debug a car in a different color

editor/color_scheme

@@ -234,6 +234,12 @@
       0.0,
       1.0
     ],
+    "DebugCar": [
+      0.0,
+      0.0,
+      1.0,
+      0.8
+    ],
     "MovingCar": [
       0.0,
       1.0,

editor/src/colors.rs

@@ -55,6 +55,7 @@ pub enum Colors {
     YieldTurn,
     StopTurn,
 
+    DebugCar,
     MovingCar,
     StuckCar,
     ParkedCar,

editor/src/ui.rs

@@ -370,6 +370,7 @@ impl UI {
             return c;
         }
         match self.sim_ctrl.sim.get_car_state(id) {
+            CarState::Debug => ezgui::shift_color(self.cs.get(Colors::DebugCar), id.0),
             CarState::Moving => ezgui::shift_color(self.cs.get(Colors::MovingCar), id.0),
             CarState::Stuck => ezgui::shift_color(self.cs.get(Colors::StuckCar), id.0),
             CarState::Parked => ezgui::shift_color(self.cs.get(Colors::ParkedCar), id.0),

sim/src/driving.rs

@@ -162,6 +162,8 @@ impl Car {
                     }
 
                     constraints.push(accel);
+                } else if self.debug {
+                    println!("  {} is {} behind {}. Lookahead dist {} + following dist {} is less than that, so ignore them", self.id, dist_behind_other, other.id, dist_to_lookahead, other_vehicle.following_dist());
                 }
             }
 
@@ -475,7 +477,9 @@ impl DrivingSimState {
 
     pub fn get_car_state(&self, c: CarID) -> CarState {
         if let Some(driving) = self.cars.get(&c) {
-            if driving.speed > kinematics::EPSILON_SPEED {
+            if driving.debug {
+                CarState::Debug
+            } else if driving.speed > kinematics::EPSILON_SPEED {
                 CarState::Moving
             } else {
                 CarState::Stuck

sim/src/lib.rs

@@ -233,6 +233,7 @@ pub enum CarState {
     Moving,
     Stuck,
     Parked,
+    Debug,
 }
 
 // TODO Don't just alias types; assert that time, dist, and speed are always positive