OpenTTD-patches/src/map_func.h
Peter Nelson ab535c0a86
Codechange: Add base() method to StrongType to allow access to the base type without casting. (#11445)
This removes the ability to explicitly cast to the base type, but the requirement
to use .base() means the conversion is still explicit.
2023-11-06 20:29:35 +00:00

662 lines
18 KiB
C++

/*
* This file is part of OpenTTD.
* 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.
* 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.
* 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/>.
*/
/** @file map_func.h Functions related to maps. */
#ifndef MAP_FUNC_H
#define MAP_FUNC_H
#include "core/math_func.hpp"
#include "tile_type.h"
#include "map_type.h"
#include "direction_func.h"
/**
* Wrapper class to abstract away the way the tiles are stored. It is
* intended to be used to access the "map" data of a single tile.
*
* The wrapper is expected to be fully optimized away by the compiler, even
* with low optimization levels except when completely disabling it.
*/
class Tile {
private:
friend struct Map;
/**
* Data that is stored per tile. Also used TileExtended for this.
* Look at docs/landscape.html for the exact meaning of the members.
*/
struct TileBase {
byte type; ///< The type (bits 4..7), bridges (2..3), rainforest/desert (0..1)
byte height; ///< The height of the northern corner.
uint16_t m2; ///< Primarily used for indices to towns, industries and stations
byte m1; ///< Primarily used for ownership information
byte m3; ///< General purpose
byte m4; ///< General purpose
byte m5; ///< General purpose
};
static_assert(sizeof(TileBase) == 8);
/**
* Data that is stored per tile. Also used TileBase for this.
* Look at docs/landscape.html for the exact meaning of the members.
*/
struct TileExtended {
byte m6; ///< General purpose
byte m7; ///< Primarily used for newgrf support
uint16_t m8; ///< General purpose
};
static TileBase *base_tiles; ///< Pointer to the tile-array.
static TileExtended *extended_tiles; ///< Pointer to the extended tile-array.
TileIndex tile; ///< The tile to access the map data for.
public:
/**
* Create the tile wrapper for the given tile.
* @param tile The tile to access the map for.
*/
debug_inline Tile(TileIndex tile) : tile(tile) {}
/**
* Create the tile wrapper for the given tile.
* @param tile The tile to access the map for.
*/
Tile(uint tile) : tile(tile) {}
/**
* Implicit conversion to the TileIndex.
*/
debug_inline constexpr operator TileIndex() const { return tile; }
/**
* Implicit conversion to the uint for bounds checking.
*/
debug_inline constexpr operator uint() const { return tile.base(); }
/**
* The type (bits 4..7), bridges (2..3), rainforest/desert (0..1)
*
* Look at docs/landscape.html for the exact meaning of the data.
* @param tile The tile to get the data for.
* @return reference to the byte holding the data.
*/
debug_inline byte &type()
{
return base_tiles[tile.base()].type;
}
/**
* The height of the northern corner
*
* Look at docs/landscape.html for the exact meaning of the data.
* @param tile The tile to get the height for.
* @return reference to the byte holding the height.
*/
debug_inline byte &height()
{
return base_tiles[tile.base()].height;
}
/**
* Primarily used for ownership information
*
* Look at docs/landscape.html for the exact meaning of the data.
* @param tile The tile to get the data for.
* @return reference to the byte holding the data.
*/
debug_inline byte &m1()
{
return base_tiles[tile.base()].m1;
}
/**
* Primarily used for indices to towns, industries and stations
*
* Look at docs/landscape.html for the exact meaning of the data.
* @param tile The tile to get the data for.
* @return reference to the uint16_t holding the data.
*/
debug_inline uint16_t &m2()
{
return base_tiles[tile.base()].m2;
}
/**
* General purpose
*
* Look at docs/landscape.html for the exact meaning of the data.
* @param tile The tile to get the data for.
* @return reference to the byte holding the data.
*/
debug_inline byte &m3()
{
return base_tiles[tile.base()].m3;
}
/**
* General purpose
*
* Look at docs/landscape.html for the exact meaning of the data.
* @param tile The tile to get the data for.
* @return reference to the byte holding the data.
*/
debug_inline byte &m4()
{
return base_tiles[tile.base()].m4;
}
/**
* General purpose
*
* Look at docs/landscape.html for the exact meaning of the data.
* @param tile The tile to get the data for.
* @return reference to the byte holding the data.
*/
debug_inline byte &m5()
{
return base_tiles[tile.base()].m5;
}
/**
* General purpose
*
* Look at docs/landscape.html for the exact meaning of the data.
* @param tile The tile to get the data for.
* @return reference to the byte holding the data.
*/
debug_inline byte &m6()
{
return extended_tiles[tile.base()].m6;
}
/**
* Primarily used for newgrf support
*
* Look at docs/landscape.html for the exact meaning of the data.
* @param tile The tile to get the data for.
* @return reference to the byte holding the data.
*/
debug_inline byte &m7()
{
return extended_tiles[tile.base()].m7;
}
/**
* General purpose
*
* Look at docs/landscape.html for the exact meaning of the data.
* @param tile The tile to get the data for.
* @return reference to the uint16_t holding the data.
*/
debug_inline uint16_t &m8()
{
return extended_tiles[tile.base()].m8;
}
};
/**
* Size related data of the map.
*/
struct Map {
private:
/**
* Iterator to iterate all Tiles
*/
struct Iterator {
typedef Tile value_type;
typedef Tile *pointer;
typedef Tile &reference;
typedef size_t difference_type;
typedef std::forward_iterator_tag iterator_category;
explicit Iterator(TileIndex index) : index(index) {}
bool operator==(const Iterator &other) const { return this->index == other.index; }
bool operator!=(const Iterator &other) const { return !(*this == other); }
Tile operator*() const { return this->index; }
Iterator & operator++() { this->index++; return *this; }
private:
TileIndex index;
};
/*
* Iterable ensemble of all Tiles
*/
struct IterateWrapper {
Iterator begin() { return Iterator(0); }
Iterator end() { return Iterator(Map::Size()); }
bool empty() { return false; }
};
static uint log_x; ///< 2^_map_log_x == _map_size_x
static uint log_y; ///< 2^_map_log_y == _map_size_y
static uint size_x; ///< Size of the map along the X
static uint size_y; ///< Size of the map along the Y
static uint size; ///< The number of tiles on the map
static uint tile_mask; ///< _map_size - 1 (to mask the mapsize)
public:
static void Allocate(uint size_x, uint size_y);
/**
* Logarithm of the map size along the X side.
* @note try to avoid using this one
* @return 2^"return value" == Map::SizeX()
*/
debug_inline static uint LogX()
{
return Map::log_x;
}
/**
* Logarithm of the map size along the y side.
* @note try to avoid using this one
* @return 2^"return value" == Map::SizeY()
*/
static inline uint LogY()
{
return Map::log_y;
}
/**
* Get the size of the map along the X
* @return the number of tiles along the X of the map
*/
debug_inline static uint SizeX()
{
return Map::size_x;
}
/**
* Get the size of the map along the Y
* @return the number of tiles along the Y of the map
*/
static inline uint SizeY()
{
return Map::size_y;
}
/**
* Get the size of the map
* @return the number of tiles of the map
*/
debug_inline static uint Size()
{
return Map::size;
}
/**
* Gets the maximum X coordinate within the map, including MP_VOID
* @return the maximum X coordinate
*/
debug_inline static uint MaxX()
{
return Map::SizeX() - 1;
}
/**
* Gets the maximum Y coordinate within the map, including MP_VOID
* @return the maximum Y coordinate
*/
static inline uint MaxY()
{
return Map::SizeY() - 1;
}
/**
* 'Wraps' the given "tile" so it is within the map.
* It does this by masking the 'high' bits of.
* @param tile the tile to 'wrap'
*/
static inline TileIndex WrapToMap(TileIndex tile)
{
return tile.base() & Map::tile_mask;
}
/**
* 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
*/
static inline uint ScaleBySize(uint n)
{
/* Subtract 12 from shift in order to prevent integer overflow
* for large values of n. It's safe since the min mapsize is 64x64. */
return CeilDiv(n << (Map::LogX() + Map::LogY() - 12), 1 << 4);
}
/**
* 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
*/
static inline uint ScaleBySize1D(uint n)
{
/* Normal circumference for the X+Y is 256+256 = 1<<9
* Note, not actually taking the full circumference into account,
* just half of it. */
return CeilDiv((n << Map::LogX()) + (n << Map::LogY()), 1 << 9);
}
/**
* Check whether the map has been initialized, as to not try to save the map
* during crashlog when the map is not there yet.
* @return true when the map has been allocated/initialized.
*/
static bool IsInitialized()
{
return Tile::base_tiles != nullptr;
}
/**
* Returns an iterable ensemble of all Tiles
* @return an iterable ensemble of all Tiles
*/
static IterateWrapper Iterate() { return IterateWrapper(); }
};
/**
* An offset value between two tiles.
*
* This value is used for the difference between
* two tiles. It can be added to a TileIndex to get
* the resulting TileIndex of the start tile applied
* with this saved difference.
*
* @see TileDiffXY(int, int)
*/
typedef int32_t TileIndexDiff;
/**
* Returns the TileIndex of a coordinate.
*
* @param x The x coordinate of the tile
* @param y The y coordinate of the tile
* @return The TileIndex calculated by the coordinate
*/
debug_inline static TileIndex TileXY(uint x, uint y)
{
return (y << Map::LogX()) + x;
}
/**
* Calculates an offset for the given coordinate(-offset).
*
* This function calculate an offset value which can be added to a
* #TileIndex. The coordinates can be negative.
*
* @param x The offset in x direction
* @param y The offset in y direction
* @return The resulting offset value of the given coordinate
* @see ToTileIndexDiff(TileIndexDiffC)
*/
static inline TileIndexDiff TileDiffXY(int x, int y)
{
/* Multiplication gives much better optimization on MSVC than shifting.
* 0 << shift isn't optimized to 0 properly.
* Typically x and y are constants, and then this doesn't result
* in any actual multiplication in the assembly code.. */
return (y * Map::SizeX()) + x;
}
/**
* Get a tile from the virtual XY-coordinate.
* @param x The virtual x coordinate of the tile.
* @param y The virtual y coordinate of the tile.
* @return The TileIndex calculated by the coordinate.
*/
debug_inline static TileIndex TileVirtXY(uint x, uint y)
{
return (y >> 4 << Map::LogX()) + (x >> 4);
}
/**
* Get the X component of a tile
* @param tile the tile to get the X component of
* @return the X component
*/
debug_inline static uint TileX(TileIndex tile)
{
return tile.base() & Map::MaxX();
}
/**
* Get the Y component of a tile
* @param tile the tile to get the Y component of
* @return the Y component
*/
debug_inline static uint TileY(TileIndex tile)
{
return tile.base() >> Map::LogX();
}
/**
* Return the offset between two tiles from a TileIndexDiffC struct.
*
* This function works like #TileDiffXY(int, int) and returns the
* difference between two tiles.
*
* @param tidc The coordinate of the offset as TileIndexDiffC
* @return The difference between two tiles.
* @see TileDiffXY(int, int)
*/
static inline TileIndexDiff ToTileIndexDiff(TileIndexDiffC tidc)
{
return (tidc.y << Map::LogX()) + tidc.x;
}
#ifndef _DEBUG
/**
* Adds two tiles together.
*
* @param x One tile
* @param y Another tile to add
* @return The resulting tile(index)
*/
# define TILE_ADD(x, y) ((x) + (y))
#else
extern TileIndex TileAdd(TileIndex tile, TileIndexDiff add,
const char *exp, const char *file, int line);
# define TILE_ADD(x, y) (TileAdd((x), (y), #x " + " #y, __FILE__, __LINE__))
#endif
/**
* Adds a given offset to a tile.
*
* @param tile The tile to add an offset on it
* @param x The x offset to add to the tile
* @param y The y offset to add to the tile
*/
#define TILE_ADDXY(tile, x, y) TILE_ADD(tile, TileDiffXY(x, y))
TileIndex TileAddWrap(TileIndex tile, int addx, int addy);
/**
* Returns the TileIndexDiffC offset from a DiagDirection.
*
* @param dir The given direction
* @return The offset as TileIndexDiffC value
*/
static inline TileIndexDiffC TileIndexDiffCByDiagDir(DiagDirection dir)
{
extern const TileIndexDiffC _tileoffs_by_diagdir[DIAGDIR_END];
assert(IsValidDiagDirection(dir));
return _tileoffs_by_diagdir[dir];
}
/**
* Returns the TileIndexDiffC offset from a Direction.
*
* @param dir The given direction
* @return The offset as TileIndexDiffC value
*/
static inline TileIndexDiffC TileIndexDiffCByDir(Direction dir)
{
extern const TileIndexDiffC _tileoffs_by_dir[DIR_END];
assert(IsValidDirection(dir));
return _tileoffs_by_dir[dir];
}
/**
* Add a TileIndexDiffC to a TileIndex and returns the new one.
*
* Returns tile + the diff given in diff. If the result tile would end up
* outside of the map, INVALID_TILE is returned instead.
*
* @param tile The base tile to add the offset on
* @param diff The offset to add on the tile
* @return The resulting TileIndex
*/
static inline TileIndex AddTileIndexDiffCWrap(TileIndex tile, TileIndexDiffC diff)
{
int x = TileX(tile) + diff.x;
int y = TileY(tile) + diff.y;
/* Negative value will become big positive value after cast */
if ((uint)x >= Map::SizeX() || (uint)y >= Map::SizeY()) return INVALID_TILE;
return TileXY(x, y);
}
/**
* Returns the diff between two tiles
*
* @param tile_a from tile
* @param tile_b to tile
* @return the difference between tila_a and tile_b
*/
static inline TileIndexDiffC TileIndexToTileIndexDiffC(TileIndex tile_a, TileIndex tile_b)
{
TileIndexDiffC difference;
difference.x = TileX(tile_a) - TileX(tile_b);
difference.y = TileY(tile_a) - TileY(tile_b);
return difference;
}
/* Functions to calculate distances */
uint DistanceManhattan(TileIndex, TileIndex); ///< also known as L1-Norm. Is the shortest distance one could go over diagonal tracks (or roads)
uint DistanceSquare(TileIndex, TileIndex); ///< euclidian- or L2-Norm squared
uint DistanceMax(TileIndex, TileIndex); ///< also known as L-Infinity-Norm
uint DistanceMaxPlusManhattan(TileIndex, TileIndex); ///< Max + Manhattan
uint DistanceFromEdge(TileIndex); ///< shortest distance from any edge of the map
uint DistanceFromEdgeDir(TileIndex, DiagDirection); ///< distance from the map edge in given direction
/**
* Convert a DiagDirection to a TileIndexDiff
*
* @param dir The DiagDirection
* @return The resulting TileIndexDiff
* @see TileIndexDiffCByDiagDir
*/
static inline TileIndexDiff TileOffsByDiagDir(DiagDirection dir)
{
extern const TileIndexDiffC _tileoffs_by_diagdir[DIAGDIR_END];
assert(IsValidDiagDirection(dir));
return ToTileIndexDiff(_tileoffs_by_diagdir[dir]);
}
/**
* Convert a Direction to a TileIndexDiff.
*
* @param dir The direction to convert from
* @return The resulting TileIndexDiff
*/
static inline TileIndexDiff TileOffsByDir(Direction dir)
{
extern const TileIndexDiffC _tileoffs_by_dir[DIR_END];
assert(IsValidDirection(dir));
return ToTileIndexDiff(_tileoffs_by_dir[dir]);
}
/**
* Adds a Direction to a tile.
*
* @param tile The current tile
* @param dir The direction in which we want to step
* @return the moved tile
*/
static inline TileIndex TileAddByDir(TileIndex tile, Direction dir)
{
return TILE_ADD(tile, TileOffsByDir(dir));
}
/**
* Adds a DiagDir to a tile.
*
* @param tile The current tile
* @param dir The direction in which we want to step
* @return the moved tile
*/
static inline TileIndex TileAddByDiagDir(TileIndex tile, DiagDirection dir)
{
return TILE_ADD(tile, TileOffsByDiagDir(dir));
}
/**
* Determines the DiagDirection to get from one tile to another.
* The tiles do not necessarily have to be adjacent.
* @param tile_from Origin tile
* @param tile_to Destination tile
* @return DiagDirection from tile_from towards tile_to, or INVALID_DIAGDIR if the tiles are not on an axis
*/
static inline DiagDirection DiagdirBetweenTiles(TileIndex tile_from, TileIndex tile_to)
{
int dx = (int)TileX(tile_to) - (int)TileX(tile_from);
int dy = (int)TileY(tile_to) - (int)TileY(tile_from);
if (dx == 0) {
if (dy == 0) return INVALID_DIAGDIR;
return (dy < 0 ? DIAGDIR_NW : DIAGDIR_SE);
} else {
if (dy != 0) return INVALID_DIAGDIR;
return (dx < 0 ? DIAGDIR_NE : DIAGDIR_SW);
}
}
/**
* A callback function type for searching tiles.
*
* @param tile The tile to test
* @param user_data additional data for the callback function to use
* @return A boolean value, depend on the definition of the function.
*/
typedef bool TestTileOnSearchProc(TileIndex tile, void *user_data);
bool CircularTileSearch(TileIndex *tile, uint size, TestTileOnSearchProc proc, void *user_data);
bool CircularTileSearch(TileIndex *tile, uint radius, uint w, uint h, TestTileOnSearchProc proc, void *user_data);
/**
* Get a random tile out of a given seed.
* @param r the random 'seed'
* @return a valid tile
*/
static inline TileIndex RandomTileSeed(uint32_t r)
{
return Map::WrapToMap(r);
}
/**
* Get a valid random tile.
* @note a define so 'random' gets inserted in the place where it is actually
* called, thus making the random traces more explicit.
* @return a valid tile
*/
#define RandomTile() RandomTileSeed(Random())
uint GetClosestWaterDistance(TileIndex tile, bool water);
#endif /* MAP_FUNC_H */