Q3Edit: A Quake 3 Map Editor That Runs Entirely in the Browser

Someone has gone and done the thing that every old-school FPS modder has dreamed of: a full Quake III Arena map editor that runs in a browser tab. No local tools, no Wine hacks, no fighting with 20-year-old installers. Q3Edit is a TypeScript + WebGL2 editor that opens real .map files, lets you edit brushes, patches, entities, and terrain, then compiles the BSP using id Software's original q3map — compiled to WebAssembly — and launches the result in a browser-native ioquake3 build.

What's Actually Under the Hood

The editor presents a Radiant-style four-view UI (top, front, side, 3D perspective), which is the standard layout anyone who's touched a Quake editor will recognize. It supports CSG operations, terrain editing, and the full entity system. The BSP compiler is the real deal — the same q3map that id Software shipped, ported to WASM. That means the compiled maps are bit-for-bit compatible with original Quake III and its open-source sibling OpenArena.

One click compiles your map and loads it into ioquake3, also compiled to WebAssembly. You can play your map immediately, no separate game client needed. The project ships with OpenArena assets, so you don't need to provide any game files to get started — though it can load your own .pk3 archives if you have them.

Why This Matters

This isn't a toy. The entire pipeline — editing, compiling, testing — happens in the browser with no server-side processing. It's a demonstration of how far WebAssembly and modern WebGL have come: you can now run a full game engine and its toolchain in a sandbox that loads in seconds. For developers working on web-based tooling, this is a reference point for how to port complex C/C++ codebases to the browser without sacrificing performance.

The source code is available, and the project is built on top of ioquake3, which is the community-maintained, GPL-licensed fork of the Quake III engine. If you've ever wanted to teach someone how BSP compilation works, or just want to edit a Quake map on a Chromebook, this is your tool.