0xDE,  WKC_SINGLEQUOTE),
	AS(0xBC,  WKC_COMMA),
	AS(0xBD,  WKC_MINUS),
	AS(0xBE,  WKC_PERIOD)
};

static uint MapWindowsKey(uint sym)
{
	const Win32VkMapping *map;
	uint key = 0;

	for (map = _vk_mapping; map != endof(_vk_mapping); ++map) {
		if ((uint)(sym - map->vk_from) <= map->vk_count) {
			key = sym - map->vk_from + map->map_to;
			break;
		}
	}

	if (GetAsyncKeyState(VK_SHIFT)   < 0) key |= WKC_SHIFT;
	if (GetAsyncKeyState(VK_CONTROL) < 0) key |= WKC_CTRL;
	if (GetAsyncKeyState(VK_MENU)    < 0) key |= WKC_ALT;
	return key;
}

/** Colour depth to use for fullscreen display modes. */
uint8 VideoDriver_Win32Base::GetFullscreenBpp()
{
	/* Check modes for the relevant fullscreen bpp */
	return _support8bpp != S8BPP_HARDWARE ? 32 : BlitterFactory::GetCurrentBlitter()->GetScreenDepth();
}

/**
 * Instantiate a new window.
 * @param full_screen Whether to make a full screen window or not.
 * @param resize Whether to change window size.
 * @return True if the window could be created.
 */
bool VideoDriver_Win32Base::MakeWindow(bool full_screen, bool resize)
{
	/* full_screen is whether the new window should be fullscreen,
	 * _wnd.fullscreen is whether the current window is. */
	_fullscreen = full_screen;

	/* recreate window? */
	if ((full_screen != this->fullscreen) && this->main_wnd) {
		DestroyWindow(this->main_wnd);
		this->main_wnd = 0;
	}

	if (full_screen) {
		DEVMODE settings;

		memset(&settings, 0, sizeof(settings));
		settings.dmSize = sizeof(settings);
		settings.dmFields =
			DM_BITSPERPEL |
			DM_PELSWIDTH |
			DM_PELSHEIGHT;
		settings.dmBitsPerPel = this->GetFullscreenBpp();
		settings.dmPelsWidth  = this->width_org;
		settings.dmPelsHeight = this->height_org;

		/* Check for 8 bpp support. */
		if (settings.dmBitsPerPel == 8 && ChangeDisplaySettings(&settings, CDS_FULLSCREEN | CDS_TEST) != DISP_CHANGE_SUCCESSFUL) {
			settings.dmBitsPerPel = 32;
		}

		/* Test fullscreen with current resolution, if it fails use desktop resolution. */
		if (ChangeDisplaySettings(&settings, CDS_FULLSCREEN | CDS_TEST) != DISP_CHANGE_SUCCESSFUL) {
			RECT r;
			GetWindowRect(GetDesktopWindow(), &r);
			/* Guard against recursion. If we already failed here once, just fall through to
			 * the next ChangeDisplaySettings call which will fail and error out appropriately. */
			if ((int)settings.dmPelsWidth != r.right - r.left || (int)settings.dmPelsHeight != r.bottom - r.top) {
				return this->ChangeResolution(r.right - r.left, r.bottom - r.top);
			}
		}

		if (ChangeDisplaySettings(&settings, CDS_FULLSCREEN) != DISP_CHANGE_SUCCESSFUL) {
			this->MakeWindow(false, resize);  // don't care about the result
			return false;  // the request failed
		}
	} else if (this->fullscreen) {
		/* restore display? */
		ChangeDisplaySettings(nullptr, 0);
		/* restore the resolution */
		this->width = _bck_resolution.width;
		this->height = _bck_resolution.height;
	}

	{
		RECT r;
		DWORD style, showstyle;
		int w, h;

		showstyle = SW_SHOWNORMAL;
		this->fullscreen = full_screen;
		if (this->fullscreen) {
			style = WS_POPUP;
			SetRect(&r, 0, 0, this->width_org, this->height_org);
		} else {
			style = WS_OVERLAPPEDWINDOW;
			/* On window creation, check if we were in maximize mode before */
			if (_window_maximize) showstyle = SW_SHOWMAXIMIZED;
			SetRect(&r, 0, 0, this->width, this->height);
		}

		AdjustWindowRect(&r, style, FALSE);
		w = r.right - r.left;
		h = r.bottom - r.top;

		if (this->main_wnd != nullptr) {
			if (!_window_maximize && resize) SetWindowPos(this->main_wnd, 0, 0, 0, w, h, SWP_NOACTIVATE | SWP_NOOWNERZORDER | SWP_NOZORDER | SWP_NOMOVE);
		} else {
			int x = (GetSystemMetrics(SM_CXSCREEN) - w) / 2;
			int y = (GetSystemMetrics(SM_CYSCREEN) - h) / 2;

			char window_title[64];
			seprintf(window_title, lastof(window_title), "OpenTTD %s", _openttd_revision);

			this->main_wnd = CreateWindow(L"OTTD", OTTD2FS(window_title).c_str(), style, x, y, w, h, 0, 0, GetModuleHandle(nullptr), this);
			if (this->main_wnd == nullptr) usererror("CreateWindow failed");
			ShowWindow(this->main_wnd, showstyle);
		}
	}

	BlitterFactory::GetCurrentBlitter()->PostResize();

	GameSizeChanged();
	return true;
}

/** Forward key presses to the window system. */
static LRESULT HandleCharMsg(uint keycode, WChar charcode)
{
	static WChar prev_char = 0;

	/* Did we get a lead surrogate? If yes, store and exit. */
	if (Utf16IsLeadSurrogate(charcode)) {
		if (prev_char != 0) DEBUG(driver, 1, "Got two UTF-16 lead surrogates, dropping the first one");
		prev_char = charcode;
		return 0;
	}

	/* Stored lead surrogate and incoming trail surrogate? Combine and forward to input handling. */
	if (prev_char != 0) {
		if (Utf16IsTrailSurrogate(charcode)) {
			charcode = Utf16DecodeSurrogate(prev_char, charcode);
		} else {
			DEBUG(driver, 1, "Got an UTF-16 lead surrogate without a trail surrogate, dropping the lead surrogate");
		}
	}
	prev_char = 0;

	HandleKeypress(keycode, charcode);

	return 0;
}

/** Should we draw the composition string ourself, i.e is this a normal IME? */
static bool DrawIMECompositionString()
{
	return (_imm_props & IME_PROP_AT_CARET) && !(_imm_props & IME_PROP_SPECIAL_UI);
}

/** Set position of the composition window to the caret position. */
static void SetCompositionPos(HWND hwnd)
{
	HIMC hIMC = ImmGetContext(hwnd);
	if (hIMC != NULL) {
		COMPOSITIONFORM cf;
		cf.dwStyle = CFS_POINT;

		if (EditBoxInGlobalFocus()) {
			/* Get caret position. */
			Point pt = _focused_window->GetCaretPosition();
			cf.ptCurrentPos.x = _focused_window->left + pt.x;
			cf.ptCurrentPos.y = _focused_window->top  + pt.y;
		} else {
			cf.ptCurrentPos.x = 0;
			cf.ptCurrentPos.y = 0;
		}
		ImmSetCompositionWindow(hIMC, &cf);
	}
	ImmReleaseContext(hwnd, hIMC);
}

/** Set the position of the candidate window. */
static void SetCandidatePos(HWND hwnd)
{
	HIMC hIMC = ImmGetContext(hwnd);
	if (hIMC != NULL) {
		CANDIDATEFORM cf;
		cf.dwIndex = 0;
		cf.dwStyle = CFS_EXCLUDE;

		if (EditBoxInGlobalFocus()) {
			Point pt = _focused_window->GetCaretPosition();
			cf.ptCurrentPos.x = _focused_window->left + pt.x;
			cf.ptCurrentPos.y = _focused_window->top  + pt.y;
			if (_focused_window->window_class == WC_CONSOLE) {
				cf.rcArea.left   = _focused_window->left;
				cf.rcArea.top    = _focused_window->top;
				cf.rcArea.right  = _focused_window->left + _focused_window->width;
				cf.rcArea.bottom = _focused_window->top  + _focused_window->height;
			} else {
				cf.rcArea.left   = _focused_window->left + _focused_window->nested_focus->pos_x;
				cf.rcArea.top    = _focused_window->top  + _focused_window->nested_focus->pos_y;
				cf.rcArea.right  = cf.rcArea.left + _focused_window->nested_focus->current_x;
				cf.rcArea.bottom = cf.rcArea.top  + _focused_window->nested_focus->current_y;
			}
		} else {
			cf.ptCurrentPos.x = 0;
			cf.ptCurrentPos.y = 0;
			SetRectEmpty(&cf.rcArea);
		}
		ImmSetCandidateWindow(hIMC, &cf);
	}
	ImmReleaseContext(hwnd, hIMC);
}

/** Handle WM_IME_COMPOSITION messages. */
static LRESULT HandleIMEComposition(HWND hwnd, WPARAM wParam, LPARAM lParam)
{
	HIMC hIMC = ImmGetContext(hwnd);

	if (hIMC != NULL) {
		if (lParam & GCS_RESULTSTR) {
			/* Read result string from the IME. */
			LONG len = ImmGetCompositionString(hIMC, GCS_RESULTSTR, nullptr, 0); // Length is always in bytes, even in UNICODE build.
			wchar_t *str = (wchar_t *)_alloca(len + sizeof(wchar_t));
			len = ImmGetCompositionString(hIMC, GCS_RESULTSTR, str, len);
			str[len / sizeof(wchar_t)] = '\0';

			/* Transmit text to windowing system. */
			if (len > 0) {
				HandleTextInput(nullptr, true); // Clear marked string.
				HandleTextInput(FS2OTTD(str).c_str());
			}
			SetCompositionPos(hwnd);

			/* Don't pass the result string on to the default window proc. */
			lParam &= ~(GCS_RESULTSTR | GCS_RESULTCLAUSE | GCS_RESULTREADCLAUSE | GCS_RESULTREADSTR);
		}

		if ((lParam & GCS_COMPSTR) && DrawIMECompositionString()) {
			/* Read composition string from the IME. */
			LONG len = ImmGetCompositionString(hIMC, GCS_COMPSTR, nullptr, 0); // Length is always in bytes, even in UNICODE build.
			wchar_t *str = (wchar_t *)_alloca(len + sizeof(wchar_t));
			len = ImmGetCompositionString(hIMC, GCS_COMPSTR, str, len);
			str[len / sizeof(wchar_t)] = '\0';

			if (len > 0) {
				static char utf8_buf[1024];
				convert_from_fs(str, utf8_buf, lengthof(utf8_buf));

				/* Convert caret position from bytes in the input string to a position in the UTF-8 encoded string. */
				LONG caret_bytes = ImmGetCompositionString(hIMC, GCS_CURSORPOS, nullptr, 0);
				const char *caret = utf8_buf;
				for (const wchar_t *c = str; *c != '\0' && *caret != '\0' && caret_bytes > 0; c++, caret_bytes--) {
					/* Skip DBCS lead bytes or leading surrogates. */
					if (Utf16IsLeadSurrogate(*c)) {
						c++;
						caret_bytes--;
					}
					Utf8Consume(&caret);
				}

				HandleTextInput(utf8_buf, true, caret);
			} else {
				HandleTextInput(nullptr, true);
			}

			lParam &= ~(GCS_COMPSTR | GCS_COMPATTR | GCS_COMPCLAUSE | GCS_CURSORPOS | GCS_DELTASTART);
		}
	}
	ImmReleaseContext(hwnd, hIMC);

	return lParam != 0 ? DefWindowProc(hwnd, WM_IME_COMPOSITION, wParam, lParam) : 0;
}

/** Clear the current composition string. */
static void CancelIMEComposition(HWND hwnd)
{
	HIMC hIMC = ImmGetContext(hwnd);
	if (hIMC != NULL) ImmNotifyIME(hIMC, NI_COMPOSITIONSTR, CPS_CANCEL, 0);
	ImmReleaseContext(hwnd, hIMC);
	/* Clear any marked string from the current edit box. */
	HandleTextInput(nullptr, true);
}

LRESULT CALLBACK WndProcGdi(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
	static uint32 keycode = 0;
	static bool console = false;

	VideoDriver_Win32Base *video_driver = (VideoDriver_Win32Base *)GetWindowLongPtr(hwnd, GWLP_USERDATA);

	switch (msg) {
		case WM_CREATE:
			SetWindowLongPtr(hwnd, GWLP_USERDATA, (LONG_PTR)((LPCREATESTRUCT)lParam)->lpCreateParams);
			_cursor.in_window = false; // Win32 has mouse tracking.
			SetCompositionPos(hwnd);
			_imm_props = ImmGetProperty(GetKeyboardLayout(0), IGP_PROPERTY);
			break;

		case WM_PAINT: {
			RECT r;
			GetUpdateRect(hwnd, &r, FALSE);
			video_driver->MakeDirty(r.left, r.top, r.right - r.left, r.bottom - r.top);

			ValidateRect(hwnd, nullptr);
			return 0;
		}

		case WM_PALETTECHANGED:
			if ((HWND)wParam == hwnd) return 0;
			FALLTHROUGH;

		case WM_QUERYNEWPALETTE:
			video_driver->PaletteChanged(hwnd);
			return 0;

		case WM_CLOSE:
			HandleExitGameRequest();
			return 0;

		case WM_DESTROY:
			if (_window_maximize) _cur_resolution = _bck_resolution;
			return 0;

		case WM_LBUTTONDOWN:
			SetCapture(hwnd);
			_left_button_down = true;
			HandleMouseEvents();
			return 0;

		case WM_LBUTTONUP:
			ReleaseCapture();
			_left_button_down = false;
			_left_button_clicked = false;
			HandleMouseEvents();
			return 0;

		case WM_RBUTTONDOWN:
			SetCapture(hwnd);
			_right_button_down = true;
			_right_button_clicked = true;
			HandleMouseEvents();
			return 0;

		case WM_RBUTTONUP:
			ReleaseCapture();
			_right_button_down = false;
			HandleMouseEvents();
			return 0;

		case WM_MOUSELEAVE:
			UndrawMouseCursor();
			_cursor.in_window = false;

			if (!_left_button_down && !_right_button_down) MyShowCursor(true);
			return 0;

		case WM_MOUSEMOVE: {
			int x = (int16)LOWORD(lParam);
			int y = (int16)HIWORD(lParam);

			/* If the mouse was not in the window and it has moved it means it has
			 * come into the window, so start drawing the mouse. Also start
			 * tracking the mouse for exiting the window */
			if (!_cursor.in_window) {
				_cursor.in_window = true;
				TRACKMOUSEEVENT tme;
				tme.cbSize = sizeof(tme);
				tme.dwFlags = TME_LEAVE;
				tme.hwndTrack = hwnd;

				TrackMouseEvent(&tme);
			}

			if (_cursor.fix_at) {
				/* Get all queued mouse events now in case we have to warp the cursor. In the
				 * end, we only care about the current mouse position and not bygone events. */
				MSG m;
				while (PeekMessage(&m, hwnd, WM_MOUSEMOVE, WM_MOUSEMOVE, PM_REMOVE | PM_NOYIELD | PM_QS_INPUT)) {
					x = (int16)LOWORD(m.lParam);
					y = (int16)HIWORD(m.lParam);
				}
			}

			if (_cursor.UpdateCursorPosition(x, y, false)) {
				POINT pt;
				pt.x = _cursor.pos.x;
				pt.y = _cursor.pos.y;
				ClientToScreen(hwnd, &pt);
				SetCursorPos(pt.x, pt.y);
			}
			MyShowCursor(false);
			HandleMouseEvents();
			return 0;
		}

		case WM_INPUTLANGCHANGE:
			_imm_props = ImmGetProperty(GetKeyboardLayout(0), IGP_PROPERTY);
			break;

		case WM_IME_SETCONTEXT:
			/* Don't show the composition window if we draw the string ourself. */
			if (DrawIMECompositionString()) lParam &= ~ISC_SHOWUICOMPOSITIONWINDOW;
			break;

		case WM_IME_STARTCOMPOSITION:
			SetCompositionPos(hwnd);
			if (DrawIMECompositionString()) return 0;
			break;

		case WM_IME_COMPOSITION:
			return HandleIMEComposition(hwnd, wParam, lParam);

		case WM_IME_ENDCOMPOSITION:
			/* Clear any pending composition string. */
			HandleTextInput(nullptr, true);
			if (DrawIMECompositionString()) return 0;
			break;

		case WM_IME_NOTIFY:
			if (wParam == IMN_OPENCANDIDATE) SetCandidatePos(hwnd);
			break;

		case WM_DEADCHAR:
			console = GB(lParam, 16, 8) == 41;
			return 0;

		case WM_CHAR: {
			uint scancode = GB(lParam, 16, 8);
			uint charcode = wParam;

			/* If the console key is a dead-key, we need to press it twice to get a WM_CHAR message.
			 * But we then get two WM_CHAR messages, so ignore the first one */
			if (console && scancode == 41) {
				console = false;
				return 0;
			}

			/* IMEs and other input methods sometimes send a WM_CHAR without a WM_KEYDOWN,
			 * clear the keycode so a previous WM_KEYDOWN doesn't become 'stuck'. */
			uint cur_keycode = keycode;
			keycode = 0;

			return HandleCharMsg(cur_keycode, charcode);
		}

		case WM_KEYDOWN: {
			/* No matter the keyboard layout, we will map the '~' to the console. */
			uint scancode = GB(lParam, 16, 8);
			keycode = scancode == 41 ? (uint)WKC_BACKQUOTE : MapWindowsKey(wParam);

			uint charcode = MapVirtualKey(wParam, MAPVK_VK_TO_CHAR);

			/* No character translation? */
			if (charcode == 0) {
				HandleKeypress(keycode, 0);
				return 0;
			}

			/* If an edit box is in focus, wait for the corresponding WM_CHAR message. */
			if (!EditBoxInGlobalFocus()) {
				/* Is the console key a dead key? If yes, ignore the first key down event. */
				if (HasBit(charcode, 31) && !console) {
					if (scancode == 41) {
						console = true;
						return 0;
					}
				}
				console = false;

				/* IMEs and other input methods sometimes send a WM_CHAR without a WM_KEYDOWN,
				 * clear the keycode so a previous WM_KEYDOWN doesn't become 'stuck'. */
				uint cur_keycode = keycode;
				keycode = 0;

				return HandleCharMsg(cur_keycode, LOWORD(charcode));
			}

			return 0;
		}

		case WM_SYSKEYDOWN: // user presses F10 or Alt, both activating the title-menu
			switch (wParam) {
				case VK_RETURN:
				case 'F': // Full Screen on ALT + ENTER/F
					ToggleFullScreen(!video_driver->fullscreen);
					return 0;

				case VK_MENU: // Just ALT
					return 0; // do nothing

				case VK_F10: // F10, ignore activation of menu
					HandleKeypress(MapWindowsKey(wParam), 0);
					return 0;

				default: // ALT in combination with something else
					HandleKeypress(MapWindowsKey(wParam), 0);
					break;
			}
			break;

		case WM_SIZE:
			if (wParam != SIZE_MINIMIZED) {
				/* Set maximized flag when we maximize (obviously), but also when we
				 * switched to fullscreen from a maximized state */
				_window_maximize = (wParam == SIZE_MAXIMIZED || (_window_maximize && _fullscreen));
				if (_window_maximize || _fullscreen) _bck_resolution = _cur_resolution;
				video_driver->ClientSizeChanged(LOWORD(lParam), HIWORD(lParam));
			}
			return 0;

		case WM_SIZING: {
			RECT *r = (RECT*)lParam;
			RECT r2;
			int w, h;

			SetRect(&r2, 0, 0, 0, 0);
			AdjustWindowRect(&r2, GetWindowLong(hwnd, GWL_STYLE), FALSE);

			w = r->right - r->left - (r2.right - r2.left);
			h = r->bottom - r->top - (r2.bottom - r2.top);
			w = std::max(w, 64);
			h = std::max(h, 64);
			SetRect(&r2, 0, 0, w, h);

			AdjustWindowRect(&r2, GetWindowLong(hwnd, GWL_STYLE), FALSE);
			w = r2.right - r2.left;
			h = r2.bottom - r2.top;

			switch (wParam) {
				case WMSZ_BOTTOM:
					r->bottom = r->top + h;
					break;

				case WMSZ_BOTTOMLEFT:
					r->bottom = r->top + h;
					r->left = r->right - w;
					break;

				case WMSZ_BOTTOMRIGHT:
					r->bottom = r->top + h;
					r->right = r->left + w;
					break;

				case WMSZ_LEFT:
					r->left = r->right - w;
					break;

				case WMSZ_RIGHT:
					r->right = r->left + w;
					break;

				case WMSZ_TOP:
					r->top = r->bottom - h;
					break;

				case WMSZ_TOPLEFT:
					r->top = r->bottom - h;
					r->left = r->right - w;
					break;

				case WMSZ_TOPRIGHT:
					r->top = r->bottom - h;
					r->right = r->left + w;
					break;
			}
			return TRUE;
		}

/* needed for wheel */
#if !defined(WM_MOUSEWHEEL)
# define WM_MOUSEWHEEL 0x020A
#endif  /* WM_MOUSEWHEEL */
#if !defined(GET_WHEEL_DELTA_WPARAM)
# define GET_WHEEL_DELTA_WPARAM(wparam) ((short)HIWORD(wparam))
#endif  /* GET_WHEEL_DELTA_WPARAM */

		case WM_MOUSEWHEEL: {
			int delta = GET_WHEEL_DELTA_WPARAM(wParam);

			if (delta < 0) {
				_cursor.wheel++;
			} else if (delta > 0) {
				_cursor.wheel--;
			}
			HandleMouseEvents();
			return 0;
		}

		case WM_SETFOCUS:
			video_driver->has_focus = true;
			SetCompositionPos(hwnd);
			break;

		case WM_KILLFOCUS:
			video_driver->has_focus = false;
			break;

		case WM_ACTIVATE: {
			/* Don't do anything if we are closing openttd */
			if (_exit_game) break;

			bool active = (LOWORD(wParam) != WA_INACTIVE);
			bool minimized = (HIWORD(wParam) != 0);
			if (video_driver->fullscreen) {
				if (active && minimized) {
					/* Restore the game window */
					Dimension d = _bck_resolution; // Save current non-fullscreen window size as it will be overwritten by ShowWindow.
					ShowWindow(hwnd, SW_RESTORE);
					_bck_resolution = d;
					video_driver->MakeWindow(true);
				} else if (!active && !minimized) {
					/* Minimise the window and restore desktop */
					ShowWindow(hwnd, SW_MINIMIZE);
					ChangeDisplaySettings(nullptr, 0);
				}
			}
			break;
		}
	}

	return DefWindowProc(hwnd, msg, wParam, lParam);
}

static void RegisterWndClass()
{
	static bool registered = false;

	if (registered) return;

	HINSTANCE hinst = GetModuleHandle(nullptr);
	WNDCLASS wnd = {
		CS_OWNDC,
		WndProcGdi,
		0,
		0,
		hinst,
		LoadIcon(hinst, MAKEINTRESOURCE(100)),
		LoadCursor(nullptr, IDC_ARROW),
		0,
		0,
		L"OTTD"
	};

	registered = true;
	if (!RegisterClass(&wnd)) usererror("RegisterClass failed");
}

static const Dimension default_resolutions[] = {
	{  640,  480 },
	{  800,  600 },
	{ 1024,  768 },
	{ 1152,  864 },
	{ 1280,  800 },
	{ 1280,  960 },
	{ 1280, 1024 },
	{ 1400, 1050 },
	{ 1600, 1200 },
	{ 1680, 1050 },
	{ 1920, 1200 }
};

static void FindResolutions(uint8 bpp)
{
	_resolutions.clear();

	DEVMODE dm;
	for (uint i = 0; EnumDisplaySettings(nullptr, i, &dm) != 0; i++) {
		if (dm.dmBitsPerPel != bpp || dm.dmPelsWidth < 640 || dm.dmPelsHeight < 480) continue;
		if (std::find(_resolutions.begin(), _resolutions.end(), Dimension(dm.dmPelsWidth, dm.dmPelsHeight)) != _resolutions.end()) continue;
		_resolutions.emplace_back(dm.dmPelsWidth, dm.dmPelsHeight);
	}

	/* We have found no resolutions, show the default list */
	if (_resolutions.empty()) {
		_resolutions.assign(std::begin(default_resolutions), std::end(default_resolutions));
	}

	SortResolutions();
}

void VideoDriver_Win32Base::Initialize()
{
	this->UpdateAutoResolution();

	RegisterWndClass();
	FindResolutions(this->GetFullscreenBpp());

	/* fullscreen uses those */
	this->width  = this->width_org  = _cur_resolution.width;
	this->height = this->height_org = _cur_resolution.height;

	DEBUG(driver, 2, "Resolution for display: %ux%u", _cur_resolution.width, _cur_resolution.height);
}

void VideoDriver_Win32Base::Stop()
{
	DestroyWindow(this->main_wnd);

	if (this->fullscreen) ChangeDisplaySettings(nullptr, 0);
	MyShowCursor(true);
}
void VideoDriver_Win32Base::MakeDirty(int left, int top, int width, int height)
{
	Rect r = {left, top, left + width, top + height};
	this->dirty_rect = BoundingRect(this->dirty_rect, r);
}

void VideoDriver_Win32Base::CheckPaletteAnim()
{
	if (_cur_palette.count_dirty == 0) return;

	_local_palette = _cur_palette;
	this->MakeDirty(0, 0, _screen.width, _screen.height);
}

void VideoDriver_Win32Base::InputLoop()
{
	bool old_ctrl_pressed = _ctrl_pressed;

	_ctrl_pressed = this->has_focus && GetAsyncKeyState(VK_CONTROL) < 0;
	_shift_pressed = this->has_focus && GetAsyncKeyState(VK_SHIFT) < 0;

#if defined(_DEBUG)
	this->fast_forward_key_pressed = _shift_pressed;
#else
	/* Speedup when pressing tab, except when using ALT+TAB
	 * to switch to another application. */
	this->fast_forward_key_pressed = this->has_focus && GetAsyncKeyState(VK_TAB) < 0 && GetAsyncKeyState(VK_MENU) >= 0;
#endif

	/* Determine which directional keys are down. */
	if (this->has_focus) {
		_dirkeys =
			(GetAsyncKeyState(VK_LEFT) < 0 ? 1 : 0) +
			(GetAsyncKeyState(VK_UP) < 0 ? 2 : 0) +
			(GetAsyncKeyState(VK_RIGHT) < 0 ? 4 : 0) +
			(GetAsyncKeyState(VK_DOWN) < 0 ? 8 : 0);
	} else {
		_dirkeys = 0;
	}

	if (old_ctrl_pressed != _ctrl_pressed) HandleCtrlChanged();
}

bool VideoDriver_Win32Base::PollEvent()
{
	MSG mesg;

	if (!PeekMessage(&mesg, nullptr, 0, 0, PM_REMOVE)) return false;

	/* Convert key messages to char messages if we want text input. */
	if (EditBoxInGlobalFocus()) TranslateMessage(&mesg);
	DispatchMessage(&mesg);

	return true;
}

void VideoDriver_Win32Base::MainLoop()
{
	this->StartGameThread();

	for (;;) {
		if (_exit_game) break;

		this->Tick();
		this->SleepTillNextTick();
	}

	this->StopGameThread();
}

void VideoDriver_Win32Base::ClientSizeChanged(int w, int h, bool force)
{
	/* Allocate backing store of the new size. */
	if (this->AllocateBackingStore(w, h, force)) {
		/* Mark all palette colours dirty. */
		_cur_palette.first_dirty = 0;
		_cur_palette.count_dirty = 256;
		_local_palette = _cur_palette;

		BlitterFactory::GetCurrentBlitter()->PostResize();

		GameSizeChanged();
	}
}

bool VideoDriver_Win32Base::ChangeResolution(int w, int h)
{
	if (_window_maximize) ShowWindow(this->main_wnd, SW_SHOWNORMAL);

	this->width = this->width_org = w;
	this->height = this->height_org = h;

	return this->MakeWindow(_fullscreen); // _wnd.fullscreen screws up ingame resolution switching
}

bool VideoDriver_Win32Base::ToggleFullscreen(bool full_screen)
{
	bool res = this->MakeWindow(full_screen);

	InvalidateWindowClassesData(WC_GAME_OPTIONS, 3);
	return res;
}

void VideoDriver_Win32Base::EditBoxLostFocus()
{
	CancelIMEComposition(this->main_wnd);
	SetCompositionPos(this->main_wnd);
	SetCandidatePos(this->main_wnd);
}

std::vector<int> VideoDriver_Win32Base::GetListOfMonitorRefreshRates()
{
	std::vector<int> rates = {};
	EnumDisplayMonitors(nullptr, nullptr, [](HMONITOR hMonitor, HDC hDC, LPRECT rc, LPARAM data) -> BOOL {
		auto &list = *reinterpret_cast<std::vector<int>*>(data);

		MONITORINFOEX monitorInfo = {};
		monitorInfo.cbSize = sizeof(MONITORINFOEX);
		GetMonitorInfo(hMonitor, &monitorInfo);

		DEVMODE devMode = {};
		devMode.dmSize = sizeof(DEVMODE);
		devMode.dmDriverExtra = 0;
		EnumDisplaySettings(monitorInfo.szDevice, ENUM_CURRENT_SETTINGS, &devMode);

		if (devMode.dmDisplayFrequency != 0) list.push_back(devMode.dmDisplayFrequency);
		return true;
	}, reinterpret_cast<LPARAM>(&rates));
	return rates;
}

Dimension VideoDriver_Win32Base::GetScreenSize() const
{
	return { static_cast<uint>(GetSystemMetrics(SM_CXSCREEN)), static_cast<uint>(GetSystemMetrics(SM_CYSCREEN)) };
}

float VideoDriver_Win32Base::GetDPIScale()
{
	typedef UINT (WINAPI *PFNGETDPIFORWINDOW)(HWND hwnd);
	typedef UINT (WINAPI *PFNGETDPIFORSYSTEM)(VOID);
	typedef HRESULT (WINAPI *PFNGETDPIFORMONITOR)(HMONITOR hMonitor, int dpiType, UINT *dpiX, UINT *dpiY);

	static PFNGETDPIFORWINDOW _GetDpiForWindow = nullptr;
	static PFNGETDPIFORSYSTEM _GetDpiForSystem = nullptr;
	static PFNGETDPIFORMONITOR _GetDpiForMonitor = nullptr;

	static bool init_done = false;
	if (!init_done) {
		init_done = true;

		_GetDpiForWindow = (PFNGETDPIFORWINDOW)GetProcAddress(GetModuleHandle(L"User32"), "GetDpiForWindow");
		_GetDpiForSystem = (PFNGETDPIFORSYSTEM)GetProcAddress(GetModuleHandle(L"User32"), "GetDpiForSystem");
		_GetDpiForMonitor = (PFNGETDPIFORMONITOR)GetProcAddress(LoadLibrary(L"Shcore.dll"), "GetDpiForMonitor");
	}

	UINT cur_dpi = 0;

	if (cur_dpi == 0 && _GetDpiForWindow != nullptr && this->main_wnd != nullptr) {
		/* Per window DPI is supported since Windows 10 Ver 1607. */
		cur_dpi = _GetDpiForWindow(this->main_wnd);
	}
	if (cur_dpi == 0 && _GetDpiForMonitor != nullptr && this->main_wnd != nullptr) {
		/* Per monitor is supported since Windows 8.1. */
		UINT dpiX, dpiY;
		if (SUCCEEDED(_GetDpiForMonitor(MonitorFromWindow(this->main_wnd, MONITOR_DEFAULTTOPRIMARY), 0 /* MDT_EFFECTIVE_DPI */, &dpiX, &dpiY))) {
			cur_dpi = dpiX; // X and Y are always identical.
		}
	}
	if (cur_dpi == 0 && _GetDpiForSystem != nullptr) {
		/* Fall back to system DPI. */
		cur_dpi = _GetDpiForSystem();
	}

	return cur_dpi > 0 ? cur_dpi / 96.0f : 1.0f; // Default Windows DPI value is 96.
}

bool VideoDriver_Win32Base::LockVideoBuffer()
{
	if (this->buffer_locked) return false;
	this->buffer_locked = true;

	_screen.dst_ptr = this->GetVideoPointer();
	assert(_screen.dst_ptr != nullptr);

	return true;
}

void VideoDriver_Win32Base::UnlockVideoBuffer()
{
	assert(_screen.dst_ptr != nullptr);
	if (_screen.dst_ptr != nullptr) {
		/* Hand video buffer back to the drawing backend. */
		this->ReleaseVideoPointer();
		_screen.dst_ptr = nullptr;
	}

	this->buffer_locked = false;
}


static FVideoDriver_Win32GDI iFVideoDriver_Win32GDI;

const char *VideoDriver_Win32GDI::Start(const StringList &param)
{
	if (BlitterFactory::GetCurrentBlitter()->GetScreenDepth() == 0) return "Only real blitters supported";

	this->Initialize();

	this->MakePalette();
	this->AllocateBackingStore(_cur_resolution.width, _cur_resolution.height);
	this->MakeWindow(_fullscreen);

	MarkWholeScreenDirty();

	this->is_game_threaded = !GetDriverParamBool(param, "no_threads") && !GetDriverParamBool(param, "no_thread");

	return nullptr;
}

void VideoDriver_Win32GDI::Stop()
{
	DeleteObject(this->gdi_palette);
	DeleteObject(this->dib_sect);

	this->VideoDriver_Win32Base::Stop();
}

bool VideoDriver_Win32GDI::AllocateBackingStore(int w, int h, bool force)
{
	uint bpp = BlitterFactory::GetCurrentBlitter()->GetScreenDepth();

	w = std::max(w, 64);
	h = std::max(h, 64);

	if (!force && w == _screen.width && h == _screen.height) return false;

	BITMAPINFO *bi = (BITMAPINFO *)alloca(sizeof(BITMAPINFOHEADER) + sizeof(RGBQUAD) * 256);
	memset(bi, 0, sizeof(BITMAPINFOHEADER) + sizeof(RGBQUAD) * 256);
	bi->bmiHeader.biSize = sizeof(BITMAPINFOHEADER);

	bi->bmiHeader.biWidth = this->width = w;
	bi->bmiHeader.biHeight = -(this->height = h);

	bi->bmiHeader.biPlanes = 1;
	bi->bmiHeader.biBitCount = bpp;
	bi->bmiHeader.biCompression = BI_RGB;

	if (this->dib_sect) DeleteObject(this->dib_sect);

	HDC dc = GetDC(0);
	this->dib_sect = CreateDIBSection(dc, bi, DIB_RGB_COLORS, (VOID **)&this->buffer_bits, nullptr, 0);
	if (this->dib_sect == nullptr) usererror("CreateDIBSection failed");
	ReleaseDC(0, dc);

	_screen.width = w;
	_screen.pitch = (bpp == 8) ? Align(w, 4) : w;
	_screen.height = h;
	_screen.dst_ptr = this->GetVideoPointer();

	return true;
}

bool VideoDriver_Win32GDI::AfterBlitterChange()
{
	assert(BlitterFactory::GetCurrentBlitter()->GetScreenDepth() != 0);
	return this->AllocateBackingStore(_screen.width, _screen.height, true) && this->MakeWindow(_fullscreen, false);
}

void VideoDriver_Win32GDI::MakePalette()
{
	_cur_palette.first_dirty = 0;
	_cur_palette.count_dirty = 256;
	_local_palette = _cur_palette;

	LOGPALETTE *pal = (LOGPALETTE*)alloca(sizeof(LOGPALETTE) + (256 - 1) * sizeof(PALETTEENTRY));

	pal->palVersion = 0x300;
	pal->palNumEntries = 256;

	for (uint i = 0; i != 256; i++) {
		pal->palPalEntry[i].peRed   = _local_palette.palette[i].r;
		pal->palPalEntry[i].peGreen = _local_palette.palette[i].g;
		pal->palPalEntry[i].peBlue  = _local_palette.palette[i].b;
		pal->palPalEntry[i].peFlags = 0;

	}
	this->gdi_palette = CreatePalette(pal);
	if (this->gdi_palette == nullptr) usererror("CreatePalette failed!\n");
}

void VideoDriver_Win32GDI::UpdatePalette(HDC dc, uint start, uint count)
{
	RGBQUAD rgb[256];

	for (uint i = 0; i != count; i++) {
		rgb[i].rgbRed   = _local_palette.palette[start + i].r;
		rgb[i].rgbGreen = _local_palette.palette[start + i].g;
		rgb[i].rgbBlue  = _local_palette.palette[start + i].b;
		rgb[i].rgbReserved = 0;
	}

	SetDIBColorTable(dc, start, count, rgb);
}

void VideoDriver_Win32GDI::PaletteChanged(HWND hWnd)
{
	HDC hDC = GetWindowDC(hWnd);
	HPALETTE hOldPalette = SelectPalette(hDC, this->gdi_palette, FALSE);
	UINT nChanged = RealizePalette(hDC);

	SelectPalette(hDC, hOldPalette, TRUE);
	ReleaseDC(hWnd, hDC);
	if (nChanged != 0) this->MakeDirty(0, 0, _screen.width, _screen.height);
}

void VideoDriver_Win32GDI::Paint()
{
	PerformanceMeasurer framerate(PFE_VIDEO);

	if (IsEmptyRect(this->dirty_rect)) return;

	HDC dc = GetDC(this->main_wnd);
	HDC dc2 = CreateCompatibleDC(dc);

	HBITMAP old_bmp = (HBITMAP)SelectObject(dc2, this->dib_sect);
	HPALETTE old_palette = SelectPalette(dc, this->gdi_palette, FALSE);

	if (_cur_palette.count_dirty != 0) {
		Blitter *blitter = BlitterFactory::GetCurrentBlitter();

		switch (blitter->UsePaletteAnimation()) {
			case Blitter::PALETTE_ANIMATION_VIDEO_BACKEND:
				this->UpdatePalette(dc2, _local_palette.first_dirty, _local_palette.count_dirty);
				break;

			case Blitter::PALETTE_ANIMATION_BLITTER: {
				blitter->PaletteAnimate(_local_palette);
				break;
			}

			case Blitter::PALETTE_ANIMATION_NONE:
				break;

			default:
				NOT_REACHED();
		}
		_cur_palette.count_dirty = 0;
	}

	BitBlt(dc, 0, 0, this->width, this->height, dc2, 0, 0, SRCCOPY);
	SelectPalette(dc, old_palette, TRUE);
	SelectObject(dc2, old_bmp);
	DeleteDC(dc2);

	ReleaseDC(this->main_wnd, dc);

	this->dirty_rect = {};
}

#ifdef _DEBUG
/* Keep this function here..
 * It allows you to redraw the screen from within the MSVC debugger */
/* static */ int VideoDriver_Win32GDI::RedrawScreenDebug()
{
	static int _fooctr;

	VideoDriver_Win32GDI *drv = static_cast<VideoDriver_Win32GDI *>(VideoDriver::GetInstance());

	_screen.dst_ptr = drv->GetVideoPointer();
	UpdateWindows();

	drv->Paint();
	GdiFlush();

	return _fooctr++;
}
#endif

#ifdef WITH_OPENGL

#include <GL/gl.h>
#include "../3rdparty/opengl/glext.h"
#include "../3rdparty/opengl/wglext.h"
#include "opengl.h"

#ifndef PFD_SUPPORT_COMPOSITION
#	define PFD_SUPPORT_COMPOSITION 0x00008000
#endif

static PFNWGLCREATECONTEXTATTRIBSARBPROC _wglCreateContextAttribsARB = nullptr;
static PFNWGLSWAPINTERVALEXTPROC _wglSwapIntervalEXT = nullptr;
static bool _hasWGLARBCreateContextProfile = false; ///< Is WGL_ARB_create_context_profile supported?

/** Platform-specific callback to get an OpenGL function pointer. */
static OGLProc GetOGLProcAddressCallback(const char *proc)
{
	OGLProc ret = reinterpret_cast<OGLProc>(wglGetProcAddress(proc));
	if (ret == nullptr) {
		/* Non-extension GL function? Try normal loading. */
		ret = reinterpret_cast<OGLProc>(GetProcAddress(GetModuleHandle(L"opengl32"), proc));
	}
	return ret;
}

/**
 * Set the pixel format of a window-
 * @param dc Device context to set the pixel format of.
 * @param fullscreen Should the pixel format be used for fullscreen drawing?
 * @return nullptr on success, error message otherwise.
 */
static const char *SelectPixelFormat(HDC dc, bool fullscreen)
{
	PIXELFORMATDESCRIPTOR pfd = {
		sizeof(PIXELFORMATDESCRIPTOR), // Size of this struct.
		1,                             // Version of this struct.
		PFD_DRAW_TO_WINDOW |           // Require window support.
		PFD_SUPPORT_OPENGL |           // Require OpenGL support.
		PFD_DOUBLEBUFFER   |           // Use double buffering.
		PFD_DEPTH_DONTCARE,
		PFD_TYPE_RGBA,                 // Request RGBA format.
		24,                            // 24 bpp (excluding alpha).
		0, 0, 0, 0, 0, 0, 0, 0,        // Colour bits and shift ignored.
		0, 0, 0, 0, 0,                 // No accumulation buffer.
		0, 0,                          // No depth/stencil buffer.
		0,                             // No aux buffers.
		PFD_MAIN_PLANE,                // Main layer.
		0, 0, 0, 0                     // Ignored/reserved.
	};

	if (IsWindowsVistaOrGreater()) pfd.dwFlags |= PFD_SUPPORT_COMPOSITION; // Make OpenTTD compatible with Aero.

	/* Choose a suitable pixel format. */
	int format = ChoosePixelFormat(dc, &pfd);
	if (format == 0) return "No suitable pixel format found";
	if (!SetPixelFormat(dc, format, &pfd)) return "Can't set pixel format";

	return nullptr;
}

/** Bind all WGL extension functions we need. */
static void LoadWGLExtensions()
{
	/* Querying the supported WGL extensions and loading the matching
	 * functions requires a valid context, even for the extensions
	 * regarding context creation. To get around this, we create
	 * a dummy window with a dummy context. The extension functions
	 * remain valid even after this context is destroyed. */
	HWND wnd = CreateWindow(_T("STATIC"), _T("dummy"), WS_OVERLAPPEDWINDOW, 0, 0, 0, 0, nullptr, nullptr, GetModuleHandle(nullptr), nullptr);
	HDC dc = GetDC(wnd);

	/* Set pixel format of the window. */
	if (SelectPixelFormat(dc, false) == nullptr) {
		/* Create rendering context. */
		HGLRC rc = wglCreateContext(dc);
		if (rc != nullptr) {
			wglMakeCurrent(dc, rc);

			/* Get list of WGL extensions. */
			PFNWGLGETEXTENSIONSSTRINGARBPROC wglGetExtensionsStringARB = (PFNWGLGETEXTENSIONSSTRINGARBPROC)wglGetProcAddress("wglGetExtensionsStringARB");
			if (wglGetExtensionsStringARB != nullptr) {
				const char *wgl_exts = wglGetExtensionsStringARB(dc);
				/* Bind supported functions. */
				if (FindStringInExtensionList(wgl_exts, "WGL_ARB_create_context") != nullptr) {
					_wglCreateContextAttribsARB = (PFNWGLCREATECONTEXTATTRIBSARBPROC)wglGetProcAddress("wglCreateContextAttribsARB");
				}
				_hasWGLARBCreateContextProfile = FindStringInExtensionList(wgl_exts, "WGL_ARB_create_context_profile") != nullptr;
				if (FindStringInExtensionList(wgl_exts, "WGL_EXT_swap_control") != nullptr) {
					_wglSwapIntervalEXT = (PFNWGLSWAPINTERVALEXTPROC)wglGetProcAddress("wglSwapIntervalEXT");
				}
			}

			wglMakeCurrent(nullptr, nullptr);
			wglDeleteContext(rc);
		}
	}

	ReleaseDC(wnd, dc);
	DestroyWindow(wnd);
}

static FVideoDriver_Win32OpenGL iFVideoDriver_Win32OpenGL;

const char *VideoDriver_Win32OpenGL::Start(const StringList &param)
{
	if (BlitterFactory::GetCurrentBlitter()->GetScreenDepth() == 0) return "Only real blitters supported";

	Dimension old_res = _cur_resolution; // Save current screen resolution in case of errors, as MakeWindow invalidates it.

	LoadWGLExtensions();

	this->Initialize();
	this->MakeWindow(_fullscreen);

	/* Create and initialize OpenGL context. */
	const char *err = this->AllocateContext();
	if (err != nullptr) {
		this->Stop();
		_cur_resolution = old_res;
		return err;
	}

	this->ClientSizeChanged(this->width, this->height, true);
	/* We should have a valid screen buffer now. If not, something went wrong and we should abort. */
	if (_screen.dst_ptr == nullptr) {
		this->Stop();
		_cur_resolution = old_res;
		return "Can't get pointer to screen buffer";
	}

	MarkWholeScreenDirty();

	this->is_game_threaded = !GetDriverParamBool(param, "no_threads") && !GetDriverParamBool(param, "no_thread");

	return nullptr;
}

void VideoDriver_Win32OpenGL::Stop()
{
	this->DestroyContext();
	this->VideoDriver_Win32Base::Stop();
}

void VideoDriver_Win32OpenGL::DestroyContext()
{
	OpenGLBackend::Destroy();

	wglMakeCurrent(nullptr, nullptr);
	if (this->gl_rc != nullptr) {
		wglDeleteContext(this->gl_rc);
		this->gl_rc = nullptr;
	}
	if (this->dc != nullptr) {
		ReleaseDC(this->main_wnd, this->dc);
		this->dc = nullptr;
	}
}

void VideoDriver_Win32OpenGL::ToggleVsync(bool vsync)
{
	if (_wglSwapIntervalEXT != nullptr) {
		_wglSwapIntervalEXT(vsync);
	} else if (vsync) {
		DEBUG(driver, 0, "OpenGL: Vsync requested, but not supported by driver");
	}
}

const char *VideoDriver_Win32OpenGL::AllocateContext()
{
	this->dc = GetDC(this->main_wnd);

	const char *err = SelectPixelFormat(this->dc, this->fullscreen);
	if (err != nullptr) return err;

	HGLRC rc = nullptr;

	/* Create OpenGL device context. Try to get an 3.2+ context if possible. */
	if (_wglCreateContextAttribsARB != nullptr) {
		/* Try for OpenGL 4.5 first. */
		int attribs[] = {
			WGL_CONTEXT_MAJOR_VERSION_ARB, 4,
			WGL_CONTEXT_MINOR_VERSION_ARB, 5,
			WGL_CONTEXT_FLAGS_ARB, _debug_driver_level >= 8 ? WGL_CONTEXT_DEBUG_BIT_ARB : 0,
			_hasWGLARBCreateContextProfile ? WGL_CONTEXT_PROFILE_MASK_ARB : 0, WGL_CONTEXT_CORE_PROFILE_BIT_ARB, // Terminate list if WGL_ARB_create_context_profile isn't supported.
			0
		};
		rc = _wglCreateContextAttribsARB(this->dc, nullptr, attribs);

		if (rc == nullptr) {
			/* Try again for a 3.2 context. */
			attribs[1] = 3;
			attribs[3] = 2;
			rc = _wglCreateContextAttribsARB(this->dc, nullptr, attribs);
		}
	}

	if (rc == nullptr) {
		/* Old OpenGL or old driver, let's hope for the best. */
		rc = wglCreateContext(this->dc);
		if (rc == nullptr) return "Can't create OpenGL context";
	}
	if (!wglMakeCurrent(this->dc, rc)) return "Can't active GL context";

	this->ToggleVsync(_video_vsync);

	this->gl_rc = rc;
	return OpenGLBackend::Create(&GetOGLProcAddressCallback, this->GetScreenSize());
}

bool VideoDriver_Win32OpenGL::ToggleFullscreen(bool full_screen)
{
	if (_screen.dst_ptr != nullptr) this->ReleaseVideoPointer();
	this->DestroyContext();
	bool res = this->VideoDriver_Win32Base::ToggleFullscreen(full_screen);
	res &= this->AllocateContext() == nullptr;
	this->ClientSizeChanged(this->width, this->height, true);
	return res;
}

bool VideoDriver_Win32OpenGL::AfterBlitterChange()
{
	assert(BlitterFactory::GetCurrentBlitter()->GetScreenDepth() != 0);
	this->ClientSizeChanged(this->width, this->height, true);
	return true;
}

void VideoDriver_Win32OpenGL::PopulateSystemSprites()
{
	OpenGLBackend::Get()->PopulateCursorCache();
}

void VideoDriver_Win32OpenGL::ClearSystemSprites()
{
	OpenGLBackend::Get()->ClearCursorCache();
}

bool VideoDriver_Win32OpenGL::AllocateBackingStore(int w, int h, bool force)
{
	if (!force && w == _screen.width && h == _screen.height) return false;

	this->width = w = std::max(w, 64);
	this->height = h = std::max(h, 64);

	if (this->gl_rc == nullptr) return false;

	if (_screen.dst_ptr != nullptr) this->ReleaseVideoPointer();

	this->dirty_rect = {};
	bool res = OpenGLBackend::Get()->Resize(w, h, force);
	SwapBuffers(this->dc);
	_screen.dst_ptr = this->GetVideoPointer();

	return res;
}

void *VideoDriver_Win32OpenGL::GetVideoPointer()
{
	if (BlitterFactory::GetCurrentBlitter()->NeedsAnimationBuffer()) {
		this->anim_buffer = OpenGLBackend::Get()->GetAnimBuffer();
	}
	return OpenGLBackend::Get()->GetVideoBuffer();
}

void VideoDriver_Win32OpenGL::ReleaseVideoPointer()
{
	if (this->anim_buffer != nullptr) OpenGLBackend::Get()->ReleaseAnimBuffer(this->dirty_rect);
	OpenGLBackend::Get()->ReleaseVideoBuffer(this->dirty_rect);
	this->dirty_rect = {};
	_screen.dst_ptr = nullptr;
	this->anim_buffer = nullptr;
}

void VideoDriver_Win32OpenGL::Paint()
{
	PerformanceMeasurer framerate(PFE_VIDEO);

	if (_cur_palette.count_dirty != 0) {
		Blitter *blitter = BlitterFactory::GetCurrentBlitter();

		/* Always push a changed palette to OpenGL. */
		OpenGLBackend::Get()->UpdatePalette(_local_palette.palette, _local_palette.first_dirty, _local_palette.count_dirty);
		if (blitter->UsePaletteAnimation() == Blitter::PALETTE_ANIMATION_BLITTER) {
			blitter->PaletteAnimate(_local_palette);
		}

		_cur_palette.count_dirty = 0;
	}

	OpenGLBackend::Get()->Paint();
	OpenGLBackend::Get()->DrawMouseCursor();

	SwapBuffers(this->dc);
}

#endif /* WITH_OPENGL */