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 #include "core/backup_type.hpp"
  20
  21 #include "table/strings.h"
  22
  23 #include <map>
  24 #include <set>
  25
  26 #include "safeguards.h"
  27
  28 /** Set of tiles. */
  29 typedef std::set<TileIndex> TileIndexSet;
  30 /** Mapping of tiles to their height. */
  31 typedef std::map<TileIndex, int> TileIndexToHeightMap;
  32
  33 /** State of the terraforming. */
  34 struct TerraformerState {
  35         TileIndexSet dirty_tiles;                ///< The tiles that need to be redrawn.
  36         TileIndexToHeightMap tile_to_new_height; ///< The tiles for which the height has changed.
  37 };
  38
  39 TileIndex _terraform_err_tile; ///< first tile we couldn't terraform
  40
  41 /**
  42  * Gets the TileHeight (height of north corner) of a tile as of current terraforming progress.
  43  *
  44  * @param ts TerraformerState.
  45  * @param tile Tile.
  46  * @return TileHeight.
  47  */
  48 static int TerraformGetHeightOfTile(const TerraformerState *ts, TileIndex tile)
  49 {
  50         TileIndexToHeightMap::const_iterator it = ts->tile_to_new_height.find(tile);
  51         return it != ts->tile_to_new_height.end() ? it->second : TileHeight(tile);
  52 }
  53
  54 /**
  55  * Stores the TileHeight (height of north corner) of a tile in a TerraformerState.
  56  *
  57  * @param ts TerraformerState.
  58  * @param tile Tile.
  59  * @param height New TileHeight.
  60  */
  61 static void TerraformSetHeightOfTile(TerraformerState *ts, TileIndex tile, int height)
  62 {
  63         ts->tile_to_new_height[tile] = height;
  64 }
  65
  66 /**
  67  * Adds a tile to the "tile_table" in a TerraformerState.
  68  *
  69  * @param ts TerraformerState.
  70  * @param tile Tile.
  71  * @ingroup dirty
  72  */
  73 static void TerraformAddDirtyTile(TerraformerState *ts, TileIndex tile)
  74 {
  75         ts->dirty_tiles.insert(tile);
  76 }
  77
  78 /**
  79  * Adds all tiles that incident with the north corner of a specific tile to the "tile_table" in a TerraformerState.
  80  *
  81  * @param ts TerraformerState.
  82  * @param tile Tile.
  83  * @ingroup dirty
  84  */
  85 static void TerraformAddDirtyTileAround(TerraformerState *ts, TileIndex tile)
  86 {
  87         /* Make sure all tiles passed to TerraformAddDirtyTile are within [0, MapSize()] */
  88         if (TileY(tile) >= 1) TerraformAddDirtyTile(ts, tile + TileDiffXY( 0, -1));
  89         if (TileY(tile) >= 1 && TileX(tile) >= 1) TerraformAddDirtyTile(ts, tile + TileDiffXY(-1, -1));
  90         if (TileX(tile) >= 1) TerraformAddDirtyTile(ts, tile + TileDiffXY(-1,  0));
  91         TerraformAddDirtyTile(ts, tile);
  92 }
  93
  94 /**
  95  * Terraform the north corner of a tile to a specific height.
  96  *
  97  * @param ts TerraformerState.
  98  * @param tile Tile.
  99  * @param height Aimed height.
 100  * @return Error code or cost.
 101  */
 102 static CommandCost TerraformTileHeight(TerraformerState *ts, TileIndex tile, int height)
 103 {
 104         assert(tile < MapSize());
 105
 106         /* Check range of destination height */
 107         if (height < 0) return_cmd_error(STR_ERROR_ALREADY_AT_SEA_LEVEL);
 108         if (height > _settings_game.construction.map_height_limit) return_cmd_error(STR_ERROR_TOO_HIGH);
 109
 110         /*
 111          * Check if the terraforming has any effect.
 112          * This can only be true, if multiple corners of the start-tile are terraformed (i.e. the terraforming is done by towns/industries etc.).
 113          * In this case the terraforming should fail. (Don't know why.)
 114          */
 115         if (height == TerraformGetHeightOfTile(ts, tile)) return CMD_ERROR;
 116
 117         /* Check "too close to edge of map". Only possible when freeform-edges is off. */
 118         uint x = TileX(tile);
 119         uint y = TileY(tile);
 120         if (!_settings_game.construction.freeform_edges && ((x <= 1) || (y <= 1) || (x >= MapMaxX() - 1) || (y >= MapMaxY() - 1))) {
 121                 /*
 122                  * Determine a sensible error tile
 123                  */
 124                 if (x == 1) x = 0;
 125                 if (y == 1) y = 0;
 126                 _terraform_err_tile = TileXY(x, y);
 127                 return_cmd_error(STR_ERROR_TOO_CLOSE_TO_EDGE_OF_MAP);
 128         }
 129
 130         /* Mark incident tiles that are involved in the terraforming. */
 131         TerraformAddDirtyTileAround(ts, tile);
 132
 133         /* Store the height modification */
 134         TerraformSetHeightOfTile(ts, tile, height);
 135
 136         CommandCost total_cost(EXPENSES_CONSTRUCTION);
 137
 138         /* Increment cost */
 139         total_cost.AddCost(_price[PR_TERRAFORM]);
 140
 141         /* Recurse to neighboured corners if height difference is larger than 1 */
 142         {
 143                 const TileIndexDiffC *ttm;
 144
 145                 TileIndex orig_tile = tile;
 146                 static const TileIndexDiffC _terraform_tilepos[] = {
 147                         { 1,  0}, // move to tile in SE
 148                         {-2,  0}, // undo last move, and move to tile in NW
 149                         { 1,  1}, // undo last move, and move to tile in SW
 150                         { 0, -2}  // undo last move, and move to tile in NE
 151                 };
 152
 153                 for (ttm = _terraform_tilepos; ttm != endof(_terraform_tilepos); ttm++) {
 154                         tile += ToTileIndexDiff(*ttm);
 155
 156                         if (tile >= MapSize()) continue;
 157                         /* Make sure we don't wrap around the map */
 158                         if (Delta(TileX(orig_tile), TileX(tile)) == MapSizeX() - 1) continue;
 159                         if (Delta(TileY(orig_tile), TileY(tile)) == MapSizeY() - 1) continue;
 160
 161                         /* Get TileHeight of neighboured tile as of current terraform progress */
 162                         int r = TerraformGetHeightOfTile(ts, tile);
 163                         int height_diff = height - r;
 164
 165                         /* Is the height difference to the neighboured corner greater than 1? */
 166                         if (abs(height_diff) > 1) {
 167                                 /* Terraform the neighboured corner. The resulting height difference should be 1. */
 168                                 height_diff += (height_diff < 0 ? 1 : -1);
 169                                 CommandCost cost = TerraformTileHeight(ts, tile, r + height_diff);
 170                                 if (cost.Failed()) return cost;
 171                                 total_cost.AddCost(cost);
 172                         }
 173                 }
 174         }
 175
 176         return total_cost;
 177 }
 178
 179 /**
 180  * Terraform land
 181  * @param tile tile to terraform
 182  * @param flags for this command type
 183  * @param p1 corners to terraform (SLOPE_xxx)
 184  * @param p2 direction; eg up (non-zero) or down (zero)
 185  * @param text unused
 186  * @return the cost of this operation or an error
 187  */
 188 CommandCost CmdTerraformLand(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const std::string &text)
 189 {
 190         _terraform_err_tile = INVALID_TILE;
 191
 192         CommandCost total_cost(EXPENSES_CONSTRUCTION);
 193         int direction = (p2 != 0 ? 1 : -1);
 194         TerraformerState ts;
 195
 196         /* Compute the costs and the terraforming result in a model of the landscape */
 197         if ((p1 & SLOPE_W) != 0 && tile + TileDiffXY(1, 0) < MapSize()) {
 198                 TileIndex t = tile + TileDiffXY(1, 0);
 199                 CommandCost cost = TerraformTileHeight(&ts, t, TileHeight(t) + direction);
 200                 if (cost.Failed()) return cost;
 201                 total_cost.AddCost(cost);
 202         }
 203
 204         if ((p1 & SLOPE_S) != 0 && tile + TileDiffXY(1, 1) < MapSize()) {
 205                 TileIndex t = tile + TileDiffXY(1, 1);
 206                 CommandCost cost = TerraformTileHeight(&ts, t, TileHeight(t) + direction);
 207                 if (cost.Failed()) return cost;
 208                 total_cost.AddCost(cost);
 209         }
 210
 211         if ((p1 & SLOPE_E) != 0 && tile + TileDiffXY(0, 1) < MapSize()) {
 212                 TileIndex t = tile + TileDiffXY(0, 1);
 213                 CommandCost cost = TerraformTileHeight(&ts, t, TileHeight(t) + direction);
 214                 if (cost.Failed()) return cost;
 215                 total_cost.AddCost(cost);
 216         }
 217
 218         if ((p1 & SLOPE_N) != 0) {
 219                 TileIndex t = tile + TileDiffXY(0, 0);
 220                 CommandCost cost = TerraformTileHeight(&ts, t, TileHeight(t) + direction);
 221                 if (cost.Failed()) return cost;
 222                 total_cost.AddCost(cost);
 223         }
 224
 225         /* Check if the terraforming is valid wrt. tunnels, bridges and objects on the surface
 226          * Pass == 0: Collect tileareas which are caused to be auto-cleared.
 227          * Pass == 1: Collect the actual cost. */
 228         for (int pass = 0; pass < 2; pass++) {
 229                 for (TileIndexSet::const_iterator it = ts.dirty_tiles.begin(); it != ts.dirty_tiles.end(); it++) {
 230                         TileIndex t = *it;
 231
 232                         assert(t < MapSize());
 233                         /* MP_VOID tiles can be terraformed but as tunnels and bridges
 234                          * cannot go under / over these tiles they don't need checking. */
 235                         if (IsTileType(t, MP_VOID)) continue;
 236
 237                         /* Find new heights of tile corners */
 238                         int z_N = TerraformGetHeightOfTile(&ts, t + TileDiffXY(0, 0));
 239                         int z_W = TerraformGetHeightOfTile(&ts, t + TileDiffXY(1, 0));
 240                         int z_S = TerraformGetHeightOfTile(&ts, t + TileDiffXY(1, 1));
 241                         int z_E = TerraformGetHeightOfTile(&ts, t + TileDiffXY(0, 1));
 242
 243                         /* Find min and max height of tile */
 244                         int z_min = std::min({z_N, z_W, z_S, z_E});
 245                         int z_max = std::max({z_N, z_W, z_S, z_E});
 246
 247                         /* Compute tile slope */
 248                         Slope tileh = (z_max > z_min + 1 ? SLOPE_STEEP : SLOPE_FLAT);
 249                         if (z_W > z_min) tileh |= SLOPE_W;
 250                         if (z_S > z_min) tileh |= SLOPE_S;
 251                         if (z_E > z_min) tileh |= SLOPE_E;
 252                         if (z_N > z_min) tileh |= SLOPE_N;
 253
 254                         if (pass == 0) {
 255                                 /* Check if bridge would take damage */
 256                                 if (IsBridgeAbove(t)) {
 257                                         int bridge_height = GetBridgeHeight(GetSouthernBridgeEnd(t));
 258
 259                                         /* Check if bridge would take damage. */
 260                                         if (direction == 1 && bridge_height <= z_max) {
 261                                                 _terraform_err_tile = t; // highlight the tile under the bridge
 262                                                 return_cmd_error(STR_ERROR_MUST_DEMOLISH_BRIDGE_FIRST);
 263                                         }
 264
 265                                         /* Is the bridge above not too high afterwards? */
 266                                         if (direction == -1 && bridge_height > (z_min + _settings_game.construction.max_bridge_height)) {
 267                                                 _terraform_err_tile = t;
 268                                                 return_cmd_error(STR_ERROR_BRIDGE_TOO_HIGH_AFTER_LOWER_LAND);
 269                                         }
 270                                 }
 271                                 /* Check if tunnel would take damage */
 272                                 if (direction == -1 && IsTunnelInWay(t, z_min)) {
 273                                         _terraform_err_tile = t; // highlight the tile above the tunnel
 274                                         return_cmd_error(STR_ERROR_EXCAVATION_WOULD_DAMAGE);
 275                                 }
 276                         }
 277
 278                         /* Is the tile already cleared? */
 279                         const ClearedObjectArea *coa = FindClearedObject(t);
 280                         bool indirectly_cleared = coa != nullptr && coa->first_tile != t;
 281
 282                         /* Check tiletype-specific things, and add extra-cost */
 283                         Backup<bool> old_generating_world(_generating_world, FILE_LINE);
 284                         if (_game_mode == GM_EDITOR) old_generating_world.Change(true); // used to create green terraformed land
 285                         DoCommandFlag tile_flags = flags | DC_AUTO | DC_FORCE_CLEAR_TILE;
 286                         if (pass == 0) {
 287                                 tile_flags &= ~DC_EXEC;
 288                                 tile_flags |= DC_NO_MODIFY_TOWN_RATING;
 289                         }
 290                         CommandCost cost;
 291                         if (indirectly_cleared) {
 292                                 cost = DoCommand(t, 0, 0, tile_flags, CMD_LANDSCAPE_CLEAR);
 293                         } else {
 294                                 cost = _tile_type_procs[GetTileType(t)]->terraform_tile_proc(t, tile_flags, z_min, tileh);
 295                         }
 296                         old_generating_world.Restore();
 297                         if (cost.Failed()) {
 298                                 _terraform_err_tile = t;
 299                                 return cost;
 300                         }
 301                         if (pass == 1) total_cost.AddCost(cost);
 302                 }
 303         }
 304
 305         Company *c = Company::GetIfValid(_current_company);
 306         if (c != nullptr && GB(c->terraform_limit, 16, 16) < ts.tile_to_new_height.size()) {
 307                 return_cmd_error(STR_ERROR_TERRAFORM_LIMIT_REACHED);
 308         }
 309
 310         if (flags & DC_EXEC) {
 311                 /* Mark affected areas dirty. */
 312                 for (TileIndexSet::const_iterator it = ts.dirty_tiles.begin(); it != ts.dirty_tiles.end(); it++) {
 313                         MarkTileDirtyByTile(*it);
 314                         TileIndexToHeightMap::const_iterator new_height = ts.tile_to_new_height.find(*it);
 315                         if (new_height == ts.tile_to_new_height.end()) continue;
 316                         MarkTileDirtyByTile(*it, 0, new_height->second);
 317                 }
 318
 319                 /* change the height */
 320                 for (TileIndexToHeightMap::const_iterator it = ts.tile_to_new_height.begin();
 321                                 it != ts.tile_to_new_height.end(); it++) {
 322                         TileIndex t = it->first;
 323                         int height = it->second;
 324
 325                         SetTileHeight(t, (uint)height);
 326                 }
 327
 328                 if (c != nullptr) c->terraform_limit -= (uint32)ts.tile_to_new_height.size() << 16;
 329         }
 330         return total_cost;
 331 }
 332
 333
 334 /**
 335  * Levels a selected (rectangle) area of land
 336  * @param tile end tile of area-drag
 337  * @param flags for this command type
 338  * @param p1 start tile of area drag
 339  * @param p2 various bitstuffed data.
 340  *  bit      0: Whether to use the Orthogonal (0) or Diagonal (1) iterator.
 341  *  bits 1 - 2: Mode of leveling \c LevelMode.
 342  * @param text unused
 343  * @return the cost of this operation or an error
 344  */
 345 CommandCost CmdLevelLand(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const std::string &text)
 346 {
 347         if (p1 >= MapSize()) return CMD_ERROR;
 348
 349         _terraform_err_tile = INVALID_TILE;
 350
 351         /* remember level height */
 352         uint oldh = TileHeight(p1);
 353
 354         /* compute new height */
 355         uint h = oldh;
 356         LevelMode lm = (LevelMode)GB(p2, 1, 2);
 357         switch (lm) {
 358                 case LM_LEVEL: break;
 359                 case LM_RAISE: h++; break;
 360                 case LM_LOWER: h--; break;
 361                 default: return CMD_ERROR;
 362         }
 363
 364         /* Check range of destination height */
 365         if (h > _settings_game.construction.map_height_limit) return_cmd_error((oldh == 0) ? STR_ERROR_ALREADY_AT_SEA_LEVEL : STR_ERROR_TOO_HIGH);
 366
 367         Money money = GetAvailableMoneyForCommand();
 368         CommandCost cost(EXPENSES_CONSTRUCTION);
 369         CommandCost last_error(lm == LM_LEVEL ? STR_ERROR_ALREADY_LEVELLED : INVALID_STRING_ID);
 370         bool had_success = false;
 371
 372         const Company *c = Company::GetIfValid(_current_company);
 373         int limit = (c == nullptr ? INT32_MAX : GB(c->terraform_limit, 16, 16));
 374         if (limit == 0) return_cmd_error(STR_ERROR_TERRAFORM_LIMIT_REACHED);
 375
 376         TileIterator *iter = HasBit(p2, 0) ? (TileIterator *)new DiagonalTileIterator(tile, p1) : new OrthogonalTileIterator(tile, p1);
 377         for (; *iter != INVALID_TILE; ++(*iter)) {
 378                 TileIndex t = *iter;
 379                 uint curh = TileHeight(t);
 380                 while (curh != h) {
 381                         CommandCost ret = DoCommand(t, SLOPE_N, (curh > h) ? 0 : 1, flags & ~DC_EXEC, CMD_TERRAFORM_LAND);
 382                         if (ret.Failed()) {
 383                                 last_error = ret;
 384
 385                                 /* Did we reach the limit? */
 386                                 if (ret.GetErrorMessage() == STR_ERROR_TERRAFORM_LIMIT_REACHED) limit = 0;
 387                                 break;
 388                         }
 389
 390                         if (flags & DC_EXEC) {
 391                                 money -= ret.GetCost();
 392                                 if (money < 0) {
 393                                         _additional_cash_required = ret.GetCost();
 394                                         delete iter;
 395                                         return cost;
 396                                 }
 397                                 DoCommand(t, SLOPE_N, (curh > h) ? 0 : 1, flags, CMD_TERRAFORM_LAND);
 398                         } else {
 399                                 /* When we're at the terraform limit we better bail (unneeded) testing as well.
 400                                  * This will probably cause the terraforming cost to be underestimated, but only
 401                                  * when it's near the terraforming limit. Even then, the estimation is
 402                                  * completely off due to it basically counting terraforming double, so it being
 403                                  * cut off earlier might even give a better estimate in some cases. */
 404                                 if (--limit <= 0) {
 405                                         had_success = true;
 406                                         break;
 407                                 }
 408                         }
 409
 410                         cost.AddCost(ret);
 411                         curh += (curh > h) ? -1 : 1;
 412                         had_success = true;
 413                 }
 414
 415                 if (limit <= 0) break;
 416         }
 417
 418         delete iter;
 419         return had_success ? cost : last_error;
 420 }