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 mod/// ify 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                         bool is_above_tree_line = GetTileZ(tile) >= _settings_game.game_creation.tree_line_height;
  75
  76                         return !is_above_tree_line && !IsBridgeAbove(tile) && !IsClearGround(tile, CLEAR_FIELDS) && GetRawClearGround(tile) != CLEAR_ROCKS &&
  77                                 (allow_desert || !IsClearGround(tile, CLEAR_DESERT));
  78                 }
  79
  80                 default: return false;
  81         }
  82 }
  83
  84 /**
  85  * Creates a tree tile
  86  * Ground type and density is preserved.
  87  *
  88  * @pre the tile must be suitable for trees.
  89  *
  90  * @param tile where to plant the trees.
  91  * @param treetype The type of the tree
  92  * @param count the number of trees (minus 1)
  93  * @param growth the growth status
  94  */
  95 static void PlantTreesOnTile(TileIndex tile, TreeType treetype, uint count, uint growth)
  96 {
  97         assert(treetype != TREE_INVALID);
  98         assert(CanPlantTreesOnTile(tile, true));
  99
 100         TreeGround ground;
 101         uint density = 3;
 102
 103         switch (GetTileType(tile)) {
 104                 case MP_WATER:
 105                         ground = TREE_GROUND_SHORE;
 106                         break;
 107
 108                 case MP_CLEAR:
 109                         switch (GetClearGround(tile)) {
 110                                 case CLEAR_GRASS:  ground = TREE_GROUND_GRASS;       break;
 111                                 case CLEAR_ROUGH:  ground = TREE_GROUND_ROUGH;       break;
 112                                 case CLEAR_SNOW:   ground = GetRawClearGround(tile) == CLEAR_ROUGH ? TREE_GROUND_ROUGH_SNOW : TREE_GROUND_SNOW_DESERT; break;
 113                                 default:           ground = TREE_GROUND_SNOW_DESERT; break;
 114                         }
 115                         if (GetClearGround(tile) != CLEAR_ROUGH) density = GetClearDensity(tile);
 116                         break;
 117
 118                 default: NOT_REACHED();
 119         }
 120
 121         uint16 tree_line_range = _settings_game.construction.trees_around_snow_line_range;
 122         uint16 min_tree_line_height = _settings_game.game_creation.tree_line_height - tree_line_range;
 123
 124         if (GetTileZ(tile) >= min_tree_line_height) {
 125                 // Slowly thin out trees.
 126                 uint16 height_above_min_tree_line = max(0, GetTileZ(tile) - min_tree_line_height);
 127                 uint16 percent_of_range = 100u - (height_above_min_tree_line * 100u / tree_line_range);
 128
 129                 count = max((count * percent_of_range) / 100u, 1u);
 130         }
 131
 132         MakeTree(tile, treetype, count, growth, ground, density);
 133 }
 134
 135 /**
 136 * Previous value of _settings_game.construction.trees_around_snow_line_range
 137 * used to calculate _arctic_tree_occurance
 138 */
 139 static uint8 _previous_trees_around_snow_line_range = 255;
 140
 141 /**
 142 * Array of probabilities for artic trees to appear,
 143 * by normalised distance from snow line
 144 */
 145 static uint8 _arctic_tree_occurance[24];
 146
 147 /** Recalculate _arctic_tree_occurance */
 148 static void RecalculateArcticTreeOccuranceArray()
 149 {
 150         /*
 151         * Approximate: 256 * exp(-3 * distance / range)
 152         * By using:
 153         * 256 * ((1 + (-3 * distance / range) / 6) ** 6)
 154         * ((256 - (128 * distance / range)) ** 6) >> (5 * 8);
 155         */
 156         uint8 range = _settings_game.construction.trees_around_snow_line_range;
 157         _previous_trees_around_snow_line_range = range;
 158         _arctic_tree_occurance[0] = 255;
 159         uint i = 1;
 160         for (; i < lengthof(_arctic_tree_occurance); i++) {
 161                 if (range == 0) break;
 162                 uint x = 256 - ((128 * i) / range);
 163                 uint32 output = x;
 164                 output *= x;
 165                 output *= x;
 166                 output *= x;
 167                 output >>= 16;
 168                 output *= x;
 169                 output *= x;
 170                 output >>= 24;
 171                 if (output == 0) break;
 172                 _arctic_tree_occurance[i] = output;
 173         }
 174         for (; i < lengthof(_arctic_tree_occurance); i++) {
 175                 _arctic_tree_occurance[i] = 0;
 176         }
 177 }
 178
 179 /**
 180  * Get a random TreeType for the given tile based on a given seed
 181  *
 182  * This function returns a random TreeType which can be placed on the given tile.
 183  * The seed for randomness must be less than 256, use #GB on the value of Random()
 184  * to get such a value.
 185  *
 186  * @param tile The tile to get a random TreeType from
 187  * @param seed The seed for randomness, must be less than 256
 188  * @return The random tree type
 189  */
 190 static TreeType GetRandomTreeType(TileIndex tile, uint seed)
 191 {
 192         switch (_settings_game.game_creation.landscape) {
 193                 case LT_TEMPERATE:
 194                         if (!_settings_game.construction.trees_around_snow_line_enabled) {
 195                                 return (TreeType)(seed * TREE_COUNT_TEMPERATE / 256 + TREE_TEMPERATE);
 196                         }
 197                 case LT_ARCTIC: {
 198                         // Don't use temperate trees in arctic if a variable snow line is set. That will look awful.
 199                         if (IsSnowLineSet()) {
 200                                 return (TreeType)(seed * TREE_COUNT_SUB_ARCTIC / 256 + TREE_SUB_ARCTIC);
 201                         }
 202
 203                         uint8 tree_line_range = _settings_game.construction.trees_around_snow_line_range;
 204                         if (tree_line_range != _previous_trees_around_snow_line_range) RecalculateArcticTreeOccuranceArray();
 205
 206                         int z = GetTileZ(tile);
 207                         int height_above_snow_line = z - _settings_game.game_creation.snow_line_height;
 208                         uint normalised_distance = (height_above_snow_line < 0) ? -height_above_snow_line : height_above_snow_line + 1;
 209                         bool arctic_tree = false;
 210                         if (normalised_distance < lengthof(_arctic_tree_occurance)) {
 211                                 uint adjusted_seed = (seed ^ tile) & 0xFF;
 212                                 arctic_tree = adjusted_seed < _arctic_tree_occurance[normalised_distance];
 213                         }
 214                         if (height_above_snow_line < 0) {
 215                                 /* Below snow level mixed forest. */
 216                                 return (arctic_tree) ? (TreeType)(seed * TREE_COUNT_SUB_ARCTIC / 256 + TREE_SUB_ARCTIC) : (TreeType)(seed * TREE_COUNT_TEMPERATE / 256 + TREE_TEMPERATE);
 217                         }
 218                         else {
 219                                 /* Above is Arctic trees and thinning out. */
 220                                 return (arctic_tree) ? (TreeType)(seed * TREE_COUNT_SUB_ARCTIC / 256 + TREE_SUB_ARCTIC) : TREE_INVALID;
 221                         }
 222                 }
 223
 224                 case LT_TROPIC:
 225                         switch (GetTropicZone(tile)) {
 226                                 case TROPICZONE_NORMAL:  return (TreeType)(seed * TREE_COUNT_SUB_TROPICAL / 256 + TREE_SUB_TROPICAL);
 227                                 case TROPICZONE_DESERT:  return (TreeType)((seed > 12) ? TREE_INVALID : TREE_CACTUS);
 228                                 default:                 return (TreeType)(seed * TREE_COUNT_RAINFOREST / 256 + TREE_RAINFOREST);
 229                         }
 230
 231                 default:
 232                         return (TreeType)(seed * TREE_COUNT_TOYLAND / 256 + TREE_TOYLAND);
 233         }
 234 }
 235
 236 /**
 237  * Make a random tree tile of the given tile
 238  *
 239  * Create a new tree-tile for the given tile. The second parameter is used for
 240  * randomness like type and number of trees.
 241  *
 242  * @param tile The tile to make a tree-tile from
 243  * @param r The randomness value from a Random() value
 244  */
 245 static void PlaceTree(TileIndex tile, uint32 r)
 246 {
 247         TreeType tree = GetRandomTreeType(tile, GB(r, 24, 8));
 248
 249         if (tree != TREE_INVALID) {
 250                 PlantTreesOnTile(tile, tree, GB(r, 22, 2), min(GB(r, 16, 3), 6));
 251
 252                 /* Rerandomize ground, if neither snow nor shore */
 253                 TreeGround ground = GetTreeGround(tile);
 254                 if (ground != TREE_GROUND_SNOW_DESERT && ground != TREE_GROUND_ROUGH_SNOW && ground != TREE_GROUND_SHORE) {
 255                         SetTreeGroundDensity(tile, (TreeGround)GB(r, 28, 1), 3);
 256                 }
 257
 258                 /* Set the counter to a random start value */
 259                 SetTreeCounter(tile, (TreeGround)GB(r, 24, 4));
 260         }
 261 }
 262
 263 /**
 264  * Creates a number of tree groups.
 265  * The number of trees in each group depends on how many trees are actually placed around the given tile.
 266  *
 267  * @param num_groups Number of tree groups to place.
 268  */
 269 static void PlaceTreeGroups(uint num_groups)
 270 {
 271         do {
 272                 TileIndex center_tile = RandomTile();
 273
 274                 for (uint i = 0; i < DEFAULT_TREE_STEPS; i++) {
 275                         uint32 r = Random();
 276                         int x = GB(r, 0, 5) - 16;
 277                         int y = GB(r, 8, 5) - 16;
 278                         uint dist = abs(x) + abs(y);
 279                         TileIndex cur_tile = TileAddWrap(center_tile, x, y);
 280
 281                         IncreaseGeneratingWorldProgress(GWP_TREE);
 282
 283                         if (cur_tile != INVALID_TILE && dist <= 13 && CanPlantTreesOnTile(cur_tile, true)) {
 284                                 PlaceTree(cur_tile, r);
 285                         }
 286                 }
 287
 288         } while (--num_groups);
 289 }
 290
 291 /**
 292  * Place a tree at the same height as an existing tree.
 293  *
 294  * Add a new tree around the given tile which is at the same
 295  * height or at some offset (2 units) of it.
 296  *
 297  * @param tile The base tile to add a new tree somewhere around
 298  * @param height The height (like the one from the tile)
 299  */
 300 static void PlaceTreeAtSameHeight(TileIndex tile, int height)
 301 {
 302         for (uint i = 0; i < DEFAULT_TREE_STEPS; i++) {
 303                 uint32 r = Random();
 304                 int x = GB(r, 0, 5) - 16;
 305                 int y = GB(r, 8, 5) - 16;
 306                 TileIndex cur_tile = TileAddWrap(tile, x, y);
 307
 308                 if (cur_tile == INVALID_TILE) continue;
 309
 310                 /* Keep in range of the existing tree */
 311                 if (abs(x) + abs(y) > 16) continue;
 312
 313                 /* Clear tile, no farm-tiles or rocks */
 314                 if (!CanPlantTreesOnTile(cur_tile, true)) continue;
 315
 316                 /* Not too much height difference */
 317                 if (Delta(GetTileZ(cur_tile), height) > 2) continue;
 318
 319                 /* Place one tree and quit */
 320                 PlaceTree(cur_tile, r);
 321                 break;
 322         }
 323 }
 324
 325 /**
 326  * Place some trees randomly
 327  *
 328  * This function just place some trees randomly on the map.
 329  */
 330 void PlaceTreesRandomly()
 331 {
 332         int i, j, ht;
 333
 334         i = ScaleByMapSize(DEFAULT_TREE_STEPS);
 335         if (_game_mode == GM_EDITOR) i /= EDITOR_TREE_DIV;
 336         do {
 337                 uint32 r = Random();
 338                 TileIndex tile = RandomTileSeed(r);
 339
 340                 IncreaseGeneratingWorldProgress(GWP_TREE);
 341
 342                 if (CanPlantTreesOnTile(tile, true)) {
 343                         PlaceTree(tile, r);
 344                         if (_settings_game.game_creation.tree_placer != TP_IMPROVED) continue;
 345
 346                         /* Place a number of trees based on the tile height.
 347                          *  This gives a cool effect of multiple trees close together.
 348                          *  It is almost real life ;) */
 349                         ht = GetTileZ(tile);
 350                         /* The higher we get, the more trees we plant */
 351                         j = max(1, (GetTileZ(tile) - 1) * 2);
 352
 353                         uint16 tree_line_range = _settings_game.construction.trees_around_snow_line_range;
 354                         uint16 min_tree_line_height = _settings_game.game_creation.tree_line_height - tree_line_range;
 355
 356                         if (GetTileZ(tile) >= min_tree_line_height) {
 357                                 // Slowly thin out trees.
 358                                 uint16 height_above_min_tree_line = max(0, GetTileZ(tile) - min_tree_line_height);
 359                                 uint16 percent_of_range = (height_above_min_tree_line * 100u / tree_line_range);
 360
 361                                 j = j - ((j * percent_of_range) / 100u);
 362                         } else if (_settings_game.game_creation.landscape == LT_ARCTIC && ht > GetSnowLine()) {
 363                                 // Above snowline more trees.
 364                                 j *= 3;
 365                         }
 366                         while (j--) {
 367                                 PlaceTreeAtSameHeight(tile, ht);
 368                         }
 369                 }
 370         } while (--i);
 371
 372         /* place extra trees at rainforest area */
 373         if (_settings_game.game_creation.landscape == LT_TROPIC) {
 374                 i = ScaleByMapSize(DEFAULT_RAINFOREST_TREE_STEPS);
 375                 if (_game_mode == GM_EDITOR) i /= EDITOR_TREE_DIV;
 376
 377                 do {
 378                         uint32 r = Random();
 379                         TileIndex tile = RandomTileSeed(r);
 380
 381                         IncreaseGeneratingWorldProgress(GWP_TREE);
 382
 383                         if (GetTropicZone(tile) == TROPICZONE_RAINFOREST && CanPlantTreesOnTile(tile, false)) {
 384                                 PlaceTree(tile, r);
 385                         }
 386                 } while (--i);
 387         }
 388 }
 389
 390 /**
 391  * Place new trees.
 392  *
 393  * This function takes care of the selected tree placer algorithm and
 394  * place randomly the trees for a new game.
 395  */
 396 void GenerateTrees()
 397 {
 398         uint i, total;
 399
 400         if (_settings_game.game_creation.tree_placer == TP_NONE) return;
 401
 402         switch (_settings_game.game_creation.tree_placer) {
 403                 case TP_ORIGINAL: i = _settings_game.game_creation.landscape == LT_ARCTIC ? 15 : 6; break;
 404                 case TP_IMPROVED: i = _settings_game.game_creation.landscape == LT_ARCTIC ?  4 : 2; break;
 405                 default: NOT_REACHED();
 406         }
 407
 408         total = ScaleByMapSize(DEFAULT_TREE_STEPS);
 409         if (_settings_game.game_creation.landscape == LT_TROPIC) total += ScaleByMapSize(DEFAULT_RAINFOREST_TREE_STEPS);
 410         total *= i;
 411         uint num_groups = (_settings_game.game_creation.landscape != LT_TOYLAND) ? ScaleByMapSize(GB(Random(), 0, 5) + 25) : 0;
 412         total += num_groups * DEFAULT_TREE_STEPS;
 413         SetGeneratingWorldProgress(GWP_TREE, total);
 414
 415         if (num_groups != 0) PlaceTreeGroups(num_groups);
 416
 417         for (; i != 0; i--) {
 418                 PlaceTreesRandomly();
 419         }
 420 }
 421
 422 /**
 423  * Plant a tree.
 424  * @param tile end tile of area-drag
 425  * @param flags type of operation
 426  * @param p1 tree type, TREE_INVALID means random.
 427  * @param p2 start tile of area-drag of tree plantation
 428  * @param text unused
 429  * @return the cost of this operation or an error
 430  */
 431 CommandCost CmdPlantTree(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
 432 {
 433         StringID msg = INVALID_STRING_ID;
 434         CommandCost cost(EXPENSES_OTHER);
 435         const byte tree_to_plant = GB(p1, 0, 8); // We cannot use Extract as min and max are climate specific.
 436
 437         if (p2 >= MapSize()) return CMD_ERROR;
 438         /* Check the tree type within the current climate */
 439         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;
 440
 441         Company *c = (_game_mode != GM_EDITOR) ? Company::GetIfValid(_current_company) : NULL;
 442         int limit = (c == NULL ? INT32_MAX : GB(c->tree_limit, 16, 16));
 443
 444         TileArea ta(tile, p2);
 445         TILE_AREA_LOOP(tile, ta) {
 446                 switch (GetTileType(tile)) {
 447                         case MP_TREES:
 448                         {
 449                                 bool grow_existing_tree_instead = false;
 450
 451                                 /* no more space for trees? */
 452                                 if (_game_mode != GM_EDITOR && (GetTreeCount(tile) >= 4 || ((int)GetTreeCount(tile) >= (GetTileZ(tile) + (_settings_game.game_creation.landscape != LT_TROPIC ? 0 : 1))))) {
 453                                         if (GetTreeGrowth(tile) < 3) {
 454                                                 grow_existing_tree_instead = true;
 455                                         } else {
 456                                                 msg = STR_ERROR_TREE_ALREADY_HERE;
 457                                                 continue;
 458                                         }
 459                                 }
 460
 461                                 /* Thin out trees along the tree line range */
 462                                 uint tree_line_range = _settings_game.construction.trees_around_snow_line_range;
 463                                 uint min_tree_line_height = _settings_game.game_creation.tree_line_height - tree_line_range;
 464                                 uint height_above_min_tree_line = max(0u, GetTileZ(tile) - min_tree_line_height);
 465                                 uint percent_of_range = height_above_min_tree_line * 100u / tree_line_range;
 466                                 uint max_tree_count = 4u - ((4u * percent_of_range) / 100u);
 467
 468                                 if (GetTreeCount(tile) >= max_tree_count) {
 469                                         if (GetTreeGrowth(tile) < 3) {
 470                                                 grow_existing_tree_instead = true;
 471                                         }
 472                                         else {
 473                                                 msg = STR_ERROR_TREE_PLANT_LIMIT_REACHED;
 474                                                 continue;
 475                                         }
 476                                 }
 477
 478                                 /* Test tree limit. */
 479                                 if (--limit < 1) {
 480                                         msg = STR_ERROR_TREE_PLANT_LIMIT_REACHED;
 481                                         break;
 482                                 }
 483
 484                                 if (flags & DC_EXEC) {
 485                                         if (grow_existing_tree_instead) {
 486                                                 SetTreeGrowth(tile, 3);
 487                                         } else {
 488                                                 AddTreeCount(tile, 1);
 489                                         }
 490                                         MarkTileDirtyByTile(tile, ZOOM_LVL_DRAW_MAP);
 491                                         if (c != NULL) c->tree_limit -= 1 << 16;
 492                                 }
 493                                 /* 2x as expensive to add more trees to an existing tile */
 494                                 cost.AddCost(_price[PR_BUILD_TREES] * 2);
 495                                 break;
 496                         }
 497
 498                         case MP_WATER:
 499                                 if (!CanPlantTreesOnTile(tile, false) || !IsCoast(tile) || IsSlopeWithOneCornerRaised(GetTileSlope(tile))) {
 500                                         msg = STR_ERROR_CAN_T_BUILD_ON_WATER;
 501                                         continue;
 502                                 }
 503                                 FALLTHROUGH;
 504
 505                         case MP_CLEAR: {
 506                                 if (!CanPlantTreesOnTile(tile, false) || IsBridgeAbove(tile)) {
 507                                         msg = STR_ERROR_SITE_UNSUITABLE;
 508                                         continue;
 509                                 }
 510
 511                                 TreeType treetype = (TreeType)tree_to_plant;
 512                                 /* Be a bit picky about which trees go where. */
 513                                 if (_settings_game.game_creation.landscape == LT_TROPIC && treetype != TREE_INVALID && (
 514                                                 /* No cacti outside the desert */
 515                                                 (treetype == TREE_CACTUS && GetTropicZone(tile) != TROPICZONE_DESERT) ||
 516                                                 /* No rain forest trees outside the rain forest, except in the editor mode where it makes those tiles rain forest tile */
 517                                                 (IsInsideMM(treetype, TREE_RAINFOREST, TREE_CACTUS) && GetTropicZone(tile) != TROPICZONE_RAINFOREST && _game_mode != GM_EDITOR) ||
 518                                                 /* And no subtropical trees in the desert/rain forest */
 519                                                 (IsInsideMM(treetype, TREE_SUB_TROPICAL, TREE_TOYLAND) && GetTropicZone(tile) != TROPICZONE_NORMAL))) {
 520                                         msg = STR_ERROR_TREE_WRONG_TERRAIN_FOR_TREE_TYPE;
 521                                         continue;
 522                                 }
 523
 524                                 /* Test tree limit. */
 525                                 if (--limit < 1) {
 526                                         msg = STR_ERROR_TREE_PLANT_LIMIT_REACHED;
 527                                         break;
 528                                 }
 529
 530                                 if (IsTileType(tile, MP_CLEAR)) {
 531                                         /* Remove fields or rocks. Note that the ground will get barrened */
 532                                         switch (GetRawClearGround(tile)) {
 533                                                 case CLEAR_FIELDS:
 534                                                 case CLEAR_ROCKS: {
 535                                                         CommandCost ret = DoCommand(tile, 0, 0, flags, CMD_LANDSCAPE_CLEAR);
 536                                                         if (ret.Failed()) return ret;
 537                                                         cost.AddCost(ret);
 538                                                         break;
 539                                                 }
 540
 541                                                 default: break;
 542                                         }
 543                                 }
 544
 545                                 if (_game_mode != GM_EDITOR && Company::IsValidID(_current_company)) {
 546                                         Town *t = ClosestTownFromTile(tile, _settings_game.economy.dist_local_authority);
 547                                         if (t != NULL) ChangeTownRating(t, RATING_TREE_UP_STEP, RATING_TREE_MAXIMUM, flags);
 548                                 }
 549
 550                                 if (flags & DC_EXEC) {
 551                                         if (treetype == TREE_INVALID) {
 552                                                 treetype = GetRandomTreeType(tile, GB(Random(), 24, 8));
 553
 554                                                 if (treetype == TREE_INVALID) {
 555                                                         if (_settings_game.construction.trees_around_snow_line_enabled && _settings_game.game_creation.landscape != LT_TROPIC) {
 556                                                                 if (GetTileZ(tile) <= HighestSnowLine()) {
 557                                                                         treetype = (TreeType)(GB(Random(), 24, 8) * TREE_COUNT_TEMPERATE / 256 + TREE_TEMPERATE);
 558                                                                 }
 559                                                                 else {
 560                                                                         treetype = (TreeType)(GB(Random(), 24, 8) * TREE_COUNT_SUB_ARCTIC / 256 + TREE_SUB_ARCTIC);
 561                                                                 }
 562                                                         }
 563                                                         else {
 564                                                                 treetype = TREE_CACTUS;
 565                                                         }
 566                                                 }
 567                                         }
 568
 569                                         /* Plant full grown trees in scenario editor */
 570                                         PlantTreesOnTile(tile, treetype, 0, _game_mode == GM_EDITOR ? 3 : 0);
 571                                         MarkTileDirtyByTile(tile, ZOOM_LVL_DRAW_MAP);
 572                                         if (c != NULL) c->tree_limit -= 1 << 16;
 573
 574                                         /* When planting rainforest-trees, set tropiczone to rainforest in editor. */
 575                                         if (_game_mode == GM_EDITOR && IsInsideMM(treetype, TREE_RAINFOREST, TREE_CACTUS)) {
 576                                                 SetTropicZone(tile, TROPICZONE_RAINFOREST);
 577                                         }
 578                                 }
 579                                 cost.AddCost(_price[PR_BUILD_TREES]);
 580                                 break;
 581                         }
 582
 583                         default:
 584                                 msg = STR_ERROR_SITE_UNSUITABLE;
 585                                 break;
 586                 }
 587
 588                 /* Tree limit used up? No need to check more. */
 589                 if (limit < 0) break;
 590         }
 591
 592         if (cost.GetCost() == 0) {
 593                 return_cmd_error(msg);
 594         } else {
 595                 return cost;
 596         }
 597 }
 598
 599 struct TreeListEnt : PalSpriteID {
 600         byte x, y;
 601 };
 602
 603 static void DrawTile_Trees(TileInfo *ti)
 604 {
 605         switch (GetTreeGround(ti->tile)) {
 606                 case TREE_GROUND_SHORE: DrawShoreTile(ti->tileh); break;
 607                 case TREE_GROUND_GRASS: DrawClearLandTile(ti, GetTreeDensity(ti->tile)); break;
 608                 case TREE_GROUND_ROUGH: DrawHillyLandTile(ti); break;
 609                 default: DrawGroundSprite(_clear_land_sprites_snow_desert[GetTreeDensity(ti->tile)] + SlopeToSpriteOffset(ti->tileh), PAL_NONE); break;
 610         }
 611
 612         DrawOverlay(ti, MP_TREES);
 613
 614         /* Do not draw trees when the invisible trees setting is set */
 615         if (IsInvisibilitySet(TO_TREES)) return;
 616
 617         uint tmp = CountBits(ti->tile + ti->x + ti->y);
 618         uint index = GB(tmp, 0, 2) + (GetTreeType(ti->tile) << 2);
 619
 620         /* different tree styles above one of the grounds */
 621         if ((GetTreeGround(ti->tile) == TREE_GROUND_SNOW_DESERT || GetTreeGround(ti->tile) == TREE_GROUND_ROUGH_SNOW) &&
 622                         GetTreeDensity(ti->tile) >= 2 &&
 623                         IsInsideMM(index, TREE_SUB_ARCTIC << 2, TREE_RAINFOREST << 2)) {
 624                 index += 164 - (TREE_SUB_ARCTIC << 2);
 625         }
 626
 627         assert(index < lengthof(_tree_layout_sprite));
 628
 629         const PalSpriteID *s = _tree_layout_sprite[index];
 630         const TreePos *d = _tree_layout_xy[GB(tmp, 2, 2)];
 631
 632         /* combine trees into one sprite object */
 633         StartSpriteCombine();
 634
 635         TreeListEnt te[4];
 636
 637         /* put the trees to draw in a list */
 638         uint trees = GetTreeCount(ti->tile);
 639
 640         for (uint i = 0; i < trees; i++) {
 641                 SpriteID sprite = s[0].sprite + (i == trees - 1 ? GetTreeGrowth(ti->tile) : 3);
 642                 PaletteID pal = s[0].pal;
 643
 644                 te[i].sprite = sprite;
 645                 te[i].pal    = pal;
 646                 te[i].x = d->x;
 647                 te[i].y = d->y;
 648                 s++;
 649                 d++;
 650         }
 651
 652         /* draw them in a sorted way */
 653         int z = ti->z + GetSlopeMaxPixelZ(ti->tileh) / 2;
 654
 655         for (; trees > 0; trees--) {
 656                 uint min = te[0].x + te[0].y;
 657                 uint mi = 0;
 658
 659                 for (uint i = 1; i < trees; i++) {
 660                         if ((uint)(te[i].x + te[i].y) < min) {
 661                                 min = te[i].x + te[i].y;
 662                                 mi = i;
 663                         }
 664                 }
 665
 666                 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);
 667
 668                 /* replace the removed one with the last one */
 669                 te[mi] = te[trees - 1];
 670         }
 671
 672         EndSpriteCombine();
 673 }
 674
 675
 676 static int GetSlopePixelZ_Trees(TileIndex tile, uint x, uint y)
 677 {
 678         int z;
 679         Slope tileh = GetTilePixelSlope(tile, &z);
 680
 681         return z + GetPartialPixelZ(x & 0xF, y & 0xF, tileh);
 682 }
 683
 684 static Foundation GetFoundation_Trees(TileIndex tile, Slope tileh)
 685 {
 686         return FOUNDATION_NONE;
 687 }
 688
 689 static CommandCost ClearTile_Trees(TileIndex tile, DoCommandFlag flags)
 690 {
 691         uint num;
 692
 693         if (Company::IsValidID(_current_company)) {
 694                 Town *t = ClosestTownFromTile(tile, _settings_game.economy.dist_local_authority);
 695                 if (t != NULL) ChangeTownRating(t, RATING_TREE_DOWN_STEP, RATING_TREE_MINIMUM, flags);
 696         }
 697
 698         num = GetTreeCount(tile);
 699         if (IsInsideMM(GetTreeType(tile), TREE_RAINFOREST, TREE_CACTUS)) num *= 4;
 700
 701         if (flags & DC_EXEC) DoClearSquare(tile);
 702
 703         return CommandCost(EXPENSES_CONSTRUCTION, num * _price[PR_CLEAR_TREES]);
 704 }
 705
 706 static void GetTileDesc_Trees(TileIndex tile, TileDesc *td)
 707 {
 708         TreeType tt = GetTreeType(tile);
 709
 710         if (IsInsideMM(tt, TREE_RAINFOREST, TREE_CACTUS)) {
 711                 td->str = STR_LAI_TREE_NAME_RAINFOREST;
 712         } else {
 713                 td->str = tt == TREE_CACTUS ? STR_LAI_TREE_NAME_CACTUS_PLANTS : STR_LAI_TREE_NAME_TREES;
 714         }
 715
 716         td->owner[0] = GetTileOwner(tile);
 717 }
 718
 719 static void TileLoopTreesDesert(TileIndex tile)
 720 {
 721         switch (GetTropicZone(tile)) {
 722                 case TROPICZONE_DESERT:
 723                         if (GetTreeGround(tile) != TREE_GROUND_SNOW_DESERT) {
 724                                 SetTreeGroundDensity(tile, TREE_GROUND_SNOW_DESERT, 3);
 725                                 MarkTileDirtyByTile(tile, ZOOM_LVL_DRAW_MAP);
 726                         }
 727                         break;
 728
 729                 case TROPICZONE_RAINFOREST: {
 730                         static const SoundFx forest_sounds[] = {
 731                                 SND_42_LOON_BIRD,
 732                                 SND_43_LION,
 733                                 SND_44_MONKEYS,
 734                                 SND_48_DISTANT_BIRD
 735                         };
 736                         uint32 r = Random();
 737
 738                         if (Chance16I(1, 200, r) && _settings_client.sound.ambient) SndPlayTileFx(forest_sounds[GB(r, 16, 2)], tile);
 739                         break;
 740                 }
 741
 742                 default: break;
 743         }
 744 }
 745
 746 static void TileLoopTreesAlps(TileIndex tile)
 747 {
 748         int k = GetTileZ(tile) - GetSnowLine() + 1;
 749
 750         if (k < 0) {
 751                 switch (GetTreeGround(tile)) {
 752                         case TREE_GROUND_SNOW_DESERT: SetTreeGroundDensity(tile, TREE_GROUND_GRASS, 3); break;
 753                         case TREE_GROUND_ROUGH_SNOW:  SetTreeGroundDensity(tile, TREE_GROUND_ROUGH, 3); break;
 754                         default: return;
 755                 }
 756         } else {
 757                 uint density = min<uint>(k, 3);
 758
 759                 if (GetTreeGround(tile) != TREE_GROUND_SNOW_DESERT && GetTreeGround(tile) != TREE_GROUND_ROUGH_SNOW) {
 760                         TreeGround tg = GetTreeGround(tile) == TREE_GROUND_ROUGH ? TREE_GROUND_ROUGH_SNOW : TREE_GROUND_SNOW_DESERT;
 761                         SetTreeGroundDensity(tile, tg, density);
 762                 } else if (GetTreeDensity(tile) != density) {
 763                         SetTreeGroundDensity(tile, GetTreeGround(tile), density);
 764                 } else {
 765                         if (GetTreeDensity(tile) == 3) {
 766                                 uint32 r = Random();
 767                                 if (Chance16I(1, 200, r) && _settings_client.sound.ambient) {
 768                                         SndPlayTileFx((r & 0x80000000) ? SND_39_HEAVY_WIND : SND_34_WIND, tile);
 769                                 }
 770                         }
 771                         return;
 772                 }
 773         }
 774         MarkTileDirtyByTile(tile, ZOOM_LVL_DRAW_MAP);
 775 }
 776
 777 static void TileLoop_Trees(TileIndex tile)
 778 {
 779         if (GetTreeGround(tile) == TREE_GROUND_SHORE) {
 780                 TileLoop_Water(tile);
 781         } else {
 782                 switch (_settings_game.game_creation.landscape) {
 783                         case LT_TROPIC: TileLoopTreesDesert(tile); break;
 784                         case LT_ARCTIC: TileLoopTreesAlps(tile);   break;
 785                 }
 786         }
 787
 788         AmbientSoundEffect(tile);
 789
 790         uint treeCounter = GetTreeCounter(tile);
 791
 792         /* Handle growth of grass (under trees/on MP_TREES tiles) at every 8th processings, like it's done for grass on MP_CLEAR tiles. */
 793         if ((treeCounter & 7) == 7 && GetTreeGround(tile) == TREE_GROUND_GRASS) {
 794                 uint density = GetTreeDensity(tile);
 795                 if (density < 3) {
 796                         SetTreeGroundDensity(tile, TREE_GROUND_GRASS, density + 1);
 797                         MarkTileDirtyByTile(tile, ZOOM_LVL_DRAW_MAP);
 798                 }
 799         }
 800
 801         if (GetTreeCounter(tile) < 15) {
 802                 AddTreeCounter(tile, 1);
 803                 return;
 804         }
 805
 806         SetTreeCounter(tile, 0);
 807
 808         if (_settings_game.construction.tree_growth_rate > 0) {
 809                 /* Nature randomness */
 810                 uint8 grow_slowing_values[3] = { 5, 20, 120 }; // slow, very slow, extremely slow
 811                 uint16 prob = 0x10000 / grow_slowing_values[_settings_game.construction.tree_growth_rate - 1];
 812                 if (GB(Random(), 0, 16) >= (prob / 15)) {
 813                         return;
 814                 }
 815         }
 816
 817         switch (GetTreeGrowth(tile)) {
 818                 case 3: // regular sized tree
 819                         if (_settings_game.game_creation.landscape == LT_TROPIC &&
 820                                         GetTreeType(tile) != TREE_CACTUS &&
 821                                         GetTropicZone(tile) == TROPICZONE_DESERT) {
 822                                 AddTreeGrowth(tile, 1);
 823                         } else {
 824                                 switch (GB(Random(), 0, 3)) {
 825                                         case 0: // start destructing
 826                                                 AddTreeGrowth(tile, 1);
 827                                                 break;
 828
 829                                         case 1: // add a tree
 830                                         {
 831                                                 int tree_line_range = _settings_game.construction.trees_around_snow_line_range;
 832                                                 int min_tree_line_height = _settings_game.game_creation.tree_line_height - tree_line_range;
 833                                                 bool treeline_treecount_exceeded = false;
 834
 835                                                 if (GetTileZ(tile) >= min_tree_line_height) {
 836                                                         // Slowly thin out trees.
 837                                                         int height_above_min_tree_line = max(0, GetTileZ(tile) - min_tree_line_height);
 838                                                         int percent_of_range = 100 - (height_above_min_tree_line * 100 / tree_line_range);
 839
 840                                                         uint allowed_tree_count = (4u * percent_of_range) / 100u;
 841
 842                                                         treeline_treecount_exceeded = GetTreeCount(tile) >= allowed_tree_count;
 843                                                 }
 844
 845                                                 if ((GetTreeCount(tile) < 4) && (GetTreeType(tile) != TREE_CACTUS) && !treeline_treecount_exceeded && ((int)GetTreeCount(tile) < (GetTileZ(tile) + (_settings_game.game_creation.landscape != LT_TROPIC ? 0 : 1)))) {
 846                                                         AddTreeCount(tile, 1);
 847                                                         SetTreeGrowth(tile, 0);
 848                                                 }
 849                                         }
 850                                         FALLTHROUGH;
 851
 852                                         case 2: { // add a neighbouring tree
 853                                                 /* Don't plant extra trees if that's not allowed. */
 854                                                 if ((_settings_game.game_creation.landscape == LT_TROPIC && GetTropicZone(tile) == TROPICZONE_RAINFOREST) ?
 855                                                                 _settings_game.construction.extra_tree_placement == ETP_NONE :
 856                                                                 _settings_game.construction.extra_tree_placement != ETP_ALL) {
 857                                                         break;
 858                                                 }
 859
 860                                                 if ((_settings_game.game_creation.landscape != LT_TROPIC && GetTileZ(tile) < 3) || (GetTreeType(tile) == TREE_CACTUS))
 861                                                 {
 862                                                         uint32 r = Random();
 863                                                         int x = GB(r, 0, 5) - 16;
 864                                                         int y = GB(r, 8, 5) - 16;
 865                                                         TileIndex cur_tile = TileAddWrap(tile, x, y);
 866
 867                                                         if (cur_tile == INVALID_TILE) return;
 868
 869                                                         /* Keep in range of the existing tree */
 870                                                         if (abs(x) + abs(y) > 16) return;
 871
 872                                                         /* Clear tile, no farm-tiles or rocks */
 873                                                         if (!CanPlantTreesOnTile(cur_tile, true)) return;
 874
 875                                                         /* Not too much height difference */
 876                                                         if (Delta(GetTileZ(cur_tile), GetTileZ(tile)) > 2) return;
 877
 878                                                         /* Place one tree and quit */
 879                                                         PlantTreesOnTile(cur_tile, GetTreeType(tile), 0, 0);
 880                                                         break;
 881                                                 }
 882                                                 else
 883                                                 {
 884                                                         TreeType treetype = GetTreeType(tile);
 885
 886                                                         tile += TileOffsByDir((Direction)(Random() & 7));
 887
 888                                                         /* Cacti don't spread */
 889                                                         if (!CanPlantTreesOnTile(tile, true)) return;
 890
 891                                                         /* Don't plant trees, if ground was freshly cleared */
 892                                                         if (IsTileType(tile, MP_CLEAR) && GetClearGround(tile) == CLEAR_GRASS && GetClearDensity(tile) != 3) return;
 893
 894                                                         PlantTreesOnTile(tile, treetype, 0, 0);
 895                                                 }
 896                                                 break;
 897                                         }
 898
 899                                         default:
 900                                                 return;
 901                                 }
 902                         }
 903                         break;
 904
 905                 case 6: // final stage of tree destruction
 906                         if (GetTreeCount(tile) > 1) {
 907                                 /* more than one tree, delete it */
 908                                 AddTreeCount(tile, -1);
 909                                 SetTreeGrowth(tile, 3);
 910                         } else {
 911                                 /* just one tree, change type into MP_CLEAR */
 912                                 switch (GetTreeGround(tile)) {
 913                                         case TREE_GROUND_SHORE: MakeShore(tile); break;
 914                                         case TREE_GROUND_GRASS: MakeClear(tile, CLEAR_GRASS, GetTreeDensity(tile)); break;
 915                                         case TREE_GROUND_ROUGH: MakeClear(tile, CLEAR_ROUGH, 3); break;
 916                                         case TREE_GROUND_ROUGH_SNOW: {
 917                                                 uint density = GetTreeDensity(tile);
 918                                                 MakeClear(tile, CLEAR_ROUGH, 3);
 919                                                 MakeSnow(tile, density);
 920                                                 break;
 921                                         }
 922                                         default: // snow or desert
 923                                                 if (_settings_game.game_creation.landscape == LT_TROPIC) {
 924                                                         MakeClear(tile, CLEAR_DESERT, GetTreeDensity(tile));
 925                                                 } else {
 926                                                         uint density = GetTreeDensity(tile);
 927                                                         MakeClear(tile, CLEAR_GRASS, 3);
 928                                                         MakeSnow(tile, density);
 929                                                 }
 930                                                 break;
 931                                 }
 932                         }
 933                         break;
 934
 935                 default:
 936                         AddTreeGrowth(tile, 1);
 937                         break;
 938         }
 939
 940         MarkTileDirtyByTile(tile, ZOOM_LVL_DRAW_MAP);
 941 }
 942
 943 void OnTick_Trees()
 944 {
 945         /* Don't place trees if that's not allowed */
 946         if (_settings_game.construction.extra_tree_placement == ETP_NONE) return;
 947
 948         uint32 r;
 949         TileIndex tile;
 950         TreeType tree;
 951
 952         /* place a tree at a random rainforest spot */
 953         if (_settings_game.game_creation.landscape == LT_TROPIC &&
 954                         (r = Random(), tile = RandomTileSeed(r), GetTropicZone(tile) == TROPICZONE_RAINFOREST) &&
 955                         CanPlantTreesOnTile(tile, false) &&
 956                         (tree = GetRandomTreeType(tile, GB(r, 24, 8))) != TREE_INVALID) {
 957                 PlantTreesOnTile(tile, tree, 0, 0);
 958         }
 959
 960         /* byte underflow */
 961         if (--_trees_tick_ctr != 0 || _settings_game.construction.extra_tree_placement != ETP_ALL) return;
 962
 963         /* place a tree at a random spot */
 964         r = Random();
 965         tile = RandomTileSeed(r);
 966         if (CanPlantTreesOnTile(tile, false) && (tree = GetRandomTreeType(tile, GB(r, 24, 8))) != TREE_INVALID) {
 967                 PlantTreesOnTile(tile, tree, 0, 0);
 968         }
 969 }
 970
 971 static TrackStatus GetTileTrackStatus_Trees(TileIndex tile, TransportType mode, uint sub_mode, DiagDirection side)
 972 {
 973         return 0;
 974 }
 975
 976 static void ChangeTileOwner_Trees(TileIndex tile, Owner old_owner, Owner new_owner)
 977 {
 978         /* not used */
 979 }
 980
 981 void InitializeTrees()
 982 {
 983         _trees_tick_ctr = 0;
 984 }
 985
 986 static CommandCost TerraformTile_Trees(TileIndex tile, DoCommandFlag flags, int z_new, Slope tileh_new)
 987 {
 988         return DoCommand(tile, 0, 0, flags, CMD_LANDSCAPE_CLEAR);
 989 }
 990
 991
 992 extern const TileTypeProcs _tile_type_trees_procs = {
 993         DrawTile_Trees,           // draw_tile_proc
 994         GetSlopePixelZ_Trees,     // get_slope_z_proc
 995         ClearTile_Trees,          // clear_tile_proc
 996         NULL,                     // add_accepted_cargo_proc
 997         GetTileDesc_Trees,        // get_tile_desc_proc
 998         GetTileTrackStatus_Trees, // get_tile_track_status_proc
 999         NULL,                     // click_tile_proc
1000         NULL,                     // animate_tile_proc
1001         TileLoop_Trees,           // tile_loop_proc
1002         ChangeTileOwner_Trees,    // change_tile_owner_proc
1003         NULL,                     // add_produced_cargo_proc
1004         NULL,                     // vehicle_enter_tile_proc
1005         GetFoundation_Trees,      // get_foundation_proc
1006         TerraformTile_Trees,      // terraform_tile_proc
1007 };