Module spatial 

Structs

SpatialGrid

In-memory spatial grid mapping cell coordinates to entity ID lists.

SpatialHashGrid

Dense spatial grid for O(1) entity lookup by position. Grid cells are cell_size x cell_size world units. Uses u64 entity handles — zero-copy, no per-entity String allocation.

Constants

CELL_SIZE

Cell size in world units.

Functions

action_horizon_cells

Return 3x3 neighbor cell coordinates for AOI queries.

astar

Bounded A* pathfinding. Returns path as Vec<(i32, i32)> excluding start. cost_fn returns movement cost (999 = impassable) for a given (x, y). Bounded by max_steps to prevent unbounded work.

cell_coord

Compute cell coordinate from world position (floor division).

compute_cell_id

Compute deterministic cell ID from world/region/position.

compute_fov

Compute field-of-view positions from (ox, oy) with given radius. Uses 8-octant recursive shadowcasting.

compute_observer_visibility_mask

Compute observer visibility mask: 1 for visible meshlets, 0 for culled. fov_cells is the output of compute_fov. meshlet_coords are the (x, y) cell positions of each meshlet.

distance_squared

Compute squared distance between two points. Integer-only, no sqrt.

fill_observer_visibility_mask

Zero-allocation version: writes into caller-provided output slice. out must be at least meshlet_coords.len() long.