Struct PerTerrainLayerModification

int layer

Unity terrain layer that this modification applies to.

RecastNavmeshModifier.Mode mode

Surface rasterization mode.

int surfaceID

Voxel area for mesh.

This area (not to be confused with pathfinding areas, this is only used when rasterizing meshes for the recast graph) field can be used to explicitly insert edges in the navmesh geometry or to make some parts of the mesh unwalkable.

When rasterizing the world and two objects with different surface id values are adjacent to each other, a split in the navmesh geometry will be added between them, characters will still be able to walk between them, but this can be useful when working with navmesh updates.

Navmesh updates which recalculate a whole tile (updatePhysics=True) are very slow So if there are special places which you know are going to be updated quite often, for example at a door opening (opened/closed door) you can use surface IDs to create splits on the navmesh for easier updating using normal graph updates (updatePhysics=False). See the below video for more information.

When mode is set to Mode.WalkableSurfaceWithTag then this value will be interpreted as a pathfinding tag. See Working with tags.

float threshold

Threshold for which alpha the terrain layer needs to have for this rule to be applied.

In transitions between textures, the most applicable rule will be used. Given a layer alpha of A, and a threshold of T, the rule with the highest value of A - T will be used.

If there's no rule for a given terrain layer, it is treated as having a threshold of 0.5.

PerTerrainLayerModification Default