/godot-procedural-generation

Procedural Algorithm Recipes (load on demand)

MANDATORY when implementing drunkard walk, BSP, noise biomes, WFC lite, or loot tables beyond the Golden Path scripts. All heavy work off-thread; SceneTree commits on main thread only.

Drunkard's walk (organic caves)

func generate_dungeon(width: int, height: int, fill_percent: float = 0.4) -> Array:
    var grid: Array = []
    for y in height:
        grid.append(Array().duplicate(width))  # 1 = wall
    var x := width / 2
    var y := height / 2
    var floor_tiles := 0
    var target := int(width * height * fill_percent)
    var rng := RandomNumberGenerator.new()
    while floor_tiles < target:
        if grid[y][x] == 1:
            grid[y][x] = 0
            floor_tiles += 1
        match rng.randi() % 4:
            0: x = clampi(x + 1, 0, width - 1)
            1: x = clampi(x - 1, 0, width - 1)
            2: y = clampi(y + 1, 0, height - 1)
            3: y = clampi(y - 1, 0, height - 1)
    return grid

See drunknard_walk_path.gd.

Perlin / FastNoiseLite biomes

var noise := FastNoiseLite.new()
noise.seed = run_seed
noise.frequency = 0.05
# Prefer noise.get_image() once — never sample per frame in _process

See fast_noise_noise2d_master.gd.

BSP room split

Full BSPRoom.split() recursion — bsp_tree_rooms.gd. Validate min_size before split to avoid degenerate leaves.

Random loot tables

func roll_rarity(rng: RandomNumberGenerator) -> String:
    var roll := rng.randf()
    if roll < 0.6: return "common"
    if roll < 0.85: return "uncommon"
    if roll < 0.95: return "rare"
    return "legendary"

Pair with godot-resource-data-patterns for ItemData resources.

WFC lite loop

Always cap iterations — impossible adjacency rules can spin forever. See wave_function_collapse_lite.gd.

Expert: graph-before-geometry

Build room graph with AStar2D first — validate reachability before spawning tiles. proc_gen_graph_layout.gd.

Expert: marching cubes / ArrayMesh

Vertices/normals in worker thread → add_surface_from_arrays on main thread → create_trimesh_collision() only for active chunk. proc_gen_marching_cubes_base.gd.

Serialization contract

Persist seed + player deltas — not full chunk arrays unless required. proc_gen_seed_history.gd.

Godot 4.7

Path3D snap-to-colliders for spline roads/rivers on terrain colliders.