Mirrored_Repos/veloren
1
0
Fork 0
mirror of https://gitlab.com/veloren/veloren.git synced 2024-08-30 18:12:32 +00:00
Code Issues Packages Projects Releases Wiki Activity

Drastically faster diffuse

Browse Source
This commit is contained in:
Acrimon 2019-09-21 17:40:27 +00:00 committed by Imbris
parent abae438bbc
commit 7647e54858
1 changed files with 5 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
world/src/util/seed_expan.rs
View File

@ -13,18 +13,14 @@ fn cast_u32x8_u8x32(a: [u32; 8]) -> [u8; 32] {
}
/// Simple non-cryptographic diffusion function.
pub fn diffuse(mut x: u32) -> u32 {
x = x.wrapping_add(0x7ed55d16).wrapping_add(x << 12);
x = (x ^ 0xc761c23c) ^ (x >> 19);
x = x.wrapping_add(0x165667b1).wrapping_add(x << 5);
x = x.wrapping_add(0xd3a2646c) ^ (x << 9);
x = x.wrapping_add(0xfd7046c5).wrapping_add(x << 3);
x = (x ^ 0xb55a4f09) ^ (x >> 16);
x = x.wrapping_add((1 << 31) - 13) ^ (x << 13);
x
#[inline(always)]
pub fn diffuse(mut a: u32) -> u32 {
a ^= a.rotate_right(23);
a.wrapping_mul(2654435761)
}
/// Diffuse but takes multiple values as input.
#[inline(always)]
pub fn diffuse_mult(v: &[u32]) -> u32 {
let mut state = (1 << 31) - 1;
for e in v {