Handles path calls for a single unit. More...

Detailed Description

Handles path calls for a single unit.

This is a component which is meant to be attached to a single unit (AI, Robot, Player, whatever) to handle its pathfinding calls. It also handles post-processing of paths using modifiers.

See also: Searching for paths; Using Modifiers

Public Types
enum	ModifierPass { PreProcess, PostProcess = 2 }

Public Member Functions
	Seeker ()

void	CancelCurrentPathRequest (bool pool=true)
	Stop calculating the current path request. More...

void	DeregisterModifier (IPathModifier modifier)
	Called by modifiers when they are disabled or destroyed. More...

Path	GetCurrentPath ()
	Path that is currently being calculated or was last calculated. More...

ABPath	GetNewPath (Vector3 start, Vector3 end)
	Returns a new path instance. More...

bool	IsDone ()
	Is the current path done calculating. More...

void	OnDestroy ()
	Cleans up some variables. More...

void	OnDrawGizmos ()
	Draws gizmos for the Seeker. More...

void	PostProcess (Path path)
	Post Processes the path. More...

void	RegisterModifier (IPathModifier modifier)
	Called by modifiers to register themselves. More...

void	ReleaseClaimedPath ()
	Releases the path used for gizmos (if any). More...

void	RunModifiers (ModifierPass pass, Path path)
	Runs modifiers on a path. More...

MultiTargetPath	StartMultiTargetPath (Vector3 start, Vector3[] endPoints, bool pathsForAll, OnPathDelegate callback=null, int graphMask=-1)
	Starts a Multi Target Path from one start point to multiple end points. More...

MultiTargetPath	StartMultiTargetPath (Vector3[] startPoints, Vector3 end, bool pathsForAll, OnPathDelegate callback=null, int graphMask=-1)
	Starts a Multi Target Path from multiple start points to a single target point. More...

MultiTargetPath	StartMultiTargetPath (MultiTargetPath p, OnPathDelegate callback=null, int graphMask=-1)
	Starts a Multi Target Path. More...

Path	StartPath (Vector3 start, Vector3 end)
	Call this function to start calculating a path. More...

Path	StartPath (Vector3 start, Vector3 end, OnPathDelegate callback)
	Call this function to start calculating a path. More...

Path	StartPath (Vector3 start, Vector3 end, OnPathDelegate callback, GraphMask graphMask)
	Call this function to start calculating a path. More...

Path	StartPath (Path p, OnPathDelegate callback=null)
	Call this function to start calculating a path. More...

Path	StartPath (Path p, OnPathDelegate callback, GraphMask graphMask)
	Call this function to start calculating a path. More...

Public Attributes
bool	detailedGizmos
	Enables drawing of the non-postprocessed path using Gizmos. More...

bool	drawGizmos = true
	Enables drawing of the last calculated path using Gizmos. More...

GraphMask	graphMask = GraphMask.everything
	Graphs that this Seeker can use. More...

OnPathDelegate	pathCallback
	Callback for when a path is completed. More...

OnPathDelegate	postProcessPath
	Called after a path has been calculated, right before modifiers are executed. More...

OnPathDelegate	preProcessPath
	Called before pathfinding is started. More...

StartEndModifier	startEndModifier = new StartEndModifier()
	Path modifier which tweaks the start and end points of a path. More...

int []	tagPenalties = new int[32]
	Penalties for each tag. More...

int	traversableTags = -1
	The tags which the Seeker can traverse. More...

Protected Member Functions
override void	Awake ()
	Initializes a few variables. More...

override int	OnUpgradeSerializedData (int version, bool unityThread)
	Handle serialization backwards compatibility. More...

Protected Member Functions inherited from VersionedMonoBehaviour
virtual void	Reset ()
	Handle serialization backwards compatibility. More...

Protected Attributes
uint	lastPathID
	The path ID of the last path queried. More...

Path	path
	The current path. More...

Private Member Functions
void	OnMultiPathComplete (Path p)
	Called once for a MultiTargetPath. More...

void	OnPartialPathComplete (Path p)
	Called for each path in a MultiTargetPath. More...

void	OnPathComplete (Path path)
	Called when a path has completed. More...

void	OnPathComplete (Path p, bool runModifiers, bool sendCallbacks)
	Called when a path has completed. More...

void	StartPathInternal (Path p, OnPathDelegate callback)
	Internal method to start a path and mark it as the currently active path. More...

Private Attributes
int	graphMaskCompatibility = -1
	Used for serialization backwards compatibility. More...

List< GraphNode >	lastCompletedNodePath
	Used for drawing gizmos. More...

List< Vector3 >	lastCompletedVectorPath
	Used for drawing gizmos. More...

readonly List< IPathModifier >	modifiers = new List<IPathModifier>()
	Internal list of all modifiers. More...

readonly OnPathDelegate	onPartialPathDelegate
	Cached delegate to avoid allocating one every time a path is started. More...

readonly OnPathDelegate	onPathDelegate
	Cached delegate to avoid allocating one every time a path is started. More...

Path	prevPath
	Previous path. More...

OnPathDelegate	tmpPathCallback
	Temporary callback only called for the current path. More...

Member Enumeration Documentation

◆ ModifierPass

enum ModifierPass

strong

Enumerator
PreProcess
PostProcess

Constructor & Destructor Documentation

◆ Seeker()

Seeker ( )

Member Function Documentation

◆ Awake()

override void Awake ( )

protectedvirtual

Initializes a few variables.

Reimplemented from VersionedMonoBehaviour.

◆ CancelCurrentPathRequest()

void CancelCurrentPathRequest ( bool pool = true )

Stop calculating the current path request.

If this Seeker is currently calculating a path it will be canceled. The callback (usually to a method named OnPathComplete) will soon be called with a path that has the 'error' field set to true.

This does not stop the character from moving, it just aborts the path calculation.

Parameters

pool	If true then the path will be pooled when the pathfinding system is done with it.

◆ DeregisterModifier()

void DeregisterModifier ( IPathModifier modifier )

Called by modifiers when they are disabled or destroyed.

◆ GetCurrentPath()

Path GetCurrentPath ( )

Path that is currently being calculated or was last calculated.

You should rarely have to use this. Instead get the path when the path callback is called.

See also: pathCallback

◆ GetNewPath()

ABPath GetNewPath	(	Vector3	start,
		Vector3	end
	)

Returns a new path instance.

The path will be taken from the path pool if path recycling is turned on.
This path can be sent to #StartPath(Path,OnPathDelegate,int) with no change, but if no change is required StartPath(Vector3,Vector3,OnPathDelegate) does just that.

var seeker = GetComponent<Seeker>();
Path p = seeker.GetNewPath (transform.position, transform.position+transform.forward*100);
// Disable heuristics on just this path for example
p.heuristic = Heuristic.None;
seeker.StartPath (p, OnPathComplete);

Deprecated:: Use ABPath.Construct(start, end, null) instead.

◆ IsDone()

bool IsDone ( )

Is the current path done calculating.

Returns true if the current path has been returned or if the path is null.

Note: Do not confuse this with Pathfinding.Path.IsDone. They usually return the same value, but not always since the path might be completely calculated, but it has not yet been processed by the Seeker.

Since: Added in 3.0.8

Version: Behaviour changed in 3.2

◆ OnDestroy()

void OnDestroy ( )

Cleans up some variables.

Releases any eventually claimed paths. Calls OnDestroy on the startEndModifier.

See also: ReleaseClaimedPath; startEndModifier

◆ OnDrawGizmos()

void OnDrawGizmos ( )

Draws gizmos for the Seeker.

◆ OnMultiPathComplete()

void OnMultiPathComplete ( Path p )

private

Called once for a MultiTargetPath.

Only returns the path, does not post process.

A* Pro Feature:: This is an A* Pathfinding Project Pro feature only. This function/class/variable might not exist in the Free version of the A* Pathfinding Project or the functionality might be limited
The Pro version can be bought here

◆ OnPartialPathComplete()

void OnPartialPathComplete ( Path p )

private

Called for each path in a MultiTargetPath.

Only post processes the path, does not return it.

A* Pro Feature:: This is an A* Pathfinding Project Pro feature only. This function/class/variable might not exist in the Free version of the A* Pathfinding Project or the functionality might be limited
The Pro version can be bought here

◆ OnPathComplete() [1/2]

void OnPathComplete ( Path path )

private

Called when a path has completed.

This should have been implemented as optional parameter values, but that didn't seem to work very well with delegates (the values weren't the default ones)

See also: OnPathComplete(Path,bool,bool)

◆ OnPathComplete() [2/2]

void OnPathComplete	(	Path	p,
		bool	runModifiers,
		bool	sendCallbacks
	)

private

Called when a path has completed.

Will post process it and return it by calling tmpPathCallback and pathCallback

◆ OnUpgradeSerializedData()

override int OnUpgradeSerializedData	(	int	version,
		bool	unityThread
	)

protectedvirtual

Handle serialization backwards compatibility.

Reimplemented from VersionedMonoBehaviour.

◆ PostProcess()

void PostProcess ( Path path )

Post Processes the path.

This will run any modifiers attached to this GameObject on the path. This is identical to calling RunModifiers(ModifierPass.PostProcess, path)

See also: RunModifiers

Since: Added in 3.2

◆ RegisterModifier()

void RegisterModifier ( IPathModifier modifier )

Called by modifiers to register themselves.

◆ ReleaseClaimedPath()

void ReleaseClaimedPath ( )

Releases the path used for gizmos (if any).

The seeker keeps the latest path claimed so it can draw gizmos. In some cases this might not be desireable and you want it released. In that case, you can call this method to release it (not that path gizmos will then not be drawn).

If you didn't understand anything from the description above, you probably don't need to use this method.

See also: Pooling

◆ RunModifiers()

void RunModifiers	(	ModifierPass	pass,
		Path	path
	)

Runs modifiers on a path.

◆ StartMultiTargetPath() [1/3]

MultiTargetPath StartMultiTargetPath	(	Vector3	start,
		Vector3 []	endPoints,
		bool	pathsForAll,
		OnPathDelegate	callback = `null`,
		int	graphMask = `-1`
	)

Starts a Multi Target Path from one start point to multiple end points.

A Multi Target Path will search for all the end points in one search and will return all paths if pathsForAll is true, or only the shortest one if pathsForAll is false.

Parameters

start	The start point of the path
endPoints	The end points of the path
pathsForAll	Indicates whether or not a path to all end points should be searched for or only to the closest one
callback	The function to call when the path has been calculated
graphMask	Mask used to specify which graphs should be searched for close nodes. See Pathfinding.NNConstraint.graphMask.

callback and pathCallback will be called when the path has completed. Callback will not be called if the path is canceled (e.g when a new path is requested before the previous one has completed)

A* Pro Feature:: This is an A* Pathfinding Project Pro feature only. This function/class/variable might not exist in the Free version of the A* Pathfinding Project or the functionality might be limited
The Pro version can be bought here

See also: Pathfinding.MultiTargetPath; Example of how to use multi-target-paths

◆ StartMultiTargetPath() [2/3]

MultiTargetPath StartMultiTargetPath	(	Vector3 []	startPoints,
		Vector3	end,
		bool	pathsForAll,
		OnPathDelegate	callback = `null`,
		int	graphMask = `-1`
	)

Starts a Multi Target Path from multiple start points to a single target point.

A Multi Target Path will search from all start points to the target point in one search and will return all paths if pathsForAll is true, or only the shortest one if pathsForAll is false.

Parameters

startPoints	The start points of the path
end	The end point of the path
pathsForAll	Indicates whether or not a path from all start points should be searched for or only to the closest one
callback	The function to call when the path has been calculated
graphMask	Mask used to specify which graphs should be searched for close nodes. See Pathfinding.NNConstraint.graphMask.

callback and pathCallback will be called when the path has completed. Callback will not be called if the path is canceled (e.g when a new path is requested before the previous one has completed)

A* Pro Feature:: This is an A* Pathfinding Project Pro feature only. This function/class/variable might not exist in the Free version of the A* Pathfinding Project or the functionality might be limited
The Pro version can be bought here

See also: Pathfinding.MultiTargetPath; Example of how to use multi-target-paths

◆ StartMultiTargetPath() [3/3]

MultiTargetPath StartMultiTargetPath	(	MultiTargetPath	p,
		OnPathDelegate	callback = `null`,
		int	graphMask = `-1`
	)

Starts a Multi Target Path.

Takes a MultiTargetPath and wires everything up for it to send callbacks to the seeker for post-processing.

Parameters

p	The path to start calculating
callback	The function to call when the path has been calculated
graphMask	Mask used to specify which graphs should be searched for close nodes. See Pathfinding.NNConstraint.graphMask.

callback and pathCallback will be called when the path has completed. Callback will not be called if the path is canceled (e.g when a new path is requested before the previous one has completed)

A* Pro Feature:: This is an A* Pathfinding Project Pro feature only. This function/class/variable might not exist in the Free version of the A* Pathfinding Project or the functionality might be limited
The Pro version can be bought here

See also: Pathfinding.MultiTargetPath; Example of how to use multi-target-paths

Version: Since 3.8.3 calling this method behaves identically to calling StartPath with a MultiTargetPath.; Since 3.8.3 this method also sets enabledTags and tagPenalties on the path object.

Deprecated:: You can use StartPath instead of this method now. It will behave identically.

◆ StartPath() [1/5]

Path StartPath	(	Vector3	start,
		Vector3	end
	)

Call this function to start calculating a path.

Since this method does not take a callback parameter, you should set the pathCallback field before calling this method.

Parameters

start	The start point of the path
end	The end point of the path

◆ StartPath() [2/5]

Path StartPath	(	Vector3	start,
		Vector3	end,
		OnPathDelegate	callback
	)

Call this function to start calculating a path.

Parameters

start	The start point of the path
end	The end point of the path
callback	The function to call when the path has been calculated

callback will be called when the path has completed. Callback will not be called if the path is canceled (e.g when a new path is requested before the previous one has completed)

◆ StartPath() [3/5]

Path StartPath	(	Vector3	start,
		Vector3	end,
		OnPathDelegate	callback,
		GraphMask	graphMask
	)

Call this function to start calculating a path.

Parameters

start	The start point of the path
end	The end point of the path
callback	The function to call when the path has been calculated
graphMask	Mask used to specify which graphs should be searched for close nodes. See Pathfinding.NNConstraint.graphMask. This will override graphMask for this path request.

callback will be called when the path has completed. Callback will not be called if the path is canceled (e.g when a new path is requested before the previous one has completed)

◆ StartPath() [4/5]

Path StartPath	(	Path	p,
		OnPathDelegate	callback = `null`
	)

Call this function to start calculating a path.

Parameters

p	The path to start calculating
callback	The function to call when the path has been calculated

The callback will be called when the path has been calculated (which may be several frames into the future). The callback will not be called if a new path request is started before this path request has been calculated.

Version: Since 3.8.3 this method works properly if a MultiTargetPath is used. It now behaves identically to the StartMultiTargetPath(MultiTargetPath) method.; Since 4.1.x this method will no longer overwrite the graphMask on the path unless it is explicitly passed as a parameter (see other overloads of this method).

◆ StartPath() [5/5]

Path StartPath	(	Path	p,
		OnPathDelegate	callback,
		GraphMask	graphMask
	)

Call this function to start calculating a path.

Parameters

p	The path to start calculating
callback	The function to call when the path has been calculated
graphMask	Mask used to specify which graphs should be searched for close nodes. See Pathfinding.GraphMask. This will override graphMask for this path request.

The callback will be called when the path has been calculated (which may be several frames into the future). The callback will not be called if a new path request is started before this path request has been calculated.

Version: Since 3.8.3 this method works properly if a MultiTargetPath is used. It now behaves identically to the StartMultiTargetPath(MultiTargetPath) method.

◆ StartPathInternal()

void StartPathInternal	(	Path	p,
		OnPathDelegate	callback
	)

private

Internal method to start a path and mark it as the currently active path.

Member Data Documentation

◆ detailedGizmos

bool detailedGizmos

Enables drawing of the non-postprocessed path using Gizmos.

The path will show up in orange.

Requires that drawGizmos is true.

This will show the path before any post processing such as smoothing is applied.

See also: drawGizmos; OnDrawGizmos

◆ drawGizmos

bool drawGizmos = true

Enables drawing of the last calculated path using Gizmos.

The path will show up in green.

See also: OnDrawGizmos

◆ graphMask

GraphMask graphMask = GraphMask.everything

Graphs that this Seeker can use.

This field determines which graphs will be considered when searching for the start and end nodes of a path. It is useful in numerous situations, for example if you want to make one graph for small units and one graph for large units.

This is a bitmask so if you for example want to make the agent only use graph index 3 then you can set this to:

seeker.graphMask = 1 << 3;

See also: Bitmask Tutorial

Note that this field only stores which graph indices that are allowed. This means that if the graphs change their ordering then this mask may no longer be correct.

If you know the name of the graph you can use the Pathfinding.GraphMask.FromGraphName method:

        GraphMask mask1 = GraphMask.FromGraphName("My Grid Graph");
        GraphMask mask2 = GraphMask.FromGraphName("My Other Grid Graph");
        NNConstraint nn = NNConstraint.Default;
        nn.graphMask = mask1 | mask2;
        // Find the node closest to somePoint which is either in 'My Grid Graph' OR in 'My Other Grid Graph'
        var info = AstarPath.active.GetNearest(somePoint, nn);

Some overloads of the StartPath methods take a graphMask parameter. If those overloads are used then they will override the graph mask for that path request.

See also: Multiple agent types

◆ graphMaskCompatibility

int graphMaskCompatibility = -1

private

Used for serialization backwards compatibility.

◆ lastCompletedNodePath

List<GraphNode> lastCompletedNodePath

private

Used for drawing gizmos.

◆ lastCompletedVectorPath

List<Vector3> lastCompletedVectorPath

private

Used for drawing gizmos.

◆ lastPathID

uint lastPathID

protected

The path ID of the last path queried.

◆ modifiers

readonly List<IPathModifier> modifiers = new List<IPathModifier>()

private

Internal list of all modifiers.

◆ onPartialPathDelegate

readonly OnPathDelegate onPartialPathDelegate

private

Cached delegate to avoid allocating one every time a path is started.

◆ onPathDelegate

readonly OnPathDelegate onPathDelegate

private

Cached delegate to avoid allocating one every time a path is started.

◆ path

Path path

protected

The current path.

◆ pathCallback

OnPathDelegate pathCallback

Callback for when a path is completed.

Movement scripts should register to this delegate.
A temporary callback can also be set when calling StartPath, but that delegate will only be called for that path

◆ postProcessPath

OnPathDelegate postProcessPath

Called after a path has been calculated, right before modifiers are executed.

◆ preProcessPath

OnPathDelegate preProcessPath

Called before pathfinding is started.

◆ prevPath

Path prevPath

private

Previous path.

Used to draw gizmos

◆ startEndModifier

StartEndModifier startEndModifier = new StartEndModifier()

Path modifier which tweaks the start and end points of a path.

◆ tagPenalties

int [] tagPenalties = new int[32]

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 should always have a length of 32 otherwise the system will ignore it.

See also: Pathfinding.Path.tagPenalties

◆ tmpPathCallback

OnPathDelegate tmpPathCallback

private

Temporary callback only called for the current path.

This value is set by the StartPath functions

◆ traversableTags

int traversableTags = -1

The tags which the Seeker can traverse.

Note: This field is a bitmask.

See also: Bitmask Tutorial

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

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

Detailed Description

Public Types

Public Member Functions

Public Attributes

Protected Member Functions

Protected Attributes

Private Member Functions

Private Attributes

Member Enumeration Documentation

◆ ModifierPass

Constructor & Destructor Documentation

◆ Seeker()

Member Function Documentation

◆ Awake()

◆ CancelCurrentPathRequest()

◆ DeregisterModifier()

◆ GetCurrentPath()

◆ GetNewPath()

◆ IsDone()

◆ OnDestroy()

◆ OnDrawGizmos()

◆ OnMultiPathComplete()

◆ OnPartialPathComplete()

◆ OnPathComplete() [1/2]

◆ OnPathComplete() [2/2]

◆ OnUpgradeSerializedData()

◆ PostProcess()

◆ RegisterModifier()

◆ ReleaseClaimedPath()

◆ RunModifiers()

◆ StartMultiTargetPath() [1/3]

◆ StartMultiTargetPath() [2/3]

◆ StartMultiTargetPath() [3/3]

◆ StartPath() [1/5]

◆ StartPath() [2/5]

◆ StartPath() [3/5]

◆ StartPath() [4/5]

◆ StartPath() [5/5]

◆ StartPathInternal()

Member Data Documentation

◆ detailedGizmos

◆ drawGizmos

◆ graphMask

◆ graphMaskCompatibility

◆ lastCompletedNodePath

◆ lastCompletedVectorPath

◆ lastPathID

◆ modifiers

◆ onPartialPathDelegate

◆ onPathDelegate

◆ path

◆ pathCallback

◆ postProcessPath

◆ preProcessPath

◆ prevPath

◆ startEndModifier

◆ tagPenalties

◆ tmpPathCallback

◆ traversableTags