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use super::*; #[doc(no_inline)] pub use rand::distributions::Distribution; #[doc(no_inline)] pub use rand::seq::{IteratorRandom as _, SliceRandom as _}; #[doc(no_inline)] pub use rand::{self, rngs::StdRng, Rng, RngCore, SeedableRng}; pub mod distributions { use super::*; #[doc(no_inline)] pub use rand::distributions::*; pub struct UnitCircleInside; impl Distribution<Vec2<f32>> for UnitCircleInside { fn sample<R: Rng + ?Sized>(&self, rng: &mut R) -> Vec2<f32> { let r = rng.gen_range(0.0, 1.0).sqrt(); let a = rng.gen_range(0.0, 2.0 * std::f32::consts::PI); vec2(r * a.sin(), r * a.cos()) } } } pub fn global_rng() -> impl Rng { #[cfg(target_arch = "wasm32")] { static GLOBAL_RNG: once_cell::sync::Lazy<Mutex<StdRng>> = once_cell::sync::Lazy::new(|| { fn gen_byte() -> u8 { clamp(js_sys::Math::random() * 256.0, 0.0..=255.0) as u8 } let mut seed: [mem::MaybeUninit<u8>; 32] = unsafe { mem::MaybeUninit::uninit().assume_init() }; for elem in &mut seed { unsafe { std::ptr::write(elem.as_mut_ptr(), gen_byte()); } } Mutex::new(rand::SeedableRng::from_seed(unsafe { mem::transmute(seed) })) }); struct GlobalRng; impl RngCore for GlobalRng { fn next_u32(&mut self) -> u32 { GLOBAL_RNG.lock().unwrap().next_u32() } fn next_u64(&mut self) -> u64 { GLOBAL_RNG.lock().unwrap().next_u64() } fn fill_bytes(&mut self, dest: &mut [u8]) { GLOBAL_RNG.lock().unwrap().fill_bytes(dest); } fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), rand::Error> { GLOBAL_RNG.lock().unwrap().try_fill_bytes(dest) } } GlobalRng } #[cfg(not(target_arch = "wasm32"))] rand::thread_rng() } #[test] fn test_random() { macro_rules! test_types { ($($t:ty,)*) => { $(eprintln!("random {:?} = {:?}", stringify!($t), global_rng().gen::<$t>());)* }; } test_types!(i8, i16, i32, i64, isize, u8, u16, u32, u64, usize, char, f32, f64,); }