46 lines
1005 B
Rust
46 lines
1005 B
Rust
use crate::math::Vec3;
|
|
use crate::realtype::NormalizedToU32;
|
|
|
|
fn spread_bits(v: u32) -> u32 {
|
|
let mut result = 0;
|
|
for power in 0..9 {
|
|
result |= ((1 << power) & v) << (power * 2);
|
|
}
|
|
result
|
|
}
|
|
|
|
pub fn morton_order_value_3d(p: Vec3<f64>) -> u32 {
|
|
let x = p.x().normalized_to_u32(10);
|
|
let y = p.y().normalized_to_u32(10);
|
|
let z = p.z().normalized_to_u32(10);
|
|
(spread_bits(x) << 2) | (spread_bits(y) << 1) | spread_bits(z)
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod tests {
|
|
use super::*;
|
|
mod spread_bits {
|
|
use super::*;
|
|
|
|
#[test]
|
|
fn zero_yields_zero() {
|
|
assert!(spread_bits(0) == 0);
|
|
}
|
|
|
|
#[test]
|
|
fn one_yields_one() {
|
|
assert!(spread_bits(1) == 1);
|
|
}
|
|
|
|
#[test]
|
|
fn b1111_yields_b1001001001() {
|
|
assert!(spread_bits(0b1111) == 0b1001001001);
|
|
}
|
|
|
|
#[test]
|
|
fn b1010_yields_b1000001000() {
|
|
assert!(spread_bits(0b1010) == 0b1000001000);
|
|
}
|
|
}
|
|
}
|