Open World Environment is a procedural open-world toolkit for Unreal Engine 5.7, written entirely in C++. The world is generated at runtime from a seed: an endless grid of streaming terrain chunks built on worker threads from layered noise, with continents, hills, ridged mountains, rivers carved into the lowlands, roads that flatten the ground, and eleven biomes decided by altitude, temperature and moisture. Four levels of detail with skirts keep seams invisible, and trees, rocks, cacti and grass are scattered per biome into hierarchical instanced meshes.

A full day-night cycle drives the sun, moon, sky atmosphere, a procedural cloud layer and a star dome. Weather follows the local climate: rain, storms with lightning, fog and snow, with wet ground and snow piling up on the terrain material. Water, wildlife that wanders and flees, settlements with glowing waypoint beacons, a third-person explorer with sprint and swimming, and an amphibious arcade buggy with headlights and a chase camera are included.

Sound is synthesised in C++ (wind, rain, water, birds, crickets, engine, footsteps, thunder), so there are no audio files.

On the interface side you get a canvas HUD with compass, minimap, speedometer and toasts, a zoomable fast-travel map, a world-seed screen with a live preview, settings, time and weather menus, a performance overlay, Enhanced Input created at runtime (keyboard, mouse and gamepad) and save games. 426 assertions across 15 Unreal Automation tests ship with it. There is no external art: people, animals and vehicles are built from engine primitives, so you can swap in your own meshes at clearly marked points.