src/terraform_cmd.cpp

   1 /*
   2  * This file is part of OpenTTD.
   3  * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
   4  * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
   5  * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
   6  */
   7
   8 /** @file terraform_cmd.cpp Commands related to terraforming. */
   9
  10 #include "stdafx.h"
  11 #include "command_func.h"
  12 #include "tunnel_map.h"
  13 #include "bridge_map.h"
  14 #include "viewport_func.h"
  15 #include "genworld.h"
  16 #include "object_base.h"
  17 #include "company_base.h"
  18 #include "company_func.h"
  19
  20 #include "table/strings.h"
  21
  22 #include <map>
  23 #include <set>
  24
  25 #include "safeguards.h"
  26
  27 /** Set of tiles. */
  28 typedef std::set<TileIndex> TileIndexSet;
  29 /** Mapping of tiles to their height. */
  30 typedef std::map<TileIndex, int> TileIndexToHeightMap;
  31
  32 /** State of the terraforming. */
  33 struct TerraformerState {
  34         TileIndexSet dirty_tiles;                ///< The tiles that need to be redrawn.
  35         TileIndexToHeightMap tile_to_new_height; ///< The tiles for which the height has changed.
  36 };
  37
  38 TileIndex _terraform_err_tile; ///< first tile we couldn't terraform
  39
  40 /**
  41  * Gets the TileHeight (height of north corner) of a tile as of current terraforming progress.
  42  *
  43  * @param ts TerraformerState.
  44  * @param tile Tile.
  45  * @return TileHeight.
  46  */
  47 static int TerraformGetHeightOfTile(const TerraformerState *ts, TileIndex tile)
  48 {
  49         TileIndexToHeightMap::const_iterator it = ts->tile_to_new_height.find(tile);
  50         return it != ts->tile_to_new_height.end() ? it->second : TileHeight(tile);
  51 }
  52
  53 /**
  54  * Stores the TileHeight (height of north corner) of a tile in a TerraformerState.
  55  *
  56  * @param ts TerraformerState.
  57  * @param tile Tile.
  58  * @param height New TileHeight.
  59  */
  60 static void TerraformSetHeightOfTile(TerraformerState *ts, TileIndex tile, int height)
  61 {
  62         ts->tile_to_new_height[tile] = height;
  63 }
  64
  65 /**
  66  * Adds a tile to the "tile_table" in a TerraformerState.
  67  *
  68  * @param ts TerraformerState.
  69  * @param tile Tile.
  70  * @ingroup dirty
  71  */
  72 static void TerraformAddDirtyTile(TerraformerState *ts, TileIndex tile)
  73 {
  74         ts->dirty_tiles.insert(tile);
  75 }
  76
  77 /**
  78  * Adds all tiles that incident with the north corner of a specific tile to the "tile_table" in a TerraformerState.
  79  *
  80  * @param ts TerraformerState.
  81  * @param tile Tile.
  82  * @ingroup dirty
  83  */
  84 static void TerraformAddDirtyTileAround(TerraformerState *ts, TileIndex tile)
  85 {
  86         /* Make sure all tiles passed to TerraformAddDirtyTile are within [0, MapSize()] */
  87         if (TileY(tile) >= 1) TerraformAddDirtyTile(ts, tile + TileDiffXY( 0, -1));
  88         if (TileY(tile) >= 1 && TileX(tile) >= 1) TerraformAddDirtyTile(ts, tile + TileDiffXY(-1, -1));
  89         if (TileX(tile) >= 1) TerraformAddDirtyTile(ts, tile + TileDiffXY(-1,  0));
  90         TerraformAddDirtyTile(ts, tile);
  91 }
  92
  93 /**
  94  * Terraform the north corner of a tile to a specific height.
  95  *
  96  * @param ts TerraformerState.
  97  * @param tile Tile.
  98  * @param height Aimed height.
  99  * @return Error code or cost.
 100  */
 101 static CommandCost TerraformTileHeight(TerraformerState *ts, TileIndex tile, int height)
 102 {
 103         assert(tile < MapSize());
 104
 105         /* Check range of destination height */
 106         if (height < 0) return_cmd_error(STR_ERROR_ALREADY_AT_SEA_LEVEL);
 107         if (height > _settings_game.construction.max_heightlevel) return_cmd_error(STR_ERROR_TOO_HIGH);
 108
 109         /*
 110          * Check if the terraforming has any effect.
 111          * This can only be true, if multiple corners of the start-tile are terraformed (i.e. the terraforming is done by towns/industries etc.).
 112          * In this case the terraforming should fail. (Don't know why.)
 113          */
 114         if (height == TerraformGetHeightOfTile(ts, tile)) return CMD_ERROR;
 115
 116         /* Check "too close to edge of map". Only possible when freeform-edges is off. */
 117         uint x = TileX(tile);
 118         uint y = TileY(tile);
 119         if (!_settings_game.construction.freeform_edges && ((x <= 1) || (y <= 1) || (x >= MapMaxX() - 1) || (y >= MapMaxY() - 1))) {
 120                 /*
 121                  * Determine a sensible error tile
 122                  */
 123                 if (x == 1) x = 0;
 124                 if (y == 1) y = 0;
 125                 _terraform_err_tile = TileXY(x, y);
 126                 return_cmd_error(STR_ERROR_TOO_CLOSE_TO_EDGE_OF_MAP);
 127         }
 128
 129         /* Mark incident tiles that are involved in the terraforming. */
 130         TerraformAddDirtyTileAround(ts, tile);
 131
 132         /* Store the height modification */
 133         TerraformSetHeightOfTile(ts, tile, height);
 134
 135         CommandCost total_cost(EXPENSES_CONSTRUCTION);
 136
 137         /* Increment cost */
 138         total_cost.AddCost(_price[PR_TERRAFORM]);
 139
 140         /* Recurse to neighboured corners if height difference is larger than 1 */
 141         {
 142                 const TileIndexDiffC *ttm;
 143
 144                 TileIndex orig_tile = tile;
 145                 static const TileIndexDiffC _terraform_tilepos[] = {
 146                         { 1,  0}, // move to tile in SE
 147                         {-2,  0}, // undo last move, and move to tile in NW
 148                         { 1,  1}, // undo last move, and move to tile in SW
 149                         { 0, -2}  // undo last move, and move to tile in NE
 150                 };
 151
 152                 for (ttm = _terraform_tilepos; ttm != endof(_terraform_tilepos); ttm++) {
 153                         tile += ToTileIndexDiff(*ttm);
 154
 155                         if (tile >= MapSize()) continue;
 156                         /* Make sure we don't wrap around the map */
 157                         if (Delta(TileX(orig_tile), TileX(tile)) == MapSizeX() - 1) continue;
 158                         if (Delta(TileY(orig_tile), TileY(tile)) == MapSizeY() - 1) continue;
 159
 160                         /* Get TileHeight of neighboured tile as of current terraform progress */
 161                         int r = TerraformGetHeightOfTile(ts, tile);
 162                         int height_diff = height - r;
 163
 164                         /* Is the height difference to the neighboured corner greater than 1? */
 165                         if (abs(height_diff) > 1) {
 166                                 /* Terraform the neighboured corner. The resulting height difference should be 1. */
 167                                 height_diff += (height_diff < 0 ? 1 : -1);
 168                                 CommandCost cost = TerraformTileHeight(ts, tile, r + height_diff);
 169                                 if (cost.Failed()) return cost;
 170                                 total_cost.AddCost(cost);
 171                         }
 172                 }
 173         }
 174
 175         return total_cost;
 176 }
 177
 178 /**
 179  * Terraform land
 180  * @param tile tile to terraform
 181  * @param flags for this command type
 182  * @param p1 corners to terraform (SLOPE_xxx)
 183  * @param p2 direction; eg up (non-zero) or down (zero)
 184  * @param text unused
 185  * @return the cost of this operation or an error
 186  */
 187 CommandCost CmdTerraformLand(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
 188 {
 189         _terraform_err_tile = INVALID_TILE;
 190
 191         CommandCost total_cost(EXPENSES_CONSTRUCTION);
 192         int direction = (p2 != 0 ? 1 : -1);
 193         TerraformerState ts;
 194
 195         /* Compute the costs and the terraforming result in a model of the landscape */
 196         if ((p1 & SLOPE_W) != 0 && tile + TileDiffXY(1, 0) < MapSize()) {
 197                 TileIndex t = tile + TileDiffXY(1, 0);
 198                 CommandCost cost = TerraformTileHeight(&ts, t, TileHeight(t) + direction);
 199                 if (cost.Failed()) return cost;
 200                 total_cost.AddCost(cost);
 201         }
 202
 203         if ((p1 & SLOPE_S) != 0 && tile + TileDiffXY(1, 1) < MapSize()) {
 204                 TileIndex t = tile + TileDiffXY(1, 1);
 205                 CommandCost cost = TerraformTileHeight(&ts, t, TileHeight(t) + direction);
 206                 if (cost.Failed()) return cost;
 207                 total_cost.AddCost(cost);
 208         }
 209
 210         if ((p1 & SLOPE_E) != 0 && tile + TileDiffXY(0, 1) < MapSize()) {
 211                 TileIndex t = tile + TileDiffXY(0, 1);
 212                 CommandCost cost = TerraformTileHeight(&ts, t, TileHeight(t) + direction);
 213                 if (cost.Failed()) return cost;
 214                 total_cost.AddCost(cost);
 215         }
 216
 217         if ((p1 & SLOPE_N) != 0) {
 218                 TileIndex t = tile + TileDiffXY(0, 0);
 219                 CommandCost cost = TerraformTileHeight(&ts, t, TileHeight(t) + direction);
 220                 if (cost.Failed()) return cost;
 221                 total_cost.AddCost(cost);
 222         }
 223
 224         /* Check if the terraforming is valid wrt. tunnels, bridges and objects on the surface
 225          * Pass == 0: Collect tileareas which are caused to be auto-cleared.
 226          * Pass == 1: Collect the actual cost. */
 227         for (int pass = 0; pass < 2; pass++) {
 228                 for (TileIndexSet::const_iterator it = ts.dirty_tiles.begin(); it != ts.dirty_tiles.end(); it++) {
 229                         TileIndex tile = *it;
 230
 231                         assert(tile < MapSize());
 232                         /* MP_VOID tiles can be terraformed but as tunnels and bridges
 233                          * cannot go under / over these tiles they don't need checking. */
 234                         if (IsTileType(tile, MP_VOID)) continue;
 235
 236                         /* Find new heights of tile corners */
 237                         int z_N = TerraformGetHeightOfTile(&ts, tile + TileDiffXY(0, 0));
 238                         int z_W = TerraformGetHeightOfTile(&ts, tile + TileDiffXY(1, 0));
 239                         int z_S = TerraformGetHeightOfTile(&ts, tile + TileDiffXY(1, 1));
 240                         int z_E = TerraformGetHeightOfTile(&ts, tile + TileDiffXY(0, 1));
 241
 242                         /* Find min and max height of tile */
 243                         int z_min = std::min({z_N, z_W, z_S, z_E});
 244                         int z_max = std::max({z_N, z_W, z_S, z_E});
 245
 246                         /* Compute tile slope */
 247                         Slope tileh = (z_max > z_min + 1 ? SLOPE_STEEP : SLOPE_FLAT);
 248                         if (z_W > z_min) tileh |= SLOPE_W;
 249                         if (z_S > z_min) tileh |= SLOPE_S;
 250                         if (z_E > z_min) tileh |= SLOPE_E;
 251                         if (z_N > z_min) tileh |= SLOPE_N;
 252
 253                         if (pass == 0) {
 254                                 /* Check if bridge would take damage */
 255                                 if (IsBridgeAbove(tile)) {
 256                                         int bridge_height = GetBridgeHeight(GetSouthernBridgeEnd(tile));
 257
 258                                         /* Check if bridge would take damage. */
 259                                         if (direction == 1 && bridge_height <= z_max) {
 260                                                 _terraform_err_tile = tile; // highlight the tile under the bridge
 261                                                 return_cmd_error(STR_ERROR_MUST_DEMOLISH_BRIDGE_FIRST);
 262                                         }
 263
 264                                         /* Is the bridge above not too high afterwards? */
 265                                         if (direction == -1 && bridge_height > (z_min + _settings_game.construction.max_bridge_height)) {
 266                                                 _terraform_err_tile = tile;
 267                                                 return_cmd_error(STR_ERROR_BRIDGE_TOO_HIGH_AFTER_LOWER_LAND);
 268                                         }
 269                                 }
 270                                 /* Check if tunnel would take damage */
 271                                 if (direction == -1 && IsTunnelInWay(tile, z_min)) {
 272                                         _terraform_err_tile = tile; // highlight the tile above the tunnel
 273                                         return_cmd_error(STR_ERROR_EXCAVATION_WOULD_DAMAGE);
 274                                 }
 275                         }
 276
 277                         /* Is the tile already cleared? */
 278                         const ClearedObjectArea *coa = FindClearedObject(tile);
 279                         bool indirectly_cleared = coa != nullptr && coa->first_tile != tile;
 280
 281                         /* Check tiletype-specific things, and add extra-cost */
 282                         const bool curr_gen = _generating_world;
 283                         if (_game_mode == GM_EDITOR) _generating_world = true; // used to create green terraformed land
 284                         DoCommandFlag tile_flags = flags | DC_AUTO | DC_FORCE_CLEAR_TILE;
 285                         if (pass == 0) {
 286                                 tile_flags &= ~DC_EXEC;
 287                                 tile_flags |= DC_NO_MODIFY_TOWN_RATING;
 288                         }
 289                         CommandCost cost;
 290                         if (indirectly_cleared) {
 291                                 cost = DoCommand(tile, 0, 0, tile_flags, CMD_LANDSCAPE_CLEAR);
 292                         } else {
 293                                 cost = _tile_type_procs[GetTileType(tile)]->terraform_tile_proc(tile, tile_flags, z_min, tileh);
 294                         }
 295                         _generating_world = curr_gen;
 296                         if (cost.Failed()) {
 297                                 _terraform_err_tile = tile;
 298                                 return cost;
 299                         }
 300                         if (pass == 1) total_cost.AddCost(cost);
 301                 }
 302         }
 303
 304         Company *c = Company::GetIfValid(_current_company);
 305         if (c != nullptr && GB(c->terraform_limit, 16, 16) < ts.tile_to_new_height.size()) {
 306                 return_cmd_error(STR_ERROR_TERRAFORM_LIMIT_REACHED);
 307         }
 308
 309         if (flags & DC_EXEC) {
 310                 /* Mark affected areas dirty. */
 311                 for (TileIndexSet::const_iterator it = ts.dirty_tiles.begin(); it != ts.dirty_tiles.end(); it++) {
 312                         MarkTileDirtyByTile(*it);
 313                         TileIndexToHeightMap::const_iterator new_height = ts.tile_to_new_height.find(tile);
 314                         if (new_height == ts.tile_to_new_height.end()) continue;
 315                         MarkTileDirtyByTile(*it, 0, new_height->second);
 316                 }
 317
 318                 /* change the height */
 319                 for (TileIndexToHeightMap::const_iterator it = ts.tile_to_new_height.begin();
 320                                 it != ts.tile_to_new_height.end(); it++) {
 321                         TileIndex tile = it->first;
 322                         int height = it->second;
 323
 324                         SetTileHeight(tile, (uint)height);
 325                 }
 326
 327                 if (c != nullptr) c->terraform_limit -= (uint32)ts.tile_to_new_height.size() << 16;
 328         }
 329         return total_cost;
 330 }
 331
 332
 333 /**
 334  * Levels a selected (rectangle) area of land
 335  * @param tile end tile of area-drag
 336  * @param flags for this command type
 337  * @param p1 start tile of area drag
 338  * @param p2 various bitstuffed data.
 339  *  bit      0: Whether to use the Orthogonal (0) or Diagonal (1) iterator.
 340  *  bits 1 - 2: Mode of leveling \c LevelMode.
 341  * @param text unused
 342  * @return the cost of this operation or an error
 343  */
 344 CommandCost CmdLevelLand(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
 345 {
 346         if (p1 >= MapSize()) return CMD_ERROR;
 347
 348         _terraform_err_tile = INVALID_TILE;
 349
 350         /* remember level height */
 351         uint oldh = TileHeight(p1);
 352
 353         /* compute new height */
 354         uint h = oldh;
 355         LevelMode lm = (LevelMode)GB(p2, 1, 2);
 356         switch (lm) {
 357                 case LM_LEVEL: break;
 358                 case LM_RAISE: h++; break;
 359                 case LM_LOWER: h--; break;
 360                 default: return CMD_ERROR;
 361         }
 362
 363         /* Check range of destination height */
 364         if (h > _settings_game.construction.max_heightlevel) return_cmd_error((oldh == 0) ? STR_ERROR_ALREADY_AT_SEA_LEVEL : STR_ERROR_TOO_HIGH);
 365
 366         Money money = GetAvailableMoneyForCommand();
 367         CommandCost cost(EXPENSES_CONSTRUCTION);
 368         CommandCost last_error(lm == LM_LEVEL ? STR_ERROR_ALREADY_LEVELLED : INVALID_STRING_ID);
 369         bool had_success = false;
 370
 371         const Company *c = Company::GetIfValid(_current_company);
 372         int limit = (c == nullptr ? INT32_MAX : GB(c->terraform_limit, 16, 16));
 373         if (limit == 0) return_cmd_error(STR_ERROR_TERRAFORM_LIMIT_REACHED);
 374
 375         TileIterator *iter = HasBit(p2, 0) ? (TileIterator *)new DiagonalTileIterator(tile, p1) : new OrthogonalTileIterator(tile, p1);
 376         for (; *iter != INVALID_TILE; ++(*iter)) {
 377                 TileIndex t = *iter;
 378                 uint curh = TileHeight(t);
 379                 while (curh != h) {
 380                         CommandCost ret = DoCommand(t, SLOPE_N, (curh > h) ? 0 : 1, flags & ~DC_EXEC, CMD_TERRAFORM_LAND);
 381                         if (ret.Failed()) {
 382                                 last_error = ret;
 383
 384                                 /* Did we reach the limit? */
 385                                 if (ret.GetErrorMessage() == STR_ERROR_TERRAFORM_LIMIT_REACHED) limit = 0;
 386                                 break;
 387                         }
 388
 389                         if (flags & DC_EXEC) {
 390                                 money -= ret.GetCost();
 391                                 if (money < 0) {
 392                                         _additional_cash_required = ret.GetCost();
 393                                         delete iter;
 394                                         return cost;
 395                                 }
 396                                 DoCommand(t, SLOPE_N, (curh > h) ? 0 : 1, flags, CMD_TERRAFORM_LAND);
 397                         } else {
 398                                 /* When we're at the terraform limit we better bail (unneeded) testing as well.
 399                                  * This will probably cause the terraforming cost to be underestimated, but only
 400                                  * when it's near the terraforming limit. Even then, the estimation is
 401                                  * completely off due to it basically counting terraforming double, so it being
 402                                  * cut off earlier might even give a better estimate in some cases. */
 403                                 if (--limit <= 0) {
 404                                         had_success = true;
 405                                         break;
 406                                 }
 407                         }
 408
 409                         cost.AddCost(ret);
 410                         curh += (curh > h) ? -1 : 1;
 411                         had_success = true;
 412                 }
 413
 414                 if (limit <= 0) break;
 415         }
 416
 417         delete iter;
 418         return had_success ? cost : last_error;
 419 }