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dtNavMesh

A navigation mesh based on tiles of convex polygons.

API > API/Runtime > API/Runtime/Navmesh

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.
   
Name dtNavMesh
Type class
Header File /Engine/Source/Runtime/Navmesh/Public/Detour/DetourNavMesh.h
Include Path #include "Detour/DetourNavMesh.h"

Syntax

class dtNavMesh

Constructors

Name Remarks Include Path Unreal Specifiers

dtNavMesh()

   Detour/DetourNavMesh.h  

Destructors

Name Remarks Include Path Unreal Specifiers

~dtNavMesh()

   Detour/DetourNavMesh.h  

Structs

Name Remarks
FConnectingPolyData [UE] result struct for findConnectingPolys

Variables

Public

Name Type Remarks Include Path Unreal Specifiers
m_areaCostOrder unsigned char   Detour/DetourNavMesh.h  
m_maxTiles int Max number of tiles. Detour/DetourNavMesh.h  
m_nextFree dtMeshTile * Freelist of tiles. Detour/DetourNavMesh.h  
m_orig dtReal Origin of the tile (0,0) Detour/DetourNavMesh.h  
m_params dtNavMeshParams Current initialization params. Detour/DetourNavMesh.h  
m_polyBits unsigned int Number of poly bits in the tile ID. Detour/DetourNavMesh.h  
m_posLookup dtMeshTile ** Tile hash lookup. Detour/DetourNavMesh.h  
m_saltBits unsigned int Number of salt bits in the tile ID. Detour/DetourNavMesh.h  
m_tileBits unsigned int Number of tile bits in the tile ID. Detour/DetourNavMesh.h  
m_tileHeight dtReal Dimensions of each tile. Detour/DetourNavMesh.h  
m_tileLutMask int Tile hash lookup mask. Detour/DetourNavMesh.h  
m_tileLutSize int Tile hash lookup size (must be pot). Detour/DetourNavMesh.h  
m_tiles dtMeshTile * List of tiles. Detour/DetourNavMesh.h  
m_tileWidth dtReal   Detour/DetourNavMesh.h  

Functions

Public

Name Remarks Include Path Unreal Specifiers

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

 Adds a tile to the navigation mesh. Detour/DetourNavMesh.h  

void applyAreaCostOrder ( unsigned char* costOrder
)

   Detour/DetourNavMesh.h  

void applyWorldOffset ( const dtReal* offset
)

 Shift navigation mesh by provided offset. Detour/DetourNavMesh.h  

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

 Calculates the tile grid location for the specified world position. Detour/DetourNavMesh.h  

unsigned int decodeClusterIdTile ( dtClusterRef ref
) const

 Extracts the tile's index from the specified cluster reference. Detour/DetourNavMesh.h  

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

 Decodes a standard polygon reference. This function is generally meant for internal use only. Detour/DetourNavMesh.h  

unsigned int decodePolyIdPoly ( dtPolyRef ref
) const

 Extracts the polygon's index (within its tile) from the specified polygon reference. Detour/DetourNavMesh.h  

unsigned int decodePolyIdSalt ( dtPolyRef ref
) const

 Extracts a tile's salt value from the specified polygon reference. Detour/DetourNavMesh.h  

unsigned int decodePolyIdTile ( dtPolyRef ref
) const

 Extracts the tile's index from the specified polygon reference. Detour/DetourNavMesh.h  

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

 Derives a standard polygon reference. This function is generally meant for internal use only. Detour/DetourNavMesh.h  

dtReal getBVQuantFactor ( const unsigned char resolution
) const

   Detour/DetourNavMesh.h  

dtClusterRef getClusterRefBase ( const dtMeshTile* tile
) const

 Gets the cluster reference for the tile's base cluster. Detour/DetourNavMesh.h  

dtLink & getLink ( dtMeshTile* tile,
unsigned int linkIdx
)

 Helper for accessing links. Detour/DetourNavMesh.h  

const dtLink & getLink ( const dtMeshTile* tile,
unsigned int linkIdx
) const

   Detour/DetourNavMesh.h  

int getMaxTiles()

 The maximum number of tiles supported by the navigation mesh. Detour/DetourNavMesh.h  

dtMeshTile * getMutableTileByRef ( dtTileRef ref
) const

 Gets the tile for the specified tile reference. Detour/DetourNavMesh.h  

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

   Detour/DetourNavMesh.h  

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

 Returns neighbour tile count based on side of given tile. Detour/DetourNavMesh.h  

const dtOffMeshConnection * getOffMeshConnectionByRef ( dtPolyRef ref
) const

 Gets the specified off-mesh connection: point type. Detour/DetourNavMesh.h  

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

 Gets the endpoints for an off-mesh connection, ordered by "direction of travel". Detour/DetourNavMesh.h  
The navigation mesh initialization params. Detour/DetourNavMesh.h  

dtStatus getPolyArea ( dtPolyRef ref,
unsigned char* resultArea
) const

 Gets the user defined area for the specified polygon. Detour/DetourNavMesh.h  

dtStatus getPolyFlags ( dtPolyRef ref,
unsigned short* resultFlags
) const

 Gets the user defined flags for the specified polygon. Detour/DetourNavMesh.h  

dtPolyRef getPolyRefBase ( const dtMeshTile* tile
) const

 Gets the polygon reference for the tile's base polygon. Detour/DetourNavMesh.h  

unsigned int getSaltBits()

   Detour/DetourNavMesh.h  

const dtMeshTile * getTile ( int i
) const

 Gets the tile at the specified index. Detour/DetourNavMesh.h  

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

 Gets the tile and polygon for the specified polygon reference. Detour/DetourNavMesh.h  

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

 Returns the tile and polygon for the specified polygon reference. Detour/DetourNavMesh.h  

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

 Gets the tile at the specified grid location. Detour/DetourNavMesh.h  

const dtMeshTile * getTileByRef ( dtTileRef ref
) const

 Gets the tile for the specified tile reference. Detour/DetourNavMesh.h  

int getTileCountAt ( const int x,
const int y
) const

 @UE BEGIN Gets number of tiles at the specified grid location. (All layers.) Detour/DetourNavMesh.h  

unsigned int getTileIndex ( const dtMeshTile* tile
) const

   Detour/DetourNavMesh.h  

dtTileRef getTileRef ( const dtMeshTile* tile
) const

 Gets the tile reference for the specified tile. Detour/DetourNavMesh.h  

dtTileRef getTileRefAt ( int x,
int y,
int layer
) const

 Gets the tile reference for the tile at specified grid location. Detour/DetourNavMesh.h  

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

 Gets all tiles at the specified grid location. Detour/DetourNavMesh.h  

int getTileStateSize ( const dtMeshTile* tile
) const

 Gets the size of the buffer required by storeTileState to store the specified tile's state. Detour/DetourNavMesh.h  

dtReal getWalkableClimb()

   Detour/DetourNavMesh.h  

dtReal getWalkableHeight()

   Detour/DetourNavMesh.h  

dtReal getWalkableRadius()

   Detour/DetourNavMesh.h  

dtStatus init ( const dtNavMeshParams* params
)

 Initializes the navigation mesh for tiled use. Detour/DetourNavMesh.h  

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

 Initializes the navigation mesh for single tile use. Detour/DetourNavMesh.h  

bool isEmpty()

   Detour/DetourNavMesh.h  

bool isTileLocInValidRange ( const dtReal* pos
) const

 Calculates whether the tile grid location for the specified world position can fit in the tile indices type (currently an int) Detour/DetourNavMesh.h  

bool isValidPolyRef ( dtPolyRef ref
) const

 Checks the validity of a polygon reference. Detour/DetourNavMesh.h  

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

 Helper for creating links in off-mesh connections. Detour/DetourNavMesh.h  

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

 Removes the specified tile from the navigation mesh. Detour/DetourNavMesh.h  

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

 Restores the state of the tile. Detour/DetourNavMesh.h  

dtStatus setPolyArea ( dtPolyRef ref,
unsigned char area
)

 Sets the user defined area for the specified polygon. Detour/DetourNavMesh.h  

dtStatus setPolyFlags ( dtPolyRef ref,
unsigned short flags
)

 Sets the user defined flags for the specified polygon. Detour/DetourNavMesh.h  

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

 Stores the non-structural state of the tile in the specified buffer. Detour/DetourNavMesh.h  

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

 Updates area and flags for specified off-mesh connection: point type Detour/DetourNavMesh.h  

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