A* Pathfinding Project  3.8
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ConstantPath Class Reference

Finds all nodes within a specified distance from the start. More...

Detailed Description

Finds all nodes within a specified distance from the start.

This class will search outwards from the start point and find all nodes which it costs less than ConstantPath.maxGScore to reach, this is usually the same as the distance to them multiplied with 1000

The path can be called like:

//Here you create a new path and set how far it should search. Null is for the callback, but the seeker will handle that
ConstantPath cpath = ConstantPath.Construct (transform.position, 2000, null);
//Set the seeker to search for the path (where mySeeker is a variable referencing a Seeker component)
mySeeker.StartPath (cpath, myCallbackFunction);

Then when getting the callback, all nodes will be stored in the variable ConstantPath.allNodes (remember that you need to cast it from Path to ConstantPath first to get the variable).

This list will be sorted by G score (cost/distance to reach the node), however only the last duplicate of a node in the list is guaranteed to be sorted in this way.

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
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Public Member Functions

override void CalculateStep (long targetTick)
 Calculates the until it is complete or the time has progressed past targetTick.
 
override void Cleanup ()
 Always called after the path has been calculated.
 
override void Initialize ()
 Initializes the path.
 
override void OnEnterPool ()
 Called when the path enters the pool.
 
override void Prepare ()
 Called before the path is started.
 
override void Reset ()
 Reset the path to default values.
 
- Public Member Functions inherited from Path
void AdvanceState (PathState s)
 Threadsafe increment of the state.
 
uint CalculateHScore (GraphNode node)
 Estimated cost from the specified node to the target.
 
bool CanTraverse (GraphNode node)
 Returns if the node can be traversed.
 
void Claim (System.Object o)
 Claim this path (pooling).
 
virtual string DebugString (PathLog logMode)
 Returns a string with information about it.
 
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)
 
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.
 
void Release (System.Object o, bool silent=false)
 Releases a path claim (pooling).
 
void ReleaseSilent (System.Object o)
 Releases the path silently (pooling).
 
virtual void ReturnPath ()
 Calls callback to return the calculated path.
 
IEnumerator WaitForPath ()
 Waits until this path has been calculated and returned.
 

Static Public Member Functions

static ConstantPath Construct (Vector3 start, int maxGScore, OnPathDelegate callback=null)
 Constructs a ConstantPath starting from the specified point.
 

Public Attributes

List< GraphNodeallNodes
 Contains all nodes the path found.
 
PathEndingCondition endingCondition
 Controls when the path should terminate.
 
Vector3 originalStartPoint
 
GraphNode startNode
 
Vector3 startPoint
 
- Public Attributes inherited from Path
OnPathDelegate callback
 Callback to call when the path is complete.
 
float duration
 The duration of this path in ms.
 
int enabledTags = -1
 Which graph tags are traversable.
 
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.
 
NNConstraint nnConstraint = PathNNConstraint.Default
 Constraint for how to search for nodes.
 
List< GraphNodepath
 Holds the path as a Node array.
 
int searchedNodes
 Number of nodes this path has searched.
 
int searchIterations
 The number of frames/iterations this path has executed.
 
List< Vector3 > vectorPath
 Holds the (perhaps post processed) path as a Vector3 list.
 

Protected Member Functions

void Setup (Vector3 start, int maxGScore, OnPathDelegate callback)
 Sets up a ConstantPath starting from the specified point.
 
- Protected Member Functions inherited from Path
void DebugStringPrefix (PathLog logMode, System.Text.StringBuilder text)
 Writes text shared for all overrides of DebugString to the string builder.
 
void DebugStringSuffix (PathLog logMode, System.Text.StringBuilder text)
 Writes text shared for all overrides of DebugString to the string builder.
 
bool HasExceededTime (int searchedNodes, long targetTime)
 
virtual void Trace (PathNode from)
 Traces the calculated path from the end node to the start.
 

Properties

override bool FloodingPath [get]
 
- Properties inherited from Path
System.DateTime callTime [get, set]
 When the call was made to start the pathfinding for this path.
 
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]
 True for paths that want to search all nodes and not jump over nodes as optimizations.
 
PathHandler pathHandler [get, set]
 Data for the thread calculating this path.
 
ushort pathID [get, set]
 ID of this path.
 
bool recycled [get, set]
 True if the path is currently recycled (i.e in the path pool).
 
int[] tagPenalties [get, set]
 Penalties for each tag.
 

Additional Inherited Members

- Protected Attributes inherited from Path
PathNode currentR
 The node currently being processed.
 
bool hasBeenReset
 True if the Reset function has been called.
 
Int3 hTarget
 Target to use for H score calculations.
 
GraphNode hTargetNode
 Target to use for H score calculation.
 
int[] internalTagPenalties
 The tag penalties that are actually used.
 
int[] manualTagPenalties
 Tag penalties set by other scripts.
 
float maxFrameTime
 The max number of milliseconds per iteration (frame, in case of non-multithreading)
 
- Package Functions inherited from Path
void PrepareBase (PathHandler pathHandler)
 Prepares low level path variables for calculation.
 
- Package Attributes inherited from Path
Path next
 Internal linked list implementation.
 
bool pooled
 True if the path is currently pooled.
 

Member Function Documentation

override void CalculateStep ( long  targetTick)
virtual

Calculates the until it is complete or the time has progressed past targetTick.

Implements Path.

override 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 from Path.

static ConstantPath Construct ( Vector3  start,
int  maxGScore,
OnPathDelegate  callback = null 
)
static

Constructs a ConstantPath starting from the specified point.

Parameters
startFrom where the path will be started from (the closest node to that point will be used)
maxGScoreSearching will be stopped when a node has a G score greater than this
callbackWill be called when the path has completed, leave this to null if you use a Seeker to handle calls

Searching will be stopped when a node has a G score (cost to reach it) greater than maxGScore

override void Initialize ( )
virtual

Initializes the path.

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

Implements Path.

override 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 from Path.

override void Prepare ( )
virtual

Called before the path is started.

Called right before Initialize

Implements Path.

override void Reset ( )
virtual

Reset the path to default values.

Clears the allNodes list.

Note
This does not reset the endingCondition.

Also sets heuristic to Heuristic.None as it is the default value for this path type

Reimplemented from Path.

void Setup ( Vector3  start,
int  maxGScore,
OnPathDelegate  callback 
)
protected

Sets up a ConstantPath starting from the specified point.

Member Data Documentation

List<GraphNode> allNodes

Contains all nodes the path found.

Note
Due to the nature of the search, there might be duplicates of some nodes in the array. This list will be sorted by G score (cost/distance to reach the node), however only the last duplicate of a node in the list is guaranteed to be sorted in this way.
PathEndingCondition endingCondition

Controls when the path should terminate.

This is set up automatically in the constructor to an instance of the Pathfinding.EndingConditionDistance class with a maxGScore is specified in the constructor. If you want to use another ending condition.

See Also
Pathfinding.PathEndingCondition for examples
Vector3 originalStartPoint
GraphNode startNode
Vector3 startPoint

Property Documentation

override bool FloodingPath
get

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