jasonkneen/tiny-world-builder

Tiny World Builder is a browser-based 3D world editor that lets you sculpt terrain, place buildings and objects, and fly through the worlds you create. Think of it as a Minecraft-like creative tool, but focused on building tiny dioramas, cliffs, rivers, houses, farms, roads, and animals, that you can explore from any angle and share with others. You start with a grid and click cells to place terrain (grass, water, stone, sand, snow, lava) or objects (houses, trees, fences, crops, animals). The editor is smart about adjacency: place two path cells next to each other and they join into a road, place houses near each other and they merge into larger building shapes, put water near land and you get banks and foam. You can sculpt terrain by raising or lowering cells, paint surfaces, switch between isometric and perspective camera views, and stack objects up to eight levels high. Worlds save locally in your browser, and you can export or share them. The project also includes a vehicle system with working traffic AI. You can spawn cars on roads, give them destinations, and watch them navigate, they reroute around obstacles, yield to each other, and stop if a road is fully blocked. There's even a seeded demo mode that generates a city grid with arterial roads, bridges, and cul-de-sacs, then populates it with delivery vehicles driving along routes. The audience here is anyone who wants to prototype or visualize a small 3D world without setting up a game engine. A game designer could mock up a level layout, a founder could demo a spatial concept to investors, or a hobbyist could just build something charming and share a link. Technically, it's a single JavaScript file using the Three.js 3D library, with everything self-hosted, no external CDN dependencies. It deploys as a static site on platforms like Vercel or Netlify. The README is notably detailed about its internal architecture, which is unusual for a creative tool and suggests it's built with extensibility in mind.