Data Structures

HexaPattern

Enum defining the grid placement type.

Name	Description
SQUARE	Regular square grid
HEXAGONE	Flat-top hexagonal grid with axial coordinates (q, r)

ZPositionCalculate

Enum defining the algorithm for computing a mesh’s Z position.

Name	Description
SINGLE_POINT	Z computed at the mesh center only
FOUR_POINT	Z = minimum of the 4 bounding box corners (rotation taken into account)
HEIGHT_POINT	Z = minimum of 8 points (4 corners + 4 edge midpoints)

FCMeshStruct

Configuration structure for an individual mesh (DataTable row).

Name	Description
description	Text description of the mesh
mesh	Reference to the `UStaticMesh`
zAlgo	Z calculation algorithm (`ZPositionCalculate`)
percentBelowFloor	Percentage of the mesh sunk below ground (default 10.0)

// FCMeshStruct is configured in a DataTable.
// Each row represents a mesh with its Z positioning algorithm.

FCMeshStruct meshStruct;
meshStruct.mesh = myStaticMesh;
meshStruct.zAlgo = ZPositionCalculate::FOUR_POINT;
meshStruct.percentBelowFloor = 15.0; // 15% of the bounding box below ground

FCMeshProbaStruct

Probabilistic mesh selection structure.

Name	Description
meshProbaRHArray	`FDataTableRowHandle` pointing to a `FCMeshStruct` row
meshSelectLowerBound	Selection lower bound (default 0.0)
meshSelectUpperBound	Selection upper bound (default 2.0)

// Selection works as follows:
// A random [0.0, 1.0] is drawn per tile.
// The first FCMeshProbaStruct whose [lowerBound, upperBound] contains the value is selected.

// Example: 3 meshes with probabilities 60%, 30%, 10%
FCMeshProbaStruct tree;   // lowerBound=0.0, upperBound=0.6
FCMeshProbaStruct rock;   // lowerBound=0.6, upperBound=0.9
FCMeshProbaStruct bush;   // lowerBound=0.9, upperBound=1.0

FCHexaMakerStruct

Main configuration structure for a placement layer (DataTable row). Each layer is independent and has its own parameters.

Name	Description
description	Text description of the layer
enable	Enables/disables this layer
biomeSelectLowerBound	Biome noise filter lower bound
biomeSelectUpperBound	Biome noise filter upper bound (0=0 disables the filter)
onlyForRoomTag	Allowed room tags (empty = all)
meshProbaRHArray	Array of `FCMeshProbaStruct` for probabilistic selection
shadowBehavior	Shadow configuration (`FCShadowDefinition`)
pattern	Grid type: `SQUARE` or `HEXAGONE`
tileSize	Cell size in world units (default 150)
nbHexaAround	Number of cells around the player (generation radius)
alignToSlope	Aligns mesh rotation to terrain slope
rotate	Random Y rotation [0°, 360°]
minJitterForce	Minimum dispersion force (ratio of tileSize)
maxJitterForce	Maximum dispersion force (ratio of tileSize)
minScalePercent	Minimum scale (default 0.5)
maxScalePercent	Maximum scale (default 2.0)
cullDistanceStart	Fade start distance (requires material support)
cullDistanceEnd	Full disappearance distance
withBound	Enables altitude filtering
above	Minimum allowed altitude
below	Maximum allowed altitude
withNormal	Enables slope filtering
zMinNornal	Minimum slope (0=vertical, 0.5=45°, 1=horizontal)
zMaxNornal	Maximum slope
collision	Enables collisions on ISMs
explicitRemove	If true, old ISMs are explicitly unregistered
roomType	Zone type: `UNSET`, `ROOM`, `CORRIDOR`, `WALL`
meshSelectRateDistanceToEdgeLowerBound	Lower bound distance to corridor edge (if CORRIDOR)
meshSelectRateDistanceToEdgeUpperBound	Upper bound distance to corridor edge (if CORRIDOR)
meshSelectRateDistanceToRoomLowerBound	Lower bound distance to room center (if ROOM)
meshSelectRateDistanceToRoomUpperBound	Upper bound distance to room center (if ROOM)

// FCHexaMakerStruct is configured in a DataTable.
// Each row represents an independent placement "layer".

FCHexaMakerStruct layer;
layer.pattern = HexaPattern::HEXAGONE;
layer.tileSize = 200;
layer.nbHexaAround = 8;
layer.rotate = true;
layer.minJitterForce = 0.1;
layer.maxJitterForce = 0.3;
layer.minScalePercent = 0.8;
layer.maxScalePercent = 1.5;
layer.alignToSlope = true;
layer.withBound = true;
layer.above = -500.0;
layer.below = 5000.0;
layer.withNormal = true;
layer.zMinNornal = 0.7;  // no placement on steep slopes
layer.zMaxNornal = 1.0;
layer.cullDistanceStart = 10000;
layer.cullDistanceEnd = 15000;
layer.roomType = CRoomType::ROOM;

FCHexaSpawnerDataStruct

DataTable structure combining multiple placement layers.

Name	Description
hexaMakerRHArray	Array of `FDataTableRowHandle` pointing to `FCHexaMakerStruct` rows

// FCHexaSpawnerDataStruct is referenced by ACHexaSpawner via FDataTableRowHandle.
// It contains the list of layers to generate.
// Each layer is distributed across available CPU cores for parallel computation.

TArray<FCHexaMakerStruct*> layers = data->getHexaMakerStructArray();
// Returns the resolved FCHexaMakerStruct* from the DataTableRowHandles.