timers

src/lib.rs

@@ -2,6 +2,7 @@ pub mod bvh;
 pub mod map;
 pub mod aabb;
 pub mod model;
+pub mod timer;
 pub mod zeroes;
 pub mod integer;
 pub mod updatable;

src/timer.rs

@@ -0,0 +1,292 @@
+use crate::integer::{Time,Ratio64};
+
+#[derive(Clone,Copy,Debug)]
+pub struct Paused;
+#[derive(Clone,Copy,Debug)]
+pub struct Unpaused;
+
+pub trait PauseState:Copy+std::fmt::Debug{
+	const IS_PAUSED:bool;
+	fn new()->Self;
+}
+impl PauseState for Paused{
+	const IS_PAUSED:bool=true;
+	fn new()->Self{
+		Self
+	}
+}
+impl PauseState for Unpaused{
+	const IS_PAUSED:bool=false;
+	fn new()->Self{
+		Self
+	}
+}
+
+#[derive(Clone,Copy,Debug)]
+pub struct Realtime{
+	offset:Time,
+}
+impl Realtime{
+	const fn new(offset:Time)->Self{
+		Self{offset}
+	}
+}
+
+#[derive(Clone,Copy,Debug)]
+pub struct Scaled{
+	scale:Ratio64,
+	offset:Time,
+}
+impl Scaled{
+	const fn new(scale:Ratio64,offset:Time)->Self{
+		Self{scale,offset}
+	}
+	const fn with_scale(scale:Ratio64)->Self{
+		Self{scale,offset:Time::ZERO}
+	}
+	const fn scale(&self,time:Time)->Time{
+		Time::raw(self.scale.mul_int(time.get()))
+	}
+	const fn get_scale(&self)->Ratio64{
+		self.scale
+	}
+	fn set_scale(&mut self,time:Time,new_scale:Ratio64){
+		let new_time=self.get_time(time);
+		self.scale=new_scale;
+		self.set_time(time,new_time);
+	}
+}
+
+pub trait TimerState:Copy+std::fmt::Debug{
+	fn identity()->Self;
+	fn get_time(&self,time:Time)->Time;
+	fn set_time(&mut self,time:Time,new_time:Time);
+	fn get_offset(&self)->Time;
+	fn set_offset(&mut self,offset:Time);
+}
+impl TimerState for Realtime{
+	fn identity()->Self{
+		Self{offset:Time::ZERO}
+	}
+	fn get_time(&self,time:Time)->Time{
+		time+self.offset
+	}
+	fn set_time(&mut self,time:Time,new_time:Time){
+		self.offset=new_time-time;
+	}
+	fn get_offset(&self)->Time{
+		self.offset
+	}
+	fn set_offset(&mut self,offset:Time){
+		self.offset=offset;
+	}
+}
+impl TimerState for Scaled{
+	fn identity()->Self{
+		Self{scale:Ratio64::ONE,offset:Time::ZERO}
+	}
+	fn get_time(&self,time:Time)->Time{
+		self.scale(time)+self.offset
+	}
+	fn set_time(&mut self,time:Time,new_time:Time){
+		self.offset=new_time-self.scale(time);
+	}
+	fn get_offset(&self)->Time{
+		self.offset
+	}
+	fn set_offset(&mut self,offset:Time){
+		self.offset=offset;
+	}
+}
+
+#[derive(Clone,Copy,Debug)]
+pub struct TimerFixed<T:TimerState,P:PauseState>{
+	state:T,
+	_paused:P,
+}
+
+//scaled timer methods are generic across PauseState
+impl<P:PauseState> TimerFixed<Scaled,P>{
+	pub fn scaled(time:Time,new_time:Time,scale:Ratio64)->Self{
+		let mut timer=Self{
+			state:Scaled::with_scale(scale),
+			_paused:P::new(),
+		};
+		timer.set_time(time,new_time);
+		timer
+	}
+	pub const fn get_scale(&self)->Ratio64{
+		self.state.get_scale()
+	}
+	pub fn set_scale(&mut self,time:Time,new_scale:Ratio64){
+		self.state.set_scale(time,new_scale)
+	}
+}
+
+//pause and unpause is generic across TimerState
+impl<T:TimerState> TimerFixed<T,Paused>{
+	pub fn into_unpaused(self,time:Time)->TimerFixed<T,Unpaused>{
+		let new_time=self.time(time);
+		let mut timer=TimerFixed{
+			state:self.state,
+			_paused:Unpaused,
+		};
+		timer.set_time(time,new_time);
+		timer
+	}
+}
+impl<T:TimerState> TimerFixed<T,Unpaused>{
+	pub fn into_paused(self,time:Time)->TimerFixed<T,Paused>{
+		let new_time=self.time(time);
+		let mut timer=TimerFixed{
+			state:self.state,
+			_paused:Paused,
+		};
+		timer.set_time(time,new_time);
+		timer
+	}
+}
+
+//the new constructor and time queries are generic across both
+impl<T:TimerState,P:PauseState> TimerFixed<T,P>{
+	pub fn new(time:Time,new_time:Time)->Self{
+		let mut timer=Self{
+			state:T::identity(),
+			_paused:P::new(),
+		};
+		timer.set_time(time,new_time);
+		timer
+	}
+	pub fn from_state(state:T)->Self{
+		Self{
+			state,
+			_paused:P::new(),
+		}
+	}
+	pub fn into_state(self)->T{
+		self.state
+	}
+	pub fn time(&self,time:Time)->Time{
+		match P::IS_PAUSED{
+			true=>self.state.get_offset(),
+			false=>self.state.get_time(time),
+		}
+	}
+	pub fn set_time(&mut self,time:Time,new_time:Time){
+		match P::IS_PAUSED{
+			true=>self.state.set_offset(new_time),
+			false=>self.state.set_time(time,new_time),
+		}
+	}
+}
+
+#[derive(Debug)]
+pub enum Error{
+	AlreadyPaused,
+	AlreadyUnpaused,
+}
+impl std::fmt::Display for Error{
+	fn fmt(&self,f:&mut std::fmt::Formatter<'_>)->std::fmt::Result{
+		write!(f,"{self:?}")
+	}
+}
+impl std::error::Error for Error{}
+
+//wrapper type which holds type state internally
+#[derive(Clone,Debug)]
+pub enum Timer<T:TimerState>{
+	Paused(TimerFixed<T,Paused>),
+	Unpaused(TimerFixed<T,Unpaused>),
+}
+impl<T:TimerState> Timer<T>{
+	pub fn from_state(state:T,paused:bool)->Self{
+		match paused{
+			true=>Self::Paused(TimerFixed::from_state(state)),
+			false=>Self::Unpaused(TimerFixed::from_state(state)),
+		}
+	}
+	pub fn into_state(self)->(T,bool){
+		match self{
+			Self::Paused(timer)=>(timer.into_state(),true),
+			Self::Unpaused(timer)=>(timer.into_state(),false),
+		}
+	}
+	pub fn paused(time:Time,new_time:Time)->Self{
+		Self::Paused(TimerFixed::new(time,new_time))
+	}
+	pub fn unpaused(time:Time,new_time:Time)->Self{
+		Self::Unpaused(TimerFixed::new(time,new_time))
+	}
+	pub fn time(&self,time:Time)->Time{
+		match self{
+			Self::Paused(timer)=>timer.time(time),
+			Self::Unpaused(timer)=>timer.time(time),
+		}
+	}
+	pub fn set_time(&mut self,time:Time,new_time:Time){
+		match self{
+			Self::Paused(timer)=>timer.set_time(time,new_time),
+			Self::Unpaused(timer)=>timer.set_time(time,new_time),
+		}
+	}
+	pub fn pause(&mut self,time:Time)->Result<(),Error>{
+		*self=match *self{
+			Self::Paused(_)=>return Err(Error::AlreadyPaused),
+			Self::Unpaused(timer)=>Self::Paused(timer.into_paused(time)),
+		};
+		Ok(())
+	}
+	pub fn unpause(&mut self,time:Time)->Result<(),Error>{
+		*self=match *self{
+			Self::Paused(timer)=>Self::Unpaused(timer.into_unpaused(time)),
+			Self::Unpaused(_)=>return Err(Error::AlreadyUnpaused),
+		};
+		Ok(())
+	}
+}
+
+#[cfg(test)]
+mod test{
+	use super::{Time,Timer,TimerFixed,Error,Realtime,Scaled,Paused};
+	macro_rules! sec {
+		($s: expr) => {
+			Time::from_secs($s)
+		};
+	}
+	#[test]
+	fn test_timerfixed_scaled(){
+		//create a paused timer that reads 0s
+		let timer=TimerFixed::<Scaled,Paused>::new(sec!(0),sec!(0));
+		//the paused timer at 1 second should read 0s
+		assert_eq!(timer.time(sec!(1)),sec!(0));
+
+		//unpause it after one second
+		let timer=timer.into_unpaused(sec!(1));
+		//the timer at 6 seconds should read 5s
+		assert_eq!(timer.time(sec!(6)),sec!(5));
+
+		//pause the timer after 11 seconds
+		let timer=timer.into_paused(sec!(11));
+		//the paused timer at 20 seconds should read 10s
+		assert_eq!(timer.time(sec!(20)),sec!(10));
+	}
+	#[test]
+	fn test_timer()->Result<(),Error>{
+		//create a paused timer that reads 0s
+		let mut timer=Timer::<Realtime>::paused(sec!(0),sec!(0));
+		//the paused timer at 1 second should read 0s
+		assert_eq!(timer.time(sec!(1)),sec!(0));
+
+		//unpause it after one second
+		timer.unpause(sec!(1))?;
+		//the timer at 6 seconds should read 5s
+		assert_eq!(timer.time(sec!(6)),sec!(5));
+
+		//pause the timer after 11 seconds
+		timer.pause(sec!(11))?;
+		//the paused timer at 20 seconds should read 10s
+		assert_eq!(timer.time(sec!(20)),sec!(10));
+
+		Ok(())
+	}
+}