Start section 4.6

src/map_builders/cellular_automata.rs

@@ -3,6 +3,8 @@ use crate::{components::Position, spawner, Map, TileType, SHOW_MAPGEN_VISUALIZER
 use rltk::RandomNumberGenerator;
 use specs::prelude::*;
 use std::collections::HashMap;
+use crate::map_builders::common::remove_unreachable_areas_returning_most_distant;
+use super::common::generate_voronoi_spawn_regions;
 
 pub struct CellularAutomataBuilder {
     map: Map,
@@ -139,58 +141,14 @@ impl CellularAutomataBuilder {
         }
 
         // Find all tiles we can reach from the starting point
-        let map_starts: Vec<usize> = vec![start_idx];
+        let exit_tile = remove_unreachable_areas_returning_most_distant(&mut self.map, start_idx);
-        let dijkstra_map = rltk::DijkstraMap::new(
-            self.map.width,
-            self.map.height,
-            &map_starts,
-            &self.map,
-            200.0,
-        );
-        let mut exit_tile = (0, 0.0f32);
-        for (i, tile) in self.map.tiles.iter_mut().enumerate() {
-            if *tile == TileType::Floor {
-                let distance_to_start = dijkstra_map.map[i];
-
-                // We can't get to this tile - so we'll make it a wall
-                if distance_to_start == f32::MAX {
-                    *tile = TileType::Wall;
-                } else {
-                    // If it is further away than our current exit candidate, move the exit
-                    if distance_to_start > exit_tile.1 {
-                        exit_tile.0 = i;
-                        exit_tile.1 = distance_to_start;
-                    }
-                }
-            }
-        }
         self.take_snapshot();
 
         // Place the stairs
-        self.map.tiles[exit_tile.0] = TileType::DownStairs;
+        self.map.tiles[exit_tile] = TileType::DownStairs;
         self.take_snapshot();
 
         // Now we build a noise map for use in spawning entities later
-        let mut noise = rltk::FastNoise::seeded(rng.roll_dice(1, 65536) as u64);
+        self.noise_areas = generate_voronoi_spawn_regions(&self.map, &mut rng);
-        noise.set_noise_type(rltk::NoiseType::Cellular);
-        noise.set_frequency(0.08);
-        noise.set_cellular_distance_function(rltk::CellularDistanceFunction::Manhattan);
-
-        for y in 1..self.map.height - 1 {
-            for x in 1..self.map.width - 1 {
-                let idx = self.map.xy_idx(x, y);
-                if self.map.tiles[idx] == TileType::Floor {
-                    let cell_value_f = noise.get_noise(x as f32, y as f32) * 10240.0;
-                    let cell_value = cell_value_f as i32;
-
-                    #[allow(clippy::map_entry)]
-                    if self.noise_areas.contains_key(&cell_value) {
-                        self.noise_areas.get_mut(&cell_value).unwrap().push(idx);
-                    } else {
-                        self.noise_areas.insert(cell_value, vec![idx]);
-                    }
-                }
-            }
-        }
     }
 }

src/map_builders/common.rs

@@ -1,5 +1,6 @@
 use crate::{Map, Rect, TileType};
 use std::cmp::{max, min};
+use std::collections::HashMap;
 
 pub fn apply_room_to_map(map: &mut Map, room: &Rect) {
     for y in room.y1 + 1..=room.y2 {
@@ -29,3 +30,65 @@ pub fn apply_vertical_tunnel(map: &mut Map, y1: i32, y2: i32, x: i32) {
         }
     }
 }
+
+/// Searches a map, removes unreachable areas and returns the most distant tile.
+pub fn remove_unreachable_areas_returning_most_distant(map: &mut Map, start_idx: usize) -> usize {
+    map.populate_blocked();
+    let map_starts: Vec<usize> = vec![start_idx];
+    let dijkstra_map = rltk::DijkstraMap::new(
+        map.width as usize,
+        map.height as usize,
+        &map_starts,
+        map,
+        200.0,
+    );
+    let mut exit_tile = (0, 0.0f32);
+    for (i, tile) in map.tiles.iter_mut().enumerate() {
+        if *tile == TileType::Floor {
+            let distance_to_start = dijkstra_map.map[i];
+            // We can't get to this tile - so we'll make it a wall
+            if distance_to_start == std::f32::MAX {
+                *tile = TileType::Wall;
+            } else {
+                // If it is further away than our current exit candidate, move the exit
+                if distance_to_start > exit_tile.1 {
+                    exit_tile.0 = i;
+                    exit_tile.1 = distance_to_start;
+                }
+            }
+        }
+    }
+
+    exit_tile.0
+}
+
+/// Generates a Voronoi/cellular noise map of a region, and divides it into spawn regions.
+#[allow(clippy::map_entry)]
+pub fn generate_voronoi_spawn_regions(
+    map: &Map,
+    rng: &mut rltk::RandomNumberGenerator,
+) -> HashMap<i32, Vec<usize>> {
+    let mut noise_areas: HashMap<i32, Vec<usize>> = HashMap::new();
+    let mut noise = rltk::FastNoise::seeded(rng.roll_dice(1, 65536) as u64);
+    noise.set_noise_type(rltk::NoiseType::Cellular);
+    noise.set_frequency(0.08);
+    noise.set_cellular_distance_function(rltk::CellularDistanceFunction::Manhattan);
+
+    for y in 1..map.height - 1 {
+        for x in 1..map.width - 1 {
+            let idx = map.xy_idx(x, y);
+            if map.tiles[idx] == TileType::Floor {
+                let cell_value_f = noise.get_noise(x as f32, y as f32) * 10240.0;
+                let cell_value = cell_value_f as i32;
+
+                if noise_areas.contains_key(&cell_value) {
+                    noise_areas.get_mut(&cell_value).unwrap().push(idx);
+                } else {
+                    noise_areas.insert(cell_value, vec![idx]);
+                }
+            }
+        }
+    }
+
+    noise_areas
+}

src/map_builders/drunkard.rs

@@ -0,0 +1,76 @@
+use super::MapBuilder;
+use crate::{components::Position, spawner, Map, TileType, SHOW_MAPGEN_VISUALIZER};
+use rltk::RandomNumberGenerator;
+use specs::prelude::*;
+use std::collections::HashMap;
+
+pub struct DrunkardsWalkBuilder {
+    map: Map,
+    starting_position: Position,
+    depth: i32,
+    history: Vec<Map>,
+    noise_areas: HashMap<i32, Vec<usize>>,
+}
+
+impl MapBuilder for DrunkardsWalkBuilder {
+    fn build_map(&mut self) {
+        self.build();
+    }
+
+    fn spawn_entities(&mut self, ecs: &mut World) {
+        for area in self.noise_areas.iter() {
+            spawner::spawn_region(ecs, area.1, self.depth);
+        }
+    }
+
+    fn get_map(&self) -> Map {
+        self.map.clone()
+    }
+
+    fn get_starting_position(&self) -> Position {
+        self.starting_position
+    }
+
+    fn get_snapshot_history(&self) -> Vec<Map> {
+        self.history.clone()
+    }
+
+    fn take_snapshot(&mut self) {
+        if SHOW_MAPGEN_VISUALIZER {
+            let mut snapshot = self.map.clone();
+            for v in snapshot.revealed_tiles.iter_mut() {
+                *v = true;
+            }
+            self.history.push(snapshot);
+        }
+    }
+}
+
+impl DrunkardsWalkBuilder {
+    pub fn new(new_depth: i32) -> DrunkardsWalkBuilder {
+        DrunkardsWalkBuilder {
+            map: Map::new(new_depth),
+            starting_position: Position::default(),
+            depth: new_depth,
+            history: Vec::new(),
+            noise_areas: HashMap::new(),
+        }
+    }
+
+    #[allow(clippy::map_entry)]
+    fn build(&mut self) {
+        // let mut rng = RandomNumberGenerator::new();
+
+        // Set a central starting point
+        self.starting_position = Position {
+            x: self.map.width / 2,
+            y: self.map.height / 2,
+        };
+        let start_idx = self
+            .map
+            .xy_idx(self.starting_position.x, self.starting_position.y);
+        self.map.tiles[start_idx] = TileType::Floor;
+
+        // @TODO implement the rest
+    }
+}

src/map_builders/mod.rs

@@ -2,6 +2,7 @@ mod bsp_dungeon;
 mod bsp_interior;
 mod cellular_automata;
 mod common;
+mod drunkard;
 mod simple_map;
 
 use crate::{Map, Position};
@@ -9,6 +10,7 @@ use bsp_dungeon::BspDungeonBuilder;
 use bsp_interior::BspInteriorBuilder;
 use cellular_automata::CellularAutomataBuilder;
 use common::*;
+use drunkard::DrunkardsWalkBuilder;
 use simple_map::SimpleMapBuilder;
 use specs::prelude::*;
 
@@ -29,4 +31,5 @@ pub fn random_builder(new_depth: i32) -> Box<dyn MapBuilder> {
         3 => Box::new(CellularAutomataBuilder::new(new_depth)),
         _ => Box::new(SimpleMapBuilder::new(new_depth)),
     }
+    // Box::new(DrunkardsWalkBuilder::new(new_depth))
 }