Level Designer - Runtime Level Editor

Level Designer gives players (or your own level-design team) an in-game editor for arranging prefab modules, like walls, props, and set pieces, with three snapping modes (joint, grid, and collider-based) instead of relying on manual placement or a full custom editor build.

Modules are organized automatically from a Resources folder into a generated menu, with bulk thumbnail generation and JSON save/load for finished layouts. A SciFi sample set and playable scene demonstrate the full loop from placement to reloading a saved level in-game.

Fits games that ship a level editor as a player-facing feature, such as sandbox or building games, as well as internal level-design teams who want a faster, script-free way to block out levels from a shared prefab library instead of hand-placing every piece in the Scene view.

How it works

Open the LevelDesigner scene and press Play. Drag modules from the generated menu onto the floor and save from the left menu. Levels are saved as JSON in Unity's persistent data folder.

A saved level can be loaded back into your own game three ways: from code (the LevelDesigner_PlayMode scene and DemoPlayMode.cs show how), with the LevelReader prefab and its Load By Name component (built in the Editor ahead of time, at Start, or on demand with LevelLoadByName.LoadFile(fileName)), or by exporting to FBX in the Editor through Unity's FBX Exporter package.

Building your own modules

An Editor window, added in version 3.0, manages categories, module details, and thumbnails, and can generate module prefabs from 3D models selected in the Hierarchy. Each prefab then gets a collider sized to fit and FJoint objects on every side that should snap to another module. On the Module component, Is Ground Tile marks floor pieces and Snap On Grid enables grid snapping.

What's included

• Three snapping modes: joint, grid, and collider-based
• Automatic module menu generation with bulk thumbnails
• JSON save/load, keyboard move/rotate/scale controls
• Free-included Touch Camera Lite (perspective and top-down modes)
• SciFi sample set and a PlayMode scene for loading levels in-game
• Full source code, WebGL, Built-in/URP/HDRP support

Compatibility

The Asset Store listing gives Unity 2021.3.30 as the minimum version and lists the Built-in Render Pipeline, URP, HDRP, and custom render pipelines as compatible. Version 3.0.1 (November 7th 2024) fixed the module Editor window in Unity 2022 and later. Two notes from the manual: the thumbnail generator doesn't work with HDRP, so generate thumbnails under the Built-in pipeline or make them by hand; and the bundled Newtonsoft.Json build is modified to work with IL2CPP, so keep it to avoid save/load errors in IL2CPP builds.

Planned: full mobile touch support (camera controls are already mobile-ready), online saving, and a VR demo.

Common questions

Do I need to manually register each prefab module? No. Modules are organized automatically from a Resources folder into a generated menu, so adding a new piece is just a matter of dropping it into the right folder.

Can players save and reload their own levels? Yes. Layouts save and load as JSON, so player-built levels persist between sessions.

Is mobile touch input supported yet? Camera controls are already mobile-ready via the bundled Touch Camera Lite; full mobile touch support for the editor itself is planned but not yet shipped.

Online manual