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#![allow(dead_code)]
use std::ops::{Add, Sub, Mul, Div};
pub mod tuning;
#[derive(Debug, Clone, Copy, PartialEq)]
pub struct Hz(pub f32);
impl Add<Cents> for Hz {
type Output = Hz;
fn add(self, rhs: Cents) -> Self::Output {
let freq = self.0 * (rhs.0 / 1200.0).exp2();
Hz(freq)
}
}
impl Sub<Cents> for Hz {
type Output = Hz;
fn sub(self, rhs: Cents) -> Self::Output {
let freq = self.0 * (-rhs.0 / 1200.0).exp2();
Hz(freq)
}
}
impl Mul<f32> for Hz {
type Output = Hz;
fn mul(self, rhs: f32) -> Self::Output {
Hz(self.0 * rhs)
}
}
impl Div<Hz> for Hz {
type Output = Cents;
fn div(self, rhs: Hz) -> Self::Output {
Cents::from_ratio(self.0 / rhs.0)
}
}
#[derive(Debug, Clone, Copy, PartialEq)]
pub struct Cents(pub f32);
impl Cents {
pub fn from_ratio(ratio: f32) -> Cents {
Cents(1200.0 * ratio.log2())
}
}
impl Add<Cents> for Cents {
type Output = Cents;
fn add(self, rhs: Cents) -> Self::Output {
Cents(self.0 + rhs.0)
}
}
impl Sub<Cents> for Cents {
type Output = Cents;
fn sub(self, rhs: Cents) -> Self::Output {
Cents(self.0 - rhs.0)
}
}
impl Mul<f32> for Cents {
type Output = Cents;
fn mul(self, rhs: f32) -> Self::Output {
Cents(self.0 * rhs)
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test] fn cents_ratio() {
assert_eq!(
Cents::from_ratio(2.0),
Cents(1200.0)
);
}
#[test] fn hz_plus_cents() {
assert_eq!(
(Hz(440.0) + Cents(-900.0)).0.round(),
262.0
);
}
#[test] fn hz_div_hz() {
assert_eq!(
Hz(660.0) / Hz(440.0),
Cents::from_ratio(3.0 / 2.0)
);
}
}