# map.cpp

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    00001 /* $Id$ */
    00002
    00003 /*
    00004  * This file is part of OpenTTD.
    00005  * 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.
    00006  * 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.
    00007  * 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/>.
    00008  */
    00009
    00012 #include "stdafx.h"
    00013 #include "debug.h"
    00014 #include "core/alloc_func.hpp"
    00015 #include "tile_map.h"
    00016 #include "water_map.h"
    00017
    00018 #if defined(_MSC_VER)
    00019 /* Why the hell is that not in all MSVC headers?? */
    00020 extern "C" _CRTIMP void __cdecl _assert(void *, void *, unsigned);
    00021 #endif
    00022
    00023 uint _map_log_x;
    00024 uint _map_log_y;
    00025 uint _map_size_x;
    00026 uint _map_size_y;
    00027 uint _map_size;
    00028 uint _map_tile_mask;
    00029
    00030 Tile *_m = NULL;
    00031 TileExtended *_me = NULL;
    00032
    00033
    00039 void AllocateMap(uint size_x, uint size_y)
    00040 {
    00041   /* Make sure that the map size is within the limits and that
    00042    * size of both axes is a power of 2. */
    00043   if (!IsInsideMM(size_x, MIN_MAP_SIZE, MAX_MAP_SIZE + 1) ||
    00044       !IsInsideMM(size_y, MIN_MAP_SIZE, MAX_MAP_SIZE + 1) ||
    00045       (size_x & (size_x - 1)) != 0 ||
    00046       (size_y & (size_y - 1)) != 0) {
    00047     error("Invalid map size");
    00048   }
    00049
    00050   DEBUG(map, 1, "Allocating map of size %dx%d", size_x, size_y);
    00051
    00052   _map_log_x = FindFirstBit(size_x);
    00053   _map_log_y = FindFirstBit(size_y);
    00054   _map_size_x = size_x;
    00055   _map_size_y = size_y;
    00056   _map_size = size_x * size_y;
    00057   _map_tile_mask = _map_size - 1;
    00058
    00059   free(_m);
    00060   free(_me);
    00061
    00062   _m = CallocT<Tile>(_map_size);
    00063   _me = CallocT<TileExtended>(_map_size);
    00064 }
    00065
    00066
    00067 #ifdef _DEBUG
    00068 TileIndex TileAdd(TileIndex tile, TileIndexDiff add,
    00069   const char *exp, const char *file, int line)
    00070 {
    00071   int dx;
    00072   int dy;
    00073   uint x;
    00074   uint y;
    00075
    00076   dx = add & MapMaxX();
    00077   if (dx >= (int)MapSizeX() / 2) dx -= MapSizeX();
    00078   dy = (add - dx) / (int)MapSizeX();
    00079
    00080   x = TileX(tile) + dx;
    00081   y = TileY(tile) + dy;
    00082
    00083   if (x >= MapSizeX() || y >= MapSizeY()) {
    00084     char buf[512];
    00085
    00086     snprintf(buf, lengthof(buf), "TILE_ADD(%s) when adding 0x%.4X and 0x%.4X failed",
    00087       exp, tile, add);
    00088 #if !defined(_MSC_VER) || defined(WINCE)
    00089     fprintf(stderr, "%s:%d %s\n", file, line, buf);
    00090 #else
    00091     _assert(buf, (char*)file, line);
    00092 #endif
    00093   }
    00094
    00095   assert(TileXY(x, y) == TILE_MASK(tile + add));
    00096
    00097   return TileXY(x, y);
    00098 }
    00099 #endif
    00100
    00114 TileIndex TileAddWrap(TileIndex tile, int addx, int addy)
    00115 {
    00116   uint x = TileX(tile) + addx;
    00117   uint y = TileY(tile) + addy;
    00118
    00119   /* Disallow void tiles at the north border. */
    00120   if (_settings_game.construction.freeform_edges && (x == 0 || y == 0)) return INVALID_TILE;
    00121
    00122   /* Are we about to wrap? */
    00123   if (x < MapMaxX() && y < MapMaxY()) return tile + TileDiffXY(addx, addy);
    00124
    00125   return INVALID_TILE;
    00126 }
    00127
    00129 extern const TileIndexDiffC _tileoffs_by_diagdir[] = {
    00130   {-1,  0},
    00131   { 0,  1},
    00132   { 1,  0},
    00133   { 0, -1}
    00134 };
    00135
    00137 extern const TileIndexDiffC _tileoffs_by_dir[] = {
    00138   {-1, -1},
    00139   {-1,  0},
    00140   {-1,  1},
    00141   { 0,  1},
    00142   { 1,  1},
    00143   { 1,  0},
    00144   { 1, -1},
    00145   { 0, -1}
    00146 };
    00147
    00157 uint DistanceManhattan(TileIndex t0, TileIndex t1)
    00158 {
    00159   const uint dx = Delta(TileX(t0), TileX(t1));
    00160   const uint dy = Delta(TileY(t0), TileY(t1));
    00161   return dx + dy;
    00162 }
    00163
    00164
    00174 uint DistanceSquare(TileIndex t0, TileIndex t1)
    00175 {
    00176   const int dx = TileX(t0) - TileX(t1);
    00177   const int dy = TileY(t0) - TileY(t1);
    00178   return dx * dx + dy * dy;
    00179 }
    00180
    00181
    00189 uint DistanceMax(TileIndex t0, TileIndex t1)
    00190 {
    00191   const uint dx = Delta(TileX(t0), TileX(t1));
    00192   const uint dy = Delta(TileY(t0), TileY(t1));
    00193   return max(dx, dy);
    00194 }
    00195
    00196
    00205 uint DistanceMaxPlusManhattan(TileIndex t0, TileIndex t1)
    00206 {
    00207   const uint dx = Delta(TileX(t0), TileX(t1));
    00208   const uint dy = Delta(TileY(t0), TileY(t1));
    00209   return dx > dy ? 2 * dx + dy : 2 * dy + dx;
    00210 }
    00211
    00217 uint DistanceFromEdge(TileIndex tile)
    00218 {
    00219   const uint xl = TileX(tile);
    00220   const uint yl = TileY(tile);
    00221   const uint xh = MapSizeX() - 1 - xl;
    00222   const uint yh = MapSizeY() - 1 - yl;
    00223   const uint minl = min(xl, yl);
    00224   const uint minh = min(xh, yh);
    00225   return min(minl, minh);
    00226 }
    00227
    00234 uint DistanceFromEdgeDir(TileIndex tile, DiagDirection dir)
    00235 {
    00236   switch (dir) {
    00237     case DIAGDIR_NE: return             TileX(tile) - (_settings_game.construction.freeform_edges ? 1 : 0);
    00238     case DIAGDIR_NW: return             TileY(tile) - (_settings_game.construction.freeform_edges ? 1 : 0);
    00239     case DIAGDIR_SW: return MapMaxX() - TileX(tile) - 1;
    00240     case DIAGDIR_SE: return MapMaxY() - TileY(tile) - 1;
    00241     default: NOT_REACHED();
    00242   }
    00243 }
    00244
    00258 bool CircularTileSearch(TileIndex *tile, uint size, TestTileOnSearchProc proc, void *user_data)
    00259 {
    00260   assert(proc != NULL);
    00261   assert(size > 0);
    00262
    00263   if (size % 2 == 1) {
    00264     /* If the length of the side is uneven, the center has to be checked
    00265      * separately, as the pattern of uneven sides requires to go around the center */
    00266     if (proc(*tile, user_data)) return true;
    00267
    00268     /* If tile test is not successful, get one tile up,
    00269      * ready for a test in first circle around center tile */
    00270     *tile = TILE_ADD(*tile, TileOffsByDir(DIR_N));
    00271     return CircularTileSearch(tile, size / 2, 1, 1, proc, user_data);
    00272   } else {
    00273     return CircularTileSearch(tile, size / 2, 0, 0, proc, user_data);
    00274   }
    00275 }
    00276
    00296 bool CircularTileSearch(TileIndex *tile, uint radius, uint w, uint h, TestTileOnSearchProc proc, void *user_data)
    00297 {
    00298   assert(proc != NULL);
    00299   assert(radius > 0);
    00300
    00301   uint x = TileX(*tile) + w + 1;
    00302   uint y = TileY(*tile);
    00303
    00304   const uint extent[DIAGDIR_END] = { w, h, w, h };
    00305
    00306   for (uint n = 0; n < radius; n++) {
    00307     for (DiagDirection dir = DIAGDIR_BEGIN; dir < DIAGDIR_END; dir++) {
    00308       /* Is the tile within the map? */
    00309       for (uint j = extent[dir] + n * 2 + 1; j != 0; j--) {
    00310         if (x < MapSizeX() && y < MapSizeY()) {
    00311           TileIndex t = TileXY(x, y);
    00312           /* Is the callback successful? */
    00313           if (proc(t, user_data)) {
    00314             /* Stop the search */
    00315             *tile = t;
    00316             return true;
    00317           }
    00318         }
    00319
    00320         /* Step to the next 'neighbour' in the circular line */
    00321         x += _tileoffs_by_diagdir[dir].x;
    00322         y += _tileoffs_by_diagdir[dir].y;
    00323       }
    00324     }
    00325     /* Jump to next circle to test */
    00326     x += _tileoffs_by_dir[DIR_W].x;
    00327     y += _tileoffs_by_dir[DIR_W].y;
    00328   }
    00329
    00330   *tile = INVALID_TILE;
    00331   return false;
    00332 }
    00333
    00340 uint GetClosestWaterDistance(TileIndex tile, bool water)
    00341 {
    00342   if (HasTileWaterGround(tile) == water) return 0;
    00343
    00344   uint max_dist = water ? 0x7F : 0x200;
    00345
    00346   int x = TileX(tile);
    00347   int y = TileY(tile);
    00348
    00349   uint max_x = MapMaxX();
    00350   uint max_y = MapMaxY();
    00351   uint min_xy = _settings_game.construction.freeform_edges ? 1 : 0;
    00352
    00353   /* go in a 'spiral' with increasing manhattan distance in each iteration */
    00354   for (uint dist = 1; dist < max_dist; dist++) {
    00355     /* next 'diameter' */
    00356     y--;
    00357
    00358     /* going counter-clockwise around this square */
    00359     for (DiagDirection dir = DIAGDIR_BEGIN; dir < DIAGDIR_END; dir++) {
    00360       static const int8 ddx[DIAGDIR_END] = { -1,  1,  1, -1};
    00361       static const int8 ddy[DIAGDIR_END] = {  1,  1, -1, -1};
    00362
    00363       int dx = ddx[dir];
    00364       int dy = ddy[dir];
    00365
    00366       /* each side of this square has length 'dist' */
    00367       for (uint a = 0; a < dist; a++) {
    00368         /* MP_VOID tiles are not checked (interval is [min; max) for IsInsideMM())*/
    00369         if (IsInsideMM(x, min_xy, max_x) && IsInsideMM(y, min_xy, max_y)) {
    00370           TileIndex t = TileXY(x, y);
    00371           if (HasTileWaterGround(t) == water) return dist;
    00372         }
    00373         x += dx;
    00374         y += dy;
    00375       }
    00376     }
    00377   }
    00378
    00379   if (!water) {
    00380     /* no land found - is this a water-only map? */
    00381     for (TileIndex t = 0; t < MapSize(); t++) {
    00382       if (!IsTileType(t, MP_VOID) && !IsTileType(t, MP_WATER)) return 0x1FF;
    00383     }
    00384   }
    00385
    00386   return max_dist;
    00387 }