Grid Graph, supports layered worlds. More...

Detailed Description

Grid Graph, supports layered worlds.

The GridGraph is great in many ways, reliable, easily configured and updatable during runtime. But it lacks support for worlds which have multiple layers, such as a building with multiple floors.
That's where this graph type comes in. It supports basically the same stuff as the grid graph, but also multiple layers. It uses a more memory, and is probably a bit slower.

Note: Does not support 8 connections per node, only 4.

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

Public Member Functions
void	AddLayers (int count)
	Increases the capacity of the nodes array to hold more layers.

void	CalculateConnections (GraphNode[] nodes, GraphNode node, int x, int z, int layerIndex)
	Calculates the layered grid graph connections for a single node.

override int	CountNodes ()
	Count nodes in the graph.

override void	DeserializeExtraInfo (GraphSerializationContext ctx)
	Deserializes graph type specific node data.

override void	ErodeWalkableArea (int xmin, int zmin, int xmax, int zmax)
	Erodes the walkable area.

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

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

override void	GetNodes (GraphNodeDelegateCancelable del)
	Calls a delegate with all nodes in the graph.

override void	OnDestroy ()
	This function will be called when this graph is destroyed.

override void	OnDrawGizmos (bool drawNodes)
	Draw gizmos for the graph.

override void	PostDeserialization ()
	Called after all deserialization has been done for all graphs.

bool	RecalculateCell (int x, int z, bool preserveExistingNodes)
	Recalculates single cell.

override void	ScanInternal (OnScanStatus statusCallback)
	Scans the graph, called from AstarPath.ScanLoop.

override void	SerializeExtraInfo (GraphSerializationContext ctx)
	Serializes graph type specific node data.

new void	UpdateArea (GraphUpdateObject o)

virtual void	UpdatePenalty (LevelGridNode node)
	Updates penalty for the node.

Public Member Functions inherited from GridGraph
	GridGraph ()

virtual void	CalculateConnections (GridNode[] nodes, int x, int z, GridNode node)
	Calculates the grid connections for a single node.

virtual void	CalculateConnections (int x, int z, GridNode node)
	Calculates the grid connections for a single node.

GraphUpdateThreading	CanUpdateAsync (GraphUpdateObject o)

bool	CheckConnection (GridNode node, int dir)
	Returns if node is connected to it's neighbour in the specified direction.

override void	DeserializeSettingsCompatibility (GraphSerializationContext ctx)
	An old format for serializing settings.

virtual void	ErodeWalkableArea ()
	Erodes the walkable area.

void	GenerateMatrix ()
	Generates the matrix used for translating nodes from grid coordinates to world coordintes.

uint	GetConnectionCost (int dir)

GridNode	GetNodeConnection (GridNode node, int dir)

List< GraphNode >	GetNodesInArea (Bounds b)
	All nodes inside the bounding box.

List< GraphNode >	GetNodesInArea (GraphUpdateShape shape)
	All nodes inside the shape.

Int3	GraphPointToWorld (int x, int z, float height)
	Transform a point in graph space to world space.

bool	HasNodeConnection (GridNode node, int dir)

bool	HasNodeConnection (int index, int x, int z, int dir)

virtual bool	IsValidConnection (GridNode n1, GridNode n2)
	Returns true if a connection between the adjacent nodes n1 and n2 is valid.

bool	Linecast (Vector3 _a, Vector3 _b)
	Returns if there is an obstacle between origin and end on the graph.

bool	Linecast (Vector3 _a, Vector3 _b, GraphNode hint)
	Returns if there is an obstacle between origin and end on the graph.

bool	Linecast (Vector3 _a, Vector3 _b, GraphNode hint, out GraphHitInfo hit)
	Returns if there is an obstacle between origin and end on the graph.

bool	Linecast (Vector3 _a, Vector3 _b, GraphNode hint, out GraphHitInfo hit, List< GraphNode > trace)
	Returns if there is an obstacle between _a and _b on the graph.

void	OnPostScan (AstarPath script)
	Auto links grid graphs together.

void	RelocateNodes (Vector3 center, Quaternion rotation, float nodeSize, float aspectRatio=1, float isometricAngle=0)
	Relocate the grid graph using new settings.

void	SetNodeConnection (GridNode node, int dir, bool value)

void	SetNodeConnection (int index, int x, int z, int dir, bool value)
	Set if connection in the specified direction should be enabled.

virtual void	SetUpOffsetsAndCosts ()
	Sets up neighbourOffsets with the current settings.

bool	SnappedLinecast (Vector3 a, Vector3 b, GraphNode hint, out GraphHitInfo hit)
	Returns if there is an obstacle between and on the graph.

void	UpdateArea (GraphUpdateObject o)
	Internal function to update an area of the graph.

void	UpdateAreaInit (GraphUpdateObject o)

virtual void	UpdateNodePositionCollision (GridNode node, int x, int z, bool resetPenalty=true)
	Updates position, walkability and penalty for the node.

void	UpdateSizeFromWidthDepth ()
	Updates size from width, depth and nodeSize values.

Public Member Functions inherited from NavGraph
virtual void	Awake ()
	This will be called on the same time as Awake on the gameObject which the AstarPath script is attached to.

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

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

virtual Color	NodeColor (GraphNode node, PathHandler data)

virtual void	RelocateNodes (Matrix4x4 oldMatrix, Matrix4x4 newMatrix)
	Relocates the nodes in this graph.

void	Scan ()

void	ScanGraph ()

void	ScanInternal ()
	Internal method for scanning graphs.

void	SetMatrix (Matrix4x4 m)
	Use to set both matrix and inverseMatrix at the same time.

Public Member Functions inherited from IUpdatableGraph
GraphUpdateThreading	CanUpdateAsync (GraphUpdateObject o)

void	UpdateArea (GraphUpdateObject o)
	Updates an area using the specified GraphUpdateObject.

void	UpdateAreaInit (GraphUpdateObject o)

Public Member Functions inherited from IRaycastableGraph
bool	Linecast (Vector3 start, Vector3 end)

bool	Linecast (Vector3 start, Vector3 end, GraphNode hint)

bool	Linecast (Vector3 start, Vector3 end, GraphNode hint, out GraphHitInfo hit)

bool	Linecast (Vector3 start, Vector3 end, GraphNode hint, out GraphHitInfo hit, List< GraphNode > trace)

Static Public Member Functions
static bool	CheckConnection (LevelGridNode node, int dir)
	Returns if node is connected to it's neighbour in the specified direction.

Static Public Member Functions inherited from GridGraph
static void	CalculateConnections (GridNode node)
	Calculates the grid connections for a single node.

Static Public Member Functions inherited from NavGraph
static bool	InSearchTree (GraphNode node, Path path)
	Returns if the node is in the search tree of the path.

Public Attributes
float	characterHeight = 0.4F
	Nodes with a short distance to the node above it will be set unwalkable.

int	layerCount
	Number of layers.

float	mergeSpanRange = 0.5F
	If two layered nodes are too close, they will be merged.

new LevelGridNode[]	nodes

Public Attributes inherited from GridGraph
const int	getNearestForceOverlap = 2
	In GetNearestForce, determines how far to search after a valid node has been found.

readonly uint[]	neighbourCosts = new uint[8]
	Costs to neighbour nodes.

readonly int[]	neighbourOffsets = new int[8]
	Index offset to get neighbour nodes.

readonly int[]	neighbourXOffsets = new int[8]
	Offsets in the X direction for neighbour nodes.

readonly int[]	neighbourZOffsets = new int[8]
	Offsets in the Z direction for neighbour nodes.

GridNode[]	nodes
	All nodes in this graph.

int	width
	Width of the grid in nodes.

int	depth
	Depth (height) of the grid in nodes.

float	aspectRatio = 1F
	Scaling of the graph along the X axis.

float	isometricAngle
	Angle to use for the isometric projection.

bool	uniformEdgeCosts
	If true, all edge costs will be set to the same value.

Vector3	rotation
	Rotation of the grid in degrees.

Vector3	center
	Center point of the grid.

Vector2	unclampedSize
	Size of the grid.

float	nodeSize = 1
	Size of one node in world units.

GraphCollision	collision
	Settings on how to check for walkability and height.

float	maxClimb = 0.4F
	The max position difference between two nodes to enable a connection.

int	maxClimbAxis = 1
	The axis to use for maxClimb.

float	maxSlope = 90
	The max slope in degrees for a node to be walkable.

int	erodeIterations
	Erosion of the graph.

bool	erosionUseTags
	Use tags instead of walkability for erosion.

int	erosionFirstTag = 1
	Tag to start from when using tags for erosion.

bool	autoLinkGrids
	Auto link the graph's edge nodes together with other GridGraphs in the scene on Scan.

float	autoLinkDistLimit = 10F
	Distance limit for grid graphs to be auto linked.

NumNeighbours	neighbours = NumNeighbours.Eight
	Number of neighbours for each node.

bool	cutCorners = true
	If disabled, will not cut corners on obstacles.

float	penaltyPositionOffset
	Offset for the position when calculating penalty.

bool	penaltyPosition
	Use position (y-coordinate) to calculate penalty.

float	penaltyPositionFactor = 1F
	Scale factor for penalty when calculating from position.

bool	penaltyAngle

float	penaltyAngleFactor = 100F
	How much penalty is applied depending on the slope of the terrain.

float	penaltyAnglePower = 1
	How much extra to penalize very steep angles.

bool	useJumpPointSearch

TextureData	textureData = new TextureData()
	Holds settings for using a texture as source for a grid graph.

Public Attributes inherited from NavGraph
AstarPath	active
	Reference to the AstarPath object in the scene.

bool	drawGizmos = true

uint	graphIndex
	Index of the graph, used for identification purposes.

Guid	guid
	Used as an ID of the graph, considered to be unique.

bool	infoScreenOpen
	Used in the editor to check if the info screen is open.

uint	initialPenalty
	Default penalty to apply to all nodes.

Matrix4x4	inverseMatrix = Matrix4x4.identity
	Inverse of matrix.

Matrix4x4	matrix = Matrix4x4.identity
	A matrix for translating/rotating/scaling the graph.

string	name
	Name of the graph.

bool	open
	Is the graph open in the editor.

Protected Member Functions
override GridNodeBase	GetNeighbourAlongDirection (GridNodeBase node, int direction)
	Utility method used by Linecast.

Protected Member Functions inherited from GridGraph
bool	ClipLineSegmentToBounds (Vector3 a, Vector3 b, out Vector3 outA, out Vector3 outB)
	Clips a line segment in graph space to the graph bounds.

Package Attributes
int	lastScannedDepth

int	lastScannedWidth

Properties
override bool	uniformWidthDepthGrid `[get]`

Properties inherited from GridGraph
Matrix4x4	boundsMatrix `[get, set]`

int	Depth `[get, set]`

Vector2	size `[get, set]`
	Size of the grid.

virtual bool	uniformWidthDepthGrid `[get]`
	This is placed here so generators inheriting from this one can override it and set it to false.

int	Width `[get, set]`

bool	useRaycastNormal `[get]`
	Use heigh raycasting normal for max slope calculation.

Private Member Functions
LevelGridNode	GetNearestNode (Vector3 position, int x, int z, NNConstraint constraint)

void	RemoveGridGraphFromStatic ()

Additional Inherited Members
Static Protected Member Functions inherited from GridGraph
static float	CrossMagnitude (Vector2 a, Vector2 b)
	Magnitude of the cross product a x b.

static void	GetBoundsMinMax (Bounds b, Matrix4x4 matrix, out Vector3 min, out Vector3 max)
	Calculates minimum and maximum points for bounds b when multiplied with the matrix.

Package Functions inherited from NavGraph
virtual void	UnloadGizmoMeshes ()
	Called when temporary meshes used in OnDrawGizmos need to be unloaded to prevent memory leaks.

Static Package Attributes inherited from GridGraph
static readonly int[]	hexagonNeighbourIndices = { 0, 1, 2, 3, 5, 7 }
	Which neighbours are going to be used when neighbours=6.

Member Function Documentation

void AddLayers ( int count )

Increases the capacity of the nodes array to hold more layers.

After this function has been called and new nodes have been set up, the AstarPath.DataUpdate function must be called.

void CalculateConnections	(	GraphNode[]	nodes,
		GraphNode	node,
		int	x,
		int	z,
		int	layerIndex
	)

Calculates the layered grid graph connections for a single node.

static bool CheckConnection	(	LevelGridNode	node,
		int	dir
	)

static

Returns if node is connected to it's neighbour in the specified direction.

override int CountNodes ( )

virtual

Count nodes in the graph.

Note that this is, unless the graph type has overriden it, an O(n) operation.

Todo:: GridGraph should override this

Reimplemented from GridGraph.

override void DeserializeExtraInfo ( GraphSerializationContext ctx )

virtual

Deserializes graph type specific node data.

See Also: SerializeExtraInfo

Reimplemented from GridGraph.

override void ErodeWalkableArea	(	int	xmin,
		int	zmin,
		int	xmax,
		int	zmax
	)

virtual

Erodes the walkable area.

See Also: erodeIterations

Reimplemented from GridGraph.

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

virtual

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

Parameters

position	The position to try to find a close node to
hint	Can be passed to enable some graph generators to find the nearest node faster.
constraint	Can for example tell the function to try to return a walkable node. If you do not get a good node back, consider calling GetNearestForce.

Reimplemented from GridGraph.

override NNInfo GetNearestForce	(	Vector3	position,
		NNConstraint	constraint
	)

virtual

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

Returns: an NNInfo. This method will only return an empty NNInfo if there are no nodes which comply with the specified constraint.

Reimplemented from GridGraph.

LevelGridNode GetNearestNode	(	Vector3	position,
		int	x,
		int	z,
		NNConstraint	constraint
	)

private

override GridNodeBase GetNeighbourAlongDirection	(	GridNodeBase	node,
		int	direction
	)

protectedvirtual

Utility method used by Linecast.

Required since LevelGridNode does not inherit from GridNode. Lots of ugly casting but it was better than massive code duplication.

Returns null if the node has no connection in that direction

Reimplemented from GridGraph.

override void GetNodes ( GraphNodeDelegateCancelable del )

virtual

Calls a delegate with all nodes in the graph.

This is the primary way of "looping" through all nodes in a graph.

This function should not change anything in the graph structure.

myGraph.GetNodes ((node) => {
    Debug.Log ("I found a node at position " + (Vector3)node.Position);
    return true;
});

Reimplemented from GridGraph.

override void OnDestroy ( )

virtual

This function will be called when this graph is destroyed.

Reimplemented from GridGraph.

override void OnDrawGizmos ( bool drawNodes )

virtual

Draw gizmos for the graph.

Reimplemented from GridGraph.

override void PostDeserialization ( )

virtual

Called after all deserialization has been done for all graphs.

Can be used to set up more graph data which is not serialized

Reimplemented from GridGraph.

bool RecalculateCell	(	int	x,
		int	z,
		bool	preserveExistingNodes
	)

Recalculates single cell.

Parameters

x	X coordinate of the cell
z	Z coordinate of the cell
preserveExistingNodes	If true, nodes will be reused, this can be used to preserve e.g penalty when recalculating

Returns: If new layers or nodes were added. If so, you need to call AstarPath.active.DataUpdate() after this function to make sure pathfinding works correctly for them (when doing a scan, that function does not need to be called however).

Note: Connections are not recalculated for the nodes.

void RemoveGridGraphFromStatic ( )

private

override void ScanInternal ( OnScanStatus statusCallback )

virtual

Scans the graph, called from AstarPath.ScanLoop.

Override this function to implement custom scanning logic The statusCallback may be optionally called to show progress info in the editor

Reimplemented from GridGraph.

override void SerializeExtraInfo ( GraphSerializationContext ctx )

virtual

Serializes graph type specific node data.

This function can be overriden to serialize extra node information (or graph information for that matter) which cannot be serialized using the standard serialization. Serialize the data in any way you want and return a byte array. When loading, the exact same byte array will be passed to the DeserializeExtraInfo function.
These functions will only be called if node serialization is enabled.

Reimplemented from GridGraph.

new void UpdateArea ( GraphUpdateObject o )

virtual void UpdatePenalty ( LevelGridNode node )

virtual

Updates penalty for the node.

This function sets penalty to zero (0) and then adjusts it if penaltyPosition is set to true.

Member Data Documentation

float characterHeight = 0.4F

Nodes with a short distance to the node above it will be set unwalkable.

int lastScannedDepth

package

int lastScannedWidth

package

int layerCount

Number of layers.

Warning: Do not modify this variable

float mergeSpanRange = 0.5F

If two layered nodes are too close, they will be merged.

new LevelGridNode [] nodes

Property Documentation

override bool uniformWidthDepthGrid

get

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

/Users/arong/Unity/a-pathfinding-project/Assets/AstarPathfindingProject/Generators/LayerGridGraphGenerator.cs

Detailed Description

Public Member Functions

Static Public Member Functions

Public Attributes

Protected Member Functions

Package Attributes

Properties

Private Member Functions

Additional Inherited Members

Member Function Documentation

Member Data Documentation

Property Documentation