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ABPath Class Reference

Basic path, finds the shortest path from A to B. More...

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Public Member Functions

 ABPath (Vector3 start, Vector3 end, OnPathDelegate callbackDelegate)
 Create a new path with a start and end point.
 
override void CalculateStep (long targetTick)
 Calculates the path until completed or until the time has passed targetTick.
 
override string DebugString (PathLog logMode)
 Returns a debug string for this path.
 
Vector3 GetMovementVector (Vector3 point)
 Returns in which direction to move from a point on the path.
 
override void Initialize ()
 Initializes the path.
 
override void Prepare ()
 Prepares the path.
 
override void Reset ()
 Reset all values to their default values.
 
void ResetCosts (Path p)
 Resets End Node Costs.
 
- Public Member Functions inherited from Path
void AdvanceState (PathState s)
 Threadsafe increment of the state.
 
bool CanTraverse (Node node)
 Returns if the node can be traversed.
 
void Claim (System.Object o)
 Claim this path.
 
void Error ()
 Aborts the path because of an error.
 
void ForceLogError (string msg)
 Logs an error and calls Error() to true.
 
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.
 
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.
 
void PrepareBase (NodeRunData runData)
 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 ReturnPath ()
 Calls callback to return the calculated path.
 
virtual void Trace (NodeRun from)
 Traces the calculated path from the end node to the start.
 

Public Attributes

bool calculatePartial = false
 Calculate partial path if the target node cannot be reached.
 
Node endHint
 Hints can be set to enable faster Get Nearest Node queries.
 
Node endNode
 End node of the path.
 
Vector3 endPoint
 Exact end point of the path.
 
Int3 hTarget
 Target to use for H score calculations.
 
Vector3 originalEndPoint
 End Point exactly as in the path request.
 
Vector3 originalStartPoint
 Start Point exactly as in the path request.
 
bool recalcStartEndCosts = true
 Defines if start and end nodes will have their connection costs recalculated for this path.
 
Node startHint
 Hints can be set to enable faster Get Nearest Node queries.
 
Int3 startIntPoint
 Start point in integer coordinates.
 
Node startNode
 Start node of the path.
 
Vector3 startPoint
 Exact start point of the path.
 
- Public Attributes inherited from Path
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.
 
Path next
 The next path to be searched.
 
NNConstraint nnConstraint = PathNNConstraint.Default
 Constraint for how to search for nodes.
 
List< Nodepath
 Holds the path as a Node array.
 
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).
 
NodeRunData runData
 
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

override void Recycle ()
 Recycle the path.
 
void UpdateStartEnd (Vector3 start, Vector3 end)
 Sets the start and end points.
 
- Protected Member Functions inherited from Path
bool HasExceededTime (int searchedNodes, long targetTime)
 

Protected Attributes

int[] endNodeCosts
 Saved original costs for the end node.
 
bool hasEndPoint = true
 Determines if a search for an end node should be done.
 
NodeRun partialBestTarget = null
 Current best target for the partial path.
 
- Protected Attributes inherited from Path
int[] _tagPenalties = new int[0]
 Penalties for each tag.
 
NodeRun currentR
 The node currently being processed.
 
bool hasBeenReset = false
 True if the Reset function has been called.
 
float maxFrameTime
 The max number of milliseconds per iteration (frame, in case of non-multithreading)
 

Constructors

 ABPath ()
 Default constructor.
 
static ABPath Construct (Vector3 start, Vector3 end, OnPathDelegate callback=null)
 Construct a path with a start and end point.
 
void Setup (Vector3 start, Vector3 end, OnPathDelegate callbackDelegate)
 

Additional Inherited Members

- Properties inherited from Path
PathCompleteState CompleteState [get, set]
 
bool error [get]
 If the path failed, this is true.
 
string errorLog [get]
 Log messages with info about eventual errors.
 
int[] tagPenalties [get, set]
 Penalties for each tag.
 

Detailed Description

Basic path, finds the shortest path from A to B.

This is the most basic path object it will try to find the shortest path from A to B.
Many other path types inherit from this type.

See Also
Seeker::StartPath

Constructor & Destructor Documentation

ABPath ( Vector3  start,
Vector3  end,
OnPathDelegate  callbackDelegate 
)

Create a new path with a start and end point.

The delegate will be called when the path has been calculated. Do not confuse it with the Seeker callback as they are sent at different times. If you are using a Seeker to start the path you can set callbackDelegate to null

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ABPath ( )

Default constructor.

Do not use this. Instead use Pathfinding.PathPool<Pathfinding.Path>.GetPath()
If you want to use the constructor, use this:

ABPath p = new ABPath();
p.Reset();

And then use a Setup() method.

Member Function Documentation

override void CalculateStep ( long  targetTick)
virtual

Calculates the path until completed or until the time has passed targetTick.

Usually a check is only done every 500 nodes if the time has passed targetTick. Time/Ticks are got from System.DateTime.UtcNow.Ticks.

Basic outline of what the function does for the standard path (Pathfinding.ABPath).

while the end has not been found and no error has ocurred
check if we have reached the end
if so, exit and return the path
open the current node, i.e loop through its neighbours, mark them as visited and put them on a heap
check if there are still nodes left to process (or have we searched the whole graph)
if there are none, flag error and exit
pop the next node of the heap and set it as current
check if the function has exceeded the time limit
if so, return and wait for the function to get called again

Implements Path.

Reimplemented in MultiTargetPath, RandomPath, FloodPathTracer, and XPath.

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static ABPath Construct ( Vector3  start,
Vector3  end,
OnPathDelegate  callback = null 
)
static

Construct a path with a start and end point.

The delegate will be called when the path has been calculated. Do not confuse it with the Seeker callback as they are sent at different times. If you are using a Seeker to start the path you can set callback to null.

Returns
The constructed path object

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Vector3 GetMovementVector ( Vector3  point)

Returns in which direction to move from a point on the path.

A simple and quite slow (well, compared to more optimized algorithms) algorithm first finds the closest path segment (from vectorPath) and then returns the direction to the next point from there. The direction is not normalized.

Returns
Direction to move from a point, returns Vector3::zero if vectorPath is null or has a length of 0

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override void Initialize ( )
virtual

Initializes the path.

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

Implements Path.

Reimplemented in MultiTargetPath, RandomPath, FloodPathTracer, and XPath.

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override void Prepare ( )
virtual

Prepares the path.

Searches for start and end nodes and does some simple checking if a path is at all possible

Implements Path.

Reimplemented in MultiTargetPath, and RandomPath.

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override void Recycle ( )
protectedvirtual

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);
}
Note
Do not call this function directly, instead use the Claim and Release functions.
See Also
Pathfinding.PathPool
Reset
Claim
Release

Implements Path.

Reimplemented in MultiTargetPath, RandomPath, and XPath.

override void Reset ( )
virtual

Reset all values to their default values.

All inheriting path types must implement this function, resetting ALL their variables to enable recycling of paths. Call this base function in inheriting types with base.Reset ();

Reimplemented from Path.

Reimplemented in FloodPathTracer, RandomPath, and XPath.

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void ResetCosts ( Path  p)

Resets End Node Costs.

Costs are updated on the end node at the start of the search to better reflect the end point passed to the path, the previous ones are saved in endNodeCosts and are reset in this function which is called after the path search is complete

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void UpdateStartEnd ( Vector3  start,
Vector3  end 
)
protected

Sets the start and end points.

Sets originalStartPoint, originalEndPoint, startPoint, endPoint, startIntPoint and hTarget (to end )

Member Data Documentation

bool calculatePartial = false

Calculate partial path if the target node cannot be reached.

If the target node cannot be reached, the node which was closest (given by heuristic) will be chosen as target node and a partial path will be returned. This only works if a heuristic is used (which is the default). If a partial path is found, CompleteState is set to Partial.

Note
It is not required by other path types to respect this setting
Node endHint

Hints can be set to enable faster Get Nearest Node queries.

Only applies to some graph types

int [] endNodeCosts
protected

Saved original costs for the end node.

See Also
ResetCosts
bool hasEndPoint = true
protected

Determines if a search for an end node should be done.

Set by different path types.

Since
Added in 3.0.8.3
Int3 hTarget

Target to use for H score calculations.

See Also
Pathfinding::Node::h
NodeRun partialBestTarget = null
protected

Current best target for the partial path.

This is the node with the lowest H score

bool recalcStartEndCosts = true

Defines if start and end nodes will have their connection costs recalculated for this path.

These connection costs will be more accurate and based on the exact start point and target point, however it should not be used when connection costs are not the default ones (all build in graph generators currently generate default connection costs).

See Also
Int3.costMagnitude
Since
Added in 3.0.8.3
Bug:
Does not do anything in 3.2 and up due to incompabilities with multithreading. Will be enabled again in later versions.
Node startHint

Hints can be set to enable faster Get Nearest Node queries.

Only applies to some graph types


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