Quake In 13kb Of Javascript

A 13KB JavaScript build of Quake (“q1 K3”) pulls off a full FPS experience—textures, sounds, music, weapons, enemies, and two classic-style maps—by generating most assets in code and aggressively compressing both data and logic. The core takeaway isn’t just nostalgia for the 1996 original; it’s a set of practical size-golf techniques that make a complex 3D game feasible inside the JS13k constraint, where the final submission must fit in a 13KB zipped package.

Instead of shipping pre-made art, the project generates its 31 textures on the fly using a tiny canvas-based texture DSL. Early attempts relied on external PNG textures, but that immediately blew the budget (about 150KB just for textures). The solution was to build a miniature “texture library” with only a handful of drawing primitives—embossed rectangles and grids, noise, and text—then compose those primitives to create grunge-like materials for grass, sky, water, and more. A custom texture editor lets the author draw one texture onto another (including onto itself), producing a full texture set whose definitions zip to roughly 1.3KB.

Map data follows a similar “store less, compute smarter” philosophy. The famous E1M1 layout is represented using axis-aligned bounding blocks (AABBs). That choice sacrifices slopes and fine detail—making the world look more like Minecraft than original Quake—but it slashes geometry storage and simplifies collision math. Collision then becomes tractable through a bitmapped occupancy grid (128×128 cells), so collision checks reduce to looking up which grid cells an entity’s bounding box overlaps, then resolving movement direction-by-direction to allow sliding along walls and floors.

Models and animations are also compressed with Quake-like reuse. Only a few animated model types exist (a basic humanoid, a dog, and a torch), and enemies are created by scaling/stretching the same base geometry and swapping textures. Animated frames are stored compactly, and vertex positions use bit-level packing to improve zip behavior. Geometry is further trimmed by removing unseen faces; even the Quake logo on the title screen is optimized by stripping most sides.

Audio and music are handled with size-first tooling. Music leans on a heavily modified tracker (Sonitent X / ATT-style approach), with oscillator lookup tables generated at startup and music stored in flat arrays rather than JSON objects. Sound effects use a simple spatial audio model: distance and angle to the camera drive volume and stereo panning. The result is a moody, minimalist soundtrack that compresses well, plus spatialized effects that still fit the budget.

All assets and data are packed to leave room for the engine. Two levels total 563 blocks and 188 entities, with level data around 4.5KB uncompressed (3.2KB zipped). Models and textures together land in the low single-digit kilobytes, and the entire game—including unpacking, rendering, physics, AI hooks, and gameplay logic—fits by using minification, zip-friendly data ordering, and an extra compression step via a JavaScript packer (“Road Roller”) that effectively frees about 1.2KB.

The broader message is that “game development” inside JS13k becomes less about authoring everything by hand and more about generating data, choosing representations that compress well, and building tiny tools that provide fast feedback. The payoff is a surprisingly faithful Quake-like experience delivered under extreme constraints—proving that careful engineering can beat the size limit without turning the game into a toy.