Real Underwater Worlds — Biome Generator & Rendering

Generate complete underwater worlds from 12 biome presets: seabed, rocks, corals, plants, fish and bubbles, rendered with physically based water. Built-in, URP and HDRP in one package.

Unity 6000.3.21f1 or newer 6000.3 releases. Built-in Render Pipeline, Universal RP 17.3 and High Definition RP 17.3 in one package; Install configures the active pipeline and converts the package's materials (URP Lit, HDRP Lit or Standard).

Content: 98 models (21 rocks, 26 corals, 25 props, 26 fish and jellyfish), 2,849 to 49,746 triangles each (median 9,817; about 1.2 million in total). Textures: PNG BaseColor and Normal at 2048 (57 models) or 1024 (41 models), MetallicSmoothness at 1024. 111 prefabs, 13 procedural plant families, bubble column, stream and cloud prefabs.

12 biome presets and 12 demo scenes, generated on your machine (about 1 to 20 seconds per scene); generated meshes, materials and prefabs are saved next to the scene.

Generator: procedural sea floor (chunked meshes, grid spacing 0.1 to 10 m, optional colliders and ceilings), rule-based distribution with Undo, pinning, per-group regeneration and an interactive box preview. Fish and jellyfish schools animated in the vertex shader; plants and soft content sway with the current.

Underwater effect: URP renderer feature, HDRP custom post-process, Built-in camera components; 76 Volume controls per water profile, 12 stock profiles per pipeline. Anti-aliasing: SMAA (no MSAA in URP and Built-in).

Demo flight: Input System package or Input Manager. Editor interface in English and Russian. Menus under Window > Real Underwater Worlds.

No third-party packages and no Asset Store dependencies. Documentation: manual in Markdown and HTML, quick start, changelog.

Real Underwater Worlds builds complete underwater scenes in Unity and renders them as if the camera were really in the water. Pick a biome preset, press Generate, and in seconds you have a seabed with rocks, corals, plants, fish, bubbles, a water surface and matching light - and every part of it stays editable.

FROM A PRESET TO A LIVING SCENE IN ONE CLICK

One Setup window builds the whole world in the order a world is built: World, Sea floor, Distribution, Fauna, Effects, Physics and Light. Twelve biome presets are ready to go - Ocean, Tropical Lagoon, Lake, Swimming Pool, Swamp, Harbour, Cave, Shallows, Deep Dive, Ice Water, Stylized Ocean and Stylized Lagoon - each with a demo scene. Change a setting and regenerate only that group, pin the objects you like so they survive every regeneration, and step back with Undo. The interface speaks English and Russian.

TRY IT AS BOXES BEFORE YOU GENERATE

Interactive preview mode draws coloured boxes where objects would go - the same engine and seed as a real Generate - and re-samples every change within a second or two. Tune coral density, rock sizes, kelp, grass patches and fish schools in the preview, then generate once.

A SEABED THAT PUTS THINGS WHERE THEY BELONG

The procedural sea floor has relief, ridges, sandy passages and optional cave and ice ceilings with colliders - or use your own mesh or Terrain. Everything that stands on it is a group with its own rules: uniform, clustered or patterned distribution, density per square metre, density masks, depth and slope bands, burial, surface alignment, obstacles and support, so plants grow on rocks and fish avoid the floor. The library holds more than 100 prefabs and 13 procedural plant families - kelp, sea grass, pondweed, reeds, lilies and more - grown in code and tinted per group.

LIFE AND MOTION

Fish and jellyfish swim in schools sized by their body length, with a tail beat that follows their speed. Plants sway in the current, bubbles rise in columns, streams and clouds and pop at the real water surface, and one world-motion dial sets how lively the whole biome is.

WATER THAT LOOKS LIKE WATER

The underwater look is physically based: Beer-Lambert absorption that turns distance blue-green, turbidity and silt, depth darkening, Snell's window with a mirror surface beyond it, caustics projected from the refracted sun, light shafts, a half-in half-out waterline, wet lens after surfacing, and Scattered Light - the sky through Snell's window and the light the seabed bounces into the shade, traced live around the camera. Blow-out protection keeps a lit rock at the lens from burning to white. Each biome owns a water profile with 76 controls on a Volume; your edits survive Generate and package updates, and Save As keeps a look of your own.

ONE PACKAGE, THREE PIPELINES

The same package runs in the Built-in Render Pipeline, URP 17.3 and HDRP 17.3. Install sets up the active pipeline - the URP renderer feature, the HDRP custom post-process or the Built-in camera components - converts the package's materials, and creates the stock water profiles. Scene checks list anything that spoils the water (post-processing, MSAA, HDR, colour space, shadows) with a Fix button each.

QUICK START

1. Import the package and open Window > Real Underwater Worlds > Setup.

2. Press Install.

3. Save your scene, pick a biome preset and press Generate.

4. Press Play and fly with W A S D, Q / E and the right mouse button.

The demo scenes ship ungenerated to keep the download small: open one, press Generate, then Play.

WHAT YOU GET

The Setup window with Generate, Cancel, Clear, per-group regeneration, pinning, Undo, the interactive preview and Scene checks.

12 biome presets and 12 demo scenes.

98 models - 21 rocks, 26 corals, 25 props and 26 fish and jellyfish - and 111 prefabs, plus 13 procedural plant families and bubble column, stream and cloud prefabs.

The underwater effect for URP, HDRP and Built-in with 12 stock water profiles, and water surface components for your own water (plane, volume, heightmap or a height function in code).

A demo flight camera that works with the Input System package and the Input Manager, a scripting API for the water state and the profiles.

A manual (Markdown and HTML), a quick start and a changelog.

REQUIREMENTS AND NOTES

Unity 6000.3.21f1 or a newer 6000.3 release. Built-in, URP 17.3 or HDRP 17.3; custom render pipelines are not supported. Linear colour space is recommended. Perspective cameras; one water body is active at a time. The looks are tuned in URP; Built-in and HDRP come within about 0.2 stop, except the upward view in HDRP, which shows your scene's HDRI sky. In HDRP plants and animals do not bend (static double-sided Lit), and bubble refraction and caustics that dim in the sun's shadow are URP only. The Built-in camera must render in HDR for Bloom and tonemapping.

AI-generated models: the 98 models of rocks, corals, props and fish were generated with AI 3D generators from AI-generated concept images and then prepared by us for Unity - see the AI disclosure. The plants, seabed, water rendering, bubbles, fish motion and all code are our own work.