fdtd-coremem/crates/coremem/src/driver.rs

use crate::diagnostics::SyncDiagnostics;
use crate::geom::{Coord, Index, Region};
use crate::mat;
use crate::meas::{self, AbstractMeasurement};
use crate::real::Real;
use crate::render::{self, MultiRenderer, Renderer};
use crate::sim::AbstractSim;
use crate::sim::units::{Frame, Time};
use crate::stim::{Stimulus, DynStimuli};
use coremem_cross::compound::list;

use log::{info, trace};
use serde::{Deserialize, Serialize};
use std::path::PathBuf;
use std::sync::Arc;
use std::sync::mpsc::{sync_channel, SyncSender, Receiver};
use std::time::Instant;
use threadpool::ThreadPool;

pub struct Driver<S, Stim=DynStimuli> {
    state: S,
    renderer: Arc<MultiRenderer<S>>,
    // TODO: use Rayon's thread pool?
    render_pool: ThreadPool,
    render_channel: (SyncSender<()>, Receiver<()>),
    measurements: Vec<Arc<dyn AbstractMeasurement<S>>>,
    stimuli: Stim,
    /// simulation end time
    sim_end_time: Option<Frame>,
    diag: SyncDiagnostics,
    last_diag_time: Instant,
}

impl<S: AbstractSim, Stim> Driver<S, Stim> {
    pub fn new_with_stim(mut state: S, stimuli: Stim) -> Self {
        let diag = SyncDiagnostics::new();
        state.use_diagnostics(diag.clone());
        Self {
            state,
            renderer: Arc::new(MultiRenderer::new()),
            render_pool: ThreadPool::new(3),
            render_channel: sync_channel(0),
            measurements: vec![
                Arc::new(meas::Time),
                Arc::new(meas::Meta),
                Arc::new(meas::Energy::world()),
                Arc::new(meas::Power::world()),
            ],
            stimuli,
            sim_end_time: None,
            diag,
            last_diag_time: Instant::now(),
        }
    }

    pub fn add_measurement<Meas: AbstractMeasurement<S> + 'static>(&mut self, m: Meas) {
        self.measurements.push(Arc::new(m));
    }
}

impl<S: AbstractSim> Driver<S, DynStimuli> {
    pub fn new(state: S) -> Self {
        Self::new_with_stim(state, DynStimuli::default())
    }
    pub fn add_stimulus<Stim: Stimulus + 'static>(&mut self, s: Stim) {
        self.stimuli.push(Box::new(s))
    }
}

impl<S: AbstractSim> Driver<S, list::Empty> {
    pub fn new_unboxed_stim(state: S) -> Self {
        Self::new_with_stim(state, list::Empty::default())
    }
}

impl<S: AbstractSim, Stim> Driver<S, Stim> {
    pub fn with_add_stimulus<E>(self, s: E) -> Driver<S, list::Prepended<E, Stim>>
        where Stim: list::Prependable
    {
        Driver {
            state: self.state,
            renderer: self.renderer,
            render_pool: self.render_pool,
            render_channel: self.render_channel,
            measurements: self.measurements,
            stimuli: self.stimuli.prepend(s),
            sim_end_time: self.sim_end_time,
            diag: self.diag,
            last_diag_time: self.last_diag_time,
        }
    }
    pub fn with_stimulus<NewStim>(self, stimuli: NewStim) -> Driver<S, NewStim> {
        Driver {
            state: self.state,
            renderer: self.renderer,
            render_pool: self.render_pool,
            render_channel: self.render_channel,
            measurements: self.measurements,
            stimuli,
            sim_end_time: self.sim_end_time,
            diag: self.diag,
            last_diag_time: self.last_diag_time,
        }
    }
}

impl<S: AbstractSim, Stim> Driver<S, Stim> {
    pub fn fill_region<Reg: Region, M: Into<S::Material> + Clone>(&mut self, region: &Reg, mat: M) {
        self.state.fill_region(region, mat);
    }
    pub fn test_region_filled<Reg: Region, M>(&mut self, region: &Reg, mat: M) -> bool
    where
        M: Into<S::Material> + Clone,
        S::Material: PartialEq
    {
        self.state.test_region_filled(region, mat)
    }

    pub fn size(&self) -> Index {
        self.state.size()
    }
    pub fn timestep(&self) -> f32 {
        self.state.timestep()
    }
    pub fn time(&self) -> f32 {
        self.state.time()
    }

    pub fn add_classical_boundary<C: Coord>(&mut self, thickness: C)
        where S::Material: From<mat::IsomorphicConductor<f32>>
    {
        self.add_classical_boundary_explicit::<f32, _>(thickness)
    }

    /// the CPU code is parameterized over `Real`: you'll need to use this interface to get access
    /// to that, if using a CPU driver. otherwise, use `add_classical_boundary`
    pub fn add_classical_boundary_explicit<R: Real, C: Coord>(&mut self, thickness: C)
        where S::Material: From<mat::IsomorphicConductor<R>>
    {
        let timestep = self.state.timestep();
        self.state.fill_boundary_using(thickness, |boundary_ness| {
            let b = boundary_ness.elem_pow(3.0);
            let cond = b * (0.5 / timestep);

            let iso_cond = cond.x() + cond.y() + cond.z();
            let iso_conductor = mat::IsomorphicConductor::new(iso_cond.cast());
            iso_conductor
        });
    }
}

impl<S: AbstractSim + 'static, Stim> Driver<S, Stim> {
    fn add_renderer<Rend: Renderer<S> + 'static>(
        &mut self, renderer: Rend, name: &str, step_frequency: u64, frame_limit: Option<u64>
    ) {
        info!("render to {} at f={} until f={:?}", name, step_frequency, frame_limit);
        self.renderer.push(renderer, step_frequency, frame_limit);
    }

    pub fn add_y4m_renderer<P: Into<PathBuf>>(&mut self, output: P, step_frequency: u64, frame_limit: Option<u64>) {
        let output = output.into();
        let name = output.to_string_lossy().into_owned();
        self.add_renderer(render::Y4MRenderer::new(output), &*name, step_frequency, frame_limit);
    }

    pub fn add_term_renderer(&mut self, step_frequency: u64, frame_limit: Option<u64>) {
        self.add_renderer(render::ColorTermRenderer, "terminal", step_frequency, frame_limit);
    }

    pub fn add_csv_renderer(&mut self, path: &str, step_frequency: u64, frame_limit: Option<u64>) {
        self.add_renderer(render::CsvRenderer::new(path), path, step_frequency, frame_limit);
    }
}

impl<S: AbstractSim + Serialize + 'static, Stim> Driver<S, Stim> {
    pub fn add_serializer_renderer(&mut self, out_base: &str, step_frequency: u64, frame_limit: Option<u64>) {
        let fmt_str = format!("{out_base}{{step_no}}.bc", out_base=out_base);
        self.add_renderer(render::SerializerRenderer::new_generic(&*fmt_str), &*fmt_str, step_frequency, frame_limit);
    }
}

impl<S, Stim> Driver<S, Stim>
where
    S: AbstractSim + Send + Sync + Serialize + for<'a> Deserialize<'a> + 'static
{
    /// instruct the driver to periodically save the simulation state to the provided path.
    /// also attempts to load an existing state file, returning `true` on success.
    pub fn add_state_file(&mut self, state_file: &str, snapshot_frequency: u64) -> bool {
        let ser = render::SerializerRenderer::new(state_file);
        let loaded = ser.try_load().map(|s| {
            self.state = s.state;
            self.state.use_diagnostics(self.diag.clone());
        }).is_some();
        self.add_renderer(ser, state_file, snapshot_frequency, None);
        loaded
    }
}

impl<S, Stim> Driver<S, Stim>
where
    S: AbstractSim + Clone + Default + Send + 'static,
    Stim: Stimulus,
{
    fn render(&mut self) {
        self.diag.instrument_render_prep(|| {
            let diag_handle = self.diag.clone();
            let their_state = self.state.clone();
            let their_measurements = self.measurements.clone();
            let renderer = self.renderer.clone();
            let sender = self.render_channel.0.clone();
            self.render_pool.execute(move || {
                // unblock the main thread (this limits the number of renders in-flight at any time
                sender.send(()).unwrap();
                trace!("render begin");
                diag_handle.instrument_render_cpu_side(|| {
                    let meas: Vec<&dyn AbstractMeasurement<S>> = their_measurements.iter().map(|m| &**m).collect();
                    renderer.render(&their_state, &*meas, Default::default());
                });
                trace!("render end");
            });
        });
        self.diag.instrument_render_blocked(|| {
            self.render_channel.1.recv().unwrap();
        });
    }
    /// Return the number of steps actually stepped
    fn step_at_most(&mut self, at_most: u32) -> u32 {
        assert!(at_most != 0);
        let start_step = self.state.step_no();

        if self.renderer.any_work_for_frame(start_step) {
            self.render();
        }

        let mut can_step = 1;
        while can_step < at_most && !self.renderer.any_work_for_frame(start_step + can_step as u64) {
            can_step += 1;
        }
        trace!("step begin");
        self.diag.instrument_step(can_step as u64, || {
            self.state.step_multiple(can_step, &self.stimuli);
        });
        trace!("step end");
        if self.last_diag_time.elapsed().as_secs_f64() >= 5.0 {
            self.last_diag_time = Instant::now();
            let step = self.state.step_no();
            let diagstr = self.diag.format();
            let sim_time = self.state.time() as f64;
            let percent_complete = match self.sim_end_time {
                Some(t) => format!("[{:.1}%] ", 100.0 * self.state.time() / *t.to_seconds(self.timestep())),
                None => "".to_owned(),
            };
            info!(
                "{}t={:.2e} frame {:06} {}",
                percent_complete, sim_time, step, diagstr
            );
        }
        can_step as u32
    }
    pub fn step_multiple(&mut self, num_steps: u32) {
        let mut steps_remaining = num_steps;
        while steps_remaining != 0 {
            steps_remaining -= self.step_at_most(steps_remaining);
        }
    }
    pub fn step(&mut self) {
        self.step_multiple(1);
    }

    /// Returns the number of timesteps needed to reach the end time
    pub fn steps_until<T: Time>(&mut self, sim_end_time: T) -> u64 {
        let sim_end_step = sim_end_time.to_frame(self.state.timestep());
        let start_step = self.state.step_no();
        sim_end_step.saturating_sub(start_step)
    }

    pub fn step_until<T: Time>(&mut self, sim_end_time: T) {
        let sim_end_time = sim_end_time.to_frame(self.state.timestep());
        self.sim_end_time = Some(sim_end_time);
        let mut stepped = false;
        while self.state.step_no() < *sim_end_time {
            self.step_multiple(100);
            stepped = true;
        }
        if stepped {
            // render the final frame -- unless we already *have*
            self.render();
        }
        self.render_pool.join();
        self.sim_end_time = None;
    }
}