t1k:designer:systems:procedural-generation

Keywords: generation, PCG, procedural generation, random

How to invoke

/t1k:designer:systems:procedural-generation

BSP (Binary Space Partitioning): split rect recursively → rooms at leaves → corridors between
Drunkard’s Walk: random walk carves passages → organic cave-like layouts
Room-and-corridor: place N rooms (no overlap) → connect with L-shaped corridors
Cellular automata: random fill → smooth passes (alive if 5+ neighbors) → natural caves
WFC (Wave Function Collapse): tiles with adjacency rules → guaranteed valid layouts
Prefab stitching: pre-designed rooms + procedural connections (Dead Cells approach)
Validation: A* from start→exit, all rooms reachable, key items on longest path

→ See references/dungeon-generation.md for algorithm decision tree, BSP implementation, validation

Affix system: prefix + base + suffix (e.g. “Cruel Longsword of Fire”)
Pool weighting: Common 60% / Rare 25% / Epic 10% / Legendary 5%
Stat rolling: base_value × (1 + random(0, tier_bonus)) × rarity_multiplier
Smart loot: 30% bias toward player’s equipped slot type, 70% random
Seed formula: item_seed = hash(entity_id, encounter_index, world_seed) → reproducible

→ See references/item-generation.md for affix pools, stat ranges, anti-duplicate patterns

Floor template: 6-10 rooms → elite room → shop → 6-10 rooms → boss
Room type mix: combat 60% / treasure 15% / event/choice 15% / shop 10%
Difficulty scaling: enemy_hp × (1 + floor × 0.4), enemy_atk × (1 + floor × 0.25)
Item pacing: 1 item per 2-3 rooms, guaranteed rare per floor, shop every 8-12 rooms
Run length: 30-45 min (casual), 60-90 min (hardcore)
Meta-progression: permanent unlocks between runs (new items in pool, starting bonuses)

→ See references/roguelike-structure.md for floor templates, meta-progression, risk/reward rooms

Use Case	Algorithm
Natural caves	Cellular automata
Structured dungeons	BSP or room-and-corridor
Organic passages	Drunkard’s Walk
Tile-based valid layouts	Wave Function Collapse
Handcrafted + procedural	Prefab stitching
Item stats	Weighted affix pool + seed hash

#	Anti-Pattern	Problem	Fix
1	Pure random placement	Unsolvable maps, isolated rooms	Validate with A* after generation
2	No seed system	Non-reproducible bugs	`hash(entity_id, encounter, world_seed)`
3	Stat ranges too wide	Useless low-roll items	Floor = base_value × 0.8 minimum
4	Monotonous output	Feels generated, not designed	Mix prefab rooms with procedural connections
5	No pity in loot rolls	Legendary drought → quit	Guaranteed rare escalation per floor

rpg-game-design — Item rarity tiers, loot tables, power budgets
game-economy-design — Loot drop rates as economy faucets
engine inventory skills (auto-activated via registry) — procedural item integration
puzzle-game-design — Procedural puzzle generation patterns
engine scene skills (auto-activated via registry) — arena tile/geometry generation

File	Coverage
`references/dungeon-generation.md`	BSP, cellular automata, WFC, validation
`references/item-generation.md`	Affix pools, stat rolling, smart loot, seeds
`references/roguelike-structure.md`	Floor templates, room types, meta-progression

Seeded reproducibility is a contract — if any RNG call is unseeded, replays diverge silently.
Wave-function-collapse outputs need playability validators — beautiful unsolvable rooms are a worse failure than ugly playable ones.
Affix rolling distributions need explicit min-quality floors — without one, the bottom 10% of items are de facto trash and feel like bugs.