Core component for the A* Pathfinding System. More...

Detailed Description

Core component for the A* Pathfinding System.

This class handles all of the pathfinding system, calculates all paths and stores the info.
This class is a singleton class, meaning there should only exist at most one active instance of it in the scene.
It might be a bit hard to use directly, usually interfacing with the pathfinding system is done through the Seeker class.

Examples:: MovePointNode.cs, MultiTargetFree.cs, and WaypointPath.cs.

Public Types
enum	AstarDistribution { WebsiteDownload, AssetStore }
	Information about where the package was downloaded. More...

Public Member Functions
void	AddWorkItem (System.Action callback)
	Add a work item to be processed when pathfinding is paused.

void	AddWorkItem (AstarWorkItem item)
	Add a work item to be processed when pathfinding is paused.

void	BlockUntilPathQueueBlocked ()
	Blocks until all pathfinding threads are paused and blocked.

void	EnsureValidFloodFill ()
	If a WorkItem needs to have a valid flood fill during execution, call this method to ensure there are no pending flood fills.

void	FloodFill (GraphNode seed)
	Floodfills starting from the specified node.

void	FloodFill (GraphNode seed, uint area)
	Floodfills starting from 'seed' using the specified area.

void	FloodFill ()
	Floodfills all graphs and updates areas for every node.

void	FlushGraphUpdates ()
	Forces graph updates to complete in a single frame.

void	FlushThreadSafeCallbacks ()
	Forces thread safe callbacks to run.

void	FlushWorkItems ()
	Forces work items to complete in a single frame.

void	FlushWorkItems (bool unblockOnComplete, bool block)
	Make sure work items are executed.

NNInfo	GetNearest (Vector3 position)
	Returns the nearest node to a position using the specified NNConstraint.

NNInfo	GetNearest (Vector3 position, NNConstraint constraint)
	Returns the nearest node to a position using the specified NNConstraint.

NNInfo	GetNearest (Vector3 position, NNConstraint constraint, GraphNode hint)
	Returns the nearest node to a position using the specified NNConstraint.

GraphNode	GetNearest (Ray ray)
	Returns the node closest to the ray (slow).

string[]	GetTagNames ()
	Returns tag names.

PathProcessor.GraphUpdateLock	PausePathfinding ()
	Blocks until all pathfinding threads are paused and blocked.

void	QueueGraphUpdates ()
	Will apply queued graph updates as soon as possible, regardless of batchGraphUpdates.

void	QueueWorkItemFloodFill ()
	Call during work items to queue a flood fill.

void	Scan (NavGraph graphToScan)
	Scans a particular graph.

void	Scan (NavGraph[] graphsToScan=null)
	Scans all specified graphs.

IEnumerable< Progress >	ScanAsync (NavGraph graphToScan)
	Scans a particular graph asynchronously.

IEnumerable< Progress >	ScanAsync (NavGraph[] graphsToScan=null)
	Scans all specified graphs asynchronously.

void	ScanLoop (OnScanStatus statusCallback)
	Scans all graphs.

void	UpdateGraphs (Bounds bounds, float delay)
	Update all graphs within bounds after delay seconds.

void	UpdateGraphs (GraphUpdateObject ob, float delay)
	Update all graphs using the GraphUpdateObject after delay seconds.

void	UpdateGraphs (Bounds bounds)
	Update all graphs within bounds.

void	UpdateGraphs (GraphUpdateObject ob)
	Update all graphs using the GraphUpdateObject.

Static Public Member Functions
static void	BlockUntilCalculated (Path p)
	Blocks until the path has been calculated.

static int	CalculateThreadCount (ThreadCount count)
	Calculates number of threads to use.

static string[]	FindTagNames ()
	Tries to find an AstarPath object and return tag names.

static void	RegisterSafeUpdate (System.Action callback, bool threadSafe)
	Will send a callback when it is safe to update nodes.

static void	RegisterSafeUpdate (System.Action callback)
	Will send a callback when it is safe to update nodes.

static void	StartPath (Path p, bool pushToFront=false)
	Puts the Path in queue for calculation.

static void	WaitForPath (Path p)
	Wait for the specified path to be calculated.

Public Attributes
AstarData	data
	Holds all graph data.

EuclideanEmbedding	euclideanEmbedding = new EuclideanEmbedding()
	Holds settings for heuristic optimization.

bool	showGraphs = false
	Shows or hides graph inspectors.

Static Public Attributes
static AstarPath	active
	Returns the active AstarPath object in the scene.

static readonly string	Branch = "master_Free"
	Which branch of the A* Pathfinding Project is this release.

static readonly AstarDistribution	Distribution = AstarDistribution.WebsiteDownload
	Used by the editor to guide the user to the correct place to download updates.

Protected Member Functions
override void	Awake ()
	Sets up all needed variables and scans the graphs.

Protected Member Functions inherited from VersionedMonoBehaviour
virtual int	OnUpgradeSerializedData (int version)
	Handle serialization backwards compatibility.

Package Functions
void	DestroyNode (GraphNode node)
	Internal method to destroy a given node.

int	GetNewNodeIndex ()
	Returns a new global node index.

ushort	GetNextPathID ()
	Returns the next free path ID.

void	InitializeNode (GraphNode node)
	Initializes temporary path data for a node.

void	Log (string s)
	Logs a string while taking into account logPathResults.

void	VerifyIntegrity ()
	Does simple error checking.

Properties
AstarData	astarData `[get]`
	Holds all graph data.

NavGraph[]	graphs `[get]`
	Shortcut to Pathfinding.AstarData.graphs.

System.Type[]	graphTypes `[get]`
	See Pathfinding.AstarData.

bool	IsAnyGraphUpdateInProgress `[get]`
	Returns if any graph updates are being calculated right now.

bool	IsAnyGraphUpdateQueued `[get]`
	Returns if any graph updates are waiting to be applied.

bool	IsAnyGraphUpdatesQueued `[get]`
	Returns if any graph updates are waiting to be applied.

bool	IsAnyWorkItemInProgress `[get]`
	Returns if any work items are in progress right now.

bool	isScanning `[get, set]`
	Set while any graphs are being scanned.

bool	IsUsingMultithreading `[get]`
	Returns whether or not multithreading is used.

int	NumParallelThreads `[get]`
	Number of parallel pathfinders.

static System.Version	Version `[get]`
	The version number for the A* Pathfinding Project.

Private Member Functions
	AstarPath ()

IEnumerator	DelayedGraphUpdate ()
	Waits a moment with updating graphs.

void	InitializeAstarData ()
	Initializes the AstarData class.

void	InitializePathProcessor ()
	Initializes the pathProcessor field.

void	InitializeProfiler ()
	Calls AstarProfiler.InitializeFastProfile.

void	LogPathResults (Path p)
	Prints path results to the log.

void	OnApplicationQuit ()
	Terminates pathfinding threads when the application quits.

void	OnDestroy ()
	Clears up variables and other stuff, destroys graphs.

void	OnDisable ()
	Cleans up meshes to avoid memory leaks.

void	OnDrawGizmos ()
	Calls OnDrawGizmos on graph generators.

void	OnGUI ()
	Draws the InGame debugging (if enabled), also shows the fps if 'L' is pressed down.

PathProcessor.GraphUpdateLock	PausePathfindingSoon ()
	Blocks the path queue so that e.g work items can be performed.

void	PerformBlockingActions (bool force=false)

void	RecalculateDebugLimits ()

IEnumerable< Progress >	ScanGraph (NavGraph graph)

void	Update ()
	Checks if any work items need to be executed then runs pathfinding for a while (if not using multithreading because then the calculation happens in other threads) and then returns any calculated paths to the scripts that requested them.

IEnumerator	UpdateGraphsInteral (GraphUpdateObject ob, float delay)
	Update all graphs using the GraphUpdateObject after delay seconds.

Private Attributes
Pathfinding.Util.RetainedGizmos	gizmos = new Pathfinding.Util.RetainedGizmos()

bool	graphUpdateRoutineRunning = false

readonly GraphUpdateProcessor	graphUpdates
	Processes graph updates.

bool	graphUpdatesWorkItemAdded = false
	Makes sure QueueGraphUpdates will not queue multiple graph update orders.

bool	isScanningBacking
	Backing field for isScanning.

float	lastGraphUpdate = -9999F
	Time the last graph update was done.

ushort	nextFreePathID = 1
	The next unused Path ID.

PathProcessor	pathProcessor
	Holds all paths waiting to be calculated and calculates them.

readonly PathReturnQueue	pathReturnQueue
	Holds all completed paths waiting to be returned to where they were requested.

PathProcessor.GraphUpdateLock	workItemLock
	Held if any work items are currently queued.

readonly WorkItemProcessor	workItems
	Processes work items.

Static Private Attributes
static int	waitForPathDepth = 0

Inspector - Debug
bool	showNavGraphs = true
	Toggle for showing the gizmo debugging for the graphs in the scene view (editor only).

bool	showUnwalkableNodes = true
	Toggle to show unwalkable nodes.

GraphDebugMode	debugMode
	The mode to use for drawing nodes in the sceneview.

float	debugFloor = 0
	Low value to use for certain debugMode modes.

float	debugRoof = 20000
	High value to use for certain debugMode modes.

bool	manualDebugFloorRoof = false
	If set, the debugFloor and debugRoof values will not be automatically recalculated.

bool	showSearchTree = false
	If enabled, nodes will draw a line to their 'parent'.

float	unwalkableNodeDebugSize = 0.3F
	Size of the red cubes shown in place of unwalkable nodes.

PathLog	logPathResults = PathLog.Normal
	The amount of debugging messages.

Inspector - Settings
float	maxNearestNodeDistanceSqr `[get]`
	Max Nearest Node Distance Squared.

bool	limitGraphUpdates `[get, set]`
	Batch graph updates.

float	maxGraphUpdateFreq `[get, set]`
	Limit for how often should graphs be updated.

float	maxNearestNodeDistance = 100
	Max Nearest Node Distance.

bool	scanOnStartup = true
	If true, all graphs will be scanned in Awake.

bool	fullGetNearestSearch = false
	Do a full GetNearest search for all graphs.

bool	prioritizeGraphs = false
	Prioritize graphs.

float	prioritizeGraphsLimit = 1F
	Distance limit for prioritizeGraphs.

AstarColor	colorSettings
	Reference to the color settings for this AstarPath object.

Heuristic	heuristic = Heuristic.Euclidean
	The heuristic to use.

float	heuristicScale = 1F
	The scale of the heuristic.

ThreadCount	threadCount = ThreadCount.None
	Number of pathfinding threads to use.

float	maxFrameTime = 1F
	Max number of milliseconds to spend each frame for pathfinding.

int	minAreaSize = 0
	Defines the minimum amount of nodes in an area.

bool	batchGraphUpdates = false
	Throttle graph updates and batch them to improve performance.

float	graphUpdateBatchingInterval = 0.2F
	Limit for how often should graphs be updated.

string[]	tagNames = null
	Stored tag names.

Debug Members
float	lastScanTime `[get, set]`
	The time it took for the last call to Scan() to complete.

PathHandler	debugPathData
	The path to debug using gizmos.

ushort	debugPathID
	The path ID to debug using gizmos.

string	inGameDebugPath
	Debug string from the last completed path.

Callbacks
static System.Action	OnAwakeSettings
	Called on Awake before anything else is done.

static OnGraphDelegate	OnGraphPreScan
	Called for each graph before they are scanned.

static OnGraphDelegate	OnGraphPostScan
	Called for each graph after they have been scanned.

static OnPathDelegate	OnPathPreSearch
	Called for each path before searching.

static OnPathDelegate	OnPathPostSearch
	Called for each path after searching.

static OnScanDelegate	OnPreScan
	Called before starting the scanning.

static OnScanDelegate	OnPostScan
	Called after scanning.

static OnScanDelegate	OnLatePostScan
	Called after scanning has completed fully.

static OnScanDelegate	OnGraphsUpdated
	Called when any graphs are updated.

static System.Action	On65KOverflow
	Called when pathID overflows 65536 and resets back to zero.

System.Action	OnGraphsWillBeUpdated

System.Action	OnGraphsWillBeUpdated2

Member Enumeration Documentation

enum AstarDistribution

Information about where the package was downloaded.

Enumerator:

WebsiteDownload
AssetStore

Constructor & Destructor Documentation

AstarPath ( )

private

Member Function Documentation

void AddWorkItem ( System.Action callback )

Add a work item to be processed when pathfinding is paused.

Convenience method that is equivalent to

AddWorkItem(new AstarWorkItem(callback));

Examples:: MovePointNode.cs.

void AddWorkItem ( AstarWorkItem item )

Add a work item to be processed when pathfinding is paused.

The work item will be executed when it is safe to update nodes. This is defined as between the path searches. When using more threads than one, calling this often might decrease pathfinding performance due to a lot of idling in the threads. Not performance as in it will use much CPU power, but performance as in the number of paths per second will probably go down (though your framerate might actually increase a tiny bit).

You should only call this function from the main unity thread (i.e normal game code).

var node = AstarPath.active.GetNearest (transform.position).node;
AstarPath.AddWorkItem (new AstarWorkItem((ctx) => {
    node.walkable = false;
    ctx.QueueFloodFill();
}));

var node = AstarPath.active.GetNearest (transform.position).node;
AstarPath.AddWorkItem (() => {
    node.position = (Int3)transform.position;
});

See Also: ProcessWorkItems; FlushWorkItems

override void Awake ( )

protectedvirtual

Sets up all needed variables and scans the graphs.

Calls Initialize, starts the ReturnPaths coroutine and scans all graphs. Also starts threads if using multithreading

See Also: OnAwakeSettings

Reimplemented from VersionedMonoBehaviour.

static void BlockUntilCalculated ( Path p )

static

Blocks until the path has been calculated.

Normally it takes a few frames for a path to be calculated and returned. This function will ensure that the path will be calculated when this function returns and that the callback for that path has been called.

If requesting a lot of paths in one go and waiting for the last one to complete, it will calculate most of the paths in the queue (only most if using multithreading, all if not using multithreading).

Use this function only if you really need to. There is a point to spreading path calculations out over several frames. It smoothes out the framerate and makes sure requesting a large number of paths at the same time does not cause lag.

Note: Graph updates and other callbacks might get called during the execution of this function.

When the pathfinder is shutting down. I.e in OnDestroy, this function will not do anything.

Parameters

p	The path to wait for. The path must be started, otherwise an exception will be thrown.

Exceptions

Exception if pathfinding is not initialized properly for this scene (most likely no AstarPath object exists) or if the path has not been started yet. Also throws an exception if critical errors occur such as when the pathfinding threads have crashed (which should not happen in normal cases). This prevents an infinite loop while waiting for the path.

See Also: Pathfinding.Path.WaitForPath; Pathfinding.Path.BlockUntilCalculated

void BlockUntilPathQueueBlocked ( )

Blocks until all pathfinding threads are paused and blocked.

Deprecated:: Use PausePathfinding instead. Make sure to call Release on the returned lock.

static int CalculateThreadCount ( ThreadCount count )

static

Calculates number of threads to use.

If count is not Automatic, simply returns count casted to an int.

Returns: An int specifying how many threads to use, 0 means a coroutine should be used for pathfinding instead of a separate thread.

If count is set to Automatic it will return a value based on the number of processors and memory for the current system. If memory is <= 512MB or logical cores are <= 1, it will return 0. If memory is <= 1024 it will clamp threads to max 2. Otherwise it will return the number of logical cores clamped to 6.

When running on WebGL this method always returns 0

IEnumerator DelayedGraphUpdate ( )

private

Waits a moment with updating graphs.

If batchGraphUpdates is set, we want to keep some space between them to let pathfinding threads running and then calculate all queued calls at once

void DestroyNode ( GraphNode node )

package

Internal method to destroy a given node.

This is to be called after the node has been disconnected from the graph so that it cannot be reached from any other nodes. It should only be called during graph updates, that is when the pathfinding threads are either not running or paused.

Warning: This method should not be called by user code. It is used internally by the system.

void EnsureValidFloodFill ( )

If a WorkItem needs to have a valid flood fill during execution, call this method to ensure there are no pending flood fills.

Deprecated:: This method has been moved. Use the method on the context object that can be sent with work item delegates instead

See Also: IWorkItemContext

static string [] FindTagNames ( )

static

Tries to find an AstarPath object and return tag names.

If an AstarPath object cannot be found, it returns an array of length 1 with an error message.

See Also: AstarPath.GetTagNames

void FloodFill ( GraphNode seed )

Floodfills starting from the specified node.

void FloodFill	(	GraphNode	seed,
		uint	area
	)

Floodfills starting from 'seed' using the specified area.

void FloodFill ( )

Floodfills all graphs and updates areas for every node.

The different colored areas that you see in the scene view when looking at graphs are called just 'areas', this method calculates which nodes are in what areas.

See Also: Pathfinding.Node.area

void FlushGraphUpdates ( )

Forces graph updates to complete in a single frame.

This will force the pathfinding threads to finish calculating the path they are currently calculating (if any) and then pause. When all threads have paused, graph updates will be performed.

Warning: Using this very often (many times per second) can reduce your fps due to a lot of threads waiting for one another. But you probably wont have to worry about that.

Note: This is almost identical to FlushWorkItems, but added for more descriptive name. This function will also override any time limit delays for graph updates. This is because graph updates are implemented using work items. So calling this function will also execute any other work items (if any are queued).

Will not do anything if there are no graph updates queued (not even execute other work items).

void FlushThreadSafeCallbacks ( )

Forces thread safe callbacks to run.

Deprecated:: Use FlushWorkItems instead

void FlushWorkItems ( )

Forces work items to complete in a single frame.

This will force all work items to run immidiately. This will force the pathfinding threads to finish calculating the path they are currently calculating (if any) and then pause. When all threads have paused, work items will be executed (which can be e.g graph updates).

Warning: Using this very often (many times per second) can reduce your fps due to a lot of threads waiting for one another. But you probably wont have to worry about that

Note: This is almost (note almost) identical to FlushGraphUpdates, but added for more descriptive name.

Will not do anything if there are no queued work items waiting to run.

void FlushWorkItems	(	bool	unblockOnComplete,
		bool	block
	)

Make sure work items are executed.

Parameters

unblockOnComplete	If true, pathfinding will be allowed to start running immediately after completing all work items.
block	If true, work items that usually take more than one frame to complete will be forced to complete during this call. If false, then after this call there might still be work left to do.

See Also: AddWorkItem

Deprecated:: Use FlushWorkItems() instead.

NNInfo GetNearest ( Vector3 position )

Returns the nearest node to a position using the specified NNConstraint.

Searches through all graphs for their nearest nodes to the specified position and picks the closest one.
Using the NNConstraint.None constraint.

See Also: Pathfinding.NNConstraint

NNInfo GetNearest	(	Vector3	position,
		NNConstraint	constraint
	)

Returns the nearest node to a position using the specified NNConstraint.

Searches through all graphs for their nearest nodes to the specified position and picks the closest one. The NNConstraint can be used to specify constraints on which nodes can be chosen such as only picking walkable nodes.

See Also: Pathfinding.NNConstraint

NNInfo GetNearest	(	Vector3	position,
		NNConstraint	constraint,
		GraphNode	hint
	)

Returns the nearest node to a position using the specified NNConstraint.

Searches through all graphs for their nearest nodes to the specified position and picks the closest one. The NNConstraint can be used to specify constraints on which nodes can be chosen such as only picking walkable nodes.

See Also: Pathfinding.NNConstraint

GraphNode GetNearest ( Ray ray )

Returns the node closest to the ray (slow).

Warning: This function is brute-force and very slow, use with caution

int GetNewNodeIndex ( )

package

Returns a new global node index.

Warning: This method should not be called directly. It is used by the GraphNode constructor.

ushort GetNextPathID ( )

package

Returns the next free path ID.

string [] GetTagNames ( )

Returns tag names.

Makes sure that the tag names array is not null and of length 32. If it is null or not of length 32, it creates a new array and fills it with 0,1,2,3,4 etc...

See Also: AstarPath.FindTagNames

void InitializeAstarData ( )

private

Initializes the AstarData class.

Searches for graph types, calls Awake on data and on all graphs

See Also: AstarData.FindGraphTypes

void InitializeNode ( GraphNode node )

package

Initializes temporary path data for a node.

Warning: This method should not be called directly. It is used by the GraphNode constructor.

void InitializePathProcessor ( )

private

Initializes the pathProcessor field.

void InitializeProfiler ( )

private

Calls AstarProfiler.InitializeFastProfile.

void Log ( string s )

package

Logs a string while taking into account logPathResults.

void LogPathResults ( Path p )

private

Prints path results to the log.

What it prints can be controled using logPathResults.

See Also: logPathResults; PathLog; Pathfinding.Path.DebugString

void OnApplicationQuit ( )

private

Terminates pathfinding threads when the application quits.

void OnDestroy ( )

private

Clears up variables and other stuff, destroys graphs.

Note that when destroying an AstarPath object, all static variables such as callbacks will be cleared.

void OnDisable ( )

private

Cleans up meshes to avoid memory leaks.

void OnDrawGizmos ( )

private

Calls OnDrawGizmos on graph generators.

void OnGUI ( )

private

Draws the InGame debugging (if enabled), also shows the fps if 'L' is pressed down.

See Also: logPathResults PathLog

PathProcessor.GraphUpdateLock PausePathfinding ( )

Blocks until all pathfinding threads are paused and blocked.

var graphLock = AstarPath.active.PausePathfinding();
// Here we can modify the graphs safely. For example by adding a new node to a point graph
var node = AstarPath.active.data.pointGraph.AddNode(new Vector3(3,1,4));
// Allow pathfinding to resume
graphLock.Release();

Returns: A lock object. You need to call Unlock on that object to allow pathfinding to resume.

Note: In most cases this should not be called from user code.

See Also: AddWorkItem; RegisterSafeUpdate

PathProcessor.GraphUpdateLock PausePathfindingSoon ( )

private

Blocks the path queue so that e.g work items can be performed.

void PerformBlockingActions ( bool force = false )

private

void QueueGraphUpdates ( )

Will apply queued graph updates as soon as possible, regardless of batchGraphUpdates.

Calling this multiple times will not create multiple callbacks. Makes sure DoUpdateGraphs is called as soon as possible.
This function is useful if you are limiting graph updates, but you want a specific graph update to be applied as soon as possible regardless of the time limit.

See Also: FlushGraphUpdates

void QueueWorkItemFloodFill ( )

Call during work items to queue a flood fill.

Deprecated:: This method has been moved. Use the method on the context object that can be sent with work item delegates instead

See Also: IWorkItemContext

void RecalculateDebugLimits ( )

private

static void RegisterSafeUpdate	(	System.Action	callback,
		bool	threadSafe
	)

static

Will send a callback when it is safe to update nodes.

This is defined as between the path searches. This callback will only be sent once and is nulled directly after the callback has been sent. When using more threads than one, calling this often might decrease pathfinding performance due to a lot of idling in the threads. Not performance as in it will use much CPU power, but performance as in the number of paths per second will probably go down (though your framerate might actually increase a tiny bit)

You should only call this function from the main unity thread (i.e normal game code).

Note: The threadSafe parameter has been deprecated

Deprecated:

static void RegisterSafeUpdate ( System.Action callback )

static

Will send a callback when it is safe to update nodes.

This is defined as between the path searches. This callback will only be sent once and is nulled directly after the callback has been sent. When using more threads than one, calling this often might decrease pathfinding performance due to a lot of idling in the threads. Not performance as in it will use much CPU power, but performance as in the number of paths per second will probably go down (though your framerate might actually increase a tiny bit)

You should only call this function from the main unity thread (i.e normal game code).

var node = AstarPath.active.GetNearest (transform.position).node;
AstarPath.RegisterSafeUpdate (() => {
    node.walkable = false;
});

var node = AstarPath.active.GetNearest (transform.position).node;
AstarPath.RegisterSafeUpdate (() => {
    node.position = (Int3)transform.position;
});

Version: Since version 4.0 this is equivalent to AddWorkItem(new AstarWorkItem(callback)). Previously the callbacks added using this method would not be ordered with respect to other work items, so they could be executed before other work items or after them.

Deprecated:: Use AddWorkItem(System.Action) instead. Note the slight change in behavior (mentioned above).

void Scan ( NavGraph graphToScan )

Scans a particular graph.

Calling this method will recalculate the specified graph. This method is pretty slow (depending on graph type and graph complexity of course), so it is advisable to use smaller graph updates whenever possible.

See Also: Graph Updates during Runtime; ScanAsync

void Scan ( NavGraph[] graphsToScan = null )

Scans all specified graphs.

Calling this method will recalculate all specified graphs or all graphs if the graphsToScan parameter is null. This method is pretty slow (depending on graph type and graph complexity of course), so it is advisable to use smaller graph updates whenever possible.

See Also: Graph Updates during Runtime; ScanAsync

Parameters

graphsToScan The graphs to scan. If this parameter is null then all graphs will be scanned

IEnumerable<Progress> ScanAsync ( NavGraph graphToScan )

Scans a particular graph asynchronously.

This is a IEnumerable, you can loop through it to get the progress

foreach (Progress progress in AstarPath.active.ScanAsync ()) {
  Debug.Log ("Scanning... " + progress.description + " - " + (progress.progress*100).ToString ("0") + "%");
}

You can scan graphs asyncronously by yielding when you loop through the progress. Note that this does not guarantee a good framerate, but it will allow you to at least show a progress bar during scanning.

IEnumerator Start () {
  foreach (Progress progress in AstarPath.active.ScanAsync ()) {
    Debug.Log ("Scanning... " + progress.description + " - " + (progress.progress*100).ToString ("0") + "%");
    yield return null;
  }
}

See Also: Scan

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

IEnumerable<Progress> ScanAsync ( NavGraph[] graphsToScan = null )

Scans all specified graphs asynchronously.

This is a IEnumerable, you can loop through it to get the progress

foreach (Progress progress in AstarPath.active.ScanAsync ()) {
  Debug.Log ("Scanning... " + progress.description + " - " + (progress.progress*100).ToString ("0") + "%");
}

You can scan graphs asyncronously by yielding when you loop through the progress. Note that this does not guarantee a good framerate, but it will allow you to at least show a progress bar during scanning.

IEnumerator Start () {
  foreach (Progress progress in AstarPath.active.ScanAsync ()) {
    Debug.Log ("Scanning... " + progress.description + " - " + (progress.progress*100).ToString ("0") + "%");
    yield return null;
  }
}

See Also: Scan

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

Parameters

graphsToScan The graphs to scan. If this parameter is null then all graphs will be scanned

IEnumerable<Progress> ScanGraph ( NavGraph graph )

private

void ScanLoop ( OnScanStatus statusCallback )

Scans all graphs.

Deprecated:: Use Scan or ScanAsync instead

See Also: Scan

static void StartPath	(	Path	p,
		bool	pushToFront = `false`
	)

static

Puts the Path in queue for calculation.

The callback specified when constructing the path will be called when the path has been calculated. Usually you should use the Seeker component instead of calling this function directly.

Parameters

p The path that should be put in queue for calculation

pushToFront If true, the path will be pushed to the front of the queue, bypassing all waiting paths and making it the next path to be calculated. This can be useful if you have a path which you want to prioritize over all others. Be careful to not overuse it though. If too many paths are put in the front of the queue often, this can lead to normal paths having to wait a very long time before being calculated.

Examples:: MultiTargetFree.cs, and WaypointPath.cs.

void Update ( )

private

Checks if any work items need to be executed then runs pathfinding for a while (if not using multithreading because then the calculation happens in other threads) and then returns any calculated paths to the scripts that requested them.

See Also: PerformBlockingActions; PathProcessor.TickNonMultithreaded; PathReturnQueue.ReturnPaths

void UpdateGraphs	(	Bounds	bounds,
		float	delay
	)

Update all graphs within bounds after delay seconds.

The graphs will be updated as soon as possible.

See Also: FlushGraphUpdates; batchGraphUpdates; Graph Updates during Runtime

void UpdateGraphs	(	GraphUpdateObject	ob,
		float	delay
	)

Update all graphs using the GraphUpdateObject after delay seconds.

This can be used to, e.g make all nodes in an area unwalkable, or set them to a higher penalty.

See Also: FlushGraphUpdates; batchGraphUpdates; Graph Updates during Runtime

void UpdateGraphs ( Bounds bounds )

Update all graphs within bounds.

The graphs will be updated as soon as possible.

This is equivalent to

UpdateGraphs (new GraphUpdateObject (bounds))

See Also: FlushGraphUpdates; batchGraphUpdates; Graph Updates during Runtime

void UpdateGraphs ( GraphUpdateObject ob )

Update all graphs using the GraphUpdateObject.

This can be used to, e.g make all nodes in an area unwalkable, or set them to a higher penalty. The graphs will be updated as soon as possible (with respect to batchGraphUpdates)

See Also: FlushGraphUpdates; batchGraphUpdates; Graph Updates during Runtime

IEnumerator UpdateGraphsInteral	(	GraphUpdateObject	ob,
		float	delay
	)

private

Update all graphs using the GraphUpdateObject after delay seconds.

void VerifyIntegrity ( )

package

Does simple error checking.

static void WaitForPath ( Path p )

static

Wait for the specified path to be calculated.

Normally it takes a few frames for a path to get calculated and returned.

Deprecated:: This method has been renamed to BlockUntilCalculated.

Member Data Documentation

AstarPath active

static

Returns the active AstarPath object in the scene.

Note: This is only set if the AstarPath object has been initialized (which happens in Awake).

Examples:: MovePointNode.cs.

bool batchGraphUpdates = false

Throttle graph updates and batch them to improve performance.

If toggled, graph updates will batched and executed less often (specified by graphUpdateBatchingInterval).

This can have a positive impact on pathfinding throughput since the pathfinding threads do not need to be stopped as often, and it reduces the overhead per graph update. All graph updates are still applied however, they are just batched together so that more of them are applied at the same time.

However do not use this if you want minimal latency between a graph update being requested and it being applied.

This only applies to graph updates requested using the UpdateGraphs method. Not those requested using RegisterSafeUpdate or AddWorkItem.

See Also: Graph Updates during Runtime

readonly string Branch = "master_Free"

static

Which branch of the A* Pathfinding Project is this release.

Used when checking for updates so that users of the development versions can get notifications of development updates.

AstarColor colorSettings

Reference to the color settings for this AstarPath object.

Color settings include for example which color the nodes should be in, in the sceneview.

AstarData data

Holds all graph data.

float debugFloor = 0

Low value to use for certain debugMode modes.

For example if debugMode is set to G, this value will determine when the node will be totally red.

Note: Only relevant in the editor

See Also: debugRoof

GraphDebugMode debugMode

The mode to use for drawing nodes in the sceneview.

Note: Only relevant in the editor

See Also: Pathfinding.GraphDebugMode

PathHandler debugPathData

The path to debug using gizmos.

This is the path handler used to calculate the last path. It is used in the editor to draw debug information using gizmos.

ushort debugPathID

The path ID to debug using gizmos.

float debugRoof = 20000

High value to use for certain debugMode modes.

For example if debugMode is set to G, this value will determine when the node will be totally green.

For the penalty debug mode, the nodes will be colored green when they have a penalty of zero and red when their penalty is greater or equal to this value and something between red and green for values in between.

Note: Only relevant in the editor

See Also: debugFloor

readonly AstarDistribution Distribution = AstarDistribution.WebsiteDownload

static

Used by the editor to guide the user to the correct place to download updates.

EuclideanEmbedding euclideanEmbedding = new EuclideanEmbedding()

Holds settings for heuristic optimization.

See Also: heuristic-opt

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

bool fullGetNearestSearch = false

Do a full GetNearest search for all graphs.

Additional searches will normally only be done on the graph which in the first fast search seemed to have the closest node. With this setting on, additional searches will be done on all graphs since the first check is not always completely accurate.
More technically: GetNearestForce on all graphs will be called if true, otherwise only on the one graph which's GetNearest search returned the best node.
Usually faster when disabled, but higher quality searches when enabled. When using a a navmesh or recast graph, for best quality, this setting should be combined with the Pathfinding.NavMeshGraph.accurateNearestNode setting set to true.

Note: For the PointGraph this setting doesn't matter much as it has only one search mode.

Pathfinding.Util.RetainedGizmos gizmos = new Pathfinding.Util.RetainedGizmos()

private

float graphUpdateBatchingInterval = 0.2F

Limit for how often should graphs be updated.

If batchGraphUpdates is true, this defines the minimum number of seconds between each graph update.

This can have a positive impact on pathfinding throughput since the pathfinding threads do not need to be stopped as often, and it reduces the overhead per graph update. All graph updates are still applied however, they are just batched together so that more of them are applied at the same time.

However do not use this if you want minimal latency between a graph update being requested and it being applied.

This only applies to graph updates requested using the UpdateGraphs method. Not those requested using RegisterSafeUpdate or AddWorkItem.

See Also: Graph Updates during Runtime

bool graphUpdateRoutineRunning = false

private

readonly GraphUpdateProcessor graphUpdates

private

Processes graph updates.

bool graphUpdatesWorkItemAdded = false

private

Makes sure QueueGraphUpdates will not queue multiple graph update orders.

Heuristic heuristic = Heuristic.Euclidean

The heuristic to use.

The heuristic, often referred to as 'H' is the estimated cost from a node to the target. Different heuristics affect how the path picks which one to follow from multiple possible with the same length

See Also: Pathfinding.Heuristic

float heuristicScale = 1F

The scale of the heuristic.

If a smaller value than 1 is used, the pathfinder will search more nodes (slower). If 0 is used, the pathfinding will be equal to dijkstra's algorithm. If a value larger than 1 is used the pathfinding will (usually) be faster because it expands fewer nodes, but the paths might not longer be optimal

string inGameDebugPath

private

Debug string from the last completed path.

Will be updated if logPathResults == PathLog.InGame

bool isScanningBacking

private

Backing field for isScanning.

Cannot use an auto-property because they cannot be marked with System.NonSerialized.

float lastGraphUpdate = -9999F

private

Time the last graph update was done.

Used to group together frequent graph updates to batches

PathLog logPathResults = PathLog.Normal

The amount of debugging messages.

Use less debugging to improve performance (a bit) or just to get rid of the Console spamming.
Use more debugging (heavy) if you want more information about what the pathfinding is doing.
InGame will display the latest path log using in game GUI.

bool manualDebugFloorRoof = false

If set, the debugFloor and debugRoof values will not be automatically recalculated.

Note: Only relevant in the editor

float maxFrameTime = 1F

Max number of milliseconds to spend each frame for pathfinding.

At least 500 nodes will be searched each frame (if there are that many to search). When using multithreading this value is quite irrelevant, but do not set it too low since that could add upp to some overhead, 10ms will work good for multithreading

float maxNearestNodeDistance = 100

Max Nearest Node Distance.

When searching for a nearest node, this is the limit (world units) for how far away it is allowed to be.

See Also: Pathfinding.NNConstraint.constrainDistance

int minAreaSize = 0

Defines the minimum amount of nodes in an area.

If an area has less than this amount of nodes, the area will be flood filled again with the area ID GraphNode.MaxAreaIndex-1, it shouldn't affect pathfinding in any significant way.
If you want to be able to separate areas from one another for some reason (for example to do a fast check to see if a path is at all possible) you should set this variable to 0.

Version: Since version 3.6, this variable should in most cases be set to 0 since the max number of area indices available has been greatly increased.

Deprecated:: This is handled automatically now

ushort nextFreePathID = 1

private

The next unused Path ID.

Incremented for every call to GetNextPathID

System.Action On65KOverflow

static

Called when pathID overflows 65536 and resets back to zero.

Note: This callback will be cleared every time it is called, so if you want to register to it repeatedly, register to it directly on receiving the callback as well.

System.Action OnAwakeSettings

static

Called on Awake before anything else is done.

This is called at the start of the Awake call, right after active has been set, but this is the only thing that has been done.
Use this when you want to set up default settings for an AstarPath component created during runtime since some settings can only be changed in Awake (such as multithreading related stuff)

//Create a new AstarPath object on Start and apply some default settings
public void Start () {
 AstarPath.OnAwakeSettings += ApplySettings;
 AstarPath astar = AddComponent<AstarPath>();
}
public void ApplySettings () {
 //Unregister from the delegate
 AstarPath.OnAwakeSettings -= ApplySettings;
 //For example threadCount should not be changed after the Awake call
 //so here's the only place to set it if you create the component during runtime
 AstarPath.active.threadCount = ThreadCount.One;
}

OnGraphDelegate OnGraphPostScan

static

Called for each graph after they have been scanned.

All other graphs might not have been scanned yet.

OnGraphDelegate OnGraphPreScan

static

Called for each graph before they are scanned.

OnScanDelegate OnGraphsUpdated

static

Called when any graphs are updated.

Register to for example recalculate the path whenever a graph changes.

System.Action OnGraphsWillBeUpdated

Deprecated:

System.Action OnGraphsWillBeUpdated2

Deprecated:

OnScanDelegate OnLatePostScan

static

Called after scanning has completed fully.

This is called as the last thing in the Scan function.

OnPathDelegate OnPathPostSearch

static

Called for each path after searching.

Be careful when using multithreading since this will be called from a different thread.

OnPathDelegate OnPathPreSearch

static

Called for each path before searching.

Be careful when using multithreading since this will be called from a different thread.

OnScanDelegate OnPostScan

static

Called after scanning.

This is called before applying links, flood-filling the graphs and other post processing.

OnScanDelegate OnPreScan

static

Called before starting the scanning.

PathProcessor pathProcessor

private

Holds all paths waiting to be calculated and calculates them.

readonly PathReturnQueue pathReturnQueue

private

Holds all completed paths waiting to be returned to where they were requested.

bool prioritizeGraphs = false

Prioritize graphs.

Graphs will be prioritized based on their order in the inspector. The first graph which has a node closer than prioritizeGraphsLimit will be chosen instead of searching all graphs.

float prioritizeGraphsLimit = 1F

Distance limit for prioritizeGraphs.

See Also: prioritizeGraphs

bool scanOnStartup = true

If true, all graphs will be scanned in Awake.

This does not include loading from the cache. If you disable this, you will have to call AstarPath.active.Scan () yourself to enable pathfinding. Alternatively you could load a saved graph from a file.

bool showGraphs = false

Shows or hides graph inspectors.

Used internally by the editor

bool showNavGraphs = true

Toggle for showing the gizmo debugging for the graphs in the scene view (editor only).

bool showSearchTree = false

If enabled, nodes will draw a line to their 'parent'.

This will show the search tree for the latest path.

Note: Only relevant in the editor

Todo:: Add a showOnlyLastPath flag to indicate whether to draw every node or only the ones visited by the latest path.

bool showUnwalkableNodes = true

Toggle to show unwalkable nodes.

Note: Only relevant in the editor

See Also: unwalkableNodeDebugSize

string [] tagNames = null

protected

Stored tag names.

See Also: AstarPath.FindTagNames; AstarPath.GetTagNames

ThreadCount threadCount = ThreadCount.None

Number of pathfinding threads to use.

Multithreading puts pathfinding in another thread, this is great for performance on 2+ core computers since the framerate will barely be affected by the pathfinding at all.

None indicates that the pathfinding is run in the Unity thread as a coroutine
Automatic will try to adjust the number of threads to the number of cores and memory on the computer. Less than 512mb of memory or a single core computer will make it revert to using no multithreading.

It is recommended that you use one of the "Auto" settings that are available. The reason is that even if your computer might be beefy and have 8 cores. Other computers might only be quad core or dual core in which case they will not benefit from more than 1 or 3 threads respectively (you usually want to leave one core for the unity thread). If you use more threads than the number of cores on the computer it is mostly just wasting memory, it will not run any faster. The extra memory usage is not trivially small. Each thread needs to keep a small amount of data for each node in all the graphs. It is not the full graph data but it is proportional to the number of nodes. The automatic settings will inspect the machine it is running on and use that to determine the number of threads so that no memory is wasted.

The exception is if you only have one (or maybe two characters) active at time. Then you should probably just go with one thread always since it is very unlikely that you will need the extra throughput given by more threads. Keep in mind that more threads primarily increases throughput by calculating different paths on different threads, it will not calculate individual paths any faster.

Note that if you are modifying the pathfinding core scripts or if you are directly modifying graph data without using any of the safe wrappers (like RegisterSafeUpdate) multithreading can cause strange errors and pathfinding stopping to work if you are not careful. For basic usage (not modding the pathfinding core) it should be safe.

Note: WebGL does not support threads at all (since javascript is single-threaded)

See Also: CalculateThreadCount

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

float unwalkableNodeDebugSize = 0.3F

Size of the red cubes shown in place of unwalkable nodes.

Note: Only relevant in the editor. Does not apply to grid graphs.

See Also: showUnwalkableNodes

int waitForPathDepth = 0

staticprivate

PathProcessor.GraphUpdateLock workItemLock

private

Held if any work items are currently queued.

readonly WorkItemProcessor workItems

private

Processes work items.

Property Documentation

AstarData astarData

get

Holds all graph data.

Deprecated:: The 'astarData' field has been renamed to 'data'

NavGraph [] graphs

get

Shortcut to Pathfinding.AstarData.graphs.

System.Type [] graphTypes

get

See Pathfinding.AstarData.

Deprecated:

bool IsAnyGraphUpdateInProgress

get

Returns if any graph updates are being calculated right now.

Note: This does *not* includes other types of work items such as navmesh cutting or anything added by RegisterSafeUpdate or AddWorkItem.

See Also: IsAnyWorkItemInProgress

bool IsAnyGraphUpdateQueued

get

Returns if any graph updates are waiting to be applied.

Note: This is false while the updates are being performed.; This does *not* includes other types of work items such as navmesh cutting or anything added by RegisterSafeUpdate or AddWorkItem.

bool IsAnyGraphUpdatesQueued

get

Returns if any graph updates are waiting to be applied.

Deprecated:: Use IsAnyGraphUpdateQueued instead

bool IsAnyWorkItemInProgress

get

Returns if any work items are in progress right now.

Note: This includes pretty much all types of graph updates. Such as normal graph updates, navmesh cutting and anything added by RegisterSafeUpdate or AddWorkItem.

bool isScanning

getset

Set while any graphs are being scanned.

It will be true up until the FloodFill is done.

Note: Not to be confused with graph updates.

Used to better support Graph Update Objects called for example in OnPostScan

See Also: IsAnyGraphUpdateQueued; IsAnyGraphUpdateInProgress

bool IsUsingMultithreading

get

Returns whether or not multithreading is used.

Exceptions

System.Exception Is thrown when it could not be decided if multithreading was used or not. This should not happen if pathfinding is set up correctly.

Note: This uses info about if threads are running right now, it does not use info from the settings on the A* object.

float lastScanTime

getset

The time it took for the last call to Scan() to complete.

Used to prevent automatically rescanning the graphs too often (editor only)

bool limitGraphUpdates

getset

Batch graph updates.

Deprecated:: This field has been renamed to batchGraphUpdates.

float maxGraphUpdateFreq

getset

Limit for how often should graphs be updated.

Deprecated:: This field has been renamed to graphUpdateBatchingInterval.

float maxNearestNodeDistanceSqr

get

Max Nearest Node Distance Squared.

See Also: maxNearestNodeDistance

int NumParallelThreads

get

Number of parallel pathfinders.

Returns the number of concurrent processes which can calculate paths at once. When using multithreading, this will be the number of threads, if not using multithreading it is always 1 (since only 1 coroutine is used).

See Also: threadInfos; IsUsingMultithreading

System.Version Version

staticget

The version number for the A* Pathfinding Project.

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

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

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