Base class for all path types. More...

Detailed Description

Base class for all path types.

Public Member Functions
void	AdvanceState (PathState s)
	Threadsafe increment of the state.

uint	CalculateHScore (GraphNode node)

abstract void	CalculateStep (long targetTick)
	Calculates the path until time has gone past targetTick.

bool	CanTraverse (GraphNode node)
	Returns if the node can be traversed.

void	Claim (System.Object o)
	Claim this path.

virtual void	Cleanup ()
	Always called after the path has been calculated.

virtual string	DebugString (PathLog logMode)
	Returns a debug string for this path.

void	Error ()
	Aborts the path because of an error.

void	ForceLogError (string msg)
	Logs an error and calls Error().

virtual uint	GetConnectionSpecialCost (GraphNode a, GraphNode b, uint currentCost)
	May be called by graph nodes to get a special cost for some connections.

Int3	GetHTarget ()

PathState	GetState ()
	Returns the state of the path in the pathfinding pipeline.

uint	GetTagPenalty (int tag)
	Returns penalty for the given tag.

float	GetTotalLength ()
	Total Length of the path.

uint	GetTraversalCost (GraphNode node)

abstract void	Initialize ()
	Initializes the path.

bool	IsDone ()
	Returns if this path is done calculating.

void	Log (string msg)
	Appends a message to the errorLog.

void	LogError (string msg)
	Appends msg to errorLog and logs msg to the console.

virtual void	OnEnterPool ()
	Called when the path enters the pool.

abstract void	Prepare ()

void	PrepareBase (PathHandler pathHandler)
	Prepares low level path variables for calculation.

void	Release (System.Object o)
	Releases a path claim.

void	ReleaseSilent (System.Object o)
	Releases the path silently.

virtual void	Reset ()
	Reset all values to their default values.

virtual void	ReturnPath ()
	Calls callback to return the calculated path.

IEnumerator	WaitForPath ()
	Waits until this path has been calculated and returned.

Public Attributes
OnPathDelegate	callback
	Callback to call when the path is complete.

System.DateTime	callTime
	When the call was made to start the pathfinding for this path.

float	duration
	The duration of this path in ms.

int	enabledTags = -1
	Which graph tags are traversable.

int	height
	Height of the character.

Heuristic	heuristic
	Determines which heuristic to use.

float	heuristicScale = 1F
	Scale of the heuristic values.

OnPathDelegate	immediateCallback
	Immediate callback to call when the path is complete.

Path	next
	The next path to be searched.

NNConstraint	nnConstraint = PathNNConstraint.Default
	Constraint for how to search for nodes.

List< GraphNode >	path
	Holds the path as a Node array.

PathHandler	pathHandler
	Data for the thread calculating this path.

ushort	pathID
	ID of this path.

int	radius
	Radius for the unit searching for the path.

bool	recycled = false
	True if the path is currently recycled (i.e in the path pool).

int	searchedNodes
	Number of nodes this path has searched.

int	searchIterations = 0

int	speed
	Speed of the character.

int	turnRadius
	Turning radius of the character.

List< Vector3 >	vectorPath
	Holds the (perhaps post processed) path as a Vector3 array.

int	walkabilityMask = -1
	A mask for defining what type of ground a unit can traverse, not used in any default standard graph.

Protected Member Functions
bool	HasExceededTime (int searchedNodes, long targetTime)

abstract void	Recycle ()
	Recycle the path.

virtual void	Trace (PathNode from)
	Traces the calculated path from the end node to the start.

Protected Attributes
PathNode	currentR
	The node currently being processed.

bool	hasBeenReset = false
	True if the Reset function has been called.

Int3	hTarget
	Target to use for H score calculation.

GraphNode	hTargetNode

int[]	internalTagPenalties = null
	The tag penalties that are actually used.

int[]	manualTagPenalties = null
	Tag penalties set by other scripts.

float	maxFrameTime
	The max number of milliseconds per iteration (frame, in case of non-multithreading)

Properties
PathCompleteState	CompleteState `[get, set]`
	Current state of the path.

bool	error `[get]`
	If the path failed, this is true.

string	errorLog `[get]`
	Log messages with info about eventual errors.

virtual bool	FloodingPath `[get]`

int[]	tagPenalties `[get, set]`
	Penalties for each tag.

Private Member Functions
void	ErrorCheck ()
	Does some error checking.

Private Attributes
string	_errorLog = ""
	Additional info on what went wrong.

GraphNode[]	_path

Vector3[]	_vectorPath

List< System.Object >	claimed = new List<System.Object>()
	List of claims on this path with reference objects.

PathCompleteState	pathCompleteState
	Current state of the path.

bool	releasedNotSilent = false
	True if the path has been released with a non-silent call yet.

PathState	state

System.Object	stateLock = new object()

Static Private Attributes
static readonly int[]	ZeroTagPenalties = new int[32]

Member Function Documentation

void AdvanceState ( PathState s )

Threadsafe increment of the state.

uint CalculateHScore ( GraphNode node )

abstract void CalculateStep ( long targetTick )

pure virtual

Calculates the path until time has gone past targetTick.

Implemented in MultiTargetPath, ABPath, RandomPath, FloodPath, ConstantPath, and FloodPathTracer.

bool CanTraverse ( GraphNode node )

Returns if the node can be traversed.

This per default equals to if the node is walkable and if the node's tag is included in enabledTags

void Claim ( System.Object o )

Claim this path.

A claim on a path will ensure that it is not recycled. If you are using a path, you will want to claim it when you first get it and then release it when you will not use it anymore. When there are no claims on the path, it will be recycled and put in a pool.

See Also: Release; Recycle

virtual void Cleanup ( )

virtual

Always called after the path has been calculated.

Guaranteed to be called before other paths have been calculated on the same thread. Use for cleaning up things like node tagging and similar.

Reimplemented in ABPath, and ConstantPath.

virtual string DebugString ( PathLog logMode )

virtual

Returns a debug string for this path.

Reimplemented in MultiTargetPath, and ABPath.

void Error ( )

Aborts the path because of an error.

Sets error to true. This function is called when an error has ocurred (e.g a valid path could not be found).

See Also: LogError

void ErrorCheck ( )

private

Does some error checking.

Makes sure the user isn't using old code paths and that no major errors have been done.

Exceptions

An	exception if any errors are found

void ForceLogError ( string msg )

Logs an error and calls Error().

This is called only if something is very wrong or the user is doing something he/she really should not be doing.

virtual uint GetConnectionSpecialCost	(	GraphNode	a,
		GraphNode	b,
		uint	currentCost
	)

virtual

May be called by graph nodes to get a special cost for some connections.

Nodes may call it when PathNode.flag2 is set to true, for example mesh nodes, which have a very large area can be marked on the start and end nodes, this method will be called to get the actual cost for moving from the start position to its neighbours instead of as would otherwise be the case, from the start node's position to its neighbours. The position of a node and the actual start point on the node can vary quite a lot.

The default behaviour of this method is to return the previous cost of the connection, essentiall making no change at all.

This method should return the same regardless of the order of a and b. That is f(a,b) == f(b,a) should hold.

Parameters

a	Moving from this node
b	Moving to this node
currentCost	The cost of moving between the nodes. Return this value if there is no meaningful special cost to return.

Reimplemented in ABPath.

Int3 GetHTarget ( )

PathState GetState ( )

Returns the state of the path in the pathfinding pipeline.

uint GetTagPenalty ( int tag )

Returns penalty for the given tag.

Parameters

tag	A value between 0 (inclusive) and 32 (exclusive).

float GetTotalLength ( )

Total Length of the path.

Calculates the total length of the vectorPath. Cache this rather than call this function every time since it will calculate the length every time, not just return a cached value.

Returns: Total length of vectorPath, if vectorPath is null positive infinity is returned.

uint GetTraversalCost ( GraphNode node )

bool HasExceededTime	(	int	searchedNodes,
		long	targetTime
	)

protected

abstract void Initialize ( )

pure virtual

Initializes the path.

Sets up the open list and adds the first node to it

Implemented in MultiTargetPath, ABPath, RandomPath, FloodPath, ConstantPath, and FloodPathTracer.

bool IsDone ( )

Returns if this path is done calculating.

Returns: If CompleteState is not PathCompleteState.NotCalculated.

Note: The path might not have been returned yet.

Since: Added in 3.0.8

See Also: Seeker.IsDone

void Log ( string msg )

Appends a message to the errorLog.

Nothing is logged to the console.

Note: If AstarPath.logPathResults is PathLog.None and this is a standalone player, nothing will be logged as an optimization.

void LogError ( string msg )

Appends msg to errorLog and logs msg to the console.

Debug.Log call is only made if AstarPath.logPathResults is not equal to None and not equal to InGame. Consider calling Error() along with this call.

virtual void OnEnterPool ( )

virtual

Called when the path enters the pool.

This method should release e.g pooled lists and other pooled resources The base version of this method releases vectorPath and path lists. Reset() will be called after this function, not before.

Warning: Do not call this function manually.

Reimplemented in MultiTargetPath, and ConstantPath.

abstract void Prepare ( )

pure virtual

Implemented in MultiTargetPath, ABPath, RandomPath, FloodPath, and ConstantPath.

void PrepareBase ( PathHandler pathHandler )

Prepares low level path variables for calculation.

Called before a path search will take place. Always called before the Prepare, Initialize and CalculateStep functions

abstract void Recycle ( )

protectedpure virtual

Recycle the path.

Calling this means that the path and any variables on it are not needed anymore and the path can be pooled. All path data will be reset. Implement this in inheriting path types to support recycling of paths.

public override void Recycle () {
    //Recycle the Path (<Path> should be replaced by the path type it is implemented in)
    PathPool<Path>.Recycle (this);
}

Warning: Do not call this function directly, instead use the Claim and Release functions.

See Also: Pathfinding.PathPool; Reset; Claim; Release

Implemented in ABPath, FloodPath, MultiTargetPath, ConstantPath, RandomPath, FloodPathTracer, and FleePath.

void Release ( System.Object o )

Releases a path claim.

Removes the claim of the path by the specified object. When the claim count reaches zero, the path will be recycled, all variables will be cleared and the path will be put in a pool to be used again. This is great for memory since less allocations are made.

See Also: Claim

void ReleaseSilent ( System.Object o )

Releases the path silently.

This will remove the claim by the specified object, but the path will not be recycled if the claim count reches zero unless a Release call (not silent) has been made earlier. This is used by the internal pathfinding components such as Seeker and AstarPath so that they will not recycle paths. This enables users to skip the claim/release calls if they want without the path being recycled by the Seeker or AstarPath.

virtual void Reset ( )

virtual

Reset all values to their default values.

Note: All inheriting path types (e.g ConstantPath, RandomPath, etc.) which declare their own variables need to override this function, resetting ALL their variables to enable recycling of paths. If this is not done, trying to use that path type for pooling might result in weird behaviour. The best way is to reset to default values the variables declared in the extended path type and then call this base function in inheriting types with base.Reset ().

Warning: This function should not be called manually.

Reimplemented in ABPath, ConstantPath, FloodPath, FloodPathTracer, and RandomPath.

virtual void ReturnPath ( )

virtual

Calls callback to return the calculated path.

See Also: callback

Reimplemented in MultiTargetPath, and RandomPath.

virtual void Trace ( PathNode from )

protectedvirtual

Traces the calculated path from the end node to the start.

This will build an array (path) of the nodes this path will pass through and also set the vectorPath array to the path arrays positions. Assumes the vectorPath and path are empty and not null (which will be the case for a correctly initialized path).

Reimplemented in MultiTargetPath.

IEnumerator WaitForPath ( )

Waits until this path has been calculated and returned.

Allows for very easy scripting.

//In an IEnumerator function
Path p = Seeker.StartPath (transform.position, transform.position + Vector3.forward * 10);
yield return StartCoroutine (p.WaitForPath ());
//The path is calculated at this stage

Note: Do not confuse this with AstarPath.WaitForPath. This one will wait using yield until it has been calculated while AstarPath.WaitForPath will halt all operations until the path has been calculated.

Exceptions

System.InvalidOperationException if the path is not started. Send the path to Seeker.StartPath or AstarPath.StartPath before calling this function.

See Also: AstarPath.WaitForPath

Member Data Documentation

string _errorLog = ""

private

Additional info on what went wrong.

See Also: error

GraphNode [] _path

private

Vector3 [] _vectorPath

private

OnPathDelegate callback

Callback to call when the path is complete.

This is usually sent to the Seeker component which post processes the path and then calls a callback to the script which requested the path

System.DateTime callTime

When the call was made to start the pathfinding for this path.

List<System.Object> claimed = new List<System.Object>()

private

List of claims on this path with reference objects.

PathNode currentR

protected

The node currently being processed.

float duration

The duration of this path in ms.

How long it took to calculate the path The number of frames/iterations this path has executed. This is the number of frames when not using multithreading. When using multithreading, this value is quite irrelevant

int enabledTags = -1

Which graph tags are traversable.

This is a bitmask so -1 = all bits set = all tags traversable. For example, to set bit 5 to true, you would do

myPath.enabledTags |= 1 << 5;

To set it to false, you would do

myPath.enabledTags &= ~(1 << 5);

The Seeker has a popup field where you can set which tags to use.

Note: If you are using a Seeker. The Seeker will set this value to what is set in the inspector field on StartPath. So you need to change the Seeker value via script, not set this value if you want to change it via script.

See Also: CanTraverse

bool hasBeenReset = false

protected

True if the Reset function has been called.

Used to allert users when they are doing it wrong.

int height

Height of the character.

Not used currently

Heuristic heuristic

Determines which heuristic to use.

float heuristicScale = 1F

Scale of the heuristic values.

Int3 hTarget

protected

Target to use for H score calculation.

Used alongside hTarget. Target to use for H score calculations.

See Also: Pathfinding.Node.H

GraphNode hTargetNode

protected

OnPathDelegate immediateCallback

Immediate callback to call when the path is complete.

Warning: This may be called from a separate thread. Usually you do not want to use this one.

See Also: callback

int [] internalTagPenalties = null

protected

The tag penalties that are actually used.

If manualTagPenalties is null, this will be ZeroTagPenalties

See Also: tagPenalties

int [] manualTagPenalties = null

protected

Tag penalties set by other scripts.

See Also: tagPenalties

float maxFrameTime

protected

The max number of milliseconds per iteration (frame, in case of non-multithreading)

Path next

The next path to be searched.

Linked list implementation.

Warning: You should never change this if you do not know what you are doing

NNConstraint nnConstraint = PathNNConstraint.Default

Constraint for how to search for nodes.

List<GraphNode> path

Holds the path as a Node array.

All nodes the path traverses. This might not be the same as all nodes the smoothed path traverses.

PathCompleteState pathCompleteState

private

Current state of the path.

See Also: CompleteState

PathHandler pathHandler

Data for the thread calculating this path.

ushort pathID

ID of this path.

Used to distinguish between different paths

int radius

Radius for the unit searching for the path.

Note: Not used by any built-in pathfinders. These common name variables are put here because it is a lot faster to access fields than, for example make use of a lookup table (e.g dictionary). Or having to cast to another path type for acess.

bool recycled = false

True if the path is currently recycled (i.e in the path pool).

Do not set this value. Only read. It is used internally.

bool releasedNotSilent = false

private

True if the path has been released with a non-silent call yet.

See Also: Release; ReleaseSilent; Claim

int searchedNodes

Number of nodes this path has searched.

int searchIterations = 0

int speed

Speed of the character.

Not used currently

PathState state

private

System.Object stateLock = new object()

private

int turnRadius

Turning radius of the character.

Not used currently

List<Vector3> vectorPath

Holds the (perhaps post processed) path as a Vector3 array.

int walkabilityMask = -1

A mask for defining what type of ground a unit can traverse, not used in any default standard graph.

See Also: enabledTags

Note: Not used by any built-in pathfinders. These variables are put here because it is a lot faster to access fields than, for example make use of a lookup table (e.g dictionary)

readonly int [] ZeroTagPenalties = new int[32]

staticprivate

Property Documentation

PathCompleteState CompleteState

getset

Current state of the path.

bool error

get

If the path failed, this is true.

See Also: errorLog

string errorLog

get

Log messages with info about eventual errors.

virtual bool FloodingPath

get

int [] tagPenalties

getset

Penalties for each tag.

Tag 0 which is the default tag, will have added a penalty of tagPenalties[0]. These should only be positive values since the A* algorithm cannot handle negative penalties.

Note: This array will never be null. If you try to set it to null or with a lenght which is not 32. It will be set to "new int[0]".; If you are using a Seeker. The Seeker will set this value to what is set in the inspector field on StartPath. So you need to change the Seeker value via script, not set this value if you want to change it via script.

See Also: Seeker.tagPenalties

The documentation for this class was generated from the following file:

/Users/arong/Unity/a-pathfinding-project/Assets/AstarPathfindingProject/Core/Path.cs

Detailed Description

Public Member Functions

Public Attributes

Protected Member Functions

Protected Attributes

Properties

Private Member Functions

Private Attributes

Static Private Attributes

Member Function Documentation

Member Data Documentation

Property Documentation