feat: swap rng with ChaCha8 to make the simulation deterministic + ou…

…tput agent position at step 200 to compare them with the ecs-experiment branch

flockers/Cargo.toml

@@ -18,7 +18,8 @@ readme = "README.md"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-krabmaga = "0.4.*"
+krabmaga = {path = "../../krABMaga"}
+rand_chacha = "0.3.1"
 
 [features]
 parallel = ["krabmaga/parallel"]

flockers/src/main.rs

@@ -27,16 +27,18 @@ pub static MOMENTUM: f32 = 1.0;
 pub static JUMP: f32 = 0.7;
 pub static DISCRETIZATION: f32 = 10.0 / 1.5;
 pub static TOROIDAL: bool = true;
+pub static SEED: u64 = 1337;
 
 // Main used when only the simulation should run, without any visualization.
 #[cfg(not(any(feature = "visualization", feature = "visualization_wasm")))]
 fn main() {
     let step = 200;
 
     let dim = (800., 800.);
-    let num_agents = 64000;
-    let state = Flocker::new(dim, num_agents);
-    let _ = simulate_old!(state, step, 1, Info::Normal);
+    let num_agents = 200;
+    let mut state = Flocker::new(dim, num_agents);
+    // Outputs the positions of the 200 agents at step 200. Compare those with the ecs-experiment branch to verify the ecs-experiment branch is correct.
+    let _ = simulate_old!(&mut state, step, 1, Info::Verbose);
 }
 
 // Main used when a visualization feature is applied.

flockers/src/model/bird.rs

@@ -3,12 +3,15 @@ use krabmaga::engine::agent::Agent;
 use krabmaga::engine::fields::field_2d::{toroidal_distance, toroidal_transform, Location2D};
 use krabmaga::engine::location::Real2D;
 use krabmaga::engine::state::State;
-use krabmaga::rand;
+use krabmaga::{rand, Uniform};
 use krabmaga::rand::Rng;
 use std::hash::{Hash, Hasher};
+use rand_chacha::ChaCha8Rng;
+use rand_chacha::rand_core::SeedableRng;
 
 use crate::model::state::Flocker;
-use crate::{AVOIDANCE, COHESION, CONSISTENCY, JUMP, MOMENTUM, RANDOMNESS};
+use crate::{AVOIDANCE, COHESION, CONSISTENCY, JUMP, MOMENTUM, RANDOMNESS, SEED};
+use krabmaga::Distribution;
 
 #[derive(Clone, Copy)]
 pub struct Bird {
@@ -99,12 +102,19 @@ impl Agent for Bird {
                 y: -y_cohe / 10.0,
             };
 
-            //randomness
-            let mut rng = rand::thread_rng();
-            let r1: f32 = rng.gen();
-            let x_rand = r1 * 2.0 - 1.0;
-            let r2: f32 = rng.gen();
-            let y_rand = r2 * 2.0 - 1.0;
+            //randomness - uses the same rng of the ecs-experiment branch
+            let mut rng = ChaCha8Rng::seed_from_u64(SEED);
+            rng.set_stream(self.id as u64 + state.step);
+            let mut range = Uniform::new(0.0f32, 1.0);
+            let r1: f32 = range.sample(&mut rng);
+            let x_rand = r1 * 2. - 1.;
+            let r2: f32 = range.sample(&mut rng);
+            let y_rand = r2 * 2. - 1.;
+            // let mut rng = rand::thread_rng();
+            // let r1: f32 = rng.gen();
+            // let x_rand = r1 * 2.0 - 1.0;
+            // let r2: f32 = rng.gen();
+            // let y_rand = r2 * 2.0 - 1.0;
 
             let square = (x_rand * x_rand + y_rand * y_rand).sqrt();
             randomness = Real2D {
@@ -138,6 +148,9 @@ impl Agent for Bird {
         let loc_y = toroidal_transform(self.loc.y + dy, height);
 
         self.loc = Real2D { x: loc_x, y: loc_y };
+        if state.step == 200 {
+            println!("bird {} step {} - cohesion {}, avoidance {}, consistency {}, randomness {}, mom {}, loc_x {} loc_y {}", self.id, state.step, cohesion, avoidance, consistency, randomness, mom, loc_x, loc_y);
+        }
         drop(vec);
         state
             .field1
@@ -147,8 +160,8 @@ impl Agent for Bird {
 
 impl Hash for Bird {
     fn hash<H>(&self, state: &mut H)
-    where
-        H: Hasher,
+        where
+            H: Hasher,
     {
         self.id.hash(state);
     }

flockers/src/model/state.rs

@@ -1,13 +1,16 @@
 use crate::model::bird::Bird;
-use crate::{DISCRETIZATION, TOROIDAL};
+use crate::{DISCRETIZATION, SEED, TOROIDAL};
 use krabmaga::engine::fields::field::Field;
 use krabmaga::engine::fields::field_2d::Field2D;
 use krabmaga::engine::location::Real2D;
 use krabmaga::engine::schedule::Schedule;
 use krabmaga::engine::state::State;
-use krabmaga::rand;
+use krabmaga::{rand, Uniform};
+use krabmaga::Distribution;
 use krabmaga::rand::Rng;
 use std::any::Any;
+use rand_chacha::ChaCha8Rng;
+use rand_chacha::rand_core::SeedableRng;
 
 pub struct Flocker {
     pub step: u64,
@@ -35,11 +38,13 @@ impl State for Flocker {
     }
 
     fn init(&mut self, schedule: &mut Schedule) {
-        let mut rng = rand::thread_rng();
         // Should be moved in the init method on the model exploration changes
         for bird_id in 0..self.initial_flockers {
-            let r1: f32 = rng.gen();
-            let r2: f32 = rng.gen();
+            let mut rng = ChaCha8Rng::seed_from_u64(SEED);
+            let range = Uniform::new(0.0f32, 1.0);
+            rng.set_stream(bird_id as u64);
+            let r1: f32 = range.sample(&mut rng);
+            let r2: f32 = range.sample(&mut rng);
             let last_d = Real2D { x: 0., y: 0. };
             let loc = Real2D {
                 x: self.dim.0 * r1,
@@ -53,6 +58,7 @@ impl State for Flocker {
 
     fn update(&mut self, _step: u64) {
         self.field1.lazy_update();
+        self.step += 1;
     }
 
     fn as_any(&self) -> &dyn Any {