This file has the header for AyStar. More...

#include "../track_func.h"
#include "../misc/hashtable.hpp"
#include "../misc/binaryheap.hpp"
#include "../misc/dbg_helpers.h"
#include "yapf/nodelist.hpp"
#include "yapf/yapf_node.hpp"

Data Structures
struct	PathNode

struct	AyStar
	AyStar search algorithm struct. More...

Typedefs
using	AyStarNode = CYapfNodeKeyTrackDir

typedef int32_t	AyStar_EndNodeCheck(const AyStar aystar, const PathNode current)
	Check whether the end-tile is found. More...

typedef int32_t	AyStar_CalculateG(AyStar aystar, AyStarNode current, PathNode *parent)
	Calculate the G-value for the AyStar algorithm. More...

typedef int32_t	AyStar_CalculateH(AyStar aystar, AyStarNode current, PathNode *parent)
	Calculate the H-value for the AyStar algorithm. More...

typedef void	AyStar_GetNeighbours(AyStar aystar, PathNode current)
	This function requests the tiles around the current tile and put them in #neighbours. More...

typedef void	AyStar_FoundEndNode(AyStar aystar, PathNode current)
	If the End Node is found, this function is called. More...

Enumerations
enum	AystarStatus { AYSTAR_FOUND_END_NODE , AYSTAR_EMPTY_OPENLIST , AYSTAR_STILL_BUSY , AYSTAR_NO_PATH , AYSTAR_LIMIT_REACHED , AYSTAR_DONE }
	Return status of AyStar methods. More...

Functions
bool	CheckIgnoreFirstTile (const PathNode *node)

Variables
static const int	AYSTAR_DEF_MAX_SEARCH_NODES = 10000
	Reference limit for AyStar::max_search_nodes.

static const int	AYSTAR_INVALID_NODE = -1
	Item is not valid (for example, not walkable).

Detailed Description

This file has the header for AyStar.

AyStar is a fast path finding routine and is used for things like AI path finding and Train path finding. For more information about AyStar (A* Algorithm), you can look at http://en.wikipedia.org/wiki/A-star_search_algorithm.

Definition in file aystar.h.

Typedef Documentation

◆ AyStar_CalculateG

typedef int32_t AyStar_CalculateG(AyStar *aystar, AyStarNode *current, PathNode *parent)

Calculate the G-value for the AyStar algorithm.

Returns

G value of the node:

AYSTAR_INVALID_NODE : indicates an item is not valid (e.g.: unwalkable)
Any value >= 0 : the g-value for this tile

Definition at line 73 of file aystar.h.

◆ AyStar_CalculateH

typedef int32_t AyStar_CalculateH(AyStar *aystar, AyStarNode *current, PathNode *parent)

Calculate the H-value for the AyStar algorithm.

Mostly, this must return the distance (Manhattan way) between the current point and the end point.

Returns: The h-value for this tile (any value >= 0)

Definition at line 80 of file aystar.h.

◆ AyStar_EndNodeCheck

typedef int32_t AyStar_EndNodeCheck(const AyStar *aystar, const PathNode *current)

Check whether the end-tile is found.

Parameters

aystar	AyStar search algorithm data.
current	Node to exam one.

Note: The 2nd parameter should be #OpenListNode, and not #AyStarNode. #AyStarNode is part of #OpenListNode and so it could be accessed without any problems. The good part about #OpenListNode is, and how AIs use it, that you can access the parent of the current node, and so check if you, for example don't try to enter the file tile with a 90-degree curve. So please, leave this an #OpenListNode, it works just fine.

Returns

Status of the node:

AYSTAR_FOUND_END_NODE : indicates this is the end tile
AYSTAR_DONE : indicates this is not the end tile (or direction was wrong)

Definition at line 65 of file aystar.h.

◆ AyStar_FoundEndNode

typedef void AyStar_FoundEndNode(AyStar *aystar, PathNode *current)

If the End Node is found, this function is called.

It can do, for example, calculate the route and put that in an array.

Definition at line 93 of file aystar.h.

◆ AyStar_GetNeighbours

typedef void AyStar_GetNeighbours(AyStar *aystar, PathNode *current)

This function requests the tiles around the current tile and put them in #neighbours.

#neighbours is never reset, so if you are not using directions, just leave it alone.

Warning: Never add more #neighbours than memory allocated for it.

Definition at line 87 of file aystar.h.

Enumeration Type Documentation

◆ AystarStatus

enum AystarStatus

Return status of AyStar methods.

Enumerator
AYSTAR_FOUND_END_NODE	An end node was found.
AYSTAR_EMPTY_OPENLIST	All items are tested, and no path has been found.
AYSTAR_STILL_BUSY	Some checking was done, but no path found yet, and there are still items left to try.
AYSTAR_NO_PATH	No path to the goal was found.
AYSTAR_LIMIT_REACHED	The AyStar::max_search_nodes limit has been reached, aborting search.
AYSTAR_DONE	Not an end-tile, or wrong direction.

Definition at line 31 of file aystar.h.

Data Structures

Typedefs

Enumerations

Functions

Variables