Start hex grid and make tests pass

src/main.rs

@@ -1,19 +1,10 @@
 #![feature(array_zip)]
 
 use std::path::PathBuf;
-use rand::prelude::*;
 
 mod system;
 mod example_systems;
 
-use system::walker::{LocalRandomWalker, Walker};
-use system::grid::VectorStorage;
-use num_integer::Integer;
-use rand::rngs::SmallRng;
-use crate::system::grid::Position;
-use crate::system::model::DLASystem;
-use crate::system::Storage;
-
 use clap::Parser;
 use crate::example_systems::stick_probability;
 

src/system/grid.rs

@@ -73,32 +73,20 @@ impl VectorStorage {
         VectorStorage { grid_size, backing: vec![false; grid_size.pow(2) as usize] }
     }
 
-    pub fn linear_index(&self, position: &Position) -> usize {
-        assert!(position.x <= self.grid_size as i32 && -(self.grid_size as i32) <= position.x);
-        assert!(position.y <= self.grid_size as i32 && -(self.grid_size as i32) <= position.y);
-
-        let x = (position.x + (self.grid_size as i32) / 2) as usize;
-        let y = (position.y + (self.grid_size as i32) / 2) as usize;
-
-        return self.grid_size as usize * y + x
-    }
-
     /*
      * Convenience function for c-binding
      * */
     pub fn write(&mut self, position: &Position, val: bool) {
-        let index = self.linear_index(position);
-        self.backing[index] = val;
+        self.backing[position.linear_index(self.grid_size)] = val;
     }
 }
 
 impl Storage<Position> for VectorStorage {
     fn at(&self, position: &Position) -> bool {
-        return self.backing[self.linear_index(position)]
+        return self.backing[position.linear_index(self.grid_size)]
     }
 
     fn deposit(&mut self, position: &Position) {
-        let index = self.linear_index(position);
-        self.backing[index] = true;
+        self.backing[position.linear_index(self.grid_size)] = true;
     }
 }

src/system/hexagonal.rs

@@ -0,0 +1,51 @@
+use std::ops::Add;
+use bevy::render::color::HexColorError::Hex;
+use rand::Rng;
+use crate::system::GriddedPosition;
+use serde::{Serialize, Deserialize};
+
+#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize)]
+pub struct HexPosition {
+    pub q: i32,
+    pub r: i32,
+}
+
+impl Add for HexPosition {
+    type Output = Self;
+
+    fn add(self, rhs: Self) -> Self::Output {
+        HexPosition { q: self.q + rhs.q, r: self.r + rhs.r }
+    }
+}
+
+impl GriddedPosition for HexPosition {
+    const NEIGHBOURS: u32 = 6;
+
+    fn zero() -> Self {
+        HexPosition { q: 0, r: 0 }
+    }
+
+    fn spawn<R: Rng>(rng: &mut R, radius: f32) -> Self {
+        todo!()
+    }
+
+    fn abs(&self) -> f32 {
+        ((self.q.pow(2) + self.r.pow(2) + self.q * self.r) as f32).sqrt()
+    }
+
+    fn neighbour(&self, neighbour_index: u32) -> Self {
+        let neighbour_index = neighbour_index as usize;
+
+        const OFFSETS: [(i32, i32); 6] = [
+            (1, 0), (1, -1), (0, -1),
+            (-1, 0), (-1, 1), (0, 1),
+        ];
+
+        self.clone() + HexPosition { q: OFFSETS[neighbour_index].0, r: OFFSETS[neighbour_index].0 }
+    }
+
+    fn linear_index(&self, grid_size: u32) -> usize {
+        todo!()
+        // ((self.q + grid_size / 2) + grid_size * self.r) as usize
+    }
+}

src/system/mod.rs

@@ -1,14 +1,12 @@
-use std::f32::consts::PI;
 use std::ops::Add;
-use num_integer::Integer;
 use rand::Rng;
-use serde::{Deserialize, Serialize, Serializer};
-use crate::system::grid::VectorStorage;
+use serde::Serialize;
 
 pub mod walker;
 pub mod grid;
 pub mod model;
 pub mod nd;
+mod hexagonal;
 
 pub trait GriddedPosition: Add<Output=Self> + Serialize + Clone {
     const NEIGHBOURS: u32;

src/system/model.rs

@@ -1,14 +1,8 @@
-use std::f32::consts::PI;
-use std::fs::File;
-use std::io::Write;
 use std::io;
 use std::path::Path;
 use rand::prelude::*;
-use crate::system::{GriddedPosition, grid::Position, Storage};
-use crate::system::grid::VectorStorage;
-use crate::system::walker::{LocalRandomWalker, Walker};
-use serde::{Deserialize, Serialize};
-use crate::system::nd::{NDPosition, NDVectorStorage};
+use crate::system::{GriddedPosition, Storage};
+use crate::system::walker::Walker;
 
 pub struct DLASystem<R: Rng, P: GriddedPosition, S: Storage<P>, W: Walker<P>> {
     rng: R,

src/system/nd.rs

@@ -75,11 +75,11 @@ impl<const DIM: usize> GriddedPosition for NDPosition<DIM> {
             .sqrt();
 
         for i in 0..DIM {
-            a[i] = a[i] / norm;
+            a[i] = a[i] * radius / norm;
             b[i] = a[i] as i32;
         }
 
-        return Self(b)
+        return Self(b);
     }
 
     fn abs(&self) -> f32 {

src/system/walker.rs

@@ -1,6 +1,5 @@
-use num_integer::Integer;
 use rand::prelude::Rng;
-use crate::system::{GriddedPosition, grid::Position};
+use crate::system::GriddedPosition;
 
 pub trait Walker<P: GriddedPosition> {
     fn walk<R: Rng>(&self, rng: &mut R, position: &P) -> P;
@@ -22,35 +21,35 @@ mod test {
 
     #[test]
     fn uniformity() {
-        let walker = LocalRandomWalker::new();
+        let walker = LocalRandomWalker;
         let mut rng = SmallRng::from_rng(thread_rng()).unwrap();
         let mut results: Vec<Position> = vec![];
 
         let origin = &Position::zero();
 
-        let x: u32 = (1_000000_000);
+        let x: u32 = (1_000_000);
         for i in 0..x {
             results.push(walker.walk(&mut rng, origin));
         }
 
         let a = results
             .iter()
-            .filter(|a| **a == Position(0, 1))
+            .filter(|a| **a == Position { x: 0, y: 1 })
             .count();
 
         let b = results
             .iter()
-            .filter(|a| **a == Position(0, -1))
+            .filter(|a| **a == Position { x: 0, y: -1 })
             .count();
 
         let c = results
             .iter()
-            .filter(|a| **a == Position(1, 0))
+            .filter(|a| **a == Position { x: 1, y: 0 })
             .count();
 
         let d = results
             .iter()
-            .filter(|a| **a == Position(-1, 0))
+            .filter(|a| **a == Position { x: -1, y: 0 })
             .count();
 
         println!("{} {} {} {}", a as f32 / x as f32, b as f32 / x as f32, c as f32 / x as f32, d as f32 / x as f32);