A* Pathfinding Project  3.8.10
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LayerGridGraph Class Reference

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< GraphNodeGetNodesInArea (Bounds b)
 All nodes inside the bounding box.
 
List< GraphNodeGetNodesInArea (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
positionThe position to try to find a close node to
hintCan be passed to enable some graph generators to find the nearest node faster.
constraintCan 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
xX coordinate of the cell
zZ coordinate of the cell
preserveExistingNodesIf 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: