Base class for all nodes. More...

Detailed Description

Base class for all nodes.

Public Member Functions
abstract void	AddConnection (GraphNode node, uint cost)

abstract void	ClearConnections (bool alsoReverse)
	Remove all connections from this node. More...

virtual bool	ContainsConnection (GraphNode node)
	Checks if this node has a connection to the specified node. More...

virtual void	DeserializeNode (GraphSerializationContext ctx)
	Deserializes node data (for example when loading graphs from file). More...

virtual void	DeserializeReferences (GraphSerializationContext ctx)
	Used to deserialize references to other nodes e.g connections. More...

virtual void	FloodFill (Stack< GraphNode > stack, uint region)
	Internal method to run a flood fill in order to recalculate the Area property. More...

abstract void	GetConnections (System.Action< GraphNode > action)
	Calls the delegate with all connections from this node. More...

abstract void	GetConnections (System.Action< Connection > action)
	Calls the delegate with all connections and respective costs from this node. More...

virtual int	GetGizmoHashCode ()
	Hash code used for checking if the gizmos need to be updated. More...

virtual bool	GetPortal (GraphNode other, List< Vector3 > left, List< Vector3 > right, bool backwards)
	Add a portal from this node to the specified node. More...

abstract void	Open (Path path, PathNode pathNode, PathHandler handler)
	Open the node. More...

virtual void	OpenCooperative (CooperativeABPath path, PathNodeCooperative pathNode, CooperativePathHandler handler)
	Open the node cooperatively. More...

virtual Vector3	RandomPointOnSurface ()
	A random point on the surface of the node. More...

virtual void	RecalculateConnectionCosts ()
	Recalculates all connection costs from this node. More...

abstract void	RemoveConnection (GraphNode node)

virtual void	SerializeNode (GraphSerializationContext ctx)
	Serializes node data (for example when saving graphs to file). More...

virtual void	SerializeReferences (GraphSerializationContext ctx)
	Used to serialize references to other nodes e.g connections. More...

virtual float	SurfaceArea ()
	The surface area of the node in square world units. More...

virtual void	UpdateRecursiveG (Path path, PathNode pathNode, PathHandler handler)
	Internal method to update the G score. More...

Public Attributes
const uint	MaxAreaIndex = FlagsAreaMask >> FlagsAreaOffset

const uint	MaxGraphIndex = FlagsGraphMask >> FlagsGraphOffset
	Max number of graphs-1. More...

Int3	position
	Position of the node in world space. More...

Protected Member Functions
	GraphNode (AstarPath astar)
	Constructor for a graph node. More...

Protected Attributes
uint	flags
	Bitpacked field holding several pieces of data. More...

Package Functions
void	Destroy ()
	Destroys the node. More...

Properties
uint	Area `[get, set]`
	Connected component that contains the node. More...

bool	Destroyed `[get]`

uint	Flags `[get, set]`
	Holds various bitpacked variables. More...

NavGraph	Graph `[get]`
	Graph which this node belongs to. More...

uint	GraphIndex `[get, set]`
	Graph which contains this node. More...

int	NodeIndex `[get, private set]`
	Internal unique index. More...

uint	Penalty `[get, set]`
	Penalty cost for walking on this node. More...

uint	Tag `[get, set]`
	Node tag. More...

bool	TemporaryFlag1 `[get, set]`
	Temporary flag for internal purposes. More...

bool	TemporaryFlag2 `[get, set]`
	Temporary flag for internal purposes. More...

bool	Walkable `[get, set]`
	True if the node can be traversed. More...

Private Attributes
const int	DestroyedNodeIndex = NodeIndexMask - 1

const uint	FlagsAreaMask = (131072-1) << FlagsAreaOffset
	Mask of area bits. More...

const int	FlagsAreaOffset = 1
	Start of area bits. More...

const uint	FlagsGraphMask = (256u-1) << FlagsGraphOffset
	Mask of graph index bits. More...

const int	FlagsGraphOffset = 24
	Start of graph index bits. More...

const uint	FlagsTagMask = (32-1) << FlagsTagOffset
	Mask of tag bits. More...

const int	FlagsTagOffset = 19
	Start of tag bits. More...

const uint	FlagsWalkableMask = 1 << FlagsWalkableOffset
	Mask of the walkable bit. More...

const int	FlagsWalkableOffset = 0
	Position of the walkable bit. More...

int	nodeIndex
	Internal unique index. More...

const int	NodeIndexMask = 0xFFFFFFF

uint	penalty
	Penalty cost for walking on this node. More...

const int	TemporaryFlag1Mask = 0x10000000

const int	TemporaryFlag2Mask = 0x20000000

Constructor & Destructor Documentation

◆ GraphNode()

GraphNode ( AstarPath astar )

protected

Constructor for a graph node.

Member Function Documentation

◆ AddConnection()

abstract void AddConnection	(	GraphNode	node,
		uint	cost
	)

pure virtual

Implemented in MeshNode, GridNodeBase, and PointNode.

◆ ClearConnections()

abstract void ClearConnections ( bool alsoReverse )

pure virtual

Remove all connections from this node.

Parameters

alsoReverse if true, neighbours will be requested to remove connections to this node.

Implemented in LevelGridNode, MeshNode, GridNodeBase, GridNode, and PointNode.

◆ ContainsConnection()

virtual bool ContainsConnection ( GraphNode node )

virtual

Checks if this node has a connection to the specified node.

Reimplemented in MeshNode, GridNodeBase, and PointNode.

◆ DeserializeNode()

virtual void DeserializeNode ( GraphSerializationContext ctx )

virtual

Deserializes node data (for example when loading graphs from file).

See also: SerializeNode

Reimplemented in LevelGridNode, GridNode, TriangleMeshNode, and PointNode.

◆ DeserializeReferences()

virtual void DeserializeReferences ( GraphSerializationContext ctx )

virtual

Used to deserialize references to other nodes e.g connections.

Use the GraphSerializationContext.GetNodeIdentifier and GraphSerializationContext.GetNodeFromIdentifier methods for serialization and deserialization respectively.

Nodes must override this method and serialize their connections. Graph generators do not need to call this method, it will be called automatically on all nodes at the correct time by the serializer.

Reimplemented in MeshNode, GridNodeBase, and PointNode.

◆ Destroy()

void Destroy ( )

package

Destroys the node.

Cleans up any temporary pathfinding data used for this node. The graph is responsible for calling this method on nodes when they are destroyed, including when the whole graph is destoyed. Otherwise memory leaks might present themselves.

Once called the Destroyed property will return true and subsequent calls to this method will not do anything.

Note: Assumes the current active AstarPath instance is the same one that created this node.

Warning: Should only be called by graph classes on their own nodes

◆ FloodFill()

virtual void FloodFill	(	Stack< GraphNode >	stack,
		uint	region
	)

virtual

Internal method to run a flood fill in order to recalculate the Area property.

Reimplemented in LevelGridNode, MeshNode, and GridNode.

◆ GetConnections() [1/2]

abstract void GetConnections ( System.Action< GraphNode > action )

pure virtual

Calls the delegate with all connections from this node.

        node.GetConnections(connectedTo => {
            Debug.DrawLine((Vector3)node.position, (Vector3)connectedTo.position, Color.red);
        });

You can add all connected nodes to a list like this

var connections = new List<GraphNode>();

node.GetConnections(connections.Add);

Implemented in LevelGridNode, MeshNode, GridNodeBase, GridNode, and PointNode.

◆ GetConnections() [2/2]

abstract void GetConnections ( System.Action< Connection > action )

pure virtual

Calls the delegate with all connections and respective costs from this node.

Implemented in LevelGridNode, MeshNode, TriangleMeshNode, GridNodeBase, GridNode, and PointNode.

◆ GetGizmoHashCode()

virtual int GetGizmoHashCode ( )

virtual

Hash code used for checking if the gizmos need to be updated.

Will change when the gizmos for the node might change.

Reimplemented in LevelGridNode, MeshNode, PointNode, and GridNodeBase.

◆ GetPortal()

virtual bool GetPortal	(	GraphNode	other,
		List< Vector3 >	left,
		List< Vector3 >	right,
		bool	backwards
	)

virtual

Add a portal from this node to the specified node.

This function should add a portal to the left and right lists which is connecting the two nodes (this and other).

Parameters

other	The node which is on the other side of the portal (strictly speaking it does not actually have to be on the other side of the portal though).
left	List of portal points on the left side of the funnel
right	List of portal points on the right side of the funnel
backwards	If this is true, the call was made on a node with the other node as the node before this one in the path. In this case you may choose to do nothing since a similar call will be made to the other node with this node referenced as other (but then with backwards = true). You do not have to care about switching the left and right lists, that is done for you already.

Returns: True if the call was deemed successful. False if some unknown case was encountered and no portal could be added. If both calls to node1.GetPortal (node2,...) and node2.GetPortal (node1,...) return false, the funnel modifier will fall back to adding to the path the positions of the node.

The default implementation simply returns false.

This function may add more than one portal if necessary.

See also: http://digestingduck.blogspot.se/2010/03/simple-stupid-funnel-algorithm.html

Reimplemented in LevelGridNode, GridNode, and NodeLink3Node.

◆ Open()

abstract void Open	(	Path	path,
		PathNode	pathNode,
		PathHandler	handler
	)

pure virtual

Open the node.

Adds all neighbours of this node to the open list.

See also: https://en.wikipedia.org/wiki/A*_search_algorithm

Implemented in LevelGridNode, GridNode, TriangleMeshNode, GridNodeBase, and PointNode.

◆ OpenCooperative()

virtual void OpenCooperative	(	CooperativeABPath	path,
		PathNodeCooperative	pathNode,
		CooperativePathHandler	handler
	)

virtual

Open the node cooperatively.

Adds all neighbours of this node to the open list.

See also: https://en.wikipedia.org/wiki/A*_search_algorithm

◆ RandomPointOnSurface()

virtual Vector3 RandomPointOnSurface ( )

virtual

A random point on the surface of the node.

For point nodes and other nodes which do not have a surface, this will always return the position of the node.

Reimplemented in TriangleMeshNode, and GridNodeBase.

◆ RecalculateConnectionCosts()

virtual void RecalculateConnectionCosts ( )

virtual

Recalculates all connection costs from this node.

Depending on the node type, this may or may not be supported. Nothing will be done if the operation is not supported

Todo:: Use interface?

◆ RemoveConnection()

abstract void RemoveConnection ( GraphNode node )

pure virtual

Implemented in MeshNode, GridNodeBase, and PointNode.

◆ SerializeNode()

virtual void SerializeNode ( GraphSerializationContext ctx )

virtual

Serializes node data (for example when saving graphs to file).

See also: DeserializeNode

Reimplemented in LevelGridNode, GridNode, TriangleMeshNode, and PointNode.

◆ SerializeReferences()

virtual void SerializeReferences ( GraphSerializationContext ctx )

virtual

Used to serialize references to other nodes e.g connections.

Use the GraphSerializationContext.GetNodeIdentifier and GraphSerializationContext.GetNodeFromIdentifier methods for serialization and deserialization respectively.

Nodes must override this method and serialize their connections. Graph generators do not need to call this method, it will be called automatically on all nodes at the correct time by the serializer.

Reimplemented in MeshNode, GridNodeBase, and PointNode.

◆ SurfaceArea()

virtual float SurfaceArea ( )

virtual

The surface area of the node in square world units.

Reimplemented in TriangleMeshNode, and GridNodeBase.

◆ UpdateRecursiveG()

virtual void UpdateRecursiveG	(	Path	path,
		PathNode	pathNode,
		PathHandler	handler
	)

virtual

Internal method to update the G score.

Internal method to update the G score for this node and all children of it in the search graph

Reimplemented in LevelGridNode, MeshNode, GridNode, TriangleMeshNode, GridNodeBase, and PointNode.

Member Data Documentation

◆ DestroyedNodeIndex

const int DestroyedNodeIndex = NodeIndexMask - 1

private

◆ flags

uint flags

protected

Bitpacked field holding several pieces of data.

See also: Walkable; Area; GraphIndex; Tag

◆ FlagsAreaMask

const uint FlagsAreaMask = (131072-1) << FlagsAreaOffset

private

Mask of area bits.

See also: Area

◆ FlagsAreaOffset

const int FlagsAreaOffset = 1

private

Start of area bits.

See also: Area

◆ FlagsGraphMask

const uint FlagsGraphMask = (256u-1) << FlagsGraphOffset

private

Mask of graph index bits.

See also: GraphIndex

◆ FlagsGraphOffset

const int FlagsGraphOffset = 24

private

Start of graph index bits.

See also: GraphIndex

◆ FlagsTagMask

const uint FlagsTagMask = (32-1) << FlagsTagOffset

private

Mask of tag bits.

See also: Tag

◆ FlagsTagOffset

const int FlagsTagOffset = 19

private

Start of tag bits.

See also: Tag

◆ FlagsWalkableMask

const uint FlagsWalkableMask = 1 << FlagsWalkableOffset

private

Mask of the walkable bit.

See also: Walkable

◆ FlagsWalkableOffset

const int FlagsWalkableOffset = 0

private

Position of the walkable bit.

See also: Walkable

◆ MaxAreaIndex

const uint MaxAreaIndex = FlagsAreaMask >> FlagsAreaOffset

◆ MaxGraphIndex

const uint MaxGraphIndex = FlagsGraphMask >> FlagsGraphOffset

Max number of graphs-1.

◆ nodeIndex

int nodeIndex

private

Internal unique index.

Also stores some bitpacked values such as TemporaryFlag1 and TemporaryFlag2. This index is not necessarily correlated with e.g the position of the node in the graph.

Will be unique as long as the node is active. When the node is destroyed, the index may be reused by other nodes.

◆ NodeIndexMask

const int NodeIndexMask = 0xFFFFFFF

private

◆ penalty

uint penalty

private

Penalty cost for walking on this node.

This can be used to make it harder/slower to walk over certain nodes.

A penalty of 1000 (Int3.Precision) corresponds to the cost of walking one world unit.

◆ position

Int3 position

Position of the node in world space.

Note: The position is stored as an Int3, not a Vector3. You can convert an Int3 to a Vector3 using an explicit conversion.
var v3 = (Vector3)node.position;
and vice versa
node.position = (Int3)new Vector3(1,2,3);

◆ TemporaryFlag1Mask

const int TemporaryFlag1Mask = 0x10000000

private

◆ TemporaryFlag2Mask

const int TemporaryFlag2Mask = 0x20000000

private

Property Documentation

◆ Area

uint Area

getset

Connected component that contains the node.

This is visualized in the scene view as differently colored nodes (if the graph coloring mode is set to 'Areas'). Each area represents a set of nodes such that there is no valid path between nodes of different colors.

See also: https://en.wikipedia.org/wiki/Connected_component_(graph_theory); AstarPath.FloodFill

For performance reasons the graph is split up into several connected components using a flood fill. This is done so that if a path request is made between two nodes for which there is no possible path then it should be able to abort quickly instead of having to search the whole graph (which can be very expensive). It is also used to better be able to search for target nodes for paths (it will try to find the closest target node that can be reached instead of just the closest node to the target point).

When a graph update is done, this value usually needs to be updated. When using a GraphUpdateObject, that is done automatically, but for other kinds of updates, you may need to call some functions to update it (see docs on updating graphs).

See also: graph-updates; Tag

◆ Destroyed

bool Destroyed

get

◆ Flags

uint Flags

getset

Holds various bitpacked variables.

See also: Walkable; Area; GraphIndex; Tag

◆ Graph

NavGraph Graph

get

Graph which this node belongs to.

If you know the node belongs to a particular graph type, you can cast it to that type:

GraphNode node = ...;

GridGraph graph = node.Graph as GridGraph;

Will return null if the node has been destroyed.

◆ GraphIndex

uint GraphIndex

getset

Graph which contains this node.

See also: Pathfinding.AstarData.graphs

◆ NodeIndex

int NodeIndex

getprivate set

Internal unique index.

This index is not necessarily correlated with e.g the position of the node in the graph.

Will be unique as long as the node is active. When the node is destroyed, the index may be reused by other nodes.

◆ Penalty

uint Penalty

getset

Penalty cost for walking on this node.

This can be used to make it harder/slower to walk over certain areas. A cost of 1000 (Int3.Precision) corresponds to the cost of moving 1 world unit.

◆ Tag

uint Tag

getset

Node tag.

See also: Working with tags

◆ TemporaryFlag1

bool TemporaryFlag1

getsetpackage

Temporary flag for internal purposes.

May only be used in the Unity thread. Must be reset to false after every use.

◆ TemporaryFlag2

bool TemporaryFlag2

getsetpackage

Temporary flag for internal purposes.

May only be used in the Unity thread. Must be reset to false after every use.

◆ Walkable

bool Walkable

getset

True if the node can be traversed.

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

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

Detailed Description

Public Member Functions

Public Attributes

Protected Member Functions

Protected Attributes

Package Functions

Properties

Private Attributes

Constructor & Destructor Documentation

◆ GraphNode()

Member Function Documentation

◆ AddConnection()

◆ ClearConnections()

◆ ContainsConnection()

◆ DeserializeNode()

◆ DeserializeReferences()

◆ Destroy()

◆ FloodFill()

◆ GetConnections() [1/2]

◆ GetConnections() [2/2]

◆ GetGizmoHashCode()

◆ GetPortal()

◆ Open()

◆ OpenCooperative()

◆ RandomPointOnSurface()

◆ RecalculateConnectionCosts()

◆ RemoveConnection()

◆ SerializeNode()

◆ SerializeReferences()

◆ SurfaceArea()

◆ UpdateRecursiveG()

Member Data Documentation

◆ DestroyedNodeIndex

◆ flags

◆ FlagsAreaMask

◆ FlagsAreaOffset

◆ FlagsGraphMask

◆ FlagsGraphOffset

◆ FlagsTagMask

◆ FlagsTagOffset

◆ FlagsWalkableMask

◆ FlagsWalkableOffset

◆ MaxAreaIndex

◆ MaxGraphIndex

◆ nodeIndex

◆ NodeIndexMask

◆ penalty

◆ position

◆ TemporaryFlag1Mask

◆ TemporaryFlag2Mask

Property Documentation

◆ Area

◆ Destroyed

◆ Flags

◆ Graph

◆ GraphIndex

◆ NodeIndex

◆ Penalty

◆ Tag

◆ TemporaryFlag1

◆ TemporaryFlag2

◆ Walkable