Automatically generates navmesh graphs based on world geometry. More...

Detailed Description

Automatically generates navmesh graphs based on world geometry.

The recast graph is based on Recast (http://code.google.com/p/recastnavigation/).
I have translated a good portion of it to C# to run it natively in Unity.

How a recast graph works

When generating a recast graph what happens is that the world is voxelized. You can think of this as constructing an approximation of the world out of lots of boxes. If you have played Minecraft it looks very similar (but with smaller boxes).

The Recast process is described as follows:

The voxel mold is build from the input triangle mesh by rasterizing the triangles into a multi-layer heightfield. Some simple filters are then applied to the mold to prune out locations where the character would not be able to move.
The walkable areas described by the mold are divided into simple overlayed 2D regions. The resulting regions have only one non-overlapping contour, which simplifies the final step of the process tremendously.
The navigation polygons are peeled off from the regions by first tracing the boundaries and then simplifying them. The resulting polygons are finally converted to convex polygons which makes them perfect for pathfinding and spatial reasoning about the level.

It works exactly like that in the C# version as well, except that everything is triangulated to triangles instead of n-gons. The recast generation process usually works directly on the visiable geometry in the world, this is usually a good thing, because world geometry is usually more detailed than the colliders. You can however specify that colliders should be rasterized, if you have very detailed world geometry, this can speed up the scan.

Check out the second part of the Get Started Tutorial which discusses recast graphs.

Exporting for manual editing

In the editor there is a button for exporting the generated graph to a .obj file. Usually the generation process is good enough for the game directly, but in some cases you might want to edit some minor details. So you can export the graph to a .obj file, open it in your favourite 3D application, edit it, and export it to a mesh which Unity can import. You can then use that mesh in a navmesh graph.

Since many 3D modelling programs use different axis systems (unity uses X=right, Y=up, Z=forward), it can be a bit tricky to get the rotation and scaling right. For blender for example, what you have to do is to first import the mesh using the .obj importer. Don't change anything related to axes in the settings. Then select the mesh, open the transform tab (usually the thin toolbar to the right of the 3D view) and set Scale -> Z to -1. If you transform it using the S (scale) hotkey, it seems to set both Z and Y to -1 for some reason. Then make the edits you need and export it as an .obj file to somewhere in the Unity project. But this time, edit the setting named "Forward" to "Z forward" (not -Z as it is per default).

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 Types
enum	RelevantGraphSurfaceMode { DoNotRequire, OnlyForCompletelyInsideTile, RequireForAll }

Public Member Functions
override GraphTransform	CalculateTransform ()
	Returns a new transform which transforms graph space to world space. More...

Vector3	ClosestPointOnNode (TriangleMeshNode node, Vector3 pos)
	Returns the closest point of the node. More...

bool	ContainsPoint (TriangleMeshNode node, Vector3 pos)
	Returns if the point is inside the node in XZ space. More...

void	SnapForceBoundsToScene ()
	Changes the bounds of the graph to precisely encapsulate all objects in the scene that can be included in the scanning process based on the settings. More...

Public Member Functions inherited from NavmeshBase
	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 a bounds object with the bounding box of a group of tiles. More...

Bounds	GetTileBounds (int x, int z, int width=1, int depth=1)
	Returns a bounds object with the bounding box 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, float margin=0)
	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, RetainedGizmos.RedrawScope redrawScope)

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	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. 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, RetainedGizmos.RedrawScope redrawScope)
	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...

Public Attributes
const int	BorderVertexMask = 1

const int	BorderVertexOffset = 31

float	cellSize = 0.5F
	Voxel sample size (x,z). More...

float	characterRadius = 1.5F
	Radius of the agent which will traverse the navmesh. More...

float	colliderRasterizeDetail = 10
	Controls detail on rasterization of sphere and capsule colliders. More...

float	contourMaxError = 2F
	Max distance from simplified edge to real edge. More...

int	editorTileSize = 128
	Size in voxels of a single tile. More...

Vector3	forcedBoundsCenter
	Center of the bounding box. More...

LayerMask	mask = -1
	Layer mask which filters which objects to include. More...

float	maxEdgeLength = 20
	Longer edges will be subdivided. More...

float	maxSlope = 30
	Max slope in degrees the character can traverse. More...

float	minRegionSize = 3
	Minumum region size. More...

bool	rasterizeColliders
	Use colliders to calculate the navmesh. More...

bool	rasterizeMeshes = true
	Use scene meshes to calculate the navmesh. More...

bool	rasterizeTerrain = true
	Include the Terrain in the scene. More...

bool	rasterizeTrees = true
	Rasterize tree colliders on terrains. More...

RelevantGraphSurfaceMode	relevantGraphSurfaceMode = RelevantGraphSurfaceMode.DoNotRequire
	Require every region to have a RelevantGraphSurface component inside it. More...

Vector3	rotation
	Rotation of the graph in degrees. More...

bool	scanEmptyGraph
	If true, scanning the graph will yield a completely empty graph. More...

List< string >	tagMask = new List<string>()
	Objects tagged with any of these tags will be rasterized. More...

int	terrainSampleSize = 3
	Controls how large the sample size for the terrain is. More...

int	tileSizeX = 128
	Size of a tile along the X axis in voxels. More...

int	tileSizeZ = 128
	Size of a tile along the Z axis in voxels. More...

bool	useTiles = true
	If true, divide the graph into tiles, otherwise use a single tile covering the whole graph. More...

float	walkableClimb = 0.5F
	Height the character can climb. More...

float	walkableHeight = 2F
	Character height. More...

Public Attributes inherited from NavmeshBase
bool	enableNavmeshCutting = true
	Should navmesh cuts affect this graph. More...

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 = true
	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
NavmeshTile	BuildTileMesh (Voxelize vox, int x, int z, int threadIndex=0)

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

IEnumerable< Progress >	ScanAllTiles ()

override IEnumerable< Progress >	ScanInternal ()
	Internal method to scan the graph. More...

Protected Member Functions inherited from NavmeshBase
void	ClearTile (int x, int z)
	Clear the tile at the specified coordinate. More...

void	ConnectTiles (NavmeshTile tile1, NavmeshTile tile2)
	Generate connections between the two tiles. More...

void	ConnectTileWithNeighbours (NavmeshTile tile, bool onlyUnflagged=false)

void	CreateNodes (TriangleMeshNode[] buffer, 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...

virtual void	DisposeUnmanagedData ()
	Cleans up any unmanaged data that the graph has. More...

void	DrawUnwalkableNodes (RetainedGizmos gizmos, float size)

virtual IEnumerable< Progress >	ScanInternal (bool async)
	Internal method to scan the graph. More...

Properties
float	CellHeight `[get]`

int	CharacterRadiusInVoxels `[get]`
	Convert character radius to a number of voxels. More...

Bounds	forcedBounds `[get]`
	World bounds for the graph. More...

override float	MaxTileConnectionEdgeDistance `[get]`

override bool	RecalculateNormals `[get]`

int	TileBorderSizeInVoxels `[get]`
	Number of extra voxels on each side of a tile to ensure accurate navmeshes near the tile border. More...

float	TileBorderSizeInWorldUnits `[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...

string IGraphInternals.	SerializedEditorSettings `[get, set]`

Properties inherited from IGraphInternals
string	SerializedEditorSettings `[get, set]`

Properties inherited from ITransformedGraph
GraphTransform	transform `[get]`

Private Member Functions
Bounds	CalculateTileBoundsWithBorder (int x, int z)

GraphUpdateThreading IUpdatableGraph.	CanUpdateAsync (GraphUpdateObject o)

List< RasterizationMesh >	CollectMeshes (Bounds bounds)

NavmeshTile	CreateTile (Voxelize vox, VoxelMesh mesh, int x, int z, int threadIndex)
	Create a tile at tile index x, z from the mesh. More...

void	InitializeTileInfo ()

List< RasterizationMesh > []	PutMeshesIntoTileBuckets (List< RasterizationMesh > meshes)
	Creates a list for every tile and adds every mesh that touches a tile to the corresponding list. More...

void IUpdatableGraph.	UpdateArea (GraphUpdateObject guo)
	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 guo)
	Called on the Unity thread to complete a graph update. More...

Private Attributes
Voxelize	globalVox

List< NavmeshTile >	stagingTiles = new List<NavmeshTile>()
	List of tiles that have been calculated in a graph update, but have not yet been added to the graph. More...

Additional Inherited Members
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...

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...

Package Attributes inherited from NavmeshBase
readonly NavmeshUpdates.NavmeshUpdateSettings	navmeshUpdateData
	Handles navmesh cutting. More...

Member Enumeration Documentation

◆ RelevantGraphSurfaceMode

enum RelevantGraphSurfaceMode

strong

Enumerator

DoNotRequire

No RelevantGraphSurface components are required anywhere.

OnlyForCompletelyInsideTile

Any surfaces that are completely inside tiles need to have a RelevantGraphSurface component positioned on that surface, otherwise it will be stripped away.

RequireForAll

All surfaces need to have one RelevantGraphSurface component positioned somewhere on the surface and in each tile that it touches, otherwise it will be stripped away.

Only tiles that have a RelevantGraphSurface component for that surface will keep it.

Member Function Documentation

◆ BuildTileMesh()

NavmeshTile BuildTileMesh	(	Voxelize	vox,
		int	x,
		int	z,
		int	threadIndex = `0`
	)

protected

◆ CalculateTileBoundsWithBorder()

Bounds CalculateTileBoundsWithBorder	(	int	x,
		int	z
	)

private

◆ 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.

◆ ClosestPointOnNode()

Vector3 ClosestPointOnNode	(	TriangleMeshNode	node,
		Vector3	pos
	)

Returns the closest point of the node.

Deprecated:: Use Pathfinding.TriangleMeshNode.ClosestPointOnNode instead

◆ CollectMeshes()

List<RasterizationMesh> CollectMeshes ( Bounds bounds )

private

◆ ContainsPoint()

bool ContainsPoint	(	TriangleMeshNode	node,
		Vector3	pos
	)

Returns if the point is inside the node in XZ space.

Deprecated:: Use Pathfinding.TriangleMeshNode.ContainsPoint instead

◆ CreateTile()

NavmeshTile CreateTile	(	Voxelize	vox,
		VoxelMesh	mesh,
		int	x,
		int	z,
		int	threadIndex
	)

private

Create a tile at tile index x, z from the mesh.

Version: Since version 3.7.6 the implementation is thread safe

◆ 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.

◆ InitializeTileInfo()

void InitializeTileInfo ( )

private

◆ PutMeshesIntoTileBuckets()

List<RasterizationMesh> [] PutMeshesIntoTileBuckets ( List< RasterizationMesh > meshes )

private

Creates a list for every tile and adds every mesh that touches a tile to the corresponding list.

◆ ScanAllTiles()

IEnumerable<Progress> ScanAllTiles ( )

protected

◆ ScanInternal()

override IEnumerable<Progress> ScanInternal ( )

protectedvirtual

Internal method to scan the graph.

Deprecated:: You should use ScanInternal(bool) instead.

Reimplemented from NavGraph.

◆ SnapForceBoundsToScene()

void SnapForceBoundsToScene ( )

Changes the bounds of the graph to precisely encapsulate all objects in the scene that can be included in the scanning process based on the settings.

Which objects are used depends on the settings. If an object would have affected the graph with the current settings if it would have been inside the bounds of the graph, it will be detected and the bounds will be expanded to contain that object.

This method corresponds to the 'Snap bounds to scene' button in the inspector.

See also: rasterizeMeshes; rasterizeTerrain; rasterizeColliders; mask; tagMask; forcedBoundsCenter; forcedBoundsSize

◆ UpdateArea()

void IUpdatableGraph. UpdateArea ( GraphUpdateObject o )

private

Updates an area using the specified #GraphUpdateObject.

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

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.
Update walkabilty using special settings such as the usePhysics flag used with the GridGraph.
Call Apply on the GUO for every node which should be updated with the GUO.
Update connectivity info if appropriate (GridGraphs updates connectivity, but most other graphs don't since then the connectivity cannot be recovered later).

Implements IUpdatableGraph.

◆ 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 guo )

private

Called on the Unity thread to complete a graph update.

Implements IUpdatableGraph.

Member Data Documentation

◆ BorderVertexMask

const int BorderVertexMask = 1

◆ BorderVertexOffset

const int BorderVertexOffset = 31

◆ cellSize

float cellSize = 0.5F

Voxel sample size (x,z).

When generating a recast graph what happens is that the world is voxelized. You can think of this as constructing an approximation of the world out of lots of boxes. If you have played Minecraft it looks very similar (but with smaller boxes).

The cell size is the width and depth of those boxes. The height of the boxes is usually much smaller and automatically calculated however. See CellHeight.

Lower values will yield higher quality navmeshes, however the graph will be slower to scan.

◆ characterRadius

float characterRadius = 1.5F

Radius of the agent which will traverse the navmesh.

The navmesh will be eroded with this radius.

◆ colliderRasterizeDetail

float colliderRasterizeDetail = 10

Controls detail on rasterization of sphere and capsule colliders.

This controls the number of rows and columns on the generated meshes. A higher value does not necessarily increase quality of the mesh, but a lower value will often speed it up.

You should try to keep this value as low as possible without affecting the mesh quality since that will yield the fastest scan times.

See also: rasterizeColliders

◆ contourMaxError

float contourMaxError = 2F

Max distance from simplified edge to real edge.

This value is measured in voxels. So with the default value of 2 it means that the final navmesh contour may be at most 2 voxels (i.e 2 times cellSize) away from the border that was calculated when voxelizing the world. A higher value will yield a more simplified and cleaner navmesh while a lower value may capture more details. However a too low value will cause the individual voxels to be visible (see image below).

See also: cellSize

◆ editorTileSize

int editorTileSize = 128

Size in voxels of a single tile.

This is the width of the tile.

A large tile size can be faster to initially scan (but beware of out of memory issues if you try with a too large tile size in a large world) smaller tile sizes are (much) faster to update.

Different tile sizes can affect the quality of paths. It is often good to split up huge open areas into several tiles for better quality paths, but too small tiles can also lead to effects looking like invisible obstacles. For more information about this take a look at Notes about navmesh graphs. Usually it is best to experiment and see what works best for your game.

When scanning a recast graphs individual tiles can be calculated in parallel which can make it much faster to scan large worlds. When you want to recalculate a part of a recast graph, this can only be done on a tile-by-tile basis which means that if you often try to update a region of the recast graph much smaller than the tile size, then you will be doing a lot of unnecessary calculations. However if you on the other hand update regions of the recast graph that are much larger than the tile size then it may be slower than necessary as there is some overhead in having lots of tiles instead of a few larger ones (not that much though).

Recommended values are between 64 and 256, but these are very soft limits. It is possible to use both larger and smaller values.

◆ forcedBoundsCenter

Vector3 forcedBoundsCenter

Center of the bounding box.

Scanning will only be done inside the bounding box

◆ globalVox

Voxelize globalVox

private

◆ mask

LayerMask mask = -1

Layer mask which filters which objects to include.

See also: tagMask

◆ maxEdgeLength

float maxEdgeLength = 20

Longer edges will be subdivided.

Reducing this value can sometimes improve path quality since similarly sized triangles yield better paths than really large and really triangles small next to each other. However it will also add a lot more nodes which will make pathfinding slower. For more information about this take a look at Notes about navmesh graphs.

◆ maxSlope

float maxSlope = 30

Max slope in degrees the character can traverse.

◆ minRegionSize

float minRegionSize = 3

Minumum region size.

Small regions will be removed from the navmesh. Measured in square world units (square meters in most games).

If a region is adjacent to a tile border, it will not be removed even though it is small since the adjacent tile might join it to form a larger region.

◆ rasterizeColliders

bool rasterizeColliders

Use colliders to calculate the navmesh.

◆ rasterizeMeshes

bool rasterizeMeshes = true

Use scene meshes to calculate the navmesh.

◆ rasterizeTerrain

bool rasterizeTerrain = true

Include the Terrain in the scene.

◆ rasterizeTrees

bool rasterizeTrees = true

Rasterize tree colliders on terrains.

If the tree prefab has a collider, that collider will be rasterized. Otherwise a simple box collider will be used and the script will try to adjust it to the tree's scale, it might not do a very good job though so an attached collider is preferable.

Note: It seems that Unity will only generate tree colliders at runtime when the game is started. For this reason, this graph will not pick up tree colliders when scanned outside of play mode but it will pick them up if the graph is scanned when the game has started. If it still does not pick them up make sure that the trees actually have colliders attached to them and that the tree prefabs are in the correct layer (the layer should be included in the layer mask).

See also: rasterizeTerrain; colliderRasterizeDetail

◆ relevantGraphSurfaceMode

RelevantGraphSurfaceMode relevantGraphSurfaceMode = RelevantGraphSurfaceMode.DoNotRequire

Require every region to have a RelevantGraphSurface component inside it.

A RelevantGraphSurface component placed in the scene specifies that the navmesh region it is inside should be included in the navmesh.

If this is set to OnlyForCompletelyInsideTile a navmesh region is included in the navmesh if it has a RelevantGraphSurface inside it, or if it is adjacent to a tile border. This can leave some small regions which you didn't want to have included because they are adjacent to tile borders, but it removes the need to place a component in every single tile, which can be tedious (see below).

If this is set to RequireForAll a navmesh region is included only if it has a RelevantGraphSurface inside it. Note that even though the navmesh looks continous between tiles, the tiles are computed individually and therefore you need a RelevantGraphSurface component for each region and for each tile.

In the above image, the mode OnlyForCompletelyInsideTile was used. Tile borders are highlighted in black. Note that since all regions are adjacent to a tile border, this mode didn't remove anything in this case and would give the same result as DoNotRequire. The RelevantGraphSurface component is shown using the green gizmo in the top-right of the blue plane.

In the above image, the mode RequireForAll was used. No tiles were used. Note that the small region at the top of the orange cube is now gone, since it was not the in the same region as the relevant graph surface component. The result would have been identical with OnlyForCompletelyInsideTile since there are no tiles (or a single tile, depending on how you look at it).

The mode RequireForAll was used here. Since there is only a single RelevantGraphSurface component, only the region it was in, in the tile it is placed in, will be enabled. If there would have been several RelevantGraphSurface in other tiles, those regions could have been enabled as well.

Here another tile size was used along with the OnlyForCompletelyInsideTile. Note that the region on top of the orange cube is gone now since the region borders do not intersect that region (and there is no RelevantGraphSurface component inside it).

Note: When not using tiles. OnlyForCompletelyInsideTile is equivalent to RequireForAll.

◆ rotation

Vector3 rotation

Rotation of the graph in degrees.

◆ scanEmptyGraph

bool scanEmptyGraph

If true, scanning the graph will yield a completely empty graph.

Useful if you want to replace the graph with a custom navmesh for example

◆ stagingTiles

List<NavmeshTile> stagingTiles = new List<NavmeshTile>()

private

List of tiles that have been calculated in a graph update, but have not yet been added to the graph.

When updating the graph in a separate thread, large changes cannot be made directly to the graph as other scripts might use the graph data structures at the same time in another thread. So the tiles are calculated, but they are not yet connected to the existing tiles that will be done in UpdateAreaPost which runs in the Unity thread.

◆ tagMask

List<string> tagMask = new List<string>()

Objects tagged with any of these tags will be rasterized.

Note that this extends the layer mask, so if you only want to use tags, set mask to 'Nothing'.

See also: mask

◆ terrainSampleSize

int terrainSampleSize = 3

Controls how large the sample size for the terrain is.

A higher value is faster to scan but less accurate

◆ tileSizeX

int tileSizeX = 128

Size of a tile along the X axis in voxels.

This is the width of the tile.

A large tile size can be faster to initially scan (but beware of out of memory issues if you try with a too large tile size in a large world) smaller tile sizes are (much) faster to update.

Different tile sizes can affect the quality of paths. It is often good to split up huge open areas into several tiles for better quality paths, but too small tiles can also lead to effects looking like invisible obstacles. For more information about this take a look at Notes about navmesh graphs. Usually it is best to experiment and see what works best for your game.

When scanning a recast graphs individual tiles can be calculated in parallel which can make it much faster to scan large worlds. When you want to recalculate a part of a recast graph, this can only be done on a tile-by-tile basis which means that if you often try to update a region of the recast graph much smaller than the tile size, then you will be doing a lot of unnecessary calculations. However if you on the other hand update regions of the recast graph that are much larger than the tile size then it may be slower than necessary as there is some overhead in having lots of tiles instead of a few larger ones (not that much though).

Recommended values are between 64 and 256, but these are very soft limits. It is possible to use both larger and smaller values.

Warning: Do not modify, it is set from editorTileSize at Scan

See also: tileSizeZ

◆ tileSizeZ

int tileSizeZ = 128

Size of a tile along the Z axis in voxels.

This is the width of the tile.

A large tile size can be faster to initially scan (but beware of out of memory issues if you try with a too large tile size in a large world) smaller tile sizes are (much) faster to update.

Different tile sizes can affect the quality of paths. It is often good to split up huge open areas into several tiles for better quality paths, but too small tiles can also lead to effects looking like invisible obstacles. For more information about this take a look at Notes about navmesh graphs. Usually it is best to experiment and see what works best for your game.

When scanning a recast graphs individual tiles can be calculated in parallel which can make it much faster to scan large worlds. When you want to recalculate a part of a recast graph, this can only be done on a tile-by-tile basis which means that if you often try to update a region of the recast graph much smaller than the tile size, then you will be doing a lot of unnecessary calculations. However if you on the other hand update regions of the recast graph that are much larger than the tile size then it may be slower than necessary as there is some overhead in having lots of tiles instead of a few larger ones (not that much though).

Recommended values are between 64 and 256, but these are very soft limits. It is possible to use both larger and smaller values.

Warning: Do not modify, it is set from editorTileSize at Scan

See also: tileSizeX

◆ useTiles

bool useTiles = true

If true, divide the graph into tiles, otherwise use a single tile covering the whole graph.

Since: Since 4.1 the default value is true.

◆ walkableClimb

float walkableClimb = 0.5F

Height the character can climb.

◆ walkableHeight

float walkableHeight = 2F

Character height.

Property Documentation

◆ CellHeight

float CellHeight

getprivate

◆ CharacterRadiusInVoxels

int CharacterRadiusInVoxels

getprivate

Convert character radius to a number of voxels.

◆ forcedBounds

Bounds forcedBounds

get

World bounds for the graph.

Defined as a bounds object with size forcedBoundsSize and centered at forcedBoundsCenter

Deprecated:: Obsolete since this is not accurate when the graph is rotated (rotation was not supported when this property was created)

◆ MaxTileConnectionEdgeDistance

override float MaxTileConnectionEdgeDistance

getprotected

◆ RecalculateNormals

override bool RecalculateNormals

getprotected

◆ TileBorderSizeInVoxels

int TileBorderSizeInVoxels

getprivate

Number of extra voxels on each side of a tile to ensure accurate navmeshes near the tile border.

The width of a tile is expanded by 2 times this value (1x to the left and 1x to the right)

◆ TileBorderSizeInWorldUnits

float TileBorderSizeInWorldUnits

getprivate

◆ TileWorldSizeX

override float TileWorldSizeX

get

◆ TileWorldSizeZ

override float TileWorldSizeZ

get

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

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

Detailed Description

How a recast graph works

Exporting for manual editing

Public Types

Public Member Functions

Public Attributes

Protected Member Functions

Properties

Private Member Functions

Private Attributes

Additional Inherited Members

Member Enumeration Documentation

◆ RelevantGraphSurfaceMode

Member Function Documentation

◆ BuildTileMesh()

◆ CalculateTileBoundsWithBorder()

◆ CalculateTransform()

◆ CanUpdateAsync()

◆ ClosestPointOnNode()

◆ CollectMeshes()

◆ ContainsPoint()

◆ CreateTile()

◆ DeserializeSettingsCompatibility()

◆ InitializeTileInfo()

◆ PutMeshesIntoTileBuckets()

◆ ScanAllTiles()

◆ ScanInternal()

◆ SnapForceBoundsToScene()

◆ UpdateArea()

◆ UpdateAreaInit()

◆ UpdateAreaPost()

Member Data Documentation

◆ BorderVertexMask

◆ BorderVertexOffset

◆ cellSize

◆ characterRadius

◆ colliderRasterizeDetail

◆ contourMaxError

◆ editorTileSize

◆ forcedBoundsCenter

◆ globalVox

◆ mask

◆ maxEdgeLength

◆ maxSlope

◆ minRegionSize

◆ rasterizeColliders

◆ rasterizeMeshes

◆ rasterizeTerrain

◆ rasterizeTrees

◆ relevantGraphSurfaceMode

◆ rotation

◆ scanEmptyGraph

◆ stagingTiles

◆ tagMask

◆ terrainSampleSize

◆ tileSizeX

◆ tileSizeZ

◆ useTiles

◆ walkableClimb

◆ walkableHeight

Property Documentation

◆ CellHeight

◆ CharacterRadiusInVoxels

◆ forcedBounds

◆ MaxTileConnectionEdgeDistance

◆ RecalculateNormals

◆ TileBorderSizeInVoxels

◆ TileBorderSizeInWorldUnits

◆ TileWorldSizeX

◆ TileWorldSizeZ