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  3. dtNavMesh

dtNavMesh

A navigation mesh based on tiles of convex polygons.

Unreal Engine C++ API Reference > Runtime > Navmesh > Detour

References

   
Module Navmesh
Header /Engine/Source/Runtime/Navmesh/Public/Detour/DetourNavMesh.h
Include #include "Detour/DetourNavMesh.h"

Syntax

class dtNavMesh

Remarks

A navigation mesh based on tiles of convex polygons.

The navigation mesh consists of one or more tiles defining three primary types of structural data:

A polygon mesh which defines most of the navigation graph. (See rcPolyMesh for its structure.) A detail mesh used for determining surface height on the polygon mesh. (See rcPolyMeshDetail for its structure.) Off-mesh connections, which define custom point-to-point edges within the navigation graph.

The general build process is as follows:

Create rcPolyMesh and rcPolyMeshDetail data using the Recast build pipeline.

Optionally, create off-mesh connection data.

Combine the source data into a dtNavMeshCreateParams structure.

Create a tile data array using dtCreateNavMeshData().

Allocate at dtNavMesh object and initialize it. (For single tile navigation meshes, the tile data is loaded during this step.)

For multi-tile navigation meshes, load the tile data using dtNavMesh::addTile().

Notes:

  • This class is usually used in conjunction with the dtNavMeshQuery class for pathfinding.
  • Technically, all navigation meshes are tiled. A 'solo' mesh is simply a navigation mesh initialized to have only a single tile.
  • This class does not implement any asynchronous methods. So the dtStatus result of all methods will always contain either a success or failure flag.

Variables

  Type Name Description
Public variable unsigned char[DT_MAX_AREAS] m_areaCostOrder  
Public variable int m_maxTiles Max number of tiles.
Public variable dtMeshTile * m_nextFree Freelist of tiles.
Public variable dtReal[3] m_orig Origin of the tile (0,0)
Public variable dtNavMeshParams m_params Current initialization params.
Public variable unsigned int m_polyBits Number of poly bits in the tile ID.
Public variable dtMeshTile ** m_posLookup Tile hash lookup.
Public variable unsigned int m_saltBits Number of salt bits in the tile ID.
Public variable unsigned int m_tileBits Number of tile bits in the tile ID.
Public variable dtReal m_tileHeight Dimensions of each tile.
Public variable int m_tileLutMask Tile hash lookup mask.
Public variable int m_tileLutSize Tile hash lookup size (must be pot).
Public variable dtMeshTile * m_tiles List of tiles.
Public variable dtReal m_tileWidth  

Constructors

  Type Name Description
Public function    

Destructors

  Type Name Description
Public function    

Functions

  Type Name Description
Public function dtStatus

addTile ( unsigned char* data,
int dataSize,
int flags,
dtTileRef lastRef,
dtTileRef* result
)

 Adds a tile to the navigation mesh.
Public function void

applyAreaCostOrder ( unsigned char* costOrder
)

  
Public function void

applyWorldOffset ( const dtReal* offset
)

 Shift navigation mesh by provided offset.
Public function Const void

calcTileLoc ( const dtReal* pos,
int* tx,
int* ty
)

 Calculates the tile grid location for the specified world position.
Public function Const unsigned int

decodeClusterIdTile ( dtClusterRef ref
)

 Extracts the tile's index from the specified cluster reference.
Public function Const void

decodePolyId ( dtPolyRef ref,
unsigned int& salt,
unsigned int& it,
unsigned int& ip
)

 Decodes a standard polygon reference. This function is generally meant for internal use only.
Public function Const unsigned int

decodePolyIdPoly ( dtPolyRef ref
)

 Extracts the polygon's index (within its tile) from the specified polygon reference.
Public function Const unsigned int

decodePolyIdSalt ( dtPolyRef ref
)

 Extracts a tile's salt value from the specified polygon reference.
Public function Const unsigned int

decodePolyIdTile ( dtPolyRef ref
)

 Extracts the tile's index from the specified polygon reference.
Public function Const dtPolyRef

encodePolyId ( unsigned int salt,
unsigned int it,
unsigned int ip
)

 Derives a standard polygon reference. This function is generally meant for internal use only.
Public function Const dtReal

getBVQuantFactor ( const unsigned char resolution
)

  
Public function Const dtClusterRef

getClusterRefBase ( const dtMeshTile* tile
)

 Gets the cluster reference for the tile's base cluster.
Public function dtLink &

getLink ( dtMeshTile* tile,
unsigned int linkIdx
)

 Helper for accessing links.
Public function Const const dtLink &

getLink ( const dtMeshTile* tile,
unsigned int linkIdx
)

  
Public function Const int The maximum number of tiles supported by the navigation mesh.
Public function Const bool

getNeighbourCoords ( const int x,
const int y,
const int side,
int& outX,
int& outY
)

  
Public function Const int

getNeighbourTilesCountAt ( const int x,
const int y,
const int side
)

 Returns neighbour tile count based on side of given tile.
Public function Const const dtOffMeshConnection *

getOffMeshConnectionByRef ( dtPolyRef ref
)

 Gets the specified off-mesh connection: point type.
Public function Const dtStatus

getOffMeshConnectionPolyEndPoints ( dtPolyRef prevRef,
dtPolyRef polyRef,
const dtReal* currentPos,
dtReal* startPos,
dtReal* endPos
)

 Gets the endpoints for an off-mesh connection, ordered by "direction of travel".
Public function Const const dtNavMeshParams * The navigation mesh initialization params.
Public function Const dtStatus

getPolyArea ( dtPolyRef ref,
unsigned char* resultArea
)

 Gets the user defined area for the specified polygon.
Public function Const dtStatus

getPolyFlags ( dtPolyRef ref,
unsigned short* resultFlags
)

 Gets the user defined flags for the specified polygon.
Public function Const dtPolyRef

getPolyRefBase ( const dtMeshTile* tile
)

 Gets the polygon reference for the tile's base polygon.
Public function Const unsigned int  
Public function Const const dtMeshTile *

getTile ( int i
)

 Gets the tile at the specified index.
Public function Const dtStatus

getTileAndPolyByRef ( const dtPolyRef ref,
const dtMeshTile** tile,
const dtPoly** poly
)

 Gets the tile and polygon for the specified polygon reference.
Public function Const void

getTileAndPolyByRefUnsafe ( const dtPolyRef ref,
const dtMeshTile** tile,
const dtPoly** poly
)

 Returns the tile and polygon for the specified polygon reference.
Public function Const const dtMeshTile *

getTileAt ( const int x,
const int y,
const int layer
)

 Gets the tile at the specified grid location.
Public function Const const dtMeshTile *

getTileByRef ( dtTileRef ref
)

 Gets the tile for the specified tile reference.
Public function Const int

getTileCountAt ( const int x,
const int y
)

 BEGIN Gets number of tiles at the specified grid location. (All layers.)
Public function Const unsigned int

getTileIndex ( const dtMeshTile* tile
)

  
Public function Const dtTileRef

getTileRef ( const dtMeshTile* tile
)

 Gets the tile reference for the specified tile.
Public function Const dtTileRef

getTileRefAt ( int x,
int y,
int layer
)

 Gets the tile reference for the tile at specified grid location.
Public function Const int

getTilesAt ( const int x,
const int y,
dtMeshTile const** tiles,
const int maxTiles
)

 Gets all tiles at the specified grid location.
Public function Const int

getTileStateSize ( const dtMeshTile* tile
)

 Gets the size of the buffer required by storeTileState to store the specified tile's state.
Public function Const dtReal  
Public function Const dtReal  
Public function Const dtReal  
Public function dtStatus

init ( const dtNavMeshParams* params
)

 Initializes the navigation mesh for tiled use.
Public function dtStatus

init ( unsigned char* data,
const int dataSize,
const int flags
)

 Initializes the navigation mesh for single tile use.
Public function Const bool

isEmpty ()

  
Public function Const bool

isTileLocInValidRange ( const dtReal* pos
)

 Calculates whether the tile grid location for the specified world position can fit in the tile indices type (currently an int)
Public function Const bool

isValidPolyRef ( dtPolyRef ref
)

 Checks the validity of a polygon reference.
Public function void

linkOffMeshHelper ( dtMeshTile* tile0,
unsigned int polyIdx0,
dtMeshTile* tile1,
unsigned int polyIdx1,
unsigned char side,
unsigned char edge
)

 Helper for creating links in off-mesh connections.
Public function dtStatus

removeTile ( dtTileRef ref,
unsigned char** data,
int* dataSize
)

 Removes the specified tile from the navigation mesh.
Public function dtStatus

restoreTileState ( dtMeshTile* tile,
const unsigned char* data,
const int maxDataSize
)

 Restores the state of the tile.
Public function dtStatus

setPolyArea ( dtPolyRef ref,
unsigned char area
)

 Sets the user defined area for the specified polygon.
Public function dtStatus

setPolyFlags ( dtPolyRef ref,
unsigned short flags
)

 Sets the user defined flags for the specified polygon.
Public function Const dtStatus

storeTileState ( const dtMeshTile* tile,
unsigned char* data,
const int maxDataSize
)

 Stores the non-structural state of the tile in the specified buffer.
Public function void

updateOffMeshConnectionByUserId ( unsigned long long int userId,
unsigned char newArea,
unsigned short newFlags
)

 Updates area and flags for specified off-mesh connection: point type

See Also

dtNavMeshQuery

dtCreateNavMeshData

dtNavMeshCreateParams

dtAllocNavMesh

dtFreeNavMesh

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