Keystone Lite — Free Modular Building Generator (Unreal Engine Plugin)
Free building generator for Unreal.Keystone Lite builds game-ready 3D buildings — walls, floors, roofs, approximate interiors — right in the Unreal Editor. Pick one of three starter presets or draw a footprint on a true-to-scale 2D canvas, then bake to Nanite static meshes with collision that you own outright. No subscription, no credits, no AI required.What you get, free Presets — House, L-Shape, and Gable Cottage, one click each. Sketch — draw the footprint on a true-to-scale 2D canvas (snapping, ortho, real Unreal units); place doors, windows, and interior walls. Parametric editing — tune the building's parameters and inspect the building file. Bake to Nanite static meshes + collision — drop the result straight into your level; you own the mesh. The same deterministic, test-covered geometry core that powers the full Keystone — just a focused free slice of it.Upgrade to Keystone — Building Generator for: Draft from Text & Draft from Image (bring-your-own-key AI, or local Ollama) — describe a building or turn a floor-plan image into one. All eight presets (+ Castle, Setback Tower, Log Cabin, Round Tower) and multi-volume composition (castles, towers, wings). Kit Mode — tile your own modular meshes onto walls and floors. The full detailing toolkit — log-cabin / timber styles, detail bands, crenellations, arcs / round towers, stylize. Import / export building files (JSON). Who it's forIndie devs, students, and hobbyists who want to go from an idea to a game-ready building in minutes — for free — and upgrade when they need AI input, castles & towers, or their own mesh kits.A note on interiorsKeystone drafts approximate interiors (floors, ceilings, interior walls, openings) — ideal for blockout, exteriors, and mid-ground buildings.Requirements & dependencies Engine versions: UE 5.3, 5.4, 5.5, 5.6, 5.7, 5.8 — a separate build per version (download the one matching your engine). Platform: Windows (Win64) editor tool; baked StaticMeshes work on any target platform. Engine plugin (required, auto-enabled): Unreal's built-in Geometry Scripting (ships with Unreal) — used to generate and bake the building meshes. No other plugin is required. No third-party or user-made plugin dependencies. Keystone Lite ships without any AI features. Created with AI (disclosure)Keystone Lite's geometry is generated by a deterministic procedural engine — not by generative AI. Keystone Lite includes no AI features at all (the optional AI text/image drafting lives only in the full Keystone, and is bring-your-own-key). No AI-generated meshes or assets are included. Some of the plugin's source code and this listing's marketing materials were produced with AI assistance.Support Support: https://mythiclemon.com Full version: Keystone — Building Generator. Built and maintained by MythicLemon.
Get it → mythiclemon.gumroad.com