use std::time::Duration;
pub trait SignalU8: Sized {
fn eval(&self, after: Duration) -> u8;
fn min(self, min: u8) -> Min<Self> {
Min { signal: self, min }
}
}
pub struct Linear {
duration: Duration,
}
impl Linear {
pub fn with_duration(duration: Duration) -> Self {
Self { duration }
}
pub fn with_step_duration(step_duration: Duration) -> Self {
Self::with_duration(step_duration * 255)
}
}
impl SignalU8 for Linear {
fn eval(&self, after: Duration) -> u8 {
if after >= self.duration {
255
} else {
(after.as_millis() * 255u128 / self.duration.as_millis()) as u8
}
}
}
pub struct SquareWave01 {
half_period: Duration,
}
impl SquareWave01 {
pub fn with_half_period(half_period: Duration) -> Self {
Self { half_period }
}
pub fn eval_bool(&self, after: Duration) -> bool {
(after.as_millis() / self.half_period.as_millis()).is_multiple_of(2)
}
}
impl SignalU8 for SquareWave01 {
fn eval(&self, after: Duration) -> u8 {
self.eval_bool(after) as u8
}
}
pub struct Min<S: SignalU8> {
pub signal: S,
pub min: u8,
}
impl<S: SignalU8> SignalU8 for Min<S> {
fn eval(&self, after: Duration) -> u8 {
self.signal.eval(after).min(self.min)
}
}
pub struct SmoothSquareWave {
constant: Duration,
transition: Duration,
}
impl SmoothSquareWave {
pub fn new(constant: Duration, transition: Duration) -> Self {
Self {
constant,
transition,
}
}
}
impl SignalU8 for SmoothSquareWave {
fn eval(&self, after: Duration) -> u8 {
let constant = self.constant.as_millis();
let transition = self.transition.as_millis();
let mut remain_within_cycle = after.as_millis() % (2 * (constant + transition));
if remain_within_cycle < constant {
return 0;
}
remain_within_cycle -= constant;
if remain_within_cycle < transition {
return ((remain_within_cycle * 255) / transition) as u8;
}
remain_within_cycle -= transition;
if remain_within_cycle < constant {
return 255;
}
remain_within_cycle -= constant;
255 - ((remain_within_cycle * 255) / transition) as u8
}
}