Struct Rng 

pub struct Rng { /* private fields */ }

Lightweight seeded pseudo-random number generator (xoshiro256**). Used throughout procedural generation for reproducibility.

Implementations

impl Rng

pub fn new(seed: u64) -> Self

pub fn next_u64(&mut self) -> u64

Next u64 (xoshiro256**).

pub fn next_f32(&mut self) -> f32

Next f32 in [0, 1).

pub fn range_f32(&mut self, min: f32, max: f32) -> f32

Next f32 in [min, max).

pub fn range_usize(&mut self, n: usize) -> usize

Next usize in [0, n).

pub fn range_i32(&mut self, min: i32, max: i32) -> i32

Next i32 in [min, max].

pub fn chance(&mut self, p: f32) -> bool

Bernoulli: true with probability p ∈ [0, 1].

pub fn shuffle<T>(&mut self, slice: &mut [T])

Shuffle a slice in-place (Fisher-Yates).

pub fn pick<'a, T>(&mut self, slice: &'a [T]) -> Option<&'a T>

Pick a random element from a slice.

pub fn pick_weighted<'a, T>(&mut self, items: &'a [(T, f32)]) -> Option<&'a T>

Pick a random element from a weighted list. Weights can be any positive f32.

pub fn gaussian(&mut self, mean: f32, stddev: f32) -> f32

Gaussian sample with given mean and stddev (Box-Muller).

pub fn poisson(&mut self, lambda: f32) -> u32

Poisson-distributed random integer with given lambda.

pub fn fork(&mut self) -> Rng

Fork: create a child RNG seeded from this one (deterministic).

Trait Implementations

impl Clone for Rng

fn clone(&self) -> Rng

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Rng

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.