terrain_forge/algorithms/
drunkard.rs1use crate::{Algorithm, Grid, Rng, Tile};
2
3#[derive(Debug, Clone)]
4pub struct DrunkardConfig {
5 pub floor_percent: f64,
6 pub max_iterations: usize,
7}
8
9impl Default for DrunkardConfig {
10 fn default() -> Self {
11 Self {
12 floor_percent: 0.4,
13 max_iterations: 50000,
14 }
15 }
16}
17
18pub struct DrunkardWalk {
19 config: DrunkardConfig,
20}
21
22impl DrunkardWalk {
23 pub fn new(config: DrunkardConfig) -> Self {
24 Self { config }
25 }
26}
27
28impl Default for DrunkardWalk {
29 fn default() -> Self {
30 Self::new(DrunkardConfig::default())
31 }
32}
33
34impl Algorithm<Tile> for DrunkardWalk {
35 fn generate(&self, grid: &mut Grid<Tile>, seed: u64) {
36 let mut rng = Rng::new(seed);
37 let (w, h) = (grid.width(), grid.height());
38 let target = ((w * h) as f64 * self.config.floor_percent) as usize;
39 let dirs: [(i32, i32); 4] = [(0, -1), (1, 0), (0, 1), (-1, 0)];
40
41 let mut x = w as i32 / 2;
42 let mut y = h as i32 / 2;
43 let mut floor_count = 0;
44
45 for _ in 0..self.config.max_iterations {
46 if floor_count >= target {
47 break;
48 }
49
50 if !grid.get(x, y).map(|t| t.is_floor()).unwrap_or(true) {
51 grid.set(x, y, Tile::Floor);
52 floor_count += 1;
53 }
54
55 let (dx, dy) = dirs[rng.range_usize(0, 4)];
56 let (nx, ny) = (x + dx, y + dy);
57 if nx > 0 && nx < w as i32 - 1 && ny > 0 && ny < h as i32 - 1 {
58 x = nx;
59 y = ny;
60 }
61 }
62 }
63
64 fn name(&self) -> &'static str {
65 "DrunkardWalk"
66 }
67}