Use a HashMap instead of a BTreeMap in Scheduler's internals. Doesn't

affect determistic simulation, but yields a crazy speedup. #54

- 8 hours of downtown: 122s to 102s!!!
- prebake: 181s to 160s

geom/src/time.rs

@@ -1,6 +1,7 @@
 use std::error::Error;
 use std::{cmp, ops};
 
+use ordered_float::NotNan;
 use serde::{Deserialize, Serialize};
 
 use crate::{trim_f64, Duration};
@@ -17,6 +18,12 @@ impl Ord for Time {
     }
 }
 
+impl std::hash::Hash for Time {
+    fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
+        NotNan::new(self.0).unwrap().hash(state);
+    }
+}
+
 impl Time {
     pub const START_OF_DAY: Time = Time(0.0);
 

sim/src/pandemic/pandemic.rs

@@ -29,7 +29,7 @@ pub struct PandemicModel {
 }
 
 // You can schedule callbacks in the future by doing scheduler.push(future time, one of these)
-#[derive(Serialize, Deserialize, PartialEq, Eq, PartialOrd, Ord, Clone, Debug)]
+#[derive(Serialize, Deserialize, PartialEq, Eq, Hash, PartialOrd, Ord, Clone, Debug)]
 pub enum Cmd {
     BecomeHospitalized(PersonID),
     BecomeQuarantined(PersonID),

sim/src/scheduler.rs

@@ -1,6 +1,6 @@
 use std::cmp::Ordering;
-use std::collections::btree_map::Entry;
+use std::collections::hash_map::Entry;
-use std::collections::{BTreeMap, BinaryHeap};
+use std::collections::{BinaryHeap, HashMap};
 
 use serde::{Deserialize, Serialize};
 
@@ -38,7 +38,7 @@ impl Command {
         }
     }
 
-    pub fn to_type(&self) -> CommandType {
+    fn to_type(&self) -> CommandType {
         match self {
             Command::SpawnCar(ref create, _) => CommandType::Car(create.vehicle.id),
             Command::SpawnPed(ref create) => CommandType::Ped(create.id),
@@ -57,8 +57,8 @@ impl Command {
 
 /// A smaller version of Command that satisfies many more properties. Only one Command per
 /// CommandType may exist at a time.
-#[derive(Serialize, Deserialize, PartialEq, Eq, PartialOrd, Ord, Clone, Debug)]
+#[derive(Serialize, Deserialize, PartialEq, Eq, Hash, PartialOrd, Ord, Clone, Debug)]
-pub enum CommandType {
+enum CommandType {
     StartTrip(TripID),
     Car(CarID),
     CarLaggyHead(CarID),
@@ -100,7 +100,7 @@ impl Ord for Item {
 #[derive(Clone, Serialize, Deserialize)]
 pub struct Scheduler {
     items: BinaryHeap<Item>,
-    queued_commands: BTreeMap<CommandType, (Command, Time)>,
+    queued_commands: HashMap<CommandType, (Command, Time)>,
 
     latest_time: Time,
     last_time: Time,
@@ -112,7 +112,7 @@ impl Scheduler {
     pub fn new() -> Scheduler {
         Scheduler {
             items: BinaryHeap::new(),
-            queued_commands: BTreeMap::new(),
+            queued_commands: HashMap::new(),
             latest_time: Time::START_OF_DAY,
             last_time: Time::START_OF_DAY,
             delta_times: Histogram::new(),
@@ -174,17 +174,6 @@ impl Scheduler {
         self.queued_commands.remove(&cmd.to_type());
     }
 
-    // TODO Should panic if a command of this type isn't scheduled. But currently failing
-    // unexpectedly.
-    pub fn must_cancel_by_type(&mut self, cmd: CommandType) {
-        if self.queued_commands.remove(&cmd).is_none() {
-            println!(
-                "must_cancel_by_type({:?}) didn't find a matching command",
-                cmd
-            );
-        }
-    }
-
     /// This next command might've actually been rescheduled to a later time; the caller won't know
     /// that here.
     pub fn peek_next_time(&self) -> Option<Time> {