regionseed

Regionseed is a numeric value used to seed a pseudorandom number generator for a specific geographical or logical region within a procedurally generated world. It ensures that the content within that region—such as terrain, biomes, resources, and placements—remains deterministic and repeatable across sessions and platforms when the same seed and global parameters are used.

In practice, regionseed is typically derived from a region’s coordinates combined with a global world seed through a hash function or similar mixing operation. For example, regionSeed = hash(regionX, regionY, worldSeed). That seed is then supplied to region-specific RNGs or noise generators to drive feature placement, elevation, climate, and object distribution. This approach enables on-demand generation of individual regions without recomputing the entire world.

Regionseed supports modular and consistent world-building. It allows multiple regions to be generated independently while maintaining coherence where regions touch, and it facilitates reproducible multiplayer experiences where clients independently produce the same region from the same seed. Some systems use regionseed to seed separate subsystems (e.g., climate, vegetation) to preserve independence among aspects of generation.

Common techniques include seeding a per-region RNG with regionseed, feeding regionseed into layered noise functions, and deriving additional seeds for specific systems. Practical considerations include ensuring a sufficiently large and well-distributed seed space to avoid correlations, choosing robust hashing, and guarding against unwanted global seed leakage or cross-region dependencies. Regionseed is a foundational concept in procedural generation, aiding reproducibility, scalability, and debugging in tiled or partitioned worlds.