src/tree_cmd.cpp

   1 /* $Id$ */
   2
   3 /*
   4  * This file is part of OpenTTD.
   5  * 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.
   6  * 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.
   7  * 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/>.
   8  */
   9
  10 /** @file tree_cmd.cpp Handling of tree tiles. */
  11
  12 #include "stdafx.h"
  13 #include "clear_map.h"
  14 #include "landscape.h"
  15 #include "tree_map.h"
  16 #include "viewport_func.h"
  17 #include "command_func.h"
  18 #include "town.h"
  19 #include "genworld.h"
  20 #include "clear_func.h"
  21 #include "company_func.h"
  22 #include "sound_func.h"
  23 #include "water.h"
  24 #include "company_base.h"
  25 #include "core/random_func.hpp"
  26 #include "newgrf_generic.h"
  27
  28 #include "table/strings.h"
  29 #include "table/tree_land.h"
  30 #include "table/clear_land.h"
  31
  32 #include "safeguards.h"
  33
  34 /**
  35  * List of tree placer algorithm.
  36  *
  37  * This enumeration defines all possible tree placer algorithm in the game.
  38  */
  39 enum TreePlacer {
  40         TP_NONE,     ///< No tree placer algorithm
  41         TP_ORIGINAL, ///< The original algorithm
  42         TP_IMPROVED, ///< A 'improved' algorithm
  43 };
  44
  45 /** Where to place trees while in-game? */
  46 enum ExtraTreePlacement {
  47         ETP_NONE,       ///< Place trees on no tiles
  48         ETP_RAINFOREST, ///< Place trees only on rainforest tiles
  49         ETP_ALL,        ///< Place trees on all tiles
  50 };
  51
  52 /** Determines when to consider building more trees. */
  53 byte _trees_tick_ctr;
  54
  55 static const uint16 DEFAULT_TREE_STEPS = 1000;             ///< Default number of attempts for placing trees.
  56 static const uint16 DEFAULT_RAINFOREST_TREE_STEPS = 15000; ///< Default number of attempts for placing extra trees at rainforest in tropic.
  57 static const uint16 EDITOR_TREE_DIV = 5;                   ///< Game editor tree generation divisor factor.
  58
  59 /**
  60  * Tests if a tile can be converted to MP_TREES
  61  * This is true for clear ground without farms or rocks.
  62  *
  63  * @param tile the tile of interest
  64  * @param allow_desert Allow planting trees on CLEAR_DESERT?
  65  * @return true if trees can be built.
  66  */
  67 static bool CanPlantTreesOnTile(TileIndex tile, bool allow_desert)
  68 {
  69         switch (GetTileType(tile)) {
  70                 case MP_WATER:
  71                         return !IsBridgeAbove(tile) && IsCoast(tile) && !IsSlopeWithOneCornerRaised(GetTileSlope(tile));
  72
  73                 case MP_CLEAR:
  74                         return !IsBridgeAbove(tile) && !IsClearGround(tile, CLEAR_FIELDS) && GetRawClearGround(tile) != CLEAR_ROCKS &&
  75                                (allow_desert || !IsClearGround(tile, CLEAR_DESERT));
  76
  77                 default: return false;
  78         }
  79 }
  80
  81 /**
  82  * Creates a tree tile
  83  * Ground type and density is preserved.
  84  *
  85  * @pre the tile must be suitable for trees.
  86  *
  87  * @param tile where to plant the trees.
  88  * @param treetype The type of the tree
  89  * @param count the number of trees (minus 1)
  90  * @param growth the growth status
  91  */
  92 static void PlantTreesOnTile(TileIndex tile, TreeType treetype, uint count, uint growth)
  93 {
  94         assert(treetype != TREE_INVALID);
  95         assert(CanPlantTreesOnTile(tile, true));
  96
  97         TreeGround ground;
  98         uint density = 3;
  99
 100         switch (GetTileType(tile)) {
 101                 case MP_WATER:
 102                         ground = TREE_GROUND_SHORE;
 103                         break;
 104
 105                 case MP_CLEAR:
 106                         switch (GetClearGround(tile)) {
 107                                 case CLEAR_GRASS:  ground = TREE_GROUND_GRASS;       break;
 108                                 case CLEAR_ROUGH:  ground = TREE_GROUND_ROUGH;       break;
 109                                 case CLEAR_SNOW:   ground = GetRawClearGround(tile) == CLEAR_ROUGH ? TREE_GROUND_ROUGH_SNOW : TREE_GROUND_SNOW_DESERT; break;
 110                                 default:           ground = TREE_GROUND_SNOW_DESERT; break;
 111                         }
 112                         if (GetClearGround(tile) != CLEAR_ROUGH) density = GetClearDensity(tile);
 113                         break;
 114
 115                 default: NOT_REACHED();
 116         }
 117
 118         MakeTree(tile, treetype, count, growth, ground, density);
 119 }
 120
 121 /**
 122  * Get a random TreeType for the given tile based on a given seed
 123  *
 124  * This function returns a random TreeType which can be placed on the given tile.
 125  * The seed for randomness must be less or equal 256, use #GB on the value of Random()
 126  * to get such a value.
 127  *
 128  * @param tile The tile to get a random TreeType from
 129  * @param seed The seed for randomness, must be less or equal 256
 130  * @return The random tree type
 131  */
 132 static TreeType GetRandomTreeType(TileIndex tile, uint seed)
 133 {
 134         switch (_settings_game.game_creation.landscape) {
 135                 case LT_TEMPERATE:
 136                         return (TreeType)(seed * TREE_COUNT_TEMPERATE / 256 + TREE_TEMPERATE);
 137
 138                 case LT_ARCTIC:
 139                         return (TreeType)(seed * TREE_COUNT_SUB_ARCTIC / 256 + TREE_SUB_ARCTIC);
 140
 141                 case LT_TROPIC:
 142                         switch (GetTropicZone(tile)) {
 143                                 case TROPICZONE_NORMAL:  return (TreeType)(seed * TREE_COUNT_SUB_TROPICAL / 256 + TREE_SUB_TROPICAL);
 144                                 case TROPICZONE_DESERT:  return (TreeType)((seed > 12) ? TREE_INVALID : TREE_CACTUS);
 145                                 default:                 return (TreeType)(seed * TREE_COUNT_RAINFOREST / 256 + TREE_RAINFOREST);
 146                         }
 147
 148                 default:
 149                         return (TreeType)(seed * TREE_COUNT_TOYLAND / 256 + TREE_TOYLAND);
 150         }
 151 }
 152
 153 /**
 154  * Make a random tree tile of the given tile
 155  *
 156  * Create a new tree-tile for the given tile. The second parameter is used for
 157  * randomness like type and number of trees.
 158  *
 159  * @param tile The tile to make a tree-tile from
 160  * @param r The randomness value from a Random() value
 161  */
 162 static void PlaceTree(TileIndex tile, uint32 r)
 163 {
 164         TreeType tree = GetRandomTreeType(tile, GB(r, 24, 8));
 165
 166         if (tree != TREE_INVALID) {
 167                 PlantTreesOnTile(tile, tree, GB(r, 22, 2), min(GB(r, 16, 3), 6));
 168
 169                 /* Rerandomize ground, if neither snow nor shore */
 170                 TreeGround ground = GetTreeGround(tile);
 171                 if (ground != TREE_GROUND_SNOW_DESERT && ground != TREE_GROUND_ROUGH_SNOW && ground != TREE_GROUND_SHORE) {
 172                         SetTreeGroundDensity(tile, (TreeGround)GB(r, 28, 1), 3);
 173                 }
 174
 175                 /* Set the counter to a random start value */
 176                 SetTreeCounter(tile, (TreeGround)GB(r, 24, 4));
 177         }
 178 }
 179
 180 /**
 181  * Creates a number of tree groups.
 182  * The number of trees in each group depends on how many trees are actually placed around the given tile.
 183  *
 184  * @param num_groups Number of tree groups to place.
 185  */
 186 static void PlaceTreeGroups(uint num_groups)
 187 {
 188         do {
 189                 TileIndex center_tile = RandomTile();
 190
 191                 for (uint i = 0; i < DEFAULT_TREE_STEPS; i++) {
 192                         uint32 r = Random();
 193                         int x = GB(r, 0, 5) - 16;
 194                         int y = GB(r, 8, 5) - 16;
 195                         uint dist = abs(x) + abs(y);
 196                         TileIndex cur_tile = TileAddWrap(center_tile, x, y);
 197
 198                         IncreaseGeneratingWorldProgress(GWP_TREE);
 199
 200                         if (cur_tile != INVALID_TILE && dist <= 13 && CanPlantTreesOnTile(cur_tile, true)) {
 201                                 PlaceTree(cur_tile, r);
 202                         }
 203                 }
 204
 205         } while (--num_groups);
 206 }
 207
 208 /**
 209  * Place a tree at the same height as an existing tree.
 210  *
 211  * Add a new tree around the given tile which is at the same
 212  * height or at some offset (2 units) of it.
 213  *
 214  * @param tile The base tile to add a new tree somewhere around
 215  * @param height The height (like the one from the tile)
 216  */
 217 static void PlaceTreeAtSameHeight(TileIndex tile, int height)
 218 {
 219         for (uint i = 0; i < DEFAULT_TREE_STEPS; i++) {
 220                 uint32 r = Random();
 221                 int x = GB(r, 0, 5) - 16;
 222                 int y = GB(r, 8, 5) - 16;
 223                 TileIndex cur_tile = TileAddWrap(tile, x, y);
 224                 if (cur_tile == INVALID_TILE) continue;
 225
 226                 /* Keep in range of the existing tree */
 227                 if (abs(x) + abs(y) > 16) continue;
 228
 229                 /* Clear tile, no farm-tiles or rocks */
 230                 if (!CanPlantTreesOnTile(cur_tile, true)) continue;
 231
 232                 /* Not too much height difference */
 233                 if (Delta(GetTileZ(cur_tile), height) > 2) continue;
 234
 235                 /* Place one tree and quit */
 236                 PlaceTree(cur_tile, r);
 237                 break;
 238         }
 239 }
 240
 241 /**
 242  * Place some trees randomly
 243  *
 244  * This function just place some trees randomly on the map.
 245  */
 246 void PlaceTreesRandomly()
 247 {
 248         int i, j, ht;
 249
 250         i = ScaleByMapSize(DEFAULT_TREE_STEPS);
 251         if (_game_mode == GM_EDITOR) i /= EDITOR_TREE_DIV;
 252         do {
 253                 uint32 r = Random();
 254                 TileIndex tile = RandomTileSeed(r);
 255
 256                 IncreaseGeneratingWorldProgress(GWP_TREE);
 257
 258                 if (CanPlantTreesOnTile(tile, true)) {
 259                         PlaceTree(tile, r);
 260                         if (_settings_game.game_creation.tree_placer != TP_IMPROVED) continue;
 261
 262                         /* Place a number of trees based on the tile height.
 263                          *  This gives a cool effect of multiple trees close together.
 264                          *  It is almost real life ;) */
 265                         ht = GetTileZ(tile);
 266                         /* The higher we get, the more trees we plant */
 267                         j = GetTileZ(tile) * 2;
 268                         /* Above snowline more trees! */
 269                         if (_settings_game.game_creation.landscape == LT_ARCTIC && ht > GetSnowLine()) j *= 3;
 270                         while (j--) {
 271                                 PlaceTreeAtSameHeight(tile, ht);
 272                         }
 273                 }
 274         } while (--i);
 275
 276         /* place extra trees at rainforest area */
 277         if (_settings_game.game_creation.landscape == LT_TROPIC) {
 278                 i = ScaleByMapSize(DEFAULT_RAINFOREST_TREE_STEPS);
 279                 if (_game_mode == GM_EDITOR) i /= EDITOR_TREE_DIV;
 280
 281                 do {
 282                         uint32 r = Random();
 283                         TileIndex tile = RandomTileSeed(r);
 284
 285                         IncreaseGeneratingWorldProgress(GWP_TREE);
 286
 287                         if (GetTropicZone(tile) == TROPICZONE_RAINFOREST && CanPlantTreesOnTile(tile, false)) {
 288                                 PlaceTree(tile, r);
 289                         }
 290                 } while (--i);
 291         }
 292 }
 293
 294 /**
 295  * Place new trees.
 296  *
 297  * This function takes care of the selected tree placer algorithm and
 298  * place randomly the trees for a new game.
 299  */
 300 void GenerateTrees()
 301 {
 302         uint i, total;
 303
 304         if (_settings_game.game_creation.tree_placer == TP_NONE) return;
 305
 306         switch (_settings_game.game_creation.tree_placer) {
 307                 case TP_ORIGINAL: i = _settings_game.game_creation.landscape == LT_ARCTIC ? 15 : 6; break;
 308                 case TP_IMPROVED: i = _settings_game.game_creation.landscape == LT_ARCTIC ?  4 : 2; break;
 309                 default: NOT_REACHED();
 310         }
 311
 312         total = ScaleByMapSize(DEFAULT_TREE_STEPS);
 313         if (_settings_game.game_creation.landscape == LT_TROPIC) total += ScaleByMapSize(DEFAULT_RAINFOREST_TREE_STEPS);
 314         total *= i;
 315         uint num_groups = (_settings_game.game_creation.landscape != LT_TOYLAND) ? ScaleByMapSize(GB(Random(), 0, 5) + 25) : 0;
 316         total += num_groups * DEFAULT_TREE_STEPS;
 317         SetGeneratingWorldProgress(GWP_TREE, total);
 318
 319         if (num_groups != 0) PlaceTreeGroups(num_groups);
 320
 321         for (; i != 0; i--) {
 322                 PlaceTreesRandomly();
 323         }
 324 }
 325
 326 /**
 327  * Plant a tree.
 328  * @param tile end tile of area-drag
 329  * @param flags type of operation
 330  * @param p1 tree type, TREE_INVALID means random.
 331  * @param p2 start tile of area-drag of tree plantation
 332  * @param text unused
 333  * @return the cost of this operation or an error
 334  */
 335 CommandCost CmdPlantTree(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
 336 {
 337         StringID msg = INVALID_STRING_ID;
 338         CommandCost cost(EXPENSES_OTHER);
 339         const byte tree_to_plant = GB(p1, 0, 8); // We cannot use Extract as min and max are climate specific.
 340
 341         if (p2 >= MapSize()) return CMD_ERROR;
 342         /* Check the tree type within the current climate */
 343         if (tree_to_plant != TREE_INVALID && !IsInsideBS(tree_to_plant, _tree_base_by_landscape[_settings_game.game_creation.landscape], _tree_count_by_landscape[_settings_game.game_creation.landscape])) return CMD_ERROR;
 344
 345         Company *c = (_game_mode != GM_EDITOR) ? Company::GetIfValid(_current_company) : NULL;
 346         int limit = (c == NULL ? INT32_MAX : GB(c->tree_limit, 16, 16));
 347
 348         TileArea ta(tile, p2);
 349         TILE_AREA_LOOP(tile, ta) {
 350                 switch (GetTileType(tile)) {
 351                         case MP_TREES:
 352                                 /* no more space for trees? */
 353                                 if (_game_mode != GM_EDITOR && GetTreeCount(tile) == 4) {
 354                                         msg = STR_ERROR_TREE_ALREADY_HERE;
 355                                         continue;
 356                                 }
 357
 358                                 /* Test tree limit. */
 359                                 if (--limit < 1) {
 360                                         msg = STR_ERROR_TREE_PLANT_LIMIT_REACHED;
 361                                         break;
 362                                 }
 363
 364                                 if (flags & DC_EXEC) {
 365                                         AddTreeCount(tile, 1);
 366                                         MarkTileDirtyByTile(tile);
 367                                         if (c != NULL) c->tree_limit -= 1 << 16;
 368                                 }
 369                                 /* 2x as expensive to add more trees to an existing tile */
 370                                 cost.AddCost(_price[PR_BUILD_TREES] * 2);
 371                                 break;
 372
 373                         case MP_WATER:
 374                                 if (!IsCoast(tile) || IsSlopeWithOneCornerRaised(GetTileSlope(tile))) {
 375                                         msg = STR_ERROR_CAN_T_BUILD_ON_WATER;
 376                                         continue;
 377                                 }
 378                                 FALLTHROUGH;
 379
 380                         case MP_CLEAR: {
 381                                 if (IsBridgeAbove(tile)) {
 382                                         msg = STR_ERROR_SITE_UNSUITABLE;
 383                                         continue;
 384                                 }
 385
 386                                 TreeType treetype = (TreeType)tree_to_plant;
 387                                 /* Be a bit picky about which trees go where. */
 388                                 if (_settings_game.game_creation.landscape == LT_TROPIC && treetype != TREE_INVALID && (
 389                                                 /* No cacti outside the desert */
 390                                                 (treetype == TREE_CACTUS && GetTropicZone(tile) != TROPICZONE_DESERT) ||
 391                                                 /* No rain forest trees outside the rain forest, except in the editor mode where it makes those tiles rain forest tile */
 392                                                 (IsInsideMM(treetype, TREE_RAINFOREST, TREE_CACTUS) && GetTropicZone(tile) != TROPICZONE_RAINFOREST && _game_mode != GM_EDITOR) ||
 393                                                 /* And no subtropical trees in the desert/rain forest */
 394                                                 (IsInsideMM(treetype, TREE_SUB_TROPICAL, TREE_TOYLAND) && GetTropicZone(tile) != TROPICZONE_NORMAL))) {
 395                                         msg = STR_ERROR_TREE_WRONG_TERRAIN_FOR_TREE_TYPE;
 396                                         continue;
 397                                 }
 398
 399                                 /* Test tree limit. */
 400                                 if (--limit < 1) {
 401                                         msg = STR_ERROR_TREE_PLANT_LIMIT_REACHED;
 402                                         break;
 403                                 }
 404
 405                                 if (IsTileType(tile, MP_CLEAR)) {
 406                                         /* Remove fields or rocks. Note that the ground will get barrened */
 407                                         switch (GetRawClearGround(tile)) {
 408                                                 case CLEAR_FIELDS:
 409                                                 case CLEAR_ROCKS: {
 410                                                         CommandCost ret = DoCommand(tile, 0, 0, flags, CMD_LANDSCAPE_CLEAR);
 411                                                         if (ret.Failed()) return ret;
 412                                                         cost.AddCost(ret);
 413                                                         break;
 414                                                 }
 415
 416                                                 default: break;
 417                                         }
 418                                 }
 419
 420                                 if (_game_mode != GM_EDITOR && Company::IsValidID(_current_company)) {
 421                                         Town *t = ClosestTownFromTile(tile, _settings_game.economy.dist_local_authority);
 422                                         if (t != NULL) ChangeTownRating(t, RATING_TREE_UP_STEP, RATING_TREE_MAXIMUM, flags);
 423                                 }
 424
 425                                 if (flags & DC_EXEC) {
 426                                         if (treetype == TREE_INVALID) {
 427                                                 treetype = GetRandomTreeType(tile, GB(Random(), 24, 8));
 428                                                 if (treetype == TREE_INVALID) treetype = TREE_CACTUS;
 429                                         }
 430
 431                                         /* Plant full grown trees in scenario editor */
 432                                         PlantTreesOnTile(tile, treetype, 0, _game_mode == GM_EDITOR ? 3 : 0);
 433                                         MarkTileDirtyByTile(tile);
 434                                         if (c != NULL) c->tree_limit -= 1 << 16;
 435
 436                                         /* When planting rainforest-trees, set tropiczone to rainforest in editor. */
 437                                         if (_game_mode == GM_EDITOR && IsInsideMM(treetype, TREE_RAINFOREST, TREE_CACTUS)) {
 438                                                 SetTropicZone(tile, TROPICZONE_RAINFOREST);
 439                                         }
 440                                 }
 441                                 cost.AddCost(_price[PR_BUILD_TREES]);
 442                                 break;
 443                         }
 444
 445                         default:
 446                                 msg = STR_ERROR_SITE_UNSUITABLE;
 447                                 break;
 448                 }
 449
 450                 /* Tree limit used up? No need to check more. */
 451                 if (limit < 0) break;
 452         }
 453
 454         if (cost.GetCost() == 0) {
 455                 return_cmd_error(msg);
 456         } else {
 457                 return cost;
 458         }
 459 }
 460
 461 struct TreeListEnt : PalSpriteID {
 462         byte x, y;
 463 };
 464
 465 static void DrawTile_Trees(TileInfo *ti)
 466 {
 467         switch (GetTreeGround(ti->tile)) {
 468                 case TREE_GROUND_SHORE: DrawShoreTile(ti->tileh); break;
 469                 case TREE_GROUND_GRASS: DrawClearLandTile(ti, GetTreeDensity(ti->tile)); break;
 470                 case TREE_GROUND_ROUGH: DrawHillyLandTile(ti); break;
 471                 default: DrawGroundSprite(_clear_land_sprites_snow_desert[GetTreeDensity(ti->tile)] + SlopeToSpriteOffset(ti->tileh), PAL_NONE); break;
 472         }
 473
 474         /* Do not draw trees when the invisible trees setting is set */
 475         if (IsInvisibilitySet(TO_TREES)) return;
 476
 477         uint tmp = CountBits(ti->tile + ti->x + ti->y);
 478         uint index = GB(tmp, 0, 2) + (GetTreeType(ti->tile) << 2);
 479
 480         /* different tree styles above one of the grounds */
 481         if ((GetTreeGround(ti->tile) == TREE_GROUND_SNOW_DESERT || GetTreeGround(ti->tile) == TREE_GROUND_ROUGH_SNOW) &&
 482                         GetTreeDensity(ti->tile) >= 2 &&
 483                         IsInsideMM(index, TREE_SUB_ARCTIC << 2, TREE_RAINFOREST << 2)) {
 484                 index += 164 - (TREE_SUB_ARCTIC << 2);
 485         }
 486
 487         assert(index < lengthof(_tree_layout_sprite));
 488
 489         const PalSpriteID *s = _tree_layout_sprite[index];
 490         const TreePos *d = _tree_layout_xy[GB(tmp, 2, 2)];
 491
 492         /* combine trees into one sprite object */
 493         StartSpriteCombine();
 494
 495         TreeListEnt te[4];
 496
 497         /* put the trees to draw in a list */
 498         uint trees = GetTreeCount(ti->tile);
 499
 500         for (uint i = 0; i < trees; i++) {
 501                 SpriteID sprite = s[0].sprite + (i == trees - 1 ? GetTreeGrowth(ti->tile) : 3);
 502                 PaletteID pal = s[0].pal;
 503
 504                 te[i].sprite = sprite;
 505                 te[i].pal    = pal;
 506                 te[i].x = d->x;
 507                 te[i].y = d->y;
 508                 s++;
 509                 d++;
 510         }
 511
 512         /* draw them in a sorted way */
 513         int z = ti->z + GetSlopeMaxPixelZ(ti->tileh) / 2;
 514
 515         for (; trees > 0; trees--) {
 516                 uint min = te[0].x + te[0].y;
 517                 uint mi = 0;
 518
 519                 for (uint i = 1; i < trees; i++) {
 520                         if ((uint)(te[i].x + te[i].y) < min) {
 521                                 min = te[i].x + te[i].y;
 522                                 mi = i;
 523                         }
 524                 }
 525
 526                 AddSortableSpriteToDraw(te[mi].sprite, te[mi].pal, ti->x + te[mi].x, ti->y + te[mi].y, 16 - te[mi].x, 16 - te[mi].y, 0x30, z, IsTransparencySet(TO_TREES), -te[mi].x, -te[mi].y);
 527
 528                 /* replace the removed one with the last one */
 529                 te[mi] = te[trees - 1];
 530         }
 531
 532         EndSpriteCombine();
 533 }
 534
 535
 536 static int GetSlopePixelZ_Trees(TileIndex tile, uint x, uint y)
 537 {
 538         int z;
 539         Slope tileh = GetTilePixelSlope(tile, &z);
 540
 541         return z + GetPartialPixelZ(x & 0xF, y & 0xF, tileh);
 542 }
 543
 544 static Foundation GetFoundation_Trees(TileIndex tile, Slope tileh)
 545 {
 546         return FOUNDATION_NONE;
 547 }
 548
 549 static CommandCost ClearTile_Trees(TileIndex tile, DoCommandFlag flags)
 550 {
 551         uint num;
 552
 553         if (Company::IsValidID(_current_company)) {
 554                 Town *t = ClosestTownFromTile(tile, _settings_game.economy.dist_local_authority);
 555                 if (t != NULL) ChangeTownRating(t, RATING_TREE_DOWN_STEP, RATING_TREE_MINIMUM, flags);
 556         }
 557
 558         num = GetTreeCount(tile);
 559         if (IsInsideMM(GetTreeType(tile), TREE_RAINFOREST, TREE_CACTUS)) num *= 4;
 560
 561         if (flags & DC_EXEC) DoClearSquare(tile);
 562
 563         return CommandCost(EXPENSES_CONSTRUCTION, num * _price[PR_CLEAR_TREES]);
 564 }
 565
 566 static void GetTileDesc_Trees(TileIndex tile, TileDesc *td)
 567 {
 568         TreeType tt = GetTreeType(tile);
 569
 570         if (IsInsideMM(tt, TREE_RAINFOREST, TREE_CACTUS)) {
 571                 td->str = STR_LAI_TREE_NAME_RAINFOREST;
 572         } else {
 573                 td->str = tt == TREE_CACTUS ? STR_LAI_TREE_NAME_CACTUS_PLANTS : STR_LAI_TREE_NAME_TREES;
 574         }
 575
 576         td->owner[0] = GetTileOwner(tile);
 577 }
 578
 579 static void TileLoopTreesDesert(TileIndex tile)
 580 {
 581         switch (GetTropicZone(tile)) {
 582                 case TROPICZONE_DESERT:
 583                         if (GetTreeGround(tile) != TREE_GROUND_SNOW_DESERT) {
 584                                 SetTreeGroundDensity(tile, TREE_GROUND_SNOW_DESERT, 3);
 585                                 MarkTileDirtyByTile(tile);
 586                         }
 587                         break;
 588
 589                 case TROPICZONE_RAINFOREST: {
 590                         static const SoundFx forest_sounds[] = {
 591                                 SND_42_LOON_BIRD,
 592                                 SND_43_LION,
 593                                 SND_44_MONKEYS,
 594                                 SND_48_DISTANT_BIRD
 595                         };
 596                         uint32 r = Random();
 597
 598                         if (Chance16I(1, 200, r) && _settings_client.sound.ambient) SndPlayTileFx(forest_sounds[GB(r, 16, 2)], tile);
 599                         break;
 600                 }
 601
 602                 default: break;
 603         }
 604 }
 605
 606 static void TileLoopTreesAlps(TileIndex tile)
 607 {
 608         int k = GetTileZ(tile) - GetSnowLine() + 1;
 609
 610         if (k < 0) {
 611                 switch (GetTreeGround(tile)) {
 612                         case TREE_GROUND_SNOW_DESERT: SetTreeGroundDensity(tile, TREE_GROUND_GRASS, 3); break;
 613                         case TREE_GROUND_ROUGH_SNOW:  SetTreeGroundDensity(tile, TREE_GROUND_ROUGH, 3); break;
 614                         default: return;
 615                 }
 616         } else {
 617                 uint density = min<uint>(k, 3);
 618
 619                 if (GetTreeGround(tile) != TREE_GROUND_SNOW_DESERT && GetTreeGround(tile) != TREE_GROUND_ROUGH_SNOW) {
 620                         TreeGround tg = GetTreeGround(tile) == TREE_GROUND_ROUGH ? TREE_GROUND_ROUGH_SNOW : TREE_GROUND_SNOW_DESERT;
 621                         SetTreeGroundDensity(tile, tg, density);
 622                 } else if (GetTreeDensity(tile) != density) {
 623                         SetTreeGroundDensity(tile, GetTreeGround(tile), density);
 624                 } else {
 625                         if (GetTreeDensity(tile) == 3) {
 626                                 uint32 r = Random();
 627                                 if (Chance16I(1, 200, r) && _settings_client.sound.ambient) {
 628                                         SndPlayTileFx((r & 0x80000000) ? SND_39_HEAVY_WIND : SND_34_WIND, tile);
 629                                 }
 630                         }
 631                         return;
 632                 }
 633         }
 634         MarkTileDirtyByTile(tile);
 635 }
 636
 637 static void TileLoop_Trees(TileIndex tile)
 638 {
 639         if (GetTreeGround(tile) == TREE_GROUND_SHORE) {
 640                 TileLoop_Water(tile);
 641         } else {
 642                 switch (_settings_game.game_creation.landscape) {
 643                         case LT_TROPIC: TileLoopTreesDesert(tile); break;
 644                         case LT_ARCTIC: TileLoopTreesAlps(tile);   break;
 645                 }
 646         }
 647
 648         AmbientSoundEffect(tile);
 649
 650         uint treeCounter = GetTreeCounter(tile);
 651
 652         /* Handle growth of grass (under trees/on MP_TREES tiles) at every 8th processings, like it's done for grass on MP_CLEAR tiles. */
 653         if ((treeCounter & 7) == 7 && GetTreeGround(tile) == TREE_GROUND_GRASS) {
 654                 uint density = GetTreeDensity(tile);
 655                 if (density < 3) {
 656                         SetTreeGroundDensity(tile, TREE_GROUND_GRASS, density + 1);
 657                         MarkTileDirtyByTile(tile);
 658                 }
 659         }
 660         if (GetTreeCounter(tile) < 15) {
 661                 AddTreeCounter(tile, 1);
 662                 return;
 663         }
 664         SetTreeCounter(tile, 0);
 665
 666         switch (GetTreeGrowth(tile)) {
 667                 case 3: // regular sized tree
 668                         if (_settings_game.game_creation.landscape == LT_TROPIC &&
 669                                         GetTreeType(tile) != TREE_CACTUS &&
 670                                         GetTropicZone(tile) == TROPICZONE_DESERT) {
 671                                 AddTreeGrowth(tile, 1);
 672                         } else {
 673                                 switch (GB(Random(), 0, 3)) {
 674                                         case 0: // start destructing
 675                                                 AddTreeGrowth(tile, 1);
 676                                                 break;
 677
 678                                         case 1: // add a tree
 679                                                 if (GetTreeCount(tile) < 4) {
 680                                                         AddTreeCount(tile, 1);
 681                                                         SetTreeGrowth(tile, 0);
 682                                                         break;
 683                                                 }
 684                                                 FALLTHROUGH;
 685
 686                                         case 2: { // add a neighbouring tree
 687                                                 /* Don't plant extra trees if that's not allowed. */
 688                                                 if ((_settings_game.game_creation.landscape == LT_TROPIC && GetTropicZone(tile) == TROPICZONE_RAINFOREST) ?
 689                                                                 _settings_game.construction.extra_tree_placement == ETP_NONE :
 690                                                                 _settings_game.construction.extra_tree_placement != ETP_ALL) {
 691                                                         break;
 692                                                 }
 693
 694                                                 TreeType treetype = GetTreeType(tile);
 695
 696                                                 tile += TileOffsByDir((Direction)(Random() & 7));
 697
 698                                                 /* Cacti don't spread */
 699                                                 if (!CanPlantTreesOnTile(tile, false)) return;
 700
 701                                                 /* Don't plant trees, if ground was freshly cleared */
 702                                                 if (IsTileType(tile, MP_CLEAR) && GetClearGround(tile) == CLEAR_GRASS && GetClearDensity(tile) != 3) return;
 703
 704                                                 PlantTreesOnTile(tile, treetype, 0, 0);
 705
 706                                                 break;
 707                                         }
 708
 709                                         default:
 710                                                 return;
 711                                 }
 712                         }
 713                         break;
 714
 715                 case 6: // final stage of tree destruction
 716                         if (GetTreeCount(tile) > 1) {
 717                                 /* more than one tree, delete it */
 718                                 AddTreeCount(tile, -1);
 719                                 SetTreeGrowth(tile, 3);
 720                         } else {
 721                                 /* just one tree, change type into MP_CLEAR */
 722                                 switch (GetTreeGround(tile)) {
 723                                         case TREE_GROUND_SHORE: MakeShore(tile); break;
 724                                         case TREE_GROUND_GRASS: MakeClear(tile, CLEAR_GRASS, GetTreeDensity(tile)); break;
 725                                         case TREE_GROUND_ROUGH: MakeClear(tile, CLEAR_ROUGH, 3); break;
 726                                         case TREE_GROUND_ROUGH_SNOW: {
 727                                                 uint density = GetTreeDensity(tile);
 728                                                 MakeClear(tile, CLEAR_ROUGH, 3);
 729                                                 MakeSnow(tile, density);
 730                                                 break;
 731                                         }
 732                                         default: // snow or desert
 733                                                 if (_settings_game.game_creation.landscape == LT_TROPIC) {
 734                                                         MakeClear(tile, CLEAR_DESERT, GetTreeDensity(tile));
 735                                                 } else {
 736                                                         uint density = GetTreeDensity(tile);
 737                                                         MakeClear(tile, CLEAR_GRASS, 3);
 738                                                         MakeSnow(tile, density);
 739                                                 }
 740                                                 break;
 741                                 }
 742                         }
 743                         break;
 744
 745                 default:
 746                         AddTreeGrowth(tile, 1);
 747                         break;
 748         }
 749
 750         MarkTileDirtyByTile(tile);
 751 }
 752
 753 void OnTick_Trees()
 754 {
 755         /* Don't place trees if that's not allowed */
 756         if (_settings_game.construction.extra_tree_placement == ETP_NONE) return;
 757
 758         uint32 r;
 759         TileIndex tile;
 760         TreeType tree;
 761
 762         /* place a tree at a random rainforest spot */
 763         if (_settings_game.game_creation.landscape == LT_TROPIC &&
 764                         (r = Random(), tile = RandomTileSeed(r), GetTropicZone(tile) == TROPICZONE_RAINFOREST) &&
 765                         CanPlantTreesOnTile(tile, false) &&
 766                         (tree = GetRandomTreeType(tile, GB(r, 24, 8))) != TREE_INVALID) {
 767                 PlantTreesOnTile(tile, tree, 0, 0);
 768         }
 769
 770         /* byte underflow */
 771         if (--_trees_tick_ctr != 0 || _settings_game.construction.extra_tree_placement != ETP_ALL) return;
 772
 773         /* place a tree at a random spot */
 774         r = Random();
 775         tile = RandomTileSeed(r);
 776         if (CanPlantTreesOnTile(tile, false) && (tree = GetRandomTreeType(tile, GB(r, 24, 8))) != TREE_INVALID) {
 777                 PlantTreesOnTile(tile, tree, 0, 0);
 778         }
 779 }
 780
 781 static TrackStatus GetTileTrackStatus_Trees(TileIndex tile, TransportType mode, uint sub_mode, DiagDirection side)
 782 {
 783         return 0;
 784 }
 785
 786 static void ChangeTileOwner_Trees(TileIndex tile, Owner old_owner, Owner new_owner)
 787 {
 788         /* not used */
 789 }
 790
 791 void InitializeTrees()
 792 {
 793         _trees_tick_ctr = 0;
 794 }
 795
 796 static CommandCost TerraformTile_Trees(TileIndex tile, DoCommandFlag flags, int z_new, Slope tileh_new)
 797 {
 798         return DoCommand(tile, 0, 0, flags, CMD_LANDSCAPE_CLEAR);
 799 }
 800
 801
 802 extern const TileTypeProcs _tile_type_trees_procs = {
 803         DrawTile_Trees,           // draw_tile_proc
 804         GetSlopePixelZ_Trees,     // get_slope_z_proc
 805         ClearTile_Trees,          // clear_tile_proc
 806         NULL,                     // add_accepted_cargo_proc
 807         GetTileDesc_Trees,        // get_tile_desc_proc
 808         GetTileTrackStatus_Trees, // get_tile_track_status_proc
 809         NULL,                     // click_tile_proc
 810         NULL,                     // animate_tile_proc
 811         TileLoop_Trees,           // tile_loop_proc
 812         ChangeTileOwner_Trees,    // change_tile_owner_proc
 813         NULL,                     // add_produced_cargo_proc
 814         NULL,                     // vehicle_enter_tile_proc
 815         GetFoundation_Trees,      // get_foundation_proc
 816         TerraformTile_Trees,      // terraform_tile_proc
 817 };