summaryrefslogtreecommitdiff
path: root/src/town_cmd.cpp
blob: ec7ca4e025ced54309be0e9a2f3dbd846da2c162 (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
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
/* $Id$ */

/** @file town_cmd.cpp */

#include "stdafx.h"
#include "openttd.h"
#include "tile_cmd.h"
#include "debug.h"
#include "road_map.h"
#include "road_internal.h" /* Cleaning up road bits */
#include "table/strings.h"
#include "table/sprites.h"
#include "landscape.h"
#include "town_map.h"
#include "tunnel_map.h"
#include "viewport_func.h"
#include "town.h"
#include "command_func.h"
#include "industry.h"
#include "station.h"
#include "player.h"
#include "news.h"
#include "saveload.h"
#include "gui.h"
#include "unmovable_map.h"
#include "water_map.h"
#include "variables.h"
#include "bridge.h"
#include "bridge_map.h"
#include "table/town_land.h"
#include "genworld.h"
#include "newgrf.h"
#include "newgrf_callbacks.h"
#include "newgrf_house.h"
#include "newgrf_commons.h"
#include "newgrf_townname.h"
#include "misc/autoptr.hpp"
#include "autoslope.h"
#include "waypoint.h"
#include "transparency.h"
#include "tunnelbridge_map.h"
#include "strings_func.h"
#include "window_func.h"
#include "string_func.h"


/* Initialize the town-pool */
DEFINE_OLD_POOL_GENERIC(Town, Town)

Town::Town(TileIndex tile)
{
	if (tile != 0) _total_towns++;
	this->xy = tile;
}

Town::~Town()
{
	DeleteName(this->townnametype);

	if (CleaningPool()) return;

	Industry *i;

	/* Delete town authority window
	 * and remove from list of sorted towns */
	DeleteWindowById(WC_TOWN_VIEW, this->index);
	_town_sort_dirty = true;
	_total_towns--;

	/* Delete all industries belonging to the town */
	FOR_ALL_INDUSTRIES(i) if (i->town == this) delete i;

	/* Go through all tiles and delete those belonging to the town */
	for (TileIndex tile = 0; tile < MapSize(); ++tile) {
		switch (GetTileType(tile)) {
			case MP_HOUSE:
				if (GetTownByTile(tile) == this) DoCommand(tile, 0, 0, DC_EXEC, CMD_LANDSCAPE_CLEAR);
				break;

			case MP_ROAD:
			case MP_TUNNELBRIDGE:
				if (IsTileOwner(tile, OWNER_TOWN) &&
						ClosestTownFromTile(tile, (uint)-1) == this)
					DoCommand(tile, 0, 0, DC_EXEC, CMD_LANDSCAPE_CLEAR);
				break;

			default:
				break;
		}
	}

	DeleteSubsidyWithTown(this->index);

	MarkWholeScreenDirty();

	this->xy = 0;
}

// Local
static int _grow_town_result;

/* Describe the possible states */
enum TownGrowthResult {
	GROWTH_SUCCEED         = -1,
	GROWTH_SEARCH_STOPPED  =  0
//	GROWTH_SEARCH_RUNNING >=  1
};

static bool BuildTownHouse(Town *t, TileIndex tile);
static void DoBuildTownHouse(Town *t, TileIndex tile);

static void TownDrawHouseLift(const TileInfo *ti)
{
	AddChildSpriteScreen(SPR_LIFT, PAL_NONE, 14, 60 - GetLiftPosition(ti->tile));
}

typedef void TownDrawTileProc(const TileInfo *ti);
static TownDrawTileProc * const _town_draw_tile_procs[1] = {
	TownDrawHouseLift
};

uint OriginalTileRandomiser(uint x, uint y)
{
	uint variant;
	variant  = x >> 4;
	variant ^= x >> 6;
	variant ^= y >> 4;
	variant -= y >> 6;
	variant &= 3;
	return variant;
}

/**
 * Return a random direction
 *
 * @return a random direction
 */
static inline DiagDirection RandomDiagDir()
{
	return (DiagDirection)(3 & Random());
}

/**
 * House Tile drawing handler.
 * Part of the tile loop process
 * @param ti TileInfo of the tile to draw
 */
static void DrawTile_Town(TileInfo *ti)
{
	const DrawBuildingsTileStruct *dcts;
	SpriteID image;
	SpriteID pal;
	HouseID house_id = GetHouseType(ti->tile);

	if (house_id >= NEW_HOUSE_OFFSET) {
		/* Houses don't necessarily need new graphics. If they don't have a
		 * spritegroup associated with them, then the sprite for the substitute
		 * house id is drawn instead. */
		if (GetHouseSpecs(house_id)->spritegroup != NULL) {
			DrawNewHouseTile(ti, house_id);
			return;
		} else {
			house_id = GetHouseSpecs(house_id)->substitute_id;
		}
	}

	/* Retrieve pointer to the draw town tile struct */
	dcts = &_town_draw_tile_data[house_id << 4 | OriginalTileRandomiser(ti->x, ti->y) << 2 | GetHouseBuildingStage(ti->tile)];

	if (ti->tileh != SLOPE_FLAT) DrawFoundation(ti, FOUNDATION_LEVELED);

	image = dcts->ground.sprite;
	pal   = dcts->ground.pal;
	DrawGroundSprite(image, pal);

	/* Add a house on top of the ground? */
	image = dcts->building.sprite;
	if (image != 0) {
		AddSortableSpriteToDraw(image, dcts->building.pal,
			ti->x + dcts->subtile_x,
			ti->y + dcts->subtile_y,
			dcts->width,
			dcts->height,
			dcts->dz,
			ti->z,
			IsTransparencySet(TO_HOUSES)
		);

		if (IsTransparencySet(TO_HOUSES)) return;
	}

	{
		int proc = dcts->draw_proc - 1;

		if (proc >= 0) _town_draw_tile_procs[proc](ti);
	}
}

static uint GetSlopeZ_Town(TileIndex tile, uint x, uint y)
{
	return GetTileMaxZ(tile);
}

static Foundation GetFoundation_Town(TileIndex tile, Slope tileh)
{
	return FlatteningFoundation(tileh);
}

/**
 * Animate a tile for a town
 * Only certain houses can be animated
 * The newhouses animation superseeds regular ones
 * @param tile TileIndex of the house to animate
 */
static void AnimateTile_Town(TileIndex tile)
{
	int pos, dest;

	if (GetHouseType(tile) >= NEW_HOUSE_OFFSET) {
		AnimateNewHouseTile(tile);
		return;
	}

	if (_tick_counter & 3) return;

	/* If the house is not one with a lift anymore, then stop this animating.
	 * Not exactly sure when this happens, but probably when a house changes.
	 * Before this was just a return...so it'd leak animated tiles..
	 * That bug seems to have been here since day 1?? */
	if (!(GetHouseSpecs(GetHouseType(tile))->building_flags & BUILDING_IS_ANIMATED)) {
		DeleteAnimatedTile(tile);
		return;
	}

	if (!LiftHasDestination(tile)) {
		int i;

		/*  Building has 6 floors, number 0 .. 6, where 1 is illegal.
		 *  This is due to the fact that the first floor is, in the graphics,
		 *  the height of 2 'normal' floors.
		 *  Furthermore, there are 6 lift positions from floor N (incl) to floor N + 1 (excl) */
		do {
			i = (Random() & 7) - 1;
		} while (i < 0 || i == 1 || i * 6 == GetLiftPosition(tile));

		SetLiftDestination(tile, i);
	}

	pos = GetLiftPosition(tile);
	dest = GetLiftDestination(tile) * 6;
	pos += (pos < dest) ? 1 : -1;
	SetLiftPosition(tile, pos);

	if (pos == dest) HaltLift(tile);

	MarkTileDirtyByTile(tile);
}

static void UpdateTownRadius(Town *t);

/**
 * Determines if a town is close to a tile
 * @param tile TileIndex of the tile to query
 * @param dist maximum distance to be accepted
 * @returns true if the tile correspond to the distance criteria
 */
static bool IsCloseToTown(TileIndex tile, uint dist)
{
	const Town* t;

	FOR_ALL_TOWNS(t) {
		if (DistanceManhattan(tile, t->xy) < dist) return true;
	}
	return false;
}

/**
 * Marks the town sign as needing a repaint.
 *
 * This function marks the area of the sign of a town as dirty for repaint.
 *
 * @param t Town requesting town sign for repaint
 * @ingroup dirty
 */
static void MarkTownSignDirty(Town *t)
{
	MarkAllViewportsDirty(
		t->sign.left - 6,
		t->sign.top - 3,
		t->sign.left + t->sign.width_1 * 4 + 12,
		t->sign.top + 45
	);
}

/**
 * Resize the sign(label) of the town after changes in
 * population (creation or growth or else)
 * @param t Town to update
 */
void UpdateTownVirtCoord(Town *t)
{
	Point pt;

	MarkTownSignDirty(t);
	pt = RemapCoords2(TileX(t->xy) * TILE_SIZE, TileY(t->xy) * TILE_SIZE);
	SetDParam(0, t->index);
	SetDParam(1, t->population);
	UpdateViewportSignPos(&t->sign, pt.x, pt.y - 24,
		_patches.population_in_label ? STR_TOWN_LABEL_POP : STR_TOWN_LABEL);
	MarkTownSignDirty(t);
}

/** Update the virtual coords needed to draw the town sign for all towns. */
void UpdateAllTownVirtCoords()
{
	Town *t;
	FOR_ALL_TOWNS(t) {
		UpdateTownVirtCoord(t);
	}
}

/**
 * Change the towns population
 * @param t Town which polulation has changed
 * @param mod polulation change (can be positive or negative)
 */
static void ChangePopulation(Town *t, int mod)
{
	t->population += mod;
	InvalidateWindow(WC_TOWN_VIEW, t->index);
	UpdateTownVirtCoord(t);

	if (_town_sort_order & 2) _town_sort_dirty = true;
}

/**
 * Determines the world population
 * Basically, count population of all towns, one by one
 * @return uint32 the calculated population of the world
 */
uint32 GetWorldPopulation()
{
	uint32 pop;
	const Town* t;

	pop = 0;
	FOR_ALL_TOWNS(t) pop += t->population;
	return pop;
}

/**
 * Helper function for house completion stages progression
 * @param tile TileIndex of the house (or parts of it) to "grow"
 */
static void MakeSingleHouseBigger(TileIndex tile)
{
	assert(IsTileType(tile, MP_HOUSE));

	/* means it is completed, get out. */
	if (LiftHasDestination(tile)) return;

	/* progress in construction stages */
	IncHouseConstructionTick(tile);
	if (GetHouseConstructionTick(tile) != 0) return;

	/* Check and/or  */
	if (HasBit(GetHouseSpecs(GetHouseType(tile))->callback_mask, CBM_HOUSE_CONSTRUCTION_STATE_CHANGE)) {
		uint16 callback_res = GetHouseCallback(CBID_HOUSE_CONSTRUCTION_STATE_CHANGE, 0, 0, GetHouseType(tile), GetTownByTile(tile), tile);
		if (callback_res != CALLBACK_FAILED) ChangeHouseAnimationFrame(tile, callback_res);
	}

	if (IsHouseCompleted(tile)) {
		/* Now that construction is complete, we can add the population of the
		 * building to the town. */
		ChangePopulation(GetTownByTile(tile), GetHouseSpecs(GetHouseType(tile))->population);
	}
	MarkTileDirtyByTile(tile);
}

/** Make the house advances in its construction stages until completion
 * @param tile TileIndex of house
 */
static void MakeTownHouseBigger(TileIndex tile)
{
	uint flags = GetHouseSpecs(GetHouseType(tile))->building_flags;
	if (flags & BUILDING_HAS_1_TILE)  MakeSingleHouseBigger(TILE_ADDXY(tile, 0, 0));
	if (flags & BUILDING_2_TILES_Y)   MakeSingleHouseBigger(TILE_ADDXY(tile, 0, 1));
	if (flags & BUILDING_2_TILES_X)   MakeSingleHouseBigger(TILE_ADDXY(tile, 1, 0));
	if (flags & BUILDING_HAS_4_TILES) MakeSingleHouseBigger(TILE_ADDXY(tile, 1, 1));
}

/**
 * Periodic tic handler for houses and town
 * @param tile been asked to do its stuff
 */
static void TileLoop_Town(TileIndex tile)
{
	Town *t;
	uint32 r;
	HouseID house_id = GetHouseType(tile);
	HouseSpec *hs = GetHouseSpecs(house_id);

	/* NewHouseTileLoop returns false if Callback 21 succeeded, i.e. the house
	 * doesn't exist any more, so don't continue here. */
	if (house_id >= NEW_HOUSE_OFFSET && !NewHouseTileLoop(tile)) return;

	if (!IsHouseCompleted(tile)) {
		/* Construction is not completed. See if we can go further in construction*/
		MakeTownHouseBigger(tile);
		return;
	}

	/* If the lift has a destination, it is already an animated tile. */
	if ((hs->building_flags & BUILDING_IS_ANIMATED) &&
			house_id < NEW_HOUSE_OFFSET &&
			!LiftHasDestination(tile) &&
			Chance16(1, 2))
		AddAnimatedTile(tile);

	t = GetTownByTile(tile);

	r = Random();

	if (HasBit(hs->callback_mask, CBM_HOUSE_PRODUCE_CARGO)) {
		for (uint i = 0; i < 256; i++) {
			uint16 callback = GetHouseCallback(CBID_HOUSE_PRODUCE_CARGO, i, r, house_id, t, tile);

			if (callback == CALLBACK_FAILED) break;
			if (callback == 0x20FF) break;

			CargoID cargo = GetCargoTranslation(GB(callback, 8, 7), hs->grffile);
			if (cargo == CT_INVALID) continue;

			uint amt = GB(callback, 0, 8);
			uint moved = MoveGoodsToStation(tile, 1, 1, cargo, amt);

			const CargoSpec *cs = GetCargo(cargo);
			switch (cs->town_effect) {
				case TE_PASSENGERS:
					t->new_max_pass += amt;
					t->new_act_pass += moved;
					break;

				case TE_MAIL:
					t->new_max_mail += amt;
					t->new_act_mail += moved;
					break;

				default:
					break;
			}
		}
	} else {
		if (GB(r, 0, 8) < hs->population) {
			uint amt = GB(r, 0, 8) / 8 + 1;
			uint moved;

			if (_economy.fluct <= 0) amt = (amt + 1) >> 1;
			t->new_max_pass += amt;
			moved = MoveGoodsToStation(tile, 1, 1, CT_PASSENGERS, amt);
			t->new_act_pass += moved;
		}

		if (GB(r, 8, 8) < hs->mail_generation) {
			uint amt = GB(r, 8, 8) / 8 + 1;
			uint moved;

			if (_economy.fluct <= 0) amt = (amt + 1) >> 1;
			t->new_max_mail += amt;
			moved = MoveGoodsToStation(tile, 1, 1, CT_MAIL, amt);
			t->new_act_mail += moved;
		}
	}

	_current_player = OWNER_TOWN;

	if (hs->building_flags & BUILDING_HAS_1_TILE &&
			HasBit(t->flags12, TOWN_IS_FUNDED) &&
			CanDeleteHouse(tile) &&
			max(_cur_year - GetHouseConstructionYear(tile), 0) >= hs->minimum_life &&
			--t->time_until_rebuild == 0) {
		t->time_until_rebuild = GB(r, 16, 8) + 192;

		ClearTownHouse(t, tile);

		/* Rebuild with another house? */
		if (GB(r, 24, 8) >= 12) DoBuildTownHouse(t, tile);
	}

	_current_player = OWNER_NONE;
}

/**
 * Unused handler
 * @param tile unused
 */
static void ClickTile_Town(TileIndex tile)
{
	/* not used */
}

static CommandCost ClearTile_Town(TileIndex tile, byte flags)
{
	int rating;
	CommandCost cost(EXPENSES_CONSTRUCTION);
	Town *t;
	HouseSpec *hs = GetHouseSpecs(GetHouseType(tile));

	if (flags&DC_AUTO && !(flags&DC_AI_BUILDING)) return_cmd_error(STR_2004_BUILDING_MUST_BE_DEMOLISHED);
	if (!CanDeleteHouse(tile)) return CMD_ERROR;

	cost.AddCost(_price.remove_house * hs->removal_cost >> 8);

	rating = hs->remove_rating_decrease;
	_cleared_town_rating += rating;
	_cleared_town = t = GetTownByTile(tile);

	if (IsValidPlayer(_current_player)) {
		if (rating > t->ratings[_current_player] && !(flags & DC_NO_TOWN_RATING) && !_cheats.magic_bulldozer.value) {
			SetDParam(0, t->index);
			return_cmd_error(STR_2009_LOCAL_AUTHORITY_REFUSES);
		}
	}

	ChangeTownRating(t, -rating, RATING_HOUSE_MINIMUM);
	if (flags & DC_EXEC) {
		ClearTownHouse(t, tile);
	}

	return cost;
}

static void GetAcceptedCargo_Town(TileIndex tile, AcceptedCargo ac)
{
	HouseSpec *hs = GetHouseSpecs(GetHouseType(tile));
	CargoID accepts[3];

	/* Set the initial accepted cargo types */
	for (uint8 i = 0; i < lengthof(accepts); i++) {
		accepts[i] = hs->accepts_cargo[i];
	}

	/* Check for custom accepted cargo types */
	if (HasBit(hs->callback_mask, CBM_HOUSE_ACCEPT_CARGO)) {
		uint16 callback = GetHouseCallback(CBID_HOUSE_ACCEPT_CARGO, 0, 0, GetHouseType(tile), GetTownByTile(tile), tile);
		if (callback != CALLBACK_FAILED) {
			/* Replace accepted cargo types with translated values from callback */
			accepts[0] = GetCargoTranslation(GB(callback,  0, 5), hs->grffile);
			accepts[1] = GetCargoTranslation(GB(callback,  5, 5), hs->grffile);
			accepts[2] = GetCargoTranslation(GB(callback, 10, 5), hs->grffile);
		}
	}

	/* Check for custom cargo acceptance */
	if (HasBit(hs->callback_mask, CBM_HOUSE_CARGO_ACCEPTANCE)) {
		uint16 callback = GetHouseCallback(CBID_HOUSE_CARGO_ACCEPTANCE, 0, 0, GetHouseType(tile), GetTownByTile(tile), tile);
		if (callback != CALLBACK_FAILED) {
			if (accepts[0] != CT_INVALID) ac[accepts[0]] = GB(callback, 0, 4);
			if (accepts[1] != CT_INVALID) ac[accepts[1]] = GB(callback, 4, 4);
			if (_opt.landscape != LT_TEMPERATE && HasBit(callback, 12)) {
				/* The 'S' bit indicates food instead of goods */
				ac[CT_FOOD] = GB(callback, 8, 4);
			} else {
				if (accepts[2] != CT_INVALID) ac[accepts[2]] = GB(callback, 8, 4);
			}
			return;
		}
	}

	/* No custom acceptance, so fill in with the default values */
	for (uint8 i = 0; i < lengthof(accepts); i++) {
		if (accepts[i] != CT_INVALID) ac[accepts[i]] = hs->cargo_acceptance[i];
	}
}

static void GetTileDesc_Town(TileIndex tile, TileDesc *td)
{
	td->str = GetHouseSpecs(GetHouseType(tile))->building_name;
	if (!IsHouseCompleted(tile)) {
		SetDParamX(td->dparam, 0, td->str);
		td->str = STR_2058_UNDER_CONSTRUCTION;
	}

	td->owner = OWNER_TOWN;
}

static uint32 GetTileTrackStatus_Town(TileIndex tile, TransportType mode, uint sub_mode)
{
	/* not used */
	return 0;
}

static void ChangeTileOwner_Town(TileIndex tile, PlayerID old_player, PlayerID new_player)
{
	/* not used */
}

static bool GrowTown(Town *t);

static void TownTickHandler(Town *t)
{
	if (HasBit(t->flags12, TOWN_IS_FUNDED)) {
		int i = t->grow_counter - 1;
		if (i < 0) {
			if (GrowTown(t)) {
				i = t->growth_rate;
			} else {
				i = 0;
			}
		}
		t->grow_counter = i;
	}

	UpdateTownRadius(t);
}

void OnTick_Town()
{
	if (_game_mode == GM_EDITOR) return;

	/* Make sure each town's tickhandler invocation frequency is about the
	 * same - TOWN_GROWTH_FREQUENCY - independent on the number of towns. */
	for (_cur_town_iter += GetMaxTownIndex() + 1;
	     _cur_town_iter >= TOWN_GROWTH_FREQUENCY;
	     _cur_town_iter -= TOWN_GROWTH_FREQUENCY) {
		uint32 i = _cur_town_ctr;

		if (++_cur_town_ctr > GetMaxTownIndex())
			_cur_town_ctr = 0;

		if (IsValidTownID(i)) TownTickHandler(GetTown(i));
	}
}

/**
 * Return the RoadBits of a tile
 *
 * @note There are many other functions doing things like that.
 * @note Needs to be checked for needlessness.
 * @param tile The tile we want to analyse
 * @return The roadbits of the given tile
 */
static RoadBits GetTownRoadBits(TileIndex tile)
{
	TrackBits b = GetAnyRoadTrackBits(tile, ROADTYPE_ROAD);
	RoadBits r = ROAD_NONE;

	if (b == TRACK_BIT_NONE) return r;
	if (b & TRACK_BIT_X)     r |= ROAD_X;
	if (b & TRACK_BIT_Y)     r |= ROAD_Y;
	if (b & TRACK_BIT_UPPER) r |= ROAD_NE | ROAD_NW;
	if (b & TRACK_BIT_LOWER) r |= ROAD_SE | ROAD_SW;
	if (b & TRACK_BIT_LEFT)  r |= ROAD_NW | ROAD_SW;
	if (b & TRACK_BIT_RIGHT) r |= ROAD_NE | ROAD_SE;
	return r;
}

/**
 * Check if a neighboring tile has a road
 *
 * @param tile curent tile
 * @param dir target direction
 * @param dist_multi distance multiplyer
 * @return true if one of the neighboring tiles at the
 *  given distance is a road tile else false
 */
static bool IsNeighborRoadTile(TileIndex tile, DiagDirection dir, uint dist_multi)
{
	static TileIndexDiff tid_lt[3]; // lookup table for the used diff values
	tid_lt[0] = TileOffsByDiagDir(ChangeDiagDir(dir, DIAGDIRDIFF_90RIGHT));
	tid_lt[1] = TileOffsByDiagDir(ChangeDiagDir(dir, DIAGDIRDIFF_90LEFT));
	tid_lt[2] = TileOffsByDiagDir(ReverseDiagDir(dir));

	/* We add 1 to the distance because we want to get 1 for
	 * the min distance multiplyer and not 0.
	 * Therefore we start at 4. The 4 is used because
	 * there are 4 tiles per distance step to check.
	 */
	dist_multi = (dist_multi + 1) * 4;
	for (uint pos = 4; pos < dist_multi; pos++) {
		TileIndexDiff cur = 0;
		/* For each even value of pos add the right TileIndexDiff
		 * for each uneven value the left TileIndexDiff
		 * for each with 2nd bit set (2,3,6,7,..) add the reversed TileIndexDiff
		 */
		cur += tid_lt[(pos & 1) ? 0 : 1];
		if (pos & 2) cur += tid_lt[2];

		cur = (uint)(pos / 4) * cur; // Multiply for the fitting distance
		if (GetTownRoadBits(TILE_ADD(tile, cur)) & DiagDirToRoadBits((pos & 2) ? dir : ReverseDiagDir(dir))) return true;
	}
	return false;
}

/**
 * Check if a Road is allowed on a given tile
 *
 * @param tile The target tile
 * @param dir The direction in which we want to extend the town
 * @return true if it is allowed else false
 */
static bool IsRoadAllowedHere(TileIndex tile, DiagDirection dir)
{
	if (TileX(tile) < 2 || TileY(tile) < 2 || MapMaxX() <= TileX(tile) || MapMaxY() <= TileY(tile)) return false;

	Slope cur_slope, desired_slope;

	/* If this assertion fails, it might be because the world contains
	 *  land at the edges. This is not ok. */
	TILE_ASSERT(tile);

	for (;;) {
		/* Check if there already is a road at this point? */
		if (GetTownRoadBits(tile) == ROAD_NONE) {
			/* No, try to build one in the direction.
			 * if that fails clear the land, and if that fails exit.
			 * This is to make sure that we can build a road here later. */
			if (CmdFailed(DoCommand(tile, ((dir == DIAGDIR_NW || dir == DIAGDIR_SE) ? ROAD_X : ROAD_Y), 0, DC_AUTO, CMD_BUILD_ROAD)) &&
					CmdFailed(DoCommand(tile, 0, 0, DC_AUTO, CMD_LANDSCAPE_CLEAR)))
				return false;
		}

		cur_slope = GetTileSlope(tile, NULL);
		if (cur_slope == SLOPE_FLAT) {
no_slope:
			/* Tile has no slope */
			switch (_patches.town_layout) {
				default: NOT_REACHED();

				case TL_ORIGINAL: /* Disallow the road if any neighboring tile has a road (distance: 1) */
					return !IsNeighborRoadTile(tile, dir, 1);

				case TL_BETTER_ROADS: /* Disallow the road if any neighboring tile has a road (distance: 1 and 2). */
					return !IsNeighborRoadTile(tile, dir, 2);
			}
		}

		/* If the tile is not a slope in the right direction, then
		 * maybe terraform some. */
		desired_slope = (dir == DIAGDIR_NW || dir == DIAGDIR_SE) ? SLOPE_NW : SLOPE_NE;
		if (desired_slope != cur_slope && ComplementSlope(desired_slope) != cur_slope) {
			if (Chance16(1, 8)) {
				CommandCost res = CMD_ERROR;
				if (!_generating_world && Chance16(1, 10)) {
					/* Note: Do not replace " ^ 0xF" with ComplementSlope(). The slope might be steep. */
					res = DoCommand(tile, Chance16(1, 16) ? cur_slope : cur_slope ^ 0xF, 0,
							DC_EXEC | DC_AUTO | DC_NO_WATER, CMD_TERRAFORM_LAND);
				}
				if (CmdFailed(res) && Chance16(1, 3)) {
					/* We can consider building on the slope, though. */
					goto no_slope;
				}
			}
			return false;
		}
		return true;
	}
}

static bool TerraformTownTile(TileIndex tile, int edges, int dir)
{
	CommandCost r;

	TILE_ASSERT(tile);

	r = DoCommand(tile, edges, dir, DC_AUTO | DC_NO_WATER, CMD_TERRAFORM_LAND);
	if (CmdFailed(r) || r.GetCost() >= 126 * 16) return false;
	DoCommand(tile, edges, dir, DC_AUTO | DC_NO_WATER | DC_EXEC, CMD_TERRAFORM_LAND);
	return true;
}

static void LevelTownLand(TileIndex tile)
{
	Slope tileh;

	TILE_ASSERT(tile);

	/* Don't terraform if land is plain or if there's a house there. */
	if (IsTileType(tile, MP_HOUSE)) return;
	tileh = GetTileSlope(tile, NULL);
	if (tileh == SLOPE_FLAT) return;

	/* First try up, then down */
	if (!TerraformTownTile(tile, ~tileh & 0xF, 1)) {
		TerraformTownTile(tile, tileh & 0xF, 0);
	}
}

/**
 * Generate the RoadBits of a grid tile
 *
 * @param t current town
 * @param tile tile in reference to the town
 * @param dir The direction to which we are growing ATM
 * @return the RoadBit of the current tile regarding
 *  the selected town layout
 */
static RoadBits GetTownRoadGridElement(Town* t, TileIndex tile, DiagDirection dir)
{
	/* align the grid to the downtown */
	TileIndexDiffC grid_pos = TileIndexToTileIndexDiffC(t->xy, tile); // Vector from downtown to the tile
	RoadBits rcmd = ROAD_NONE;

	switch (_patches.town_layout) {
		default: NOT_REACHED();

		case TL_2X2_GRID:
			if ((grid_pos.x % 3) == 0) rcmd |= ROAD_Y;
			if ((grid_pos.y % 3) == 0) rcmd |= ROAD_X;
			break;

		case TL_3X3_GRID:
			if ((grid_pos.x % 4) == 0) rcmd |= ROAD_Y;
			if ((grid_pos.y % 4) == 0) rcmd |= ROAD_X;
			break;
	}

	/* Optimise only X-junctions */
	if (rcmd != ROAD_ALL) return rcmd;

	RoadBits rb_template;

	switch (GetTileSlope(tile, NULL)) {
		default:       rb_template = ROAD_ALL; break;
		case SLOPE_W:  rb_template = ROAD_NW | ROAD_SW; break;
		case SLOPE_SW: rb_template = ROAD_Y  | ROAD_SW; break;
		case SLOPE_S:  rb_template = ROAD_SW | ROAD_SE; break;
		case SLOPE_SE: rb_template = ROAD_X  | ROAD_SE; break;
		case SLOPE_E:  rb_template = ROAD_SE | ROAD_NE; break;
		case SLOPE_NE: rb_template = ROAD_Y  | ROAD_NE; break;
		case SLOPE_N:  rb_template = ROAD_NE | ROAD_NW; break;
		case SLOPE_NW: rb_template = ROAD_X  | ROAD_NW; break;
		case SLOPE_STEEP_W:
		case SLOPE_STEEP_S:
		case SLOPE_STEEP_E:
		case SLOPE_STEEP_N:
			rb_template = ROAD_NONE;
			break;
	}

	/* Stop if the template is compatible to the growth dir */
	if (DiagDirToRoadBits(ReverseDiagDir(dir)) & rb_template) return rb_template;
	/* If not generate a straight road in the direction of the growth */
	return DiagDirToRoadBits(dir) | DiagDirToRoadBits(ReverseDiagDir(dir));
}

/**
 * Grows the town with an extra house.
 *  Check if there are enough neighbor house tiles
 *  next to the current tile. If there are enough
 *  add another house.
 *
 * @param t The current town
 * @param tile The target tile for the extra house
 * @return true if an extra house has been added
 */
static bool GrowTownWithExtraHouse(Town *t, TileIndex tile)
{
	/* We can't look further than that. */
	if (TileX(tile) < 2 || TileY(tile) < 2 || MapMaxX() <= TileX(tile) || MapMaxY() <= TileY(tile)) return false;

	uint counter = 0; // counts the house neighbor tiles

	/* Check the tiles E,N,W and S of the current tile for houses */
	for (DiagDirection dir = DIAGDIR_BEGIN; dir < DIAGDIR_END; dir++) {

		if (IsTileType(TileAddByDiagDir(tile, dir), MP_HOUSE)) counter++;

		/* If there are enough neighbors stop here */
		if (counter >= 3) {
			if (BuildTownHouse(t, tile)) {
				_grow_town_result = GROWTH_SUCCEED;
				return true;
			}
			return false;
		}
	}
	return false;
}

/**
 * Grows the town with a road piece.
 *
 * @param t The current town
 * @param tile The current tile
 * @param rcmd The RoadBits we want to build on the tile
 * @return true if the RoadBits have been added else false
 */
static bool GrowTownWithRoad(const Town *t, TileIndex tile, RoadBits rcmd)
{
	if (CmdSucceeded(DoCommand(tile, rcmd, t->index, DC_EXEC | DC_AUTO | DC_NO_WATER, CMD_BUILD_ROAD))) {
		_grow_town_result = GROWTH_SUCCEED;
		return true;
	}
	return false;
}

/**
 * Grows the town with a bridge.
 *  At first we check if a bridge is reasonable.
 *  If so we check if we are able to build it.
 *
 * @param t The current town
 * @param tile The current tile
 * @param bridge_dir The valid direction in which to grow a bridge
 * @return true if a bridge has been build else false
 */
static bool GrowTownWithBridge(const Town *t, TileIndex tile, DiagDirection bridge_dir)
{
	assert(bridge_dir < DIAGDIR_END);

	const Slope slope = GetTileSlope(tile, NULL);
	if (slope == SLOPE_FLAT) return false; // no slope, no bridge

	/* Make sure the direction is compatible with the slope.
	 * If any of the following bits match, the slope is forbidden for
	 *  that diagdir. This means 5 non-steep slopes, and 3 steep-slopes
	 *  per diagdir.
	 * 0 -> 0b1100
	 * 1 -> 0b0110
	 * 2 -> 0b0011
	 * 3 -> 0b1001
	 * 0xCC is 0b11001100, so we just shift it right with
	 * the direction to get the forbidden slope mask. */
	if (HASBITS(slope & 0x0F, 0xCC >> bridge_dir)) return false;

	/* Assure that the bridge is connectable to the start side */
	if (!(GetTownRoadBits(TileAddByDiagDir(tile, ReverseDiagDir(bridge_dir))) & DiagDirToRoadBits(bridge_dir))) return false;

	/* We are in the right direction */
	uint8 bridge_length = 0;     // This value stores the length of the possible bridge
	TileIndex bridge_tile = tile; // Used to store the other waterside

	int delta = TileOffsByDiagDir(bridge_dir);

	do {
		if (bridge_length++ >= 11) {
			/* Max 11 tile long bridges */
			return false;
		}
		bridge_tile += delta;
	} while (TileX(bridge_tile) != 0 && TileY(bridge_tile) != 0 && IsWaterTile(bridge_tile) && TileX(bridge_tile) != 0);

	/* no water tiles in between? */
	if (bridge_length == 1) return false;

	for (uint8 times = 0; times <= 22; times++) {
		byte bridge_type = RandomRange(MAX_BRIDGES - 1);

		/* Can we actually build the bridge? */
		if (CmdSucceeded(DoCommand(tile, bridge_tile, bridge_type | ((0x80 | ROADTYPES_ROAD) << 8), DC_AUTO, CMD_BUILD_BRIDGE))) {
			DoCommand(tile, bridge_tile, bridge_type | ((0x80 | ROADTYPES_ROAD) << 8), DC_EXEC | DC_AUTO, CMD_BUILD_BRIDGE);
			_grow_town_result = GROWTH_SUCCEED;
			return true;
		}
	}
	/* Quit if it selecting an appropiate bridge type fails a large number of times. */
	return false;
}

/**
 * Grows the given town.
 * There are at the moment 3 possible way's for
 * the town expansion:
 *  @li Generate a random tile and check if there is a road allowed
 *  @li TL_ORIGINAL
 *  @li TL_BETTER_ROADS
 *  @li Check if the town geometry allows a road and which one
 *  @li TL_2X2_GRID
 *  @li TL_3X3_GRID
 *  @li Forbid roads, only build houses
 *  @li TL_NO_ROADS
 *
 * @param tile_ptr The current tile
 * @param cur_rb The current tiles RoadBits
 * @param target_dir The target road dir
 * @param t1 The current town
 */
static void GrowTownInTile(TileIndex *tile_ptr, RoadBits cur_rb, DiagDirection target_dir, Town *t1)
{
	RoadBits rcmd = ROAD_NONE;  // RoadBits for the road construction command
	TileIndex tile = *tile_ptr; // The main tile on which we base our growth

	TILE_ASSERT(tile);

	if (cur_rb == ROAD_NONE) {
		/* Tile has no road. First reset the status counter
		 * to say that this is the last iteration. */
		_grow_town_result = GROWTH_SEARCH_STOPPED;

		/* Remove hills etc */
		LevelTownLand(tile);

		/* Is a road allowed here? */
		switch (_patches.town_layout) {
			default: NOT_REACHED();

			case TL_NO_ROADS: /* Disallow Roads */
				return;

			case TL_3X3_GRID:
			case TL_2X2_GRID:
				rcmd = GetTownRoadGridElement(t1, tile, target_dir);
				if (rcmd == ROAD_NONE) return;
				break;

			case TL_BETTER_ROADS:
			case TL_ORIGINAL:
				if (!IsRoadAllowedHere(tile, target_dir)) return;

				DiagDirection source_dir = ReverseDiagDir(target_dir);

				if (Chance16(1, 4)) {
					/* Randomize a new target dir */
					do target_dir = RandomDiagDir(); while (target_dir == source_dir);
				}

				if (!IsRoadAllowedHere(TileAddByDiagDir(tile, target_dir), target_dir)) {
					/* A road is not allowed to continue the randomized road,
					 *  return if the road we're trying to build is curved. */
					if (target_dir != ReverseDiagDir(source_dir)) return;

					/* Return if neither side of the new road is a house */
					if (!IsTileType(TileAddByDiagDir(tile, ChangeDiagDir(target_dir, DIAGDIRDIFF_90RIGHT)), MP_HOUSE) &&
							!IsTileType(TileAddByDiagDir(tile, ChangeDiagDir(target_dir, DIAGDIRDIFF_90LEFT)), MP_HOUSE)) {
						return;
					}

					/* That means that the road is only allowed if there is a house
					 *  at any side of the new road. */
				}

				rcmd = DiagDirToRoadBits(target_dir) | DiagDirToRoadBits(source_dir);
				break;
		}

	} else if (target_dir < DIAGDIR_END && !(cur_rb & DiagDirToRoadBits(ReverseDiagDir(target_dir)))) {
		/* Continue building on a partial road.
		 * Should be allways OK, so we only generate
		 * the fitting RoadBits */
		_grow_town_result = GROWTH_SEARCH_STOPPED;

		switch (_patches.town_layout) {
			default: NOT_REACHED();

			case TL_NO_ROADS: /* Disallow Roads */
				return;

			case TL_3X3_GRID:
			case TL_2X2_GRID:
			 	rcmd = GetTownRoadGridElement(t1, tile, target_dir);
				break;

			case TL_BETTER_ROADS:
			case TL_ORIGINAL:
				rcmd = DiagDirToRoadBits(ReverseDiagDir(target_dir));
				break;
		}
	} else {
		bool allow_house = false; // Value which decides if we want to construct a house

		/* Reached a tunnel/bridge? Then continue at the other side of it. */
		if (IsTileType(tile, MP_TUNNELBRIDGE)) {
			if (GetTunnelBridgeTransportType(tile) == TRANSPORT_ROAD) {
				*tile_ptr = GetOtherTunnelBridgeEnd(tile);
			}
			return;
		}

		/* Possibly extend the road in a direction.
		 * Randomize a direction and if it has a road, bail out. */
		target_dir = RandomDiagDir();
		if (cur_rb & DiagDirToRoadBits(target_dir)) return;

		/* This is the tile we will reach if we extend to this direction. */
		TileIndex house_tile = TileAddByDiagDir(tile, target_dir); // position of a possible house

		/* Don't walk into water. */
		if (IsWaterTile(house_tile)) return;

		switch (_patches.town_layout) {
			default: NOT_REACHED();

			case TL_NO_ROADS:
				allow_house = true;
				break;

			case TL_3X3_GRID: /* Use 2x2 grid afterwards! */
				GrowTownWithExtraHouse(t1, TileAddByDiagDir(house_tile, target_dir));
				/* FALL THROUGH */

			case TL_2X2_GRID:
				rcmd = GetTownRoadGridElement(t1, house_tile, target_dir);
				allow_house = (rcmd == ROAD_NONE);
				break;

			case TL_BETTER_ROADS: /* Use original afterwards! */
				GrowTownWithExtraHouse(t1, TileAddByDiagDir(house_tile, target_dir));
				/* FALL THROUGH */

			case TL_ORIGINAL:
				 /* Allow a house at the edge. 60% chance or
				  * always ok if no road allowed. */
				rcmd = DiagDirToRoadBits(target_dir);
				allow_house = (!IsRoadAllowedHere(house_tile, target_dir) || Chance16(6, 10));
				break;
		}

		if (allow_house) {
			/* Build a house, but not if there already is a house there. */
			if (!IsTileType(house_tile, MP_HOUSE)) {
				/* Level the land if possible */
				if (Chance16(1, 6)) LevelTownLand(house_tile);

				/* And build a house.
				 * Set result to -1 if we managed to build it. */
				if (BuildTownHouse(t1, house_tile)) {
					_grow_town_result = GROWTH_SUCCEED;
				}
			}
			return;
		}

		_grow_town_result = GROWTH_SEARCH_STOPPED;
	}

	/* Return if a water tile */
	if (IsWaterTile(tile)) return;

	/* Make the roads look nicer */
	rcmd = CleanUpRoadBits(tile, rcmd);
	if (rcmd == ROAD_NONE) return;

	/* Only use the target direction for bridges to ensure they're connected.
	 * The target_dir is as computed previously according to town layout, so
	 * it will match it perfectly. */
	if (GrowTownWithBridge(t1, tile, target_dir)) return;

	GrowTownWithRoad(t1, tile, rcmd);
}

/** Returns "growth" if a house was built, or no if the build failed.
 * @param t town to inquiry
 * @param tile to inquiry
 * @return something other than zero(0)if town expansion was possible
 */
static int GrowTownAtRoad(Town *t, TileIndex tile)
{
	/* Special case.
	 * @see GrowTownInTile Check the else if
	 */
	DiagDirection target_dir = DIAGDIR_END; // The direction in which we want to extend the town

	TILE_ASSERT(tile);

	/* Number of times to search.
	 * Better roads, 2X2 and 3X3 grid grow quite fast so we give
	 * them a little handicap. */
	switch (_patches.town_layout) {
		case TL_BETTER_ROADS:
			_grow_town_result = 10 + t->num_houses * 2 / 9;
			break;

		case TL_3X3_GRID:
		case TL_2X2_GRID:
			_grow_town_result = 10 + t->num_houses * 1 / 9;
			break;

		default:
			_grow_town_result = 10 + t->num_houses * 4 / 9;
			break;
	}

	do {
		RoadBits cur_rb = GetTownRoadBits(tile); // The RoadBits of the current tile

		/* Try to grow the town from this point */
		GrowTownInTile(&tile, cur_rb, target_dir, t);

		/* Exclude the source position from the bitmask
		 * and return if no more road blocks available */
		cur_rb &= ~DiagDirToRoadBits(ReverseDiagDir(target_dir));
		if (cur_rb == ROAD_NONE)
			return _grow_town_result;

		/* Select a random bit from the blockmask, walk a step
		 * and continue the search from there. */
		do target_dir = RandomDiagDir(); while (!(cur_rb & DiagDirToRoadBits(target_dir)));
		tile = TileAddByDiagDir(tile, target_dir);

		if (IsTileType(tile, MP_ROAD)) {
			/* Don't allow building over roads of other cities */
			if (IsTileOwner(tile, OWNER_TOWN) && GetTownByTile(tile) != t) {
				_grow_town_result = GROWTH_SUCCEED;
			} else if (_game_mode == GM_EDITOR) {
				/* If we are in the SE, and this road-piece has no town owner yet, it just found an
				 * owner :) (happy happy happy road now) */
				SetTileOwner(tile, OWNER_TOWN);
				SetTownIndex(tile, t->index);
			}
		}

		/* Max number of times is checked. */
	} while (--_grow_town_result >= 0);

	return (_grow_town_result == -2);
}

/**
 * Generate a random road block.
 * The probability of a straight road
 * is somewhat higher than a curved.
 *
 * @return A RoadBits value with 2 bits set
 */
static RoadBits GenRandomRoadBits()
{
	uint32 r = Random();
	uint a = GB(r, 0, 2);
	uint b = GB(r, 8, 2);
	if (a == b) b ^= 2;
	return (RoadBits)((ROAD_NW << a) + (ROAD_NW << b));
}

/** Grow the town
 * @Return true if a house was built, or no if the build failed. */
static bool GrowTown(Town *t)
{

	/* Let the town be a ghost town
	 * The player wanted it in such a way. Thus there he has it. ;)
	 * Never reached in editor mode. */
	if (_patches.town_layout == TL_NO_ROADS && _generating_world) {
		return false;
	}

	static const TileIndexDiffC _town_coord_mod[] = {
		{-1,  0},
		{ 1,  1},
		{ 1, -1},
		{-1, -1},
		{-1,  0},
		{ 0,  2},
		{ 2,  0},
		{ 0, -2},
		{-1, -1},
		{-2,  2},
		{ 2,  2},
		{ 2, -2},
		{ 0,  0}
	};
	const TileIndexDiffC *ptr;

	/* Current player is a town */
	PlayerID old_player = _current_player;
	_current_player = OWNER_TOWN;

	TileIndex tile = t->xy; // The tile we are working with ATM

	/* Find a road that we can base the construction on. */
	for (ptr = _town_coord_mod; ptr != endof(_town_coord_mod); ++ptr) {
		if (GetTownRoadBits(tile) != ROAD_NONE) {
			int r = GrowTownAtRoad(t, tile);
			_current_player = old_player;
			return r != 0;
		}
		tile = TILE_ADD(tile, ToTileIndexDiff(*ptr));
	}

	/* No road available, try to build a random road block by
	 * clearing some land and then building a road there. */
	tile = t->xy;
	for (ptr = _town_coord_mod; ptr != endof(_town_coord_mod); ++ptr) {
		/* Only work with plain land that not already has a house */
		if (!IsTileType(tile, MP_HOUSE) && GetTileSlope(tile, NULL) == SLOPE_FLAT) {
			if (CmdSucceeded(DoCommand(tile, 0, 0, DC_AUTO | DC_NO_WATER, CMD_LANDSCAPE_CLEAR))) {
				DoCommand(tile, GenRandomRoadBits(), t->index, DC_EXEC | DC_AUTO, CMD_BUILD_ROAD);
				_current_player = old_player;
				return true;
			}
		}
		tile = TILE_ADD(tile, ToTileIndexDiff(*ptr));
	}

	_current_player = old_player;
	return false;
}

static void UpdateTownRadius(Town *t)
{
	static const uint16 _town_radius_data[23][5] = {
		{  4,  0,  0,  0,  0}, // 0
		{ 16,  0,  0,  0,  0},
		{ 25,  0,  0,  0,  0},
		{ 36,  0,  0,  0,  0},
		{ 49,  0,  4,  0,  0},
		{ 64,  0,  4,  0,  0}, // 20
		{ 64,  0,  9,  0,  1},
		{ 64,  0,  9,  0,  4},
		{ 64,  0, 16,  0,  4},
		{ 81,  0, 16,  0,  4},
		{ 81,  0, 16,  0,  4}, // 40
		{ 81,  0, 25,  0,  9},
		{ 81, 36, 25,  0,  9},
		{ 81, 36, 25, 16,  9},
		{ 81, 49,  0, 25,  9},
		{ 81, 64,  0, 25,  9}, // 60
		{ 81, 64,  0, 36,  9},
		{ 81, 64,  0, 36, 16},
		{100, 81,  0, 49, 16},
		{100, 81,  0, 49, 25},
		{121, 81,  0, 49, 25}, // 80
		{121, 81,  0, 49, 25},
		{121, 81,  0, 49, 36}, // 88
	};

	if (t->num_houses < 92) {
		memcpy(t->radius, _town_radius_data[t->num_houses / 4], sizeof(t->radius));
	} else {
		int mass = t->num_houses / 8;
		/* At least very roughly extrapolate. Empirical numbers dancing between
		 * overwhelming by cottages and skyscrapers outskirts. */
		t->radius[0] = mass * mass;
		/* Actually we are proportional to sqrt() but that's right because
		 * we are covering an area. */
		t->radius[1] = mass * 7;
		t->radius[2] = 0;
		t->radius[3] = mass * 4;
		t->radius[4] = mass * 3;
		//debug("%d (->%d): %d %d %d %d\n", t->num_houses, mass, t->radius[0], t->radius[1], t->radius[3], t->radius[4]);
	}
}

static bool CreateTownName(uint32 *townnameparts)
{
	extern int _nb_orig_names;
	Town *t2;
	char buf1[64];
	char buf2[64];
	uint32 r;
	/* Do not set too low tries, since when we run out of names, we loop
	 * for #tries only one time anyway - then we stop generating more
	 * towns. Do not show it too high neither, since looping through all
	 * the other towns may take considerable amount of time (10000 is
	 * too much). */
	int tries = 1000;
	bool grf = (_opt.town_name >= _nb_orig_names);
	uint32 grfid = grf ? GetGRFTownNameId(_opt.town_name - _nb_orig_names) : 0;
	uint16 townnametype = grf ? GetGRFTownNameType(_opt.town_name - _nb_orig_names) : SPECSTR_TOWNNAME_START + _opt.town_name;

	assert(townnameparts);

	for (;;) {
restart:
		r = Random();

		SetDParam(0, r);
		if (grf && grfid != 0) {
			GRFTownNameGenerate(buf1, grfid, townnametype, r, lastof(buf1));
		} else {
			GetString(buf1, townnametype, lastof(buf1));
		}

		/* Check size and width */
		if (strlen(buf1) >= 31 || GetStringBoundingBox(buf1).width > 130) continue;

		FOR_ALL_TOWNS(t2) {
			/* We can't just compare the numbers since
			 * several numbers may map to a single name. */
			SetDParam(0, t2->index);
			GetString(buf2, STR_TOWN, lastof(buf2));
			if (strcmp(buf1, buf2) == 0) {
				if (tries-- < 0) return false;
				goto restart;
			}
		}
		*townnameparts = r;
		return true;
	}
}

void UpdateTownMaxPass(Town *t)
{
	t->max_pass = t->population >> 3;
	t->max_mail = t->population >> 4;
}

/**
 * Does the actual town creation.
 *
 * @param t The town
 * @param tile Where to put it
 * @param townnameparts The town name
 * @param size_mode How the size should be determined
 * @param size Parameter for size determination
 */
static void DoCreateTown(Town *t, TileIndex tile, uint32 townnameparts, TownSizeMode size_mode, uint size)
{
	extern int _nb_orig_names;
	int x, i;

	t->xy = tile;
	t->num_houses = 0;
	t->time_until_rebuild = 10;
	UpdateTownRadius(t);
	t->flags12 = 0;
	t->population = 0;
	t->grow_counter = 0;
	t->growth_rate = 250;
	t->new_max_pass = 0;
	t->new_max_mail = 0;
	t->new_act_pass = 0;
	t->new_act_mail = 0;
	t->max_pass = 0;
	t->max_mail = 0;
	t->act_pass = 0;
	t->act_mail = 0;

	t->pct_pass_transported = 0;
	t->pct_mail_transported = 0;
	t->fund_buildings_months = 0;
	t->new_act_food = 0;
	t->new_act_water = 0;
	t->act_food = 0;
	t->act_water = 0;

	for (i = 0; i != MAX_PLAYERS; i++)
		t->ratings[i] = 500;

	t->have_ratings = 0;
	t->exclusivity = INVALID_PLAYER;
	t->exclusive_counter = 0;
	t->statues = 0;

	if (_opt.town_name < _nb_orig_names) {
		/* Original town name */
		t->townnamegrfid = 0;
		t->townnametype = SPECSTR_TOWNNAME_START + _opt.town_name;
	} else {
		/* Newgrf town name */
		t->townnamegrfid = GetGRFTownNameId(_opt.town_name  - _nb_orig_names);
		t->townnametype  = GetGRFTownNameType(_opt.town_name - _nb_orig_names);
	}
	t->townnameparts = townnameparts;

	UpdateTownVirtCoord(t);
	_town_sort_dirty = true;

	/* Random town size. */
	x = (Random() & 0xF) + 8;

	switch (size_mode) {
		default: NOT_REACHED();

		case TSM_RANDOM:
			t->larger_town = false;
			break;

		case TSM_FIXED:
			x = size * 16 + 3;
			t->larger_town = false;
			break;

		case TSM_CITY:
			x *= _patches.initial_city_size;
			t->larger_town = true;
			break;
	}

	t->num_houses += x;
	UpdateTownRadius(t);

	i = x * 4;
	do {
		GrowTown(t);
	} while (--i);

	t->num_houses -= x;
	UpdateTownRadius(t);
	UpdateTownMaxPass(t);
}

/** Create a new town.
 * This obviously only works in the scenario editor. Function not removed
 * as it might be possible in the future to fund your own town :)
 * @param tile coordinates where town is built
 * @param flags type of operation
 * @param p1 size of the town (0 = small, 1 = medium, 2 = large)
 * @param p2 size mode (@see TownSizeMode)
 */
CommandCost CmdBuildTown(TileIndex tile, uint32 flags, uint32 p1, uint32 p2)
{
	uint32 townnameparts;

	/* Only in the scenario editor */
	if (_game_mode != GM_EDITOR) return CMD_ERROR;
	if (p2 > TSM_CITY) return CMD_ERROR;

	/* Check if too close to the edge of map */
	if (DistanceFromEdge(tile) < 12)
		return_cmd_error(STR_0237_TOO_CLOSE_TO_EDGE_OF_MAP);

	/* Can only build on clear flat areas, possibly with trees. */
	if ((!IsTileType(tile, MP_CLEAR) && !IsTileType(tile, MP_TREES)) || GetTileSlope(tile, NULL) != SLOPE_FLAT) {
		return_cmd_error(STR_0239_SITE_UNSUITABLE);
	}

	/* Check distance to all other towns. */
	if (IsCloseToTown(tile, 20))
		return_cmd_error(STR_0238_TOO_CLOSE_TO_ANOTHER_TOWN);

	/* Get a unique name for the town. */
	if (!CreateTownName(&townnameparts))
		return_cmd_error(STR_023A_TOO_MANY_TOWNS);

	/* Allocate town struct */
	Town *t = new Town(tile);
	if (t == NULL) return_cmd_error(STR_023A_TOO_MANY_TOWNS);
	AutoPtrT<Town> t_auto_delete = t;

	/* Create the town */
	if (flags & DC_EXEC) {
		_generating_world = true;
		DoCreateTown(t, tile, townnameparts, (TownSizeMode)p2, p1);
		_generating_world = false;
		t_auto_delete.Detach();
	}
	return CommandCost();
}

Town *CreateRandomTown(uint attempts, TownSizeMode mode, uint size)
{
	TileIndex tile;
	Town *t;
	uint32 townnameparts;

	do {
		/* Generate a tile index not too close from the edge */
		tile = RandomTile();
		if (DistanceFromEdge(tile) < 20) continue;

		/* Make sure the tile is plain */
		if (!IsTileType(tile, MP_CLEAR) || GetTileSlope(tile, NULL) != SLOPE_FLAT) continue;

		/* Check not too close to a town */
		if (IsCloseToTown(tile, 20)) continue;

		/* Get a unique name for the town. */
		if (!CreateTownName(&townnameparts)) break;

		/* Allocate a town struct */
		t = new Town(tile);
		if (t == NULL) break;

		DoCreateTown(t, tile, townnameparts, mode, size);
		return t;
	} while (--attempts);
	return NULL;
}

static const byte _num_initial_towns[4] = {5, 11, 23, 46};

bool GenerateTowns()
{
	uint num = 0;
	uint n = ScaleByMapSize(_num_initial_towns[_opt.diff.number_towns] + (Random() & 7));
	uint num_cities = _patches.larger_towns == 0 ? 0 : n / _patches.larger_towns;

	SetGeneratingWorldProgress(GWP_TOWN, n);

	do {
		IncreaseGeneratingWorldProgress(GWP_TOWN);
		/* try 20 times to create a random-sized town for the first loop. */
		TownSizeMode mode = num_cities > 0 ? TSM_CITY : TSM_RANDOM;
		if (CreateRandomTown(20, mode, _patches.initial_city_size) != NULL) num++;
		if (num_cities > 0) num_cities--;
	} while (--n);

	/* give it a last try, but now more aggressive */
	if (num == 0 && CreateRandomTown(10000, TSM_RANDOM, 0) == NULL) {
		if (GetNumTowns() == 0) {
			/* XXX - can we handle that more gracefully? */
			if (_game_mode != GM_EDITOR) error("Could not generate any town");

			return false;
		}
	}

	return true;
}

static bool CheckBuildHouseMode(TileIndex tile, Slope tileh, int mode)
{
	int b;
	Slope slope;

	static const byte _masks[8] = {
		0xC,0x3,0x9,0x6,
		0x3,0xC,0x6,0x9,
	};

	slope = GetTileSlope(tile, NULL);
	if (IsSteepSlope(slope)) return false;

	if (MayHaveBridgeAbove(tile) && IsBridgeAbove(tile)) return false;

	b = 0;
	if ((slope != SLOPE_FLAT && ~slope & _masks[mode])) b = ~b;
	if ((tileh != SLOPE_FLAT && ~tileh & _masks[mode+4])) b = ~b;
	if (b)
		return false;

	return CmdSucceeded(DoCommand(tile, 0, 0, DC_EXEC | DC_AUTO | DC_NO_WATER, CMD_LANDSCAPE_CLEAR));
}


uint GetTownRadiusGroup(const Town* t, TileIndex tile)
{
	uint dist = DistanceSquare(tile, t->xy);
	uint smallest;
	uint i;

	if (t->fund_buildings_months && dist <= 25) return 4;

	smallest = 0;
	for (i = 0; i != lengthof(t->radius); i++) {
		if (dist < t->radius[i]) smallest = i;
	}

	return smallest;
}

static bool CheckFree2x2Area(TileIndex tile)
{
	int i;

	static const TileIndexDiffC _tile_add[] = {
		{0    , 0    },
		{0 - 0, 1 - 0},
		{1 - 0, 0 - 1},
		{1 - 1, 1 - 0}
	};

	for (i = 0; i != 4; i++) {
		tile += ToTileIndexDiff(_tile_add[i]);

		if (GetTileSlope(tile, NULL) != SLOPE_FLAT) return false;

		if (MayHaveBridgeAbove(tile) && IsBridgeAbove(tile)) return false;

		if (CmdFailed(DoCommand(tile, 0, 0, DC_EXEC | DC_AUTO | DC_NO_WATER | DC_FORCETEST, CMD_LANDSCAPE_CLEAR)))
			return false;
	}

	return true;
}

static void DoBuildTownHouse(Town *t, TileIndex tile)
{
	int i;
	uint bitmask;
	HouseID house;
	Slope slope;
	uint z;
	uint oneof = 0;
	HouseSpec *hs;

	/* Above snow? */
	slope = GetTileSlope(tile, &z);

	/* Get the town zone type */
	{
		uint rad = GetTownRadiusGroup(t, tile);

		int land = _opt.landscape;
		if (land == LT_ARCTIC && z >= _opt.snow_line) land = -1;

		bitmask = (1 << rad) + (1 << (land + 12));
	}

	/* bits 0-4 are used
	 * bits 11-15 are used
	 * bits 5-10 are not used. */
	{
		HouseID houses[HOUSE_MAX];
		int num = 0;
		uint cumulative_probs[HOUSE_MAX];
		uint probability_max = 0;

		/* Generate a list of all possible houses that can be built. */
		for (i = 0; i < HOUSE_MAX; i++) {
			hs = GetHouseSpecs(i);
			if ((~hs->building_availability & bitmask) == 0 && hs->enabled) {
				if (_loaded_newgrf_features.has_newhouses) {
					probability_max += hs->probability;
					cumulative_probs[num] = probability_max;
				}
				houses[num++] = (HouseID)i;
			}
		}

		for (;;) {
			if (_loaded_newgrf_features.has_newhouses) {
				uint r = RandomRange(probability_max);
				for (i = 0; i < num; i++) if (cumulative_probs[i] >= r) break;

				house = houses[i];
			} else {
				house = houses[RandomRange(num)];
			}

			hs = GetHouseSpecs(house);

			if (_loaded_newgrf_features.has_newhouses) {
				if (hs->override != 0) {
					house = hs->override;
					hs = GetHouseSpecs(house);
				}

				if ((hs->extra_flags & BUILDING_IS_HISTORICAL) && !_generating_world) continue;

				if (HasBit(hs->callback_mask, CBM_HOUSE_ALLOW_CONSTRUCTION)) {
					uint16 callback_res = GetHouseCallback(CBID_HOUSE_ALLOW_CONSTRUCTION, 0, 0, house, t, tile);
					if (callback_res != CALLBACK_FAILED && callback_res == 0) continue;
				}
			}

			if (_cur_year < hs->min_date || _cur_year > hs->max_date) continue;

			/* Special houses that there can be only one of. */
			if (hs->building_flags & BUILDING_IS_CHURCH) {
				SetBit(oneof, TOWN_HAS_CHURCH);
			} else if (hs->building_flags & BUILDING_IS_STADIUM) {
				SetBit(oneof, TOWN_HAS_STADIUM);
			} else {
				oneof = 0;
			}

			if (HASBITS(t->flags12 , oneof)) continue;

			/* Make sure there is no slope? */
			if (hs->building_flags & TILE_NOT_SLOPED && slope != SLOPE_FLAT) continue;

			if (hs->building_flags & TILE_SIZE_2x2) {
				if (CheckFree2x2Area(tile) ||
						CheckFree2x2Area(tile += TileDiffXY(-1,  0)) ||
						CheckFree2x2Area(tile += TileDiffXY( 0, -1)) ||
						CheckFree2x2Area(tile += TileDiffXY( 1,  0))) {
					break;
				}
				tile += TileDiffXY(0, 1);
			} else if (hs->building_flags & TILE_SIZE_2x1) {
				if (CheckBuildHouseMode(tile + TileDiffXY(1, 0), slope, 0)) break;

				if (CheckBuildHouseMode(tile + TileDiffXY(-1, 0), slope, 1)) {
					tile += TileDiffXY(-1, 0);
					break;
				}
			} else if (hs->building_flags & TILE_SIZE_1x2) {
				if (CheckBuildHouseMode(tile + TileDiffXY(0, 1), slope, 2)) break;

				if (CheckBuildHouseMode(tile + TileDiffXY(0, -1), slope, 3)) {
					tile += TileDiffXY(0, -1);
					break;
				}
			} else {
				break;
			}
		}
	}

	t->num_houses++;
	IncreaseBuildingCount(t, house);

	/* Special houses that there can be only one of. */
	t->flags12 |= oneof;

	{
		byte construction_counter = 0, construction_stage = 0;

		if (_generating_world) {
			uint32 r = Random();

			construction_stage = TOWN_HOUSE_COMPLETED;
			if (Chance16(1, 7)) construction_stage = GB(r, 0, 2);

			if (construction_stage == TOWN_HOUSE_COMPLETED) {
				ChangePopulation(t, hs->population);
			} else {
				construction_counter = GB(r, 2, 2);
			}
		}
		MakeTownHouse(tile, t->index, construction_counter, construction_stage, house, Random());
	}
}

static bool BuildTownHouse(Town *t, TileIndex tile)
{
	CommandCost r;

	if (IsSteepSlope(GetTileSlope(tile, NULL))) return false;
	if (MayHaveBridgeAbove(tile) && IsBridgeAbove(tile)) return false;

	r = DoCommand(tile, 0, 0, DC_EXEC | DC_AUTO | DC_NO_WATER, CMD_LANDSCAPE_CLEAR);
	if (CmdFailed(r)) return false;

	DoBuildTownHouse(t, tile);
	return true;
}


static void DoClearTownHouseHelper(TileIndex tile)
{
	assert(IsTileType(tile, MP_HOUSE));
	DoClearSquare(tile);
	DeleteAnimatedTile(tile);
}

void ClearTownHouse(Town *t, TileIndex tile)
{
	HouseID house = GetHouseType(tile);
	uint eflags;
	HouseSpec *hs;

	assert(IsTileType(tile, MP_HOUSE));

	/* need to align the tile to point to the upper left corner of the house */
	if (house >= 3) { // house id 0,1,2 MUST be single tile houses, or this code breaks.
		if (GetHouseSpecs(house-1)->building_flags & TILE_SIZE_2x1) {
			house--;
			tile += TileDiffXY(-1, 0);
		} else if (GetHouseSpecs(house-1)->building_flags & BUILDING_2_TILES_Y) {
			house--;
			tile += TileDiffXY(0, -1);
		} else if (GetHouseSpecs(house-2)->building_flags & BUILDING_HAS_4_TILES) {
			house-=2;
			tile += TileDiffXY(-1, 0);
		} else if (GetHouseSpecs(house-3)->building_flags & BUILDING_HAS_4_TILES) {
			house-=3;
			tile += TileDiffXY(-1, -1);
		}
	}

	hs = GetHouseSpecs(house);

	/* Remove population from the town if the house is finished. */
	if (IsHouseCompleted(tile)) {
		ChangePopulation(t, -hs->population);
	}

	t->num_houses--;
	DecreaseBuildingCount(t, house);

	/* Clear flags for houses that only may exist once/town. */
	if (hs->building_flags & BUILDING_IS_CHURCH) {
		ClrBit(t->flags12, TOWN_HAS_CHURCH);
	} else if (hs->building_flags & BUILDING_IS_STADIUM) {
		ClrBit(t->flags12, TOWN_HAS_STADIUM);
	}

	/* Do the actual clearing of tiles */
	eflags = hs->building_flags;
	DoClearTownHouseHelper(tile);
	if (eflags & BUILDING_2_TILES_X)   DoClearTownHouseHelper(tile + TileDiffXY(1, 0));
	if (eflags & BUILDING_2_TILES_Y)   DoClearTownHouseHelper(tile + TileDiffXY(0, 1));
	if (eflags & BUILDING_HAS_4_TILES) DoClearTownHouseHelper(tile + TileDiffXY(1, 1));
}

static bool IsUniqueTownName(const char *name)
{
	const Town *t;
	char buf[512];

	FOR_ALL_TOWNS(t) {
		SetDParam(0, t->index);
		GetString(buf, STR_TOWN, lastof(buf));
		if (strcmp(buf, name) == 0) return false;
	}

	return true;
}

/** Rename a town (server-only).
 * @param tile unused
 * @param flags type of operation
 * @param p1 town ID to rename
 * @param p2 unused
 */
CommandCost CmdRenameTown(TileIndex tile, uint32 flags, uint32 p1, uint32 p2)
{
	StringID str;
	Town *t;

	if (!IsValidTownID(p1) || StrEmpty(_cmd_text)) return CMD_ERROR;

	t = GetTown(p1);

	if (!IsUniqueTownName(_cmd_text)) return_cmd_error(STR_NAME_MUST_BE_UNIQUE);

	str = AllocateName(_cmd_text, 4);
	if (str == 0) return CMD_ERROR;

	if (flags & DC_EXEC) {
		DeleteName(t->townnametype);
		t->townnametype = str;
		t->townnamegrfid = 0;

		UpdateTownVirtCoord(t);
		_town_sort_dirty = true;
		UpdateAllStationVirtCoord();
		UpdateAllWaypointSigns();
		MarkWholeScreenDirty();
	} else {
		DeleteName(str);
	}
	return CommandCost();
}

/** Called from GUI */
void ExpandTown(Town *t)
{
	int amount, n;

	_generating_world = true;

	/* The more houses, the faster we grow */
	amount = RandomRange(t->num_houses / 10) + 3;
	t->num_houses += amount;
	UpdateTownRadius(t);

	n = amount * 10;
	do GrowTown(t); while (--n);

	t->num_houses -= amount;
	UpdateTownRadius(t);

	UpdateTownMaxPass(t);
	_generating_world = false;
}

extern const byte _town_action_costs[8] = {
	2, 4, 9, 35, 48, 53, 117, 175
};

static void TownActionAdvertiseSmall(Town* t)
{
	ModifyStationRatingAround(t->xy, _current_player, 0x40, 10);
}

static void TownActionAdvertiseMedium(Town* t)
{
	ModifyStationRatingAround(t->xy, _current_player, 0x70, 15);
}

static void TownActionAdvertiseLarge(Town* t)
{
	ModifyStationRatingAround(t->xy, _current_player, 0xA0, 20);
}

static void TownActionRoadRebuild(Town* t)
{
	t->road_build_months = 6;

	SetDParam(0, t->index);
	SetDParam(1, _current_player);

	AddNewsItem(STR_2055_TRAFFIC_CHAOS_IN_ROAD_REBUILDING,
		NEWS_FLAGS(NM_NORMAL, NF_TILE, NT_GENERAL, 0), t->xy, 0);
}

static bool DoBuildStatueOfCompany(TileIndex tile, TownID town_id)
{
	PlayerID old;
	CommandCost r;

	/* Statues can be build on slopes, just like houses. Only the steep slopes is a no go. */
	if (IsSteepSlope(GetTileSlope(tile, NULL))) return false;

	if (!IsTileType(tile, MP_HOUSE) &&
			!IsTileType(tile, MP_CLEAR) &&
			!IsTileType(tile, MP_TREES)) {
		return false;
	}

	old = _current_player;
	_current_player = OWNER_NONE;
	r = DoCommand(tile, 0, 0, DC_EXEC, CMD_LANDSCAPE_CLEAR);
	_current_player = old;

	if (CmdFailed(r)) return false;

	MakeStatue(tile, _current_player, town_id);
	MarkTileDirtyByTile(tile);

	return true;
}

/**
 * Search callback function for TownActionBuildStatue
 * @param tile on which to perform the search
 * @param town_id The town_id for which we want a statue
 * @return the result of the test
 */
static bool SearchTileForStatue(TileIndex tile, uint32 town_id)
{
	return DoBuildStatueOfCompany(tile, town_id);
}

/**
 * Perform a 9x9 tiles circular search from the center of the town
 * in order to find a free tile to place a statue
 * @param t town to search in
 */
static void TownActionBuildStatue(Town* t)
{
	TileIndex tile = t->xy;

	if (CircularTileSearch(tile, 9, SearchTileForStatue, t->index))
		SetBit(t->statues, _current_player); // Once found and built, "inform" the Town
}

static void TownActionFundBuildings(Town* t)
{
	/* Build next tick */
	t->grow_counter = 1;
	/* If we were not already growing */
	SetBit(t->flags12, TOWN_IS_FUNDED);
	/* And grow for 3 months */
	t->fund_buildings_months = 3;
}

static void TownActionBuyRights(Town* t)
{
	/* Check if it's allowed to by the rights */
	if (!_patches.exclusive_rights) return;

	t->exclusive_counter = 12;
	t->exclusivity = _current_player;

	ModifyStationRatingAround(t->xy, _current_player, 130, 17);
}

static void TownActionBribe(Town* t)
{
	if (!RandomRange(15)) {
		Station *st;

		/* set as unwanted for 6 months */
		t->unwanted[_current_player] = 6;

		/* set all close by station ratings to 0 */
		FOR_ALL_STATIONS(st) {
			if (st->town == t && st->owner == _current_player) {
				for (CargoID i = 0; i < NUM_CARGO; i++) st->goods[i].rating = 0;
			}
		}

		/* only show errormessage to the executing player. All errors are handled command.c
		 * but this is special, because it can only 'fail' on a DC_EXEC */
		if (IsLocalPlayer()) ShowErrorMessage(STR_BRIBE_FAILED_2, STR_BRIBE_FAILED, 0, 0);

		/* decrease by a lot!
		 * ChangeTownRating is only for stuff in demolishing. Bribe failure should
		 * be independent of any cheat settings
		 */
		if (t->ratings[_current_player] > RATING_BRIBE_DOWN_TO) {
			t->ratings[_current_player] = RATING_BRIBE_DOWN_TO;
		}
	} else {
		ChangeTownRating(t, RATING_BRIBE_UP_STEP, RATING_BRIBE_MAXIMUM);
	}
}

typedef void TownActionProc(Town* t);
static TownActionProc * const _town_action_proc[] = {
	TownActionAdvertiseSmall,
	TownActionAdvertiseMedium,
	TownActionAdvertiseLarge,
	TownActionRoadRebuild,
	TownActionBuildStatue,
	TownActionFundBuildings,
	TownActionBuyRights,
	TownActionBribe
};

extern uint GetMaskOfTownActions(int *nump, PlayerID pid, const Town *t);

/** Do a town action.
 * This performs an action such as advertising, building a statue, funding buildings,
 * but also bribing the town-council
 * @param tile unused
 * @param flags type of operation
 * @param p1 town to do the action at
 * @param p2 action to perform, @see _town_action_proc for the list of available actions
 */
CommandCost CmdDoTownAction(TileIndex tile, uint32 flags, uint32 p1, uint32 p2)
{
	Town *t;

	if (!IsValidTownID(p1) || p2 > lengthof(_town_action_proc)) return CMD_ERROR;

	t = GetTown(p1);

	if (!HasBit(GetMaskOfTownActions(NULL, _current_player, t), p2)) return CMD_ERROR;

	CommandCost cost(EXPENSES_OTHER, (_price.build_industry >> 8) * _town_action_costs[p2]);

	if (flags & DC_EXEC) {
		_town_action_proc[p2](t);
		InvalidateWindow(WC_TOWN_AUTHORITY, p1);
	}

	return cost;
}

static void UpdateTownGrowRate(Town *t)
{
	int n;
	Station *st;
	uint16 m;
	Player *p;

	/* Reset player ratings if they're low */
	FOR_ALL_PLAYERS(p) {
		if (p->is_active && t->ratings[p->index] <= 200) {
			t->ratings[p->index] += 5;
		}
	}

	n = 0;
	FOR_ALL_STATIONS(st) {
		if (DistanceSquare(st->xy, t->xy) <= t->radius[0]) {
			if (st->time_since_load <= 20 || st->time_since_unload <= 20) {
				n++;
				if (IsValidPlayer(st->owner) && t->ratings[st->owner] <= 1000-12)
					t->ratings[st->owner] += 12;
			} else {
				if (IsValidPlayer(st->owner) && t->ratings[st->owner] >= -1000+15)
					t->ratings[st->owner] -= 15;
			}
		}
	}

	ClrBit(t->flags12, TOWN_IS_FUNDED);
	if (_patches.town_growth_rate == 0 && t->fund_buildings_months == 0) return;

	/** Towns are processed every TOWN_GROWTH_FREQUENCY ticks, and this is the
	 * number of times towns are processed before a new building is built. */
	static const uint16 _grow_count_values[2][6] = {
		{ 120, 120, 120, 100,  80,  60 }, // Fund new buildings has been activated
		{ 320, 420, 300, 220, 160, 100 }  // Normal values
	};

	if (t->fund_buildings_months != 0) {
		m = _grow_count_values[0][min(n, 5)];
		t->fund_buildings_months--;
	} else {
		m = _grow_count_values[1][min(n, 5)];
		if (n == 0 && !Chance16(1, 12)) return;
	}

	if (_opt.landscape == LT_ARCTIC) {
		if (TilePixelHeight(t->xy) >= GetSnowLine() && t->act_food == 0 && t->population > 90)
			return;
	} else if (_opt.landscape == LT_TROPIC) {
		if (GetTropicZone(t->xy) == TROPICZONE_DESERT && (t->act_food==0 || t->act_water==0) && t->population > 60)
			return;
	}

	/* Use the normal growth rate values if new buildings have been funded in
	 * this town and the growth rate is set to none. */
	uint growth_multiplier = _patches.town_growth_rate != 0 ? _patches.town_growth_rate - 1 : 1;

	m >>= growth_multiplier;
	if (t->larger_town) m /= 2;

	t->growth_rate = m / (t->num_houses / 50 + 1);
	if (m <= t->grow_counter)
		t->grow_counter = m;

	SetBit(t->flags12, TOWN_IS_FUNDED);
}

static void UpdateTownAmounts(Town *t)
{
	/* Using +1 here to prevent overflow and division by zero */
	t->pct_pass_transported = t->new_act_pass * 256 / (t->new_max_pass + 1);

	t->max_pass = t->new_max_pass; t->new_max_pass = 0;
	t->act_pass = t->new_act_pass; t->new_act_pass = 0;
	t->act_food = t->new_act_food; t->new_act_food = 0;
	t->act_water = t->new_act_water; t->new_act_water = 0;

	/* Using +1 here to prevent overflow and division by zero */
	t->pct_mail_transported = t->new_act_mail * 256 / (t->new_max_mail + 1);
	t->max_mail = t->new_max_mail; t->new_max_mail = 0;
	t->act_mail = t->new_act_mail; t->new_act_mail = 0;

	InvalidateWindow(WC_TOWN_VIEW, t->index);
}

static void UpdateTownUnwanted(Town *t)
{
	const Player* p;

	FOR_ALL_PLAYERS(p) {
		if (t->unwanted[p->index] > 0) t->unwanted[p->index]--;
	}
}

bool CheckIfAuthorityAllows(TileIndex tile)
{
	Town *t;

	if (!IsValidPlayer(_current_player)) return true;

	t = ClosestTownFromTile(tile, _patches.dist_local_authority);
	if (t == NULL) return true;

	if (t->ratings[_current_player] > -200) return true;

	_error_message = STR_2009_LOCAL_AUTHORITY_REFUSES;
	SetDParam(0, t->index);

	return false;
}


Town* CalcClosestTownFromTile(TileIndex tile, uint threshold)
{
	Town *t;
	uint dist, best = threshold;
	Town *best_town = NULL;

	FOR_ALL_TOWNS(t) {
		dist = DistanceManhattan(tile, t->xy);
		if (dist < best) {
			best = dist;
			best_town = t;
		}
	}

	return best_town;
}


Town *ClosestTownFromTile(TileIndex tile, uint threshold)
{
	if (IsTileType(tile, MP_HOUSE) || (
				IsTileType(tile, MP_ROAD) &&
				GetRoadOwner(tile, ROADTYPE_ROAD) == OWNER_TOWN
			)) {
		return GetTownByTile(tile);
	} else {
		return CalcClosestTownFromTile(tile, threshold);
	}
}

static bool _town_rating_test = false;

void SetTownRatingTestMode(bool mode)
{
	static int ref_count = 0;
	if (mode) {
		if (ref_count == 0) {
			Town *t;
			FOR_ALL_TOWNS(t) t->test_rating = t->ratings[_current_player];
		}
		ref_count++;
	} else {
		assert(ref_count > 0);
		ref_count--;
	}
	_town_rating_test = !(ref_count == 0);
}

void ChangeTownRating(Town *t, int add, int max)
{
	int rating;

	/* if magic_bulldozer cheat is active, town doesn't penaltize for removing stuff */
	if (t == NULL ||
			!IsValidPlayer(_current_player) ||
			(_cheats.magic_bulldozer.value && add < 0)) {
		return;
	}

	SetBit(t->have_ratings, _current_player);

	rating = _town_rating_test ? t->test_rating : t->ratings[_current_player];

	if (add < 0) {
		if (rating > max) {
			rating += add;
			if (rating < max) rating = max;
		}
	} else {
		if (rating < max) {
			rating += add;
			if (rating > max) rating = max;
		}
	}
	if (_town_rating_test) {
		t->test_rating = rating;
	} else {
		t->ratings[_current_player] = rating;
	}
}

/* penalty for removing town-owned stuff */
static const int _default_rating_settings [3][3] = {
	/* ROAD_REMOVE, TUNNELBRIDGE_REMOVE, INDUSTRY_REMOVE */
	{  0, 128, 384}, // Permissive
	{ 48, 192, 480}, // Neutral
	{ 96, 384, 768}, // Hostile
};

bool CheckforTownRating(uint32 flags, Town *t, byte type)
{
	int modemod;

	/* if magic_bulldozer cheat is active, town doesn't restrict your destructive actions */
	if (t == NULL || !IsValidPlayer(_current_player) || _cheats.magic_bulldozer.value)
		return true;

	/* check if you're allowed to remove the street/bridge/tunnel/industry
	 * owned by a town no removal if rating is lower than ... depends now on
	 * difficulty setting. Minimum town rating selected by difficulty level
	 */
	modemod = _default_rating_settings[_opt.diff.town_council_tolerance][type];

	if ((_town_rating_test ? t->test_rating : t->ratings[_current_player]) < 16 + modemod && !(flags & DC_NO_TOWN_RATING)) {
		SetDParam(0, t->index);
		_error_message = STR_2009_LOCAL_AUTHORITY_REFUSES;
		return false;
	}

	return true;
}

void TownsMonthlyLoop()
{
	Town *t;

	FOR_ALL_TOWNS(t) {
		if (t->road_build_months != 0) t->road_build_months--;

		if (t->exclusive_counter != 0)
			if (--t->exclusive_counter == 0) t->exclusivity = INVALID_PLAYER;

		UpdateTownGrowRate(t);
		UpdateTownAmounts(t);
		UpdateTownUnwanted(t);
	}
}

void InitializeTowns()
{
	Subsidy *s;

	/* Clean the town pool and create 1 block in it */
	_Town_pool.CleanPool();
	_Town_pool.AddBlockToPool();

	memset(_subsidies, 0, sizeof(_subsidies));
	for (s=_subsidies; s != endof(_subsidies); s++)
		s->cargo_type = CT_INVALID;

	_cur_town_ctr = 0;
	_cur_town_iter = 0;
	_total_towns = 0;
	_town_sort_dirty = true;
}

static CommandCost TerraformTile_Town(TileIndex tile, uint32 flags, uint z_new, Slope tileh_new)
{
	if (AutoslopeEnabled()) {
		HouseID house = GetHouseType(tile);
		HouseSpec *hs = GetHouseSpecs(house);

		/* Here we differ from TTDP by checking TILE_NOT_SLOPED */
		if (((hs->building_flags & TILE_NOT_SLOPED) == 0) && !IsSteepSlope(tileh_new) &&
			(GetTileMaxZ(tile) == z_new + GetSlopeMaxZ(tileh_new))) return CommandCost(EXPENSES_CONSTRUCTION, _price.terraform);
	}

	return DoCommand(tile, 0, 0, flags, CMD_LANDSCAPE_CLEAR);
}

extern const TileTypeProcs _tile_type_town_procs = {
	DrawTile_Town,           /* draw_tile_proc */
	GetSlopeZ_Town,          /* get_slope_z_proc */
	ClearTile_Town,          /* clear_tile_proc */
	GetAcceptedCargo_Town,   /* get_accepted_cargo_proc */
	GetTileDesc_Town,        /* get_tile_desc_proc */
	GetTileTrackStatus_Town, /* get_tile_track_status_proc */
	ClickTile_Town,          /* click_tile_proc */
	AnimateTile_Town,        /* animate_tile_proc */
	TileLoop_Town,           /* tile_loop_clear */
	ChangeTileOwner_Town,    /* change_tile_owner_clear */
	NULL,                    /* get_produced_cargo_proc */
	NULL,                    /* vehicle_enter_tile_proc */
	GetFoundation_Town,      /* get_foundation_proc */
	TerraformTile_Town,      /* terraform_tile_proc */
};


/** Save and load of towns. */
static const SaveLoad _town_desc[] = {
	SLE_CONDVAR(Town, xy,                    SLE_FILE_U16 | SLE_VAR_U32, 0, 5),
	SLE_CONDVAR(Town, xy,                    SLE_UINT32,                 6, SL_MAX_VERSION),

	SLE_CONDVAR(Town, population,            SLE_FILE_U16 | SLE_VAR_U32, 0, 2),
	SLE_CONDVAR(Town, population,            SLE_UINT32,                 3, SL_MAX_VERSION),


	    SLE_VAR(Town, num_houses,            SLE_UINT16),
	SLE_CONDVAR(Town, townnamegrfid,         SLE_UINT32, 66, SL_MAX_VERSION),
	    SLE_VAR(Town, townnametype,          SLE_UINT16),
	    SLE_VAR(Town, townnameparts,         SLE_UINT32),

	    SLE_VAR(Town, flags12,               SLE_UINT8),
	    SLE_VAR(Town, statues,               SLE_UINT8),

	/* sort_index_obsolete was stored here in savegame format 0 - 1 */
	SLE_CONDNULL(1, 0, 1),

	    SLE_VAR(Town, have_ratings,          SLE_UINT8),
	    SLE_ARR(Town, ratings,               SLE_INT16, 8),
	/* failed bribe attempts are stored since savegame format 4 */
	SLE_CONDARR(Town, unwanted,              SLE_INT8, 8, 4,SL_MAX_VERSION),

	SLE_CONDVAR(Town, max_pass,              SLE_FILE_U16 | SLE_VAR_U32, 0, 8),
	SLE_CONDVAR(Town, max_mail,              SLE_FILE_U16 | SLE_VAR_U32, 0, 8),
	SLE_CONDVAR(Town, new_max_pass,          SLE_FILE_U16 | SLE_VAR_U32, 0, 8),
	SLE_CONDVAR(Town, new_max_mail,          SLE_FILE_U16 | SLE_VAR_U32, 0, 8),
	SLE_CONDVAR(Town, act_pass,              SLE_FILE_U16 | SLE_VAR_U32, 0, 8),
	SLE_CONDVAR(Town, act_mail,              SLE_FILE_U16 | SLE_VAR_U32, 0, 8),
	SLE_CONDVAR(Town, new_act_pass,          SLE_FILE_U16 | SLE_VAR_U32, 0, 8),
	SLE_CONDVAR(Town, new_act_mail,          SLE_FILE_U16 | SLE_VAR_U32, 0, 8),

	SLE_CONDVAR(Town, max_pass,              SLE_UINT32,                 9, SL_MAX_VERSION),
	SLE_CONDVAR(Town, max_mail,              SLE_UINT32,                 9, SL_MAX_VERSION),
	SLE_CONDVAR(Town, new_max_pass,          SLE_UINT32,                 9, SL_MAX_VERSION),
	SLE_CONDVAR(Town, new_max_mail,          SLE_UINT32,                 9, SL_MAX_VERSION),
	SLE_CONDVAR(Town, act_pass,              SLE_UINT32,                 9, SL_MAX_VERSION),
	SLE_CONDVAR(Town, act_mail,              SLE_UINT32,                 9, SL_MAX_VERSION),
	SLE_CONDVAR(Town, new_act_pass,          SLE_UINT32,                 9, SL_MAX_VERSION),
	SLE_CONDVAR(Town, new_act_mail,          SLE_UINT32,                 9, SL_MAX_VERSION),

	    SLE_VAR(Town, pct_pass_transported,  SLE_UINT8),
	    SLE_VAR(Town, pct_mail_transported,  SLE_UINT8),

	    SLE_VAR(Town, act_food,              SLE_UINT16),
	    SLE_VAR(Town, act_water,             SLE_UINT16),
	    SLE_VAR(Town, new_act_food,          SLE_UINT16),
	    SLE_VAR(Town, new_act_water,         SLE_UINT16),

	SLE_CONDVAR(Town, time_until_rebuild,    SLE_UINT8,                  0, 53),
	SLE_CONDVAR(Town, grow_counter,          SLE_UINT8,                  0, 53),
	SLE_CONDVAR(Town, growth_rate,           SLE_UINT8,                  0, 53),

	SLE_CONDVAR(Town, time_until_rebuild,    SLE_UINT16,                 54, SL_MAX_VERSION),
	SLE_CONDVAR(Town, grow_counter,          SLE_UINT16,                 54, SL_MAX_VERSION),
	SLE_CONDVAR(Town, growth_rate,           SLE_INT16,                  54, SL_MAX_VERSION),

	    SLE_VAR(Town, fund_buildings_months, SLE_UINT8),
	    SLE_VAR(Town, road_build_months,     SLE_UINT8),

	    SLE_VAR(Town, exclusivity,           SLE_UINT8),
	    SLE_VAR(Town, exclusive_counter,     SLE_UINT8),

	SLE_CONDVAR(Town, larger_town,           SLE_BOOL,                  56, SL_MAX_VERSION),

	/* reserve extra space in savegame here. (currently 30 bytes) */
	SLE_CONDNULL(30, 2, SL_MAX_VERSION),

	SLE_END()
};

/* Save and load the mapping between the house id on the map, and the grf file
 * it came from. */
static const SaveLoad _house_id_mapping_desc[] = {
	SLE_VAR(EntityIDMapping, grfid,         SLE_UINT32),
	SLE_VAR(EntityIDMapping, entity_id,     SLE_UINT8),
	SLE_VAR(EntityIDMapping, substitute_id, SLE_UINT8),
	SLE_END()
};

static void Save_HOUSEIDS()
{
	uint j = _house_mngr.GetMaxMapping();

	for (uint i = 0; i < j; i++) {
		SlSetArrayIndex(i);
		SlObject(&_house_mngr.mapping_ID[i], _house_id_mapping_desc);
	}
}

static void Load_HOUSEIDS()
{
	int index;

	_house_mngr.ResetMapping();
	uint max_id = _house_mngr.GetMaxMapping();

	while ((index = SlIterateArray()) != -1) {
		if ((uint)index >= max_id) break;
		SlObject(&_house_mngr.mapping_ID[index], _house_id_mapping_desc);
	}
}

static void Save_TOWN()
{
	Town *t;

	FOR_ALL_TOWNS(t) {
		SlSetArrayIndex(t->index);
		SlObject(t, _town_desc);
	}
}

static void Load_TOWN()
{
	int index;

	_total_towns = 0;

	while ((index = SlIterateArray()) != -1) {
		Town *t = new (index) Town();
		SlObject(t, _town_desc);

		_total_towns++;
	}

	/* This is to ensure all pointers are within the limits of
	 *  the size of the TownPool */
	if (_cur_town_ctr > GetMaxTownIndex())
		_cur_town_ctr = 0;
}

void AfterLoadTown()
{
	Town *t;
	FOR_ALL_TOWNS(t) {
		UpdateTownRadius(t);
	}
	_town_sort_dirty = true;
}

extern const ChunkHandler _town_chunk_handlers[] = {
	{ 'HIDS', Save_HOUSEIDS, Load_HOUSEIDS, CH_ARRAY },
	{ 'CITY', Save_TOWN,     Load_TOWN,     CH_ARRAY | CH_LAST},
};

void ResetHouses()
{
	memset(&_house_specs, 0, sizeof(_house_specs));
	memcpy(&_house_specs, &_original_house_specs, sizeof(_original_house_specs));

	/* Reset any overrides that have been set. */
	_house_mngr.ResetOverride();
}