cellular automata and bsp interiors

src/map_builders/cellular_automata.rs

@@ -0,0 +1,171 @@
+use super::{spawner, Map, MapBuilder, Position, TileType, SHOW_MAPGEN};
+use rltk::RandomNumberGenerator;
+use specs::prelude::*;
+use std::collections::HashMap;
+
+const PASSES: i32 = 15;
+
+pub struct CellularAutomataBuilder {
+    map: Map,
+    starting_position: Position,
+    depth: i32,
+    history: Vec<Map>,
+    noise_areas: HashMap<i32, Vec<usize>>,
+}
+
+impl MapBuilder for CellularAutomataBuilder {
+    fn build_map(&mut self, rng: &mut RandomNumberGenerator) {
+        return self.build(rng);
+    }
+    fn spawn_entities(&mut self, ecs: &mut World) {
+        for area in self.noise_areas.iter() {
+            spawner::spawn_region(ecs, area.1, self.depth);
+        }
+    }
+    //  Getters
+    fn get_map(&mut self) -> Map {
+        return self.map.clone();
+    }
+    fn get_starting_pos(&mut self) -> Position {
+        return self.starting_position.clone();
+    }
+    // Mapgen visualisation stuff
+    fn get_snapshot_history(&self) -> Vec<Map> {
+        return self.history.clone();
+    }
+    fn take_snapshot(&mut self) {
+        if SHOW_MAPGEN {
+            let mut snapshot = self.map.clone();
+            for v in snapshot.revealed_tiles.iter_mut() {
+                *v = true;
+            }
+            self.history.push(snapshot);
+        }
+    }
+}
+
+impl CellularAutomataBuilder {
+    pub fn new(new_depth: i32) -> CellularAutomataBuilder {
+        CellularAutomataBuilder {
+            map: Map::new(new_depth),
+            starting_position: Position { x: 0, y: 0 },
+            depth: new_depth,
+            history: Vec::new(),
+            noise_areas: HashMap::new(),
+        }
+    }
+
+    fn build(&mut self, rng: &mut RandomNumberGenerator) {
+        // Set 55% of map to floor
+        for y in 1..self.map.height - 1 {
+            for x in 1..self.map.width - 1 {
+                let roll = rng.roll_dice(1, 100);
+                let idx = self.map.xy_idx(x, y);
+                if roll > 55 {
+                    self.map.tiles[idx] = TileType::Floor
+                } else {
+                    self.map.tiles[idx] = TileType::Wall
+                }
+            }
+        }
+        self.take_snapshot();
+
+        // Iteratively apply cellular automata rules
+        for _i in 0..PASSES {
+            let mut newtiles = self.map.tiles.clone();
+
+            for y in 1..self.map.height - 1 {
+                for x in 1..self.map.width - 1 {
+                    let idx = self.map.xy_idx(x, y);
+                    let mut neighbours = 0;
+                    if self.map.tiles[idx - 1] == TileType::Wall {
+                        neighbours += 1;
+                    }
+                    if self.map.tiles[idx + 1] == TileType::Wall {
+                        neighbours += 1;
+                    }
+                    if self.map.tiles[idx - self.map.width as usize] == TileType::Wall {
+                        neighbours += 1;
+                    }
+                    if self.map.tiles[idx + self.map.width as usize] == TileType::Wall {
+                        neighbours += 1;
+                    }
+                    if self.map.tiles[idx - (self.map.width as usize - 1)] == TileType::Wall {
+                        neighbours += 1;
+                    }
+                    if self.map.tiles[idx - (self.map.width as usize + 1)] == TileType::Wall {
+                        neighbours += 1;
+                    }
+                    if self.map.tiles[idx + (self.map.width as usize - 1)] == TileType::Wall {
+                        neighbours += 1;
+                    }
+                    if self.map.tiles[idx + (self.map.width as usize + 1)] == TileType::Wall {
+                        neighbours += 1;
+                    }
+
+                    if neighbours > 4 || neighbours == 0 {
+                        newtiles[idx] = TileType::Wall;
+                    } else {
+                        newtiles[idx] = TileType::Floor;
+                    }
+                }
+            }
+            self.map.tiles = newtiles.clone();
+            self.take_snapshot();
+        }
+
+        // Find a starting point; start at the middle and walk left until we find an open tile
+        self.starting_position = Position { x: self.map.width / 2, y: self.map.height / 2 };
+        let mut start_idx = self.map.xy_idx(self.starting_position.x, self.starting_position.y);
+        while self.map.tiles[start_idx] != TileType::Floor {
+            self.starting_position.x -= 1;
+            start_idx = self.map.xy_idx(self.starting_position.x, self.starting_position.y);
+        }
+
+        // Find all tiles we can reach from the starting point
+        let map_starts: Vec<usize> = vec![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 == 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;
+                    }
+                }
+            }
+        }
+        self.take_snapshot();
+
+        self.map.tiles[exit_tile.0] = TileType::DownStair;
+        self.take_snapshot();
+
+        // Build noise map for spawning entities
+        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..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;
+
+                    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]);
+                    }
+                }
+            }
+        }
+    }
+}