Noclip: Fly Through the Maps of Classic Video Games in Your Browser

Noclip takes the levels of games you played twenty years ago, loads them into your browser, and then removes the walls. Not the walls visually. The walls conceptually. You get a camera that goes anywhere: through the floor of Peach’s castle, out past the skybox, into the empty space behind a mountain that only ever existed as a painted backdrop.

It is named after the developer console command that switches off collision detection, and it does exactly what that command always did, which is turn a game into a diorama.

What is Noclip?

The project is largely the work of Jasper St. Pierre, a graphics programmer who has spent years reverse-engineering the file formats of old console games and writing WebGL renderers for them. Other contributors have added engines over time. It is open source, it is free, and it runs entirely in a browser tab with no plugin and no install.

That is harder than it sounds. Every console generation had its own rendering quirks, and much of what made these games look the way they did was hardware-specific trickery: texture filtering, fixed-function shading, the fog and dithering tricks used to hide draw distance. Rendering the geometry is the easy part. Rendering it so it looks right, the way it looked on a CRT in 2002, is the actual work, and Noclip is unusually good at it.

What you get from that fidelity is a kind of architectural tour. Once you can fly, you start noticing how these worlds were built. Rooms that appear to be adjacent turn out to be miles apart, connected by a loading corridor. Entire towns are two-dimensional paintings glued to a wall. Characters standing in a cutscene are posed on a floating platform in a void off to one side. The illusions were designed to be viewed from one specific angle, and Noclip lets you stand at every other angle.

There is also a preservation argument here, and it is not a small one. These are cultural artifacts locked inside hardware that is aging out. Being able to open a level in a browser and look at how it was constructed is genuinely useful to anyone studying game design, level design or the history of real-time graphics, and it is the kind of access that formal archives have been slow to provide.

Mostly, though, it is just an extraordinary hit of nostalgia delivered from an impossible vantage point. You know these places. You have never seen them from above.

What can you do with Noclip?

• Pick a game and a map. The scene browser lists the supported titles, each broken down into its individual levels and areas.
• Fly anywhere. WASD and the mouse, with keys for vertical movement and a speed modifier. No collision, no boundaries, no invisible walls.
• Look behind the scenery. Get outside the level and see the hollow backs of buildings, the unfinished geometry, the tricks that were never meant to be visible.
• Toggle rendering layers. Most scenes let you turn off elements like fog, water, skyboxes or specific object groups, which is how you find what was hidden underneath.
• Change camera modes. Switch between free-fly and orbit-style controls depending on whether you are exploring or framing a shot.
• Share an exact viewpoint. Camera positions can be encoded into the URL, so you can send someone a link that opens at the precise angle you found.
• Study level design for real. Measure sightlines, look at how paths funnel players, see where the designers put their landmarks.

Tips to get the most out of it

Slow the camera down. The default flying speed is tuned for crossing a map quickly and is far too fast for looking at anything. Hold the slow modifier when you get close to something, or you will overshoot every detail in the level.

Start with a game you know intimately. The whole pleasure of Noclip is the gap between your memory of a place and its actual layout. That gap only exists for maps you have walked through a hundred times as a kid.

Go straight up. The single best move on the site. Rise until the whole level is below you and see the shape of a world you only ever experienced from ground level.

Open the scene options panel. Nearly every game has custom toggles buried in there. Some switch time of day, some strip out object layers, some expose debug views.

Use a desktop with a real mouse. It technically works on other setups, but free-look flying wants a mouse and a keyboard, and heavier scenes want a machine that can push some polygons.

Give a scene a moment to load. Some maps are large and stream a lot of data. A black screen for a few seconds usually means it is working, not broken.

If you like Noclip, also try…

• Bruno Simon: another demonstration of what a browser can render in real time, this time as a drivable portfolio.
• Floor796: an endlessly expanding animated scene packed with things to find, best explored by wandering.
• Zoomquilt: an infinite painting that falls into itself, for when you want to move through a space with no destination.
• Random Street View: the same aimless exploring instinct, pointed at the real world instead.

Plenty more browser-based rabbit holes in Entertainment & Fun.