fdtd-coremem/src/driver.rs

use crate::geom::{Coord, Meters, Region, Vec3};
use crate::mat::{self, GenericMaterial, Material, Pml};
use crate::meas::{self, AbstractMeasurement};
use crate::real::{R32, Real};
use crate::render::{self, MultiRenderer, Renderer};
use crate::sim::{GenericSim, SimState};
use crate::stim::AbstractStimulus;

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

pub struct Driver<R=R32, M=GenericMaterial<R>> {
    pub state: SimState<R, M>,
    renderer: Arc<MultiRenderer<SimState<R, M>>>,
    // TODO: use Rayon's thread pool?
    render_pool: ThreadPool,
    render_channel: (SyncSender<()>, Receiver<()>),
    time_spent_stepping: Duration,
    time_spent_on_stimuli: Duration,
    time_spent_prepping_render: Duration,
    time_spent_blocked_on_render: Duration,
    time_spent_rendering: Arc<Mutex<Duration>>,
    measurements: Vec<Box<dyn AbstractMeasurement>>,
    stimuli: StimuliAdapter,
    start_time: Instant,
    last_diag_time: Instant,
}

impl<R: Real, M: Default> Driver<R, M> {
    pub fn new<C: Coord>(size: C, feature_size: f32) -> Self {
        Driver {
            state: SimState::new(size.to_index(feature_size), feature_size),
            renderer: Arc::new(MultiRenderer::new()),
            render_pool: ThreadPool::new(3),
            render_channel: sync_channel(0),
            time_spent_stepping: Default::default(),
            time_spent_on_stimuli: Default::default(),
            time_spent_prepping_render: Default::default(),
            time_spent_blocked_on_render: Default::default(),
            time_spent_rendering: Default::default(),
            measurements: vec![
                Box::new(meas::Time),
                Box::new(meas::Meta),
                Box::new(meas::Energy::world()),
                Box::new(meas::Power::world()),
            ],
            stimuli: StimuliAdapter::new(),
            start_time: Instant::now(),
            last_diag_time: Instant::now(),
        }
    }
}

impl<R: Real, M: Material<R>> Driver<R, M> {
    pub fn add_stimulus<S: AbstractStimulus + 'static>(&mut self, s: S) {
        self.stimuli.push(Box::new(s))
    }

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

    pub fn set_steps_per_stim(&mut self, steps_per_stim: u64) {
        self.stimuli.frame_interval = steps_per_stim;
    }
}

impl<R: Real, M: Material<R> + Clone> Driver<R, M> {
    pub fn fill_region<Reg: Region>(&mut self, region: &Reg, mat: M) {
        self.state.fill_region(region, mat);
    }
}

impl<R: Real, M: Material<R> + Send + Sync + 'static> Driver<R, M> {
    pub fn dyn_state(&mut self) -> &mut dyn GenericSim {
        &mut self.state
    }

    fn add_renderer<Rend: Renderer<SimState<R, M>> + 'static>(
        &mut self, renderer: Rend, name: &str, step_frequency: u64
    ) {
        info!("render to {} at f={}", name, step_frequency);
        self.renderer.push(renderer, step_frequency);
    }

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

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

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

impl<R: Real + Send + Sync + Serialize, M: Material<R> + Serialize + Send + Sync + 'static> Driver<R, M> {
    pub fn add_serializer_renderer(&mut self, out_base: &str, step_frequency: u64) {
        let fmt_str = format!("{out_base}{{step_no}}.bc", out_base=out_base);
        self.add_renderer(render::SerializerRenderer::new_static(&*fmt_str), &*fmt_str, step_frequency);
    }
}

impl<R, M> Driver<R, M>
where
    R: Real + Send + Sync + Serialize + for<'a> Deserialize<'a>,
    M: Material<R> + Serialize + for<'a> Deserialize<'a> + Send + Sync + 'static,
{
    pub fn add_state_file(&mut self, state_file: &str, snapshot_frequency: u64) {
        let ser = render::SerializerRenderer::new(state_file);
        if let Some(state) = ser.try_load() {
            self.state = state.state;
        }
        self.add_renderer(ser, state_file, snapshot_frequency);
    }
}

impl<R: Real + Send + Sync + 'static, M: Material<R> + Clone + Default + Send + Sync + 'static> Driver<R, M> {
    fn render(&mut self) {
        let prep_start = Instant::now();
        let their_state = self.state.clone();
        let their_measurements = self.measurements.clone();
        let renderer = self.renderer.clone();
        let time_spent_rendering = self.time_spent_rendering.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");
            let start_time = Instant::now();
            renderer.render(&their_state, &*their_measurements, Default::default());
            *time_spent_rendering.lock().unwrap() += start_time.elapsed();
            trace!("render end");
        });
        self.time_spent_prepping_render += prep_start.elapsed();
        let block_start = Instant::now();
        self.render_channel.1.recv().unwrap();
        self.time_spent_blocked_on_render += block_start.elapsed();
    }
    pub fn step(&mut self) {
        if self.stimuli.should_apply(self.state.step_no()) {
            trace!("stimuli begin");
            let start_time = Instant::now();
            self.state.apply_stimulus(&self.stimuli);
            self.time_spent_on_stimuli += start_time.elapsed();
            trace!("stimuli end");
        }

        if self.renderer.any_work_for_frame(self.state.step_no()) {
            self.render();
        }

        trace!("step begin");
        let start_time = Instant::now();
        self.state.step();
        self.time_spent_stepping += start_time.elapsed();
        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 step_time = self.time_spent_stepping.as_secs_f64();
            let stim_time = self.time_spent_on_stimuli.as_secs_f64();
            let render_time = self.time_spent_rendering.lock().unwrap().as_secs_f64();
            let render_prep_time = self.time_spent_prepping_render.as_secs_f64();
            let block_time = self.time_spent_blocked_on_render.as_secs_f64();
            let overall_time = self.start_time.elapsed().as_secs_f64();
            let fps = (self.state.step_no() as f64) / overall_time;
            let sim_time = self.state.time() as f64;
            info!(
                "t={:.2e} frame {:06} fps: {:6.2} (sim: {:.1}s, stim: {:.1}s, [render: {:.1}s], blocked: {:.1}s, render_prep: {:.1}s, other: {:.1}s)",
                sim_time,
                step,
                fps,
                step_time,
                stim_time,
                render_time,
                block_time,
                render_prep_time,
                overall_time - step_time - stim_time - block_time - render_prep_time,
            );
        }
    }

    pub fn step_until(&mut self, deadline: f32) {
        while self.dyn_state().time() < deadline {
            self.step();
        }
        // render the final frame
        self.render();
        self.render_pool.join();
    }
}

impl<R: Real, M: Material<R> + From<mat::Pml<R>>> Driver<R, M> {
    pub fn add_pml_boundary<C: Coord>(&mut self, thickness: C) {
        let timestep = self.state.timestep();
        self.state.fill_boundary_using(thickness, |boundary_ness| {
            let b = boundary_ness.elem_pow(3.0);
            let conductivity = b * (0.5 / timestep);
            Pml::new(conductivity).into()
        });
    }
}

impl<R: Real, M: Material<R> + From<mat::Conductor<R>>> Driver<R, M> {
    pub fn add_classical_boundary<C: Coord>(&mut self, thickness: C) {
        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::db::conductor(iso_cond);
            iso_conductor.into()
        });
    }
}

/// Adapts the stimuli to be applied only every so often, to improve perf
struct StimuliAdapter {
    stim: Vec<Box<dyn AbstractStimulus>>,
    /// How many frames to go between applications of the stimulus.
    frame_interval: u64,
}

impl AbstractStimulus for StimuliAdapter {
    fn at(&self, t_sec: f32, pos: Meters) -> Vec3<f32> {
        self.stim.at(t_sec, pos) * (self.frame_interval as f32)
    }
}

impl StimuliAdapter {
    fn new() -> Self {
        Self {
            stim: Default::default(),
            frame_interval: 1,
        }
    }
    fn should_apply(&self, frame: u64) -> bool {
        frame % self.frame_interval == 0
    }
    fn push(&mut self, s: Box<dyn AbstractStimulus>) {
        self.stim.push(s)
    }
}