Every island you see below is built out of Parts at runtime. No Roblox Terrain, no meshes, no imported assets. Press Play and you get a fresh island: beaches, terraced hills, mountains, trees, rocks and grass, all generated from scratch.
The place is uncopylocked. Wait a few seconds for the terrain to finish generating upon joining the game.
(ISLAND TERRAIN GENERATOR | Play on Roblox)
The default island: sandy beach ring, forested interior, terraced hillsides.
Customizable biomes: 4 built-in examples
What it does
- Procedural terrain. fBm noise with domain warping, plus explicitly placed mountain peaks so every island gets a readable silhouette instead of a lumpy blanket.
- Minecraft-style beaches. Coastal tiles are classified per tile: low and gentle ones become flat sand, tall or steep ones become stone shore.
- Terraced hillsides. Height steps between tiles get filled with “bands”, so hills read as terraced ledges rather than sheer walls.
- Crumbly dirt. Exposed dirt faces get chunky cubes bolted onto them via BSP slicing, so dirt looks eroded instead of like a clean box.
- Mottled ground. Thin lighter overlays scattered on grass and sand. Cheapest trick in the kit, does the most work.
- Trees, rocks and grass. Rocks rejection-sample their spots so they don’t intersect trunks. Grass is client-side only (see below).
- Multiple islands.
Island.generateAt(position, overrides)builds an island anywhere, with its own biome, size and settings. Archipelagos in a few lines.
Everything is customizable
There’s one file, IslandKit.Config, and it’s the only file most people will ever touch. It’s plain values with comments on every one:
Config.seed = 12345 -- same island every run
Config.island.radius = 600 -- bigger island
Config.peaks.height = {80, 160} -- real mountains
Config.biome = "Snowy" -- reskin the whole world
Config.foliage.drawDistance = 70 -- the big perf lever
Config.dirtify.enabled = false -- cheaper, cleaner terrain
Grass colors, dirt colors, beach width, sand shade, patch density, tree and rock density, grid size, noise, the sea. It’s all in there.
Biomes are pure data. Duplicate Biomes.Forest, change the colors, point Config.biome at it. There’s no code in a biome file, so you can’t break the generator by writing one. Ships with Forest, Desert, Snowy and Volcanic.
Props are drag-and-drop. Drop Models into IslandKit.Props.Trees / .Rocks / .Foliage and they get scattered automatically, no code changes. (One rule: a prop’s pivot must sit at its base.)
Many islands
local Island = require(ReplicatedStorage.IslandKit.Modules.IslandGenerator)
Island.generateAt(Vector3.new(0, 0, 0), {
island = { radius = 350 },
spawn = { placeSpawnLocation = true }, -- players start here
})
Island.generateAt(Vector3.new(1300, 0, 400), { biome = "Snowy", island = { radius = 200 } })
Island.generateAt(Vector3.new(-1100, 0, 900), { biome = "Volcanic", island = { radius = 300 } })
Every Config field works per island, so islands in one world can be completely different. They share a single sea that grows to reach the furthest one. Islands can be generated at any time, mid-round, procedurally, or in response to a player, and the foliage system picks up new ones on its own. There’s also getIslands(), clearAll() and wouldOverlap() for placing them procedurally.
A note on performance
Ground cover is normally what causes lag: tens of thousands of grass tufts is not something you can replicate or render. So the grass is never replicated. Each client derives the identical layout independently by seeding an RNG from each grass cap’s world position, then only instantiates the foliage near its own camera, pooling and recycling models as you walk. Everyone sees the same grass, and it costs zero network traffic. Cost scales with draw distance, not island size.
Generation itself is spread across frames, so the server never hitches while building. A default island takes about 8 seconds.
Structure
ReplicatedStorage.IslandKit
├── Config ← the only file you need to open
├── README ← full docs
├── Biomes/ Forest, Desert, Snowy, Volcanic
├── Modules/ Noise, HeightField, Tiler, Builder, Dirtify, Patches, Scatter, IslandGenerator
└── Props/ Trees, Rocks, Foliage
Tiler decides, Builder builds. To change the shape of the island you never need to open Builder. To change how it looks you never need to open Tiler.
Full documentation is in the README
IslandKit.README covers all of it: setup, every config option, writing your own biome, adding props, the module architecture, performance levers, runtime regeneration, and how to build mining, painting or placement on top (every terrain part is tagged and named by role).
Take it, tear it apart, use it in whatever you’re making. If you build something with it I’d love to see it!