NavMeshGraph Class Reference

Generates graphs based on navmeshes. More...

Detailed Description

Generates graphs based on navmeshes.

Navmeshes are meshes where each triangle defines a walkable area. These are great because the AI can get so much more information on how it can walk. Polygons instead of points mean that the funnel smoother can produce really nice looking paths and the graphs are also really fast to search and have a low memory footprint because fewer nodes are usually needed to describe the same area compared to grid graphs.

See also

Pathfinding.RecastGraph

Public Member Functions
override GraphTransform	CalculateTransform ()
	Returns a new transform which transforms graph space to world space. More...
void	ScanInternal (string objMeshPath)
	Scans the graph using the path to an .obj mesh. More...
Public Member Functions inherited from NavmeshBase
void	EndBatchTileUpdate ()
	End batch updating of tiles. More...
override NNInfoInternal	GetNearest (Vector3 position, NNConstraint constraint, GraphNode hint)
	Returns the nearest node to a position using the specified NNConstraint. More...
override NNInfoInternal	GetNearestForce (Vector3 position, NNConstraint constraint)
	Returns the nearest node to a position using the specified constraint . More...
override void	GetNodes (System.Action< GraphNode > action)
	Calls a delegate with all nodes in the graph. More...
NavmeshTile	GetTile (int x, int z)
	Tile at the specified x, z coordinate pair. More...
Bounds	GetTileBounds (IntRect rect)
	Returns an XZ bounds object with the bounds of a group of tiles. More...
Bounds	GetTileBounds (int x, int z, int width=1, int depth=1)
	Returns an XZ bounds object with the bounds of a group of tiles. More...
Bounds	GetTileBoundsInGraphSpace (IntRect rect)
Bounds	GetTileBoundsInGraphSpace (int x, int z, int width=1, int depth=1)
	Returns an XZ bounds object with the bounds of a group of tiles in graph space. More...
void	GetTileCoordinates (int tileIndex, out int x, out int z)
	Tile coordinates from a tile index. More...
Int2	GetTileCoordinates (Vector3 position)
	Returns the tile coordinate which contains the specified position. More...
NavmeshTile []	GetTiles ()
	All tiles. More...
IntRect	GetTouchingTiles (Bounds bounds)
	Returns a rect containing the indices of all tiles touching the specified bounds. More...
IntRect	GetTouchingTilesInGraphSpace (Rect rect)
	Returns a rect containing the indices of all tiles touching the specified bounds. More...
IntRect	GetTouchingTilesRound (Bounds bounds)
	Returns a rect containing the indices of all tiles by rounding the specified bounds to tile borders. More...
Int3	GetVertex (int index)
	Vertex coordinate for the specified vertex index. More...
int	GetVertexArrayIndex (int index)
Int3	GetVertexInGraphSpace (int index)
	Vertex coordinate in graph space for the specified vertex index. More...
bool	Linecast (Vector3 origin, Vector3 end)
	Returns if there is an obstacle between origin and end on the graph. More...
bool	Linecast (Vector3 origin, Vector3 end, GraphNode hint, out GraphHitInfo hit)
	Returns if there is an obstacle between origin and end on the graph. More...
bool	Linecast (Vector3 origin, Vector3 end, GraphNode hint)
	Returns if there is an obstacle between origin and end on the graph. More...
bool	Linecast (Vector3 origin, Vector3 end, GraphNode hint, out GraphHitInfo hit, List< GraphNode > trace)
	Returns if there is an obstacle between origin and end on the graph. More...
override void	OnDrawGizmos (Pathfinding.Util.RetainedGizmos gizmos, bool drawNodes)
GraphNode	PointOnNavmesh (Vector3 position, NNConstraint constraint)
	Finds the first node which contains position. More...
override void	RelocateNodes (Matrix4x4 deltaMatrix)
	Moves the nodes in this graph. More...
void	RelocateNodes (GraphTransform newTransform)
	Moves the nodes in this graph. More...
void	ReplaceTile (int x, int z, Int3[] verts, int[] tris)
	Replace tile at index with nodes created from specified navmesh. More...
void	ReplaceTile (int x, int z, int w, int d, Int3[] verts, int[] tris)
	Replaces a tile with a new mesh. More...
void	StartBatchTileUpdate ()
	Start batch updating of tiles. More...
Public Member Functions inherited from NavGraph
virtual int	CountNodes ()
	Number of nodes in the graph. More...
NNInfoInternal	GetNearest (Vector3 position)
	Returns the nearest node to a position using the default NNConstraint. More...
NNInfoInternal	GetNearest (Vector3 position, NNConstraint constraint)
	Returns the nearest node to a position using the specified NNConstraint. More...
void	GetNodes (System.Func< GraphNode, bool > action)
	Calls a delegate with all nodes in the graph until the delegate returns false. More...
virtual void	OnDrawGizmos (RetainedGizmos gizmos, bool drawNodes)
	Draw gizmos for the graph. More...
void	RelocateNodes (Matrix4x4 oldMatrix, Matrix4x4 newMatrix)
	Moves nodes in this graph. More...
void	Scan ()
	Scan the graph. More...
void	ScanGraph ()
	Scan the graph. More...
void	SetMatrix (Matrix4x4 m)
	Use to set both matrix and inverseMatrix at the same time. More...

Static Public Member Functions
static void	UpdateArea (GraphUpdateObject o, INavmeshHolder graph)
Static Public Member Functions inherited from NavmeshBase
static int	GetTileIndex (int index)
	Tile index from a vertex index. More...
static bool	Linecast (NavmeshBase graph, Vector3 origin, Vector3 end, GraphNode hint, out GraphHitInfo hit)
	Returns if there is an obstacle between origin and end on the graph. More...
static bool	Linecast (NavmeshBase graph, Vector3 origin, Vector3 end, GraphNode hint, out GraphHitInfo hit, List< GraphNode > trace)
	Returns if there is an obstacle between origin and end on the graph. More...

Public Attributes
Vector3	offset
	Offset in world space. More...
bool	recalculateNormals = true
	Determines how normals are calculated. More...
Vector3	rotation
	Rotation in degrees. More...
float	scale = 1
	Scale of the graph. More...
Mesh	sourceMesh
	Mesh to construct navmesh from. More...
Public Attributes inherited from NavmeshBase
Vector3	forcedBoundsSize = new Vector3(100, 40, 100)
	Size of the bounding box. More...
bool	nearestSearchOnlyXZ
	Perform nearest node searches in XZ space only. More...
System.Action< NavmeshTile[]>	OnRecalculatedTiles
	Called when tiles have been completely recalculated. More...
bool	showMeshOutline = true
	Show an outline of the polygons in the Unity Editor. More...
bool	showMeshSurface
	Show the surface of the navmesh. More...
bool	showNodeConnections
	Show the connections between the polygons in the Unity Editor. More...
const int	TileIndexMask = 0x7FFFF
const int	TileIndexOffset = 12
int	tileXCount
	Number of tiles along the X-axis. More...
int	tileZCount
	Number of tiles along the Z-axis. More...
GraphTransform	transform = new GraphTransform(Matrix4x4.identity)
	Determines how the graph transforms graph space to world space. More...
const int	VertexIndexMask = 0xFFF
Public Attributes inherited from NavGraph
AstarPath	active
	Reference to the AstarPath object in the scene. More...
bool	drawGizmos = true
	Enable to draw gizmos in the Unity scene view. More...
uint	graphIndex
	Index of the graph, used for identification purposes. More...
Guid	guid
	Used as an ID of the graph, considered to be unique. More...
bool	infoScreenOpen
	Used in the editor to check if the info screen is open. More...
uint	initialPenalty
	Default penalty to apply to all nodes. More...
Matrix4x4	inverseMatrix = Matrix4x4.identity
	Inverse of matrix. More...
Matrix4x4	matrix = Matrix4x4.identity
	A matrix for translating/rotating/scaling the graph. More...
string	name
	Name of the graph. More...
bool	open
	Is the graph open in the editor. More...

Protected Member Functions
override void	DeserializeSettingsCompatibility (GraphSerializationContext ctx)
	An old format for serializing settings. More...
override IEnumerable< Progress >	ScanInternal ()
	Internal method to scan the graph. More...
Protected Member Functions inherited from NavmeshBase
void	ClearTiles (int x, int z, int w, int d)
	Clear all tiles within the rectangle with one corner at (x,z), width w and depth d. More...
void	ConnectTiles (NavmeshTile tile1, NavmeshTile tile2)
	Generate connections between the two tiles. More...
void	ConnectTileWithNeighbours (NavmeshTile tile, bool onlyUnflagged=false)
TriangleMeshNode []	CreateNodes (int[] tris, int tileIndex, uint graphIndex)
override void	DeserializeExtraInfo (GraphSerializationContext ctx)
	Deserializes graph type specific node data. More...
void	FillWithEmptyTiles ()
	Fills graph with tiles created by NewEmptyTile. More...
NavmeshTile	NewEmptyTile (int x, int z)
	Creates a single new empty tile. More...
override void	OnDestroy ()
	Function for cleaning up references. More...
override void	PostDeserialization (GraphSerializationContext ctx)
	Called after all deserialization has been done for all graphs. More...
void	RemoveConnectionsFromTile (NavmeshTile tile)
void	RemoveConnectionsFromTo (NavmeshTile a, NavmeshTile b)
override void	SerializeExtraInfo (GraphSerializationContext ctx)
	Serializes Node Info. More...
Protected Member Functions inherited from NavGraph
virtual void	DestroyAllNodes ()
	Destroys all nodes in the graph. More...
void	DrawUnwalkableNodes (float size)

Properties
override float	MaxTileConnectionEdgeDistance [get]
override bool	RecalculateNormals [get]
override float	TileWorldSizeX [get]
override float	TileWorldSizeZ [get]
Properties inherited from NavmeshBase
abstract float	MaxTileConnectionEdgeDistance [get]
	Maximum (vertical) distance between the sides of two nodes for them to be connected across a tile edge. More...
abstract bool	RecalculateNormals [get]
	Determines how normals are calculated. More...
abstract float	TileWorldSizeX [get]
	Size of a tile in world units along the X axis. More...
abstract float	TileWorldSizeZ [get]
	Size of a tile in world units along the Z axis. More...
GraphTransform ITransformedGraph.	transform [get]
Properties inherited from NavGraph
bool	exists [get]
	True if the graph exists, false if it has been destroyed. More...
Properties inherited from ITransformedGraph
GraphTransform	transform [get]

Private Member Functions
GraphUpdateThreading IUpdatableGraph.	CanUpdateAsync (GraphUpdateObject o)
void IUpdatableGraph.	UpdateArea (GraphUpdateObject o)
	Updates an area using the specified #GraphUpdateObject. More...
void IUpdatableGraph.	UpdateAreaInit (GraphUpdateObject o)
	May be called on the Unity thread before starting the update. More...
void IUpdatableGraph.	UpdateAreaPost (GraphUpdateObject o)
	May be called on the Unity thread after executing the update. More...

Additional Inherited Members
Static Protected Member Functions inherited from NavmeshBase
static void	CreateNodeConnections (TriangleMeshNode[] nodes)
	Create connections between all nodes. More...
Protected Attributes inherited from NavmeshBase
NavmeshTile []	tiles
	All tiles. More...

Member Function Documentation

CalculateTransform()

override GraphTransform CalculateTransform ( )

virtual

Returns a new transform which transforms graph space to world space.

Does not update the transform field.

See also

RelocateNodes(GraphTransform)

Implements NavmeshBase.

CanUpdateAsync()

GraphUpdateThreading IUpdatableGraph. CanUpdateAsync ( GraphUpdateObject  o )

private

Implements IUpdatableGraph.

DeserializeSettingsCompatibility()

override void DeserializeSettingsCompatibility ( GraphSerializationContext  ctx )

protectedvirtual

An old format for serializing settings.

Deprecated:

This is deprecated now, but the deserialization code is kept to avoid loosing data when upgrading from older versions.

Reimplemented from NavGraph.

ScanInternal() [1/2]

void ScanInternal

(

string

objMeshPath

)

Scans the graph using the path to an .obj mesh.

ScanInternal() [2/2]

override IEnumerable<Progress> ScanInternal ( )

protectedvirtual

Internal method to scan the graph.

Called from AstarPath.ScanAsync. Override this function to implement custom scanning logic. Progress objects can be yielded to show progress info in the editor and to split up processing over several frames when using async scanning.

Implements NavGraph.

UpdateArea() [1/2]

void IUpdatableGraph. UpdateArea ( GraphUpdateObject  o )

private

Updates an area using the specified #GraphUpdateObject.

Notes to implementators. This function should (in order):

1. Call o.WillUpdateNode on the GUO for every node it will update, it is important that this is called BEFORE any changes are made to the nodes.
2. Update walkabilty using special settings such as the usePhysics flag used with the GridGraph.
3. Call Apply on the GUO for every node which should be updated with the GUO.
4. Update connectivity info if appropriate (GridGraphs updates connectivity, but most other graphs don't since then the connectivity cannot be recovered later).

Implements IUpdatableGraph.

UpdateArea() [2/2]

static void UpdateArea ( GraphUpdateObject  o, INavmeshHolder  graph  )

static

UpdateAreaInit()

void IUpdatableGraph. UpdateAreaInit ( GraphUpdateObject  o )

private

May be called on the Unity thread before starting the update.

See also

CanUpdateAsync

Implements IUpdatableGraph.

UpdateAreaPost()

void IUpdatableGraph. UpdateAreaPost ( GraphUpdateObject  o )

private

May be called on the Unity thread after executing the update.

See also

CanUpdateAsync

Implements IUpdatableGraph.

Member Data Documentation

offset

Vector3 offset

Offset in world space.

recalculateNormals

bool recalculateNormals = true

Determines how normals are calculated.

Disable for spherical graphs or other complicated surfaces that allow the agents to e.g walk on walls or ceilings.

By default the normals of the mesh will be flipped so that they point as much as possible in the upwards direction. The normals are important when connecting adjacent nodes. Two adjacent nodes will only be connected if they are oriented the same way. This is particularly important if you have a navmesh on the walls or even on the ceiling of a room. Or if you are trying to make a spherical navmesh. If you do one of those things then you should set disable this setting and make sure the normals in your source mesh are properly set.

If you for example take a look at the image below. In the upper case then the nodes on the bottom half of the mesh haven't been connected with the nodes on the upper half because the normals on the lower half will have been modified to point inwards (as that is the direction that makes them face upwards the most) while the normals on the upper half point outwards. This causes the nodes to not connect properly along the seam. When this option is set to false instead the nodes are connected properly as in the original mesh all normals point outwards.

The default value of this field is true to reduce the risk for errors in the common case. If a mesh is supplied that has all normals pointing downwards and this option is false, then some methods like PointOnNavmesh will not work correctly as they assume that the normals point upwards. For a more complicated surface like a spherical graph those methods make no sense anyway as there is no clear definition of what it means to be "inside" a triangle when there is no clear up direction.

rotation

Vector3 rotation

Rotation in degrees.

scale

float scale = 1

Scale of the graph.

sourceMesh

Mesh sourceMesh

Mesh to construct navmesh from.

Property Documentation

MaxTileConnectionEdgeDistance

override float MaxTileConnectionEdgeDistance

getprotected

RecalculateNormals

override bool RecalculateNormals

getprotected

TileWorldSizeX

override float TileWorldSizeX

get

TileWorldSizeZ

override float TileWorldSizeZ

get

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

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