Functions related to maps. More...

#include "core/math_func.hpp"
#include "tile_type.h"
#include "map_type.h"
#include "direction_func.h"

Data Structures
class	Tile
	Wrapper class to abstract away the way the tiles are stored. More...

struct	Tile::TileBase
	Data that is stored per tile. More...

struct	Tile::TileExtended
	Data that is stored per tile. More...

struct	Map
	Size related data of the map. More...

struct	Map::Iterator
	Iterator to iterate all Tiles. More...

struct	Map::IterateWrapper

Macros
#define	RandomTile() RandomTileSeed(Random())
	Get a valid random tile.

Typedefs
typedef bool	TestTileOnSearchProc(TileIndex tile, void *user_data)
	A callback function type for searching tiles.

Functions
static debug_inline TileIndex	TileXY (uint x, uint y)
	Returns the TileIndex of a coordinate.

TileIndexDiff	TileDiffXY (int x, int y)
	Calculates an offset for the given coordinate(-offset).

static debug_inline TileIndex	TileVirtXY (uint x, uint y)
	Get a tile from the virtual XY-coordinate.

static debug_inline uint	TileX (TileIndex tile)
	Get the X component of a tile.

static debug_inline uint	TileY (TileIndex tile)
	Get the Y component of a tile.

TileIndexDiff	ToTileIndexDiff (TileIndexDiffC tidc)
	Return the offset between two tiles from a TileIndexDiffC struct.

constexpr TileIndex	TileAdd (TileIndex tile, TileIndexDiff offset)
	Adds a given offset to a tile.

TileIndex	TileAddXY (TileIndex tile, int x, int y)
	Adds a given offset to a tile.

TileIndex	TileAddWrap (TileIndex tile, int addx, int addy)
	This function checks if we add addx/addy to tile, if we do wrap around the edges.

TileIndexDiffC	TileIndexDiffCByDiagDir (DiagDirection dir)
	Returns the TileIndexDiffC offset from a DiagDirection.

TileIndexDiffC	TileIndexDiffCByDir (Direction dir)
	Returns the TileIndexDiffC offset from a Direction.

TileIndex	AddTileIndexDiffCWrap (TileIndex tile, TileIndexDiffC diff)
	Add a TileIndexDiffC to a TileIndex and returns the new one.

TileIndexDiffC	TileIndexToTileIndexDiffC (TileIndex tile_a, TileIndex tile_b)
	Returns the diff between two tiles.

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

TileIndexDiff	TileOffsByAxis (Axis axis)
	Convert an Axis to a TileIndexDiff.

TileIndexDiff	TileOffsByDiagDir (DiagDirection dir)
	Convert a DiagDirection to a TileIndexDiff.

TileIndexDiff	TileOffsByDir (Direction dir)
	Convert a Direction to a TileIndexDiff.

TileIndex	TileAddByDir (TileIndex tile, Direction dir)
	Adds a Direction to a tile.

TileIndex	TileAddByDiagDir (TileIndex tile, DiagDirection dir)
	Adds a DiagDir to a tile.

DiagDirection	DiagdirBetweenTiles (TileIndex tile_from, TileIndex tile_to)
	Determines the DiagDirection to get from one tile to another.

bool	CircularTileSearch (TileIndex tile, uint size, TestTileOnSearchProc proc, void user_data)
	Function performing a search around a center tile and going outward, thus in circle.

bool	CircularTileSearch (TileIndex tile, uint radius, uint w, uint h, TestTileOnSearchProc proc, void user_data)
	Generalized circular search allowing for rectangles and a hole.

TileIndex	RandomTileSeed (uint32_t r)
	Get a random tile out of a given seed.

uint	GetClosestWaterDistance (TileIndex tile, bool water)
	Finds the distance for the closest tile with water/land given a tile.

Detailed Description

Functions related to maps.

Definition in file map_func.h.

Macro Definition Documentation

◆ RandomTile

#define RandomTile ( ) RandomTileSeed(Random())

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.

Returns: a valid tile

Definition at line 661 of file map_func.h.

Typedef Documentation

◆ TestTileOnSearchProc

typedef bool TestTileOnSearchProc(TileIndex tile, void *user_data)

A callback function type for searching tiles.

Parameters

tile	The tile to test
user_data	additional data for the callback function to use

Returns: A boolean value, depend on the definition of the function.

Definition at line 640 of file map_func.h.

Function Documentation

◆ AddTileIndexDiffCWrap()

TileIndex AddTileIndexDiffCWrap	(	TileIndex	tile,
		TileIndexDiffC	diff
	)

inline

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.

Parameters

tile	The base tile to add the offset on
diff	The offset to add on the tile

Returns: The resulting TileIndex

Definition at line 512 of file map_func.h.

References INVALID_TILE, Map::SizeX(), Map::SizeY(), TileX(), TileXY(), TileY(), TileIndexDiffC::x, and TileIndexDiffC::y.

Referenced by CalculateCoverageLine(), InvalidateWaterRegion(), TerraformTileHeight(), and TileLoop_Water().

◆ CircularTileSearch() [1/2]

bool CircularTileSearch	(	TileIndex *	tile,
		uint	radius,
		uint	w,
		uint	h,
		TestTileOnSearchProc	proc,
		void *	user_data
	)

Generalized circular search allowing for rectangles and a hole.

Function performing a search around a center rectangle and going outward. The center rectangle is left out from the search. To do a rectangular search without a hole, set either h or w to zero. Every tile will be tested by means of the callback function proc, which will determine if yes or no the given tile meets criteria of search.

Parameters

tile	to start the search from. Upon completion, it will return the tile matching the search. This tile should be directly north of the hole (if any).
radius	How many tiles to search outwards. Note: This is a radius and thus different from the size parameter of the other CircularTileSearch function, which is a diameter.
w	the width of the inner rectangle
h	the height of the inner rectangle
proc	callback testing function pointer.
user_data	to be passed to the callback function. Depends on the implementation

Returns: result of the search

Precondition: proc != nullptr; radius > 0

Definition at line 285 of file map.cpp.

References _tileoffs_by_diagdir, _tileoffs_by_dir, DIAGDIR_BEGIN, DIAGDIR_END, DIR_W, INVALID_TILE, Map::SizeX(), Map::SizeY(), TileX(), TileXY(), TileY(), TileIndexDiffC::x, and TileIndexDiffC::y.

◆ CircularTileSearch() [2/2]

bool CircularTileSearch	(	TileIndex *	tile,
		uint	size,
		TestTileOnSearchProc	proc,
		void *	user_data
	)

Function performing a search around a center tile and going outward, thus in circle.

Although it really is a square search... Every tile will be tested by means of the callback function proc, which will determine if yes or no the given tile meets criteria of search.

Parameters

tile	to start the search from. Upon completion, it will return the tile matching the search
size	number of tiles per side of the desired search area
proc	callback testing function pointer.
user_data	to be passed to the callback function. Depends on the implementation

Returns: result of the search

Precondition: proc != nullptr; size > 0

Definition at line 247 of file map.cpp.

References CircularTileSearch(), DIR_N, and TileAddByDir().

Referenced by ChopLumberMillTrees(), CircularTileSearch(), CmdBuildCanal(), CreateRivers(), FindNearestGoodCoastalTownSpot(), FindStationsNearby(), FlowRiver(), GenerateStationName(), GetDistanceFromNearbyHouse(), GrowTownWithBridge(), LoadTownData(), MakeRiverAndModifyDesertZoneAround(), TownActionBuildStatue(), and TryBuildTransmitter().

◆ DiagdirBetweenTiles()

DiagDirection DiagdirBetweenTiles	(	TileIndex	tile_from,
		TileIndex	tile_to
	)

inline

Determines the DiagDirection to get from one tile to another.

The tiles do not necessarily have to be adjacent.

Parameters

tile_from	Origin tile
tile_to	Destination tile

Returns: DiagDirection from tile_from towards tile_to, or INVALID_DIAGDIR if the tiles are not on an axis

Definition at line 620 of file map_func.h.

References DIAGDIR_NE, DIAGDIR_NW, DIAGDIR_SE, DIAGDIR_SW, INVALID_DIAGDIR, TileX(), and TileY().

Referenced by WaterRegion::ForceUpdate(), and TrainController().

◆ DistanceFromEdge()

uint DistanceFromEdge ( TileIndex tile )

shortest distance from any edge of the map

Parameters

tile	the tile to get the distance from

Returns: the distance from the edge in tiles

Definition at line 206 of file map.cpp.

References Map::SizeX(), Map::SizeY(), TileX(), and TileY().

Referenced by GenerateStationName(), GrayscaleToMapHeights(), GrowTownWithExtraHouse(), IsRoadAllowedHere(), and TownCanBePlacedHere().

◆ DistanceFromEdgeDir()

uint DistanceFromEdgeDir	(	TileIndex	tile,
		DiagDirection	dir
	)

distance from the map edge in given direction

Parameters

tile	the tile to get the distance from
dir	the direction of interest

Returns: the distance from the edge in tiles

Definition at line 223 of file map.cpp.

References _settings_game, GameSettings::construction, DIAGDIR_NE, DIAGDIR_NW, DIAGDIR_SE, DIAGDIR_SW, ConstructionSettings::freeform_edges, Map::MaxX(), Map::MaxY(), TileX(), and TileY().

Referenced by CheckScaledDistanceFromEdge(), and GetOtherAqueductEnd().

◆ DistanceManhattan()

uint DistanceManhattan	(	TileIndex	t0,
		TileIndex	t1
	)

also known as L1-Norm. Is the shortest distance one could go over diagonal tracks (or roads)

The Manhattan distance is the sum of the delta of both the X and Y component. Also known as L1-Norm

Parameters

t0	the start tile
t1	the end tile

Returns: the distance

Definition at line 146 of file map.cpp.

References Delta(), TileX(), and TileY().

Referenced by AfterLoadGame(), AirportGetNearestTown(), CalcClosestTownFromTile(), CalcRaildirsDrawstyle(), CheckSubsidyDistance(), ClosestTownFromTile(), DeleteStaleLinks(), FindDeletedWaypointCloseTo(), FindSubsidyPassengerRoute(), FlowRiver(), FlowsDown(), WaterRegion::ForceUpdate(), GetClosestObject(), GetCountAndDistanceOfClosestInstance(), CargoPacket::GetDistance(), GetDistanceFromNearbyHouse(), GetOrderDistance(), IndustriesScopeResolver::GetVariable(), ObjectScopeResolver::GetVariable(), RoadStopScopeResolver::GetVariable(), HighlightTownLocalAuthorityTiles(), IsCloseToTown(), LinkRefresher::RefreshStats(), VpSelectTilesWithMethod(), VpSetPresizeRange(), and YapfTrainCheckReverse().

◆ DistanceMax()

uint DistanceMax	(	TileIndex	t0,
		TileIndex	t1
	)

also known as L-Infinity-Norm

Also known as L-Infinity-Norm.

Parameters

t0	the start tile
t1	the end tile

Returns: the distance

Definition at line 178 of file map.cpp.

References Delta(), TileX(), and TileY().

Referenced by Station::AddIndustryToDeliver(), CheckIfFarEnoughFromConflictingIndustry(), CheckIfIndustryIsAllowed(), FindStationsNearby(), and GenerateStationName().

◆ DistanceMaxPlusManhattan()

uint DistanceMaxPlusManhattan	(	TileIndex	t0,
		TileIndex	t1
	)

Max + Manhattan.

two times the biggest distance component and once the smallest component.

Parameters

t0	the start tile
t1	the end tile

Returns: the distance

Definition at line 194 of file map.cpp.

References Delta(), TileX(), and TileY().

Referenced by DemandCalculator::CalcDemand(), and MultiCommodityFlow::Dijkstra().

◆ DistanceSquare()

uint DistanceSquare	(	TileIndex	t0,
		TileIndex	t1
	)

euclidian- or L2-Norm squared

The 'Square' distance is the square of the shortest (straight line) distance between the two tiles. Also known as euclidian- or L2-Norm squared.

Parameters

t0	the start tile
t1	the end tile

Returns: the distance

Definition at line 163 of file map.cpp.

References TileX(), and TileY().

Referenced by CmdBuildBridge(), CmdBuildRoad(), CmdBuildTunnel(), FindNearestHangar(), GetOrderDistance(), GetTownRadiusGroup(), IndustriesScopeResolver::GetVariable(), ObjectScopeResolver::GetVariable(), RoadStopScopeResolver::GetVariable(), and PlaceTreeGroupAroundTile().

◆ GetClosestWaterDistance()

uint GetClosestWaterDistance	(	TileIndex	tile,
		bool	water
	)

Finds the distance for the closest tile with water/land given a tile.

Parameters

tile	the tile to find the distance too
water	whether to find water or land

Returns: distance to nearest water (max 0x7F) / land (max 0x1FF; 0x200 if there is no land)

Definition at line 329 of file map.cpp.

References _settings_game, GameSettings::construction, DIAGDIR_BEGIN, DIAGDIR_END, ConstructionSettings::freeform_edges, HasTileWaterGround(), IsInsideMM(), IsTileType(), Map::Iterate(), Map::MaxX(), Map::MaxY(), MP_VOID, MP_WATER, TileX(), TileXY(), and TileY().

Referenced by FindFurthestFromWater(), and IndustriesScopeResolver::GetVariable().

◆ RandomTileSeed()

TileIndex RandomTileSeed ( uint32_t r )

inline

Get a random tile out of a given seed.

Parameters

r	the random 'seed'

Returns: a valid tile

Definition at line 650 of file map_func.h.

References Map::WrapToMap().

Referenced by PlaceTreesRandomly().

◆ TileAdd()

constexpr TileIndex TileAdd	(	TileIndex	tile,
		TileIndexDiff	offset
	)

constexpr

Adds a given offset to a tile.

Parameters

tile	The tile to add an offset to.
offset	The offset to add.

Returns: The resulting tile.

Definition at line 454 of file map_func.h.

Referenced by CalcHeightdiff(), CFollowTrackT< Ttr_type_, VehicleType, T90deg_turns_allowed_, Tmask_reserved_tracks >::CanEnterNewTile(), FindRailStationEnd(), GetOtherAqueductEnd(), GrowTown(), IsNeighborRoadTile(), CYapfReserveTrack< Types >::ReserveRailStationPlatform(), SetRailStationPlatformReservation(), TileAddByDiagDir(), TileAddByDir(), TileAddXY(), and CYapfReserveTrack< Types >::UnreserveSingleTrack().

◆ TileAddByDiagDir()

TileIndex TileAddByDiagDir	(	TileIndex	tile,
		DiagDirection	dir
	)

inline

Adds a DiagDir to a tile.

Parameters

tile	The current tile
dir	The direction in which we want to step

Returns: the moved tile

Definition at line 608 of file map_func.h.

References TileAdd(), and TileOffsByDiagDir().

Referenced by CleanUpRoadBits(), ClearPathReservation(), CmdRemoveSingleSignal(), DrawRoadTypeCatenary(), DrawTile_Road(), CFollowTrackT< Ttr_type_, VehicleType, T90deg_turns_allowed_, Tmask_reserved_tracks >::FollowTileExit(), GrowTownAtRoad(), GrowTownInTile(), GrowTownWithBridge(), GrowTownWithExtraHouse(), GrowTownWithTunnel(), MarkDirtyAdjacentLevelCrossingTiles(), MaskWireBits(), BuildDocksToolbarWindow::OnPlaceObject(), BuildDocksToolbarWindow::OnPlacePresize(), RiverMakeWider(), SetWaterClassDependingOnSurroundings(), TrainController(), TryPathReserve(), and UpdateLevelCrossing().

◆ TileAddByDir()

TileIndex TileAddByDir	(	TileIndex	tile,
		Direction	dir
	)

inline

Adds a Direction to a tile.

Parameters

tile	The current tile
dir	The direction in which we want to step

Returns: the moved tile

Definition at line 596 of file map_func.h.

References TileAdd(), and TileOffsByDir().

Referenced by CalcHeightdiff(), CircularTileSearch(), FindStationsNearby(), and GrowTownInTile().

◆ TileAddWrap()

TileIndex TileAddWrap	(	TileIndex	tile,
		int	addx,
		int	addy
	)

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)

Parameters