feat(grid): generate maze

src/hex.rs

@@ -0,0 +1,14 @@
+use bevy::{color::palettes::css::BLACK, prelude::*};
+
+use bevy_prototype_lyon::{
+    draw::{Fill, Stroke},
+    entity::ShapeBundle,
+    path::PathBuilder,
+    plugin::ShapePlugin,
+};
+use rand::{thread_rng, Rng};
+
+pub(super) fn plugin(app: &mut App) {
+    app.add_plugins(ShapePlugin);
+    app.add_systems(Startup, setup_system);
+}

src/hexgrid/direction.rs

@@ -4,7 +4,7 @@ use hexx::EdgeDirection;
 pub(super) fn plugin(_app: &mut App) {}
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, Reflect)]
-pub enum HexDirection {
+pub enum Direction {
     Top,
     TopRight,
     BottomRight,
@@ -13,12 +13,8 @@ pub enum HexDirection {
     TopLeft,
 }
 
-impl HexDirection {
-    pub fn to_hexx_direction(self) -> EdgeDirection {
-        self.into()
-    }
-
-    pub const ALL: [HexDirection; 6] = [
+impl Direction {
+    pub const ALL: [Direction; 6] = [
         Self::Top,
         Self::TopRight,
         Self::BottomRight,
@@ -38,16 +34,3 @@ impl HexDirection {
         }
     }
 }
-
-impl From<HexDirection> for EdgeDirection {
-    fn from(value: HexDirection) -> Self {
-        match value {
-            HexDirection::Top => Self::FLAT_NORTH,
-            HexDirection::TopRight => Self::FLAT_NORTH_EAST,
-            HexDirection::BottomRight => Self::FLAT_SOUTH_EAST,
-            HexDirection::Bottom => Self::FLAT_SOUTH,
-            HexDirection::BottomLeft => Self::FLAT_SOUTH_WEST,
-            HexDirection::TopLeft => Self::FLAT_NORTH_WEST,
-        }
-    }
-}

src/hexgrid/grid.rs

@@ -1,4 +1,8 @@
-use bevy::{color::palettes::css::BLACK, prelude::*};
+use bevy::{
+    color::palettes::css::{BLACK, GREEN, RED},
+    prelude::*,
+    utils::hashbrown::HashMap,
+};
 
 use bevy_prototype_lyon::{
     draw::{Fill, Stroke},
@@ -6,7 +10,18 @@ use bevy_prototype_lyon::{
     path::PathBuilder,
     plugin::ShapePlugin,
 };
-use rand::{thread_rng, Rng};
+use rand::{prelude::SliceRandom, rngs::ThreadRng, thread_rng};
+
+use super::tile::{AxialCoord, Tile};
+
+const DIRECTIONS: [AxialCoord; 6] = [
+    AxialCoord { q: 1, r: 0 },  // Right
+    AxialCoord { q: 1, r: -1 }, // Top-right
+    AxialCoord { q: 0, r: -1 }, // Top-left
+    AxialCoord { q: -1, r: 0 }, // Left
+    AxialCoord { q: -1, r: 1 }, // Bottom-left
+    AxialCoord { q: 0, r: 1 },  // Bottom-right
+];
 
 pub struct HexGrid;
 
@@ -18,45 +33,45 @@ impl Plugin for HexGrid {
 }
 
 pub(super) fn setup_system(mut commands: Commands) {
-    let radius = 5;
-    let hex_positions = generate_hex_grix(radius);
+    let radius = 7;
+    let mut grid = generate_hex_grix(radius);
 
-    let hex_size = 30.;
-    let hex_height = hex_size * 2.;
-    let hex_width = (3.0_f32).sqrt() * hex_size;
+    let start_coord = AxialCoord::new(-radius, 0);
+    let end_coord = AxialCoord::new(radius, 0);
 
-    for (q, r) in hex_positions {
-        let x = hex_width * (q as f32 + r as f32 / 2.);
-        let y = hex_height * (r as f32 * 3. / 4.);
     let mut rng = thread_rng();
-        let walls: [bool; 6] = [
-            rng.gen(),
-            rng.gen(),
-            rng.gen(),
-            rng.gen(),
-            rng.gen(),
-            rng.gen(),
-        ];
+    generate_maze(&mut grid, start_coord, &mut rng);
 
-        add_hex_tile(&mut commands, Vec2::new(x, y), hex_size, walls);
-    }
+    render_maze(&mut commands, &mut grid, radius, start_coord, end_coord);
 }
 
-fn generate_hex_grix(radius: i32) -> Vec<(i32, i32)> {
-    let mut positions = Vec::new();
+fn generate_hex_grix(radius: i32) -> HashMap<AxialCoord, Tile> {
+    let mut grid = HashMap::new();
 
     for q in -radius..=radius {
         let r1 = (-radius).max(-q - radius);
         let r2 = radius.min(-q + radius);
 
         for r in r1..=r2 {
-            positions.push((q, r));
+            let coord = AxialCoord::new(q, r);
+            let tile = Tile {
+                position: coord,
+                walls: [true; 6],
+                visited: false,
+            };
+            grid.insert(coord, tile);
         }
     }
-    positions
+    grid
 }
 
-fn add_hex_tile(commands: &mut Commands, position: Vec2, size: f32, walls: [bool; 6]) {
+fn add_hex_tile(
+    commands: &mut Commands,
+    position: Vec2,
+    size: f32,
+    walls: [bool; 6],
+    fill_color: Color,
+) {
     let hex_points = (0..6)
         .map(|i| {
             let angle_deg = 60. * i as f32 - 30.;
@@ -73,6 +88,7 @@ fn add_hex_tile(commands: &mut Commands, position: Vec2, size: f32, walls: [bool
     path_builder.close();
     let hexagon = path_builder.build();
 
+    // Create the hexagon fill
     commands.spawn((
         ShapeBundle {
             path: hexagon,
@@ -82,9 +98,10 @@ fn add_hex_tile(commands: &mut Commands, position: Vec2, size: f32, walls: [bool
             },
             ..default()
         },
-        Fill::color(Color::srgb(0.8, 0.8, 0.8)),
+        Fill::color(fill_color),
     ));
 
+    // Draw walls
     for i in 0..6 {
         if walls[i] {
             let start = hex_points[i];
@@ -108,3 +125,70 @@ fn add_hex_tile(commands: &mut Commands, position: Vec2, size: f32, walls: [bool
         }
     }
 }
+
+fn generate_maze(
+    grid: &mut HashMap<AxialCoord, Tile>,
+    current_coord: AxialCoord,
+    rng: &mut ThreadRng,
+) {
+    {
+        let current_tile = grid.get_mut(&current_coord).unwrap();
+        current_tile.visit();
+    }
+
+    let mut directions = DIRECTIONS.clone();
+    directions.shuffle(rng);
+
+    for (i, direction) in directions.iter().enumerate() {
+        let neightbor_coord = AxialCoord {
+            q: current_coord.q + direction.q,
+            r: current_coord.r + direction.r,
+        };
+
+        if let Some(neightbor_tile) = grid.get(&neightbor_coord) {
+            if !neightbor_tile.visited {
+                // Remove the wall between current_tile and neighbor_tile
+                {
+                    let current_tile = grid.get_mut(&current_coord).unwrap();
+                    current_tile.walls[i] = false;
+                }
+                {
+                    let neightbor_tile = grid.get_mut(&neightbor_coord).unwrap();
+                    neightbor_tile.walls[opposite_wall(i)] = false;
+                }
+                // Recurse with the neighbor tile
+                generate_maze(grid, neightbor_coord, rng);
+            }
+        }
+    }
+}
+
+fn render_maze(
+    commands: &mut Commands,
+    grid: &mut HashMap<AxialCoord, Tile>,
+    radius: i32,
+    start_coord: AxialCoord,
+    end_coord: AxialCoord,
+) {
+    let hex_size = 30.;
+    let hex_height = hex_size * 2.;
+    let hex_width = (3.0_f32).sqrt() * hex_size;
+
+    for tile in grid.values() {
+        let (q, r) = (tile.position.q, tile.position.r);
+        let x = hex_width * (q as f32 + r as f32 / 2.);
+        let y = hex_height * (r as f32 * 3. / 4.);
+        let mut fill_color = Color::srgb(0.8, 0.8, 0.8);
+        if tile.position == start_coord {
+            fill_color = GREEN.into();
+        } else if tile.position == end_coord {
+            fill_color = RED.into();
+        }
+
+        add_hex_tile(commands, Vec2::new(x, y), hex_size, tile.walls, fill_color);
+    }
+}
+
+fn opposite_wall(index: usize) -> usize {
+    (index + 3) % 6
+}

src/hexgrid/mod.rs

@@ -4,7 +4,9 @@ use bevy::{
 };
 use bevy_prototype_lyon::plugin::ShapePlugin;
 use grid::setup_system;
+pub mod direction;
 pub mod grid;
+pub mod tile;
 
 pub struct HexGrid;
 

src/hexgrid/tile.rs

@@ -0,0 +1,24 @@
+#[derive(Debug, Clone)]
+pub struct Tile {
+    pub position: AxialCoord,
+    pub walls: [bool; 6],
+    pub visited: bool,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub struct AxialCoord {
+    pub q: i32,
+    pub r: i32,
+}
+
+impl Tile {
+    pub fn visit(&mut self) {
+        self.visited = true
+    }
+}
+
+impl AxialCoord {
+    pub fn new(q: i32, r: i32) -> Self {
+        Self { q, r }
+    }
+}