Function random_walkable 

pub fn random_walkable<R: Rng>(
    walkmap: &[bool],
    width: usize,
    _height: usize,
    rng: &mut R,
) -> Option<(usize, usize)>

Returns a random walkable grid cell, or None if none exist.

Uniformly samples from all walkable cells.

Example

use rustsim_pathfinding::walkability::random_walkable;
use rand::rngs::StdRng;
use rand::SeedableRng;

let walkmap = vec![true; 25];
let mut rng = StdRng::seed_from_u64(42);
let pos = random_walkable(&walkmap, 5, 5, &mut rng);
assert!(pos.is_some());