cleanup agent structs

src/agent.rs

@@ -9,9 +9,7 @@ use std::fmt::{Display, Formatter};
 pub struct Agent {
     pub x: f32,
     pub y: f32,
-    pub angle: f32,
-    pub population_id: usize,
-    pub i: usize,
+    angle: f32,
 }
 
 impl Display for Agent {
@@ -22,20 +20,12 @@ impl Display for Agent {
 
 impl Agent {
     /// Construct a new agent with random parameters.
-    pub fn new<R: Rng + ?Sized>(
-        width: usize,
-        height: usize,
-        id: usize,
-        rng: &mut R,
-        i: usize,
-    ) -> Self {
+    pub fn new<R: Rng + ?Sized>(width: usize, height: usize, rng: &mut R) -> Self {
         let (x, y, angle) = rng.gen::<(f32, f32, f32)>();
         Agent {
             x: x * width as f32,
             y: y * height as f32,
             angle: angle * TAU,
-            population_id: id,
-            i,
         }
     }
 

src/model.rs

@@ -73,9 +73,9 @@ impl Model {
         }
 
         let mut grids: Vec<Grid> = Vec::new();
-        for pop in 0..n_populations {
+        for _ in 0..n_populations {
             let agents = (0..particles_per_grid)
-                .map(|i| Agent::new(width, height, pop, &mut rng, i))
+                .map(|_| Agent::new(width, height, &mut rng))
                 .collect();
             grids.push(Grid::new(width, height, &mut rng, agents));
         }