diff options
Diffstat (limited to 'src/map.cpp')
| -rw-r--r-- | src/map.cpp | 87 |
1 files changed, 74 insertions, 13 deletions
diff --git a/src/map.cpp b/src/map.cpp index 092603b4d..5e511772f 100644 --- a/src/map.cpp +++ b/src/map.cpp @@ -16,24 +16,29 @@ extern "C" _CRTIMP void __cdecl _assert(void *, void *, unsigned); #endif -uint _map_log_x; -uint _map_size_x; -uint _map_size_y; -uint _map_tile_mask; -uint _map_size; +uint _map_log_x; ///< 2^_map_log_x == _map_size_x +uint _map_size_x; ///< Size of the map along the X +uint _map_size_y; ///< Size of the map along the Y +uint _map_size; ///< The number of tiles on the map +uint _map_tile_mask; ///< _map_size - 1 (to mask the mapsize) -Tile *_m = NULL; -TileExtended *_me = NULL; +Tile *_m = NULL; ///< Tiles of the map +TileExtended *_me = NULL; ///< Extended Tiles of the map +/** + * (Re)allocates a map with the given dimension + * @param size_x the width of the map along the NE/SW edge + * @param size_y the 'height' of the map along the SE/NW edge + */ void AllocateMap(uint size_x, uint size_y) { /* Make sure that the map size is within the limits and that * the x axis size is a power of 2. */ if (size_x < 64 || size_x > 2048 || size_y < 64 || size_y > 2048 || - (size_x&(size_x-1)) != 0 || - (size_y&(size_y-1)) != 0) + (size_x & (size_x - 1)) != 0 || + (size_y & (size_y - 1)) != 0) error("Invalid map size"); DEBUG(map, 1, "Allocating map of size %dx%d", size_x, size_y); @@ -92,7 +97,12 @@ TileIndex TileAdd(TileIndex tile, TileIndexDiff add, } #endif - +/** + * Scales the given value by the map size, where the given value is + * for a 256 by 256 map + * @param n the value to scale + * @return the scaled size + */ uint ScaleByMapSize(uint n) { /* First shift by 12 to prevent integer overflow for large values of n. @@ -102,7 +112,12 @@ uint ScaleByMapSize(uint n) } -/* Scale relative to the circumference of the map */ +/** + * Scales the given value by the maps circumference, where the given + * value is for a 256 by 256 map + * @param n the value to scale + * @return the scaled size + */ uint ScaleByMapSize1D(uint n) { /* Normal circumference for the X+Y is 256+256 = 1<<9 @@ -113,12 +128,18 @@ uint ScaleByMapSize1D(uint n) } -/* This function checks if we add addx/addy to tile, if we +/** + * This function checks if we add addx/addy to tile, if we * do wrap around the edges. For example, tile = (10,2) and * addx = +3 and addy = -4. This function will now return * INVALID_TILE, because the y is wrapped. This is needed in * for example, farmland. When the tile is not wrapped, - * the result will be tile + TileDiffXY(addx, addy) */ + * the result will be tile + TileDiffXY(addx, addy) + * @param tile the 'starting' point of the adding + * @param addx the amount of tiles in the X direction to add + * @param addy the amount of tiles in the Y direction to add + * @return translated tile, or INVALID_TILE when it would've wrapped. + */ uint TileAddWrap(TileIndex tile, int addx, int addy) { uint x = TileX(tile) + addx; @@ -131,6 +152,7 @@ uint TileAddWrap(TileIndex tile, int addx, int addy) return INVALID_TILE; } +/** 'Lookup table' for tile offsets given a DiagDirection */ extern const TileIndexDiffC _tileoffs_by_diagdir[] = { {-1, 0}, ///< DIAGDIR_NE { 0, 1}, ///< DIAGDIR_SE @@ -138,6 +160,7 @@ extern const TileIndexDiffC _tileoffs_by_diagdir[] = { { 0, -1} ///< DIAGDIR_NW }; +/** 'Lookup table' for tile offsets given a Direction */ extern const TileIndexDiffC _tileoffs_by_dir[] = { {-1, -1}, ///< DIR_N {-1, 0}, ///< DIR_NE @@ -149,6 +172,15 @@ extern const TileIndexDiffC _tileoffs_by_dir[] = { { 0, -1} ///< DIR_NW }; +/** + * Gets the Manhattan distance between the two given tiles. + * The Manhattan distance is the sum of the delta of both the + * X and Y component. + * Also known as L1-Norm + * @param t0 the start tile + * @param t1 the end tile + * @return the distance + */ uint DistanceManhattan(TileIndex t0, TileIndex t1) { const uint dx = delta(TileX(t0), TileX(t1)); @@ -157,6 +189,15 @@ uint DistanceManhattan(TileIndex t0, TileIndex t1) } +/** + * Gets the 'Square' distance between the two given tiles. + * The 'Square' distance is the square of the shortest (straight line) + * distance between the two tiles. + * Also known as euclidian- or L2-Norm squared. + * @param t0 the start tile + * @param t1 the end tile + * @return the distance + */ uint DistanceSquare(TileIndex t0, TileIndex t1) { const int dx = TileX(t0) - TileX(t1); @@ -165,6 +206,13 @@ uint DistanceSquare(TileIndex t0, TileIndex t1) } +/** + * Gets the biggest distance component (x or y) between the two given tiles. + * Also known as L-Infinity-Norm. + * @param t0 the start tile + * @param t1 the end tile + * @return the distance + */ uint DistanceMax(TileIndex t0, TileIndex t1) { const uint dx = delta(TileX(t0), TileX(t1)); @@ -173,6 +221,14 @@ uint DistanceMax(TileIndex t0, TileIndex t1) } +/** + * Gets the biggest distance component (x or y) between the two given tiles + * plus the Manhattan distance, i.e. two times the biggest distance component + * and once the smallest component. + * @param t0 the start tile + * @param t1 the end tile + * @return the distance + */ uint DistanceMaxPlusManhattan(TileIndex t0, TileIndex t1) { const uint dx = delta(TileX(t0), TileX(t1)); @@ -180,6 +236,11 @@ uint DistanceMaxPlusManhattan(TileIndex t0, TileIndex t1) return dx > dy ? 2 * dx + dy : 2 * dy + dx; } +/** + * Param the minimum distance to an edge + * @param tile the tile to get the distance from + * @return the distance from the edge in tiles + */ uint DistanceFromEdge(TileIndex tile) { const uint xl = TileX(tile); |