ROADLINE '91 – a palette-indexed polygon racer for the browser

Screenshots

Title screen with palette color cycling

Car and race setup screen — Four fictional cars, each with its own character

Cockpit view on the coast road — Cockpit with working gauges and a rear-view mirror

Cliff road with a lighthouse at sunset — Sea cliff and lighthouse at sunset

Snowy mountain pass — Mountain pass with hairpins above a drop

Red rock canyon — Winding red-rock canyon

Redwood forest in the rain — Rain: wipers, drops, wet asphalt, less grip

Suburbs at night with street lamps — Night: dithered headlight wedge and street lamps

Police car overtaking on a bridge — Radar trap, chase and radar detector

Dot-matrix printed traffic citation — A citation printed like a dot-matrix printout

Desert road in fog — Fog done with dithering, never smooth blending

Replay with the top camera — Replay of the last minute with four cameras

Features

About 40 km route from the coast over a snowy pass, through a canyon, redwoods, suburbs, a lake and the highway to the desert – six sections ending at gas stations, two branches including a gravel shortcut.
Four fictional cars: Vektor GT (all-rounder), Aurora MR (fastest, nervous), Breeze R (best in corners), Kestrel S (stable, good in the rain).
Arcade-sim physics: torque curves, five gears with automatic or manual shifting, a bicycle tyre model with slides you can catch.
Two-way traffic, an AI rival that stops at the stations too, police with radars, chases and citations – three stops end the race.
Day, sunset and night; rain and fog; outside cameras; a replay of the last 60 seconds.
Original FM-synthesis music and sound effects generated with the Web Audio API: rpm-driven engine, siren with Doppler shift.
Records, key remapping, volume settings, touch controls, 640×400 enhanced mode and a 15 FPS historical mode (F3).

Controls

Action	Keyboard	Gamepad
Throttle / brake	↑ / ↓ or W / S	RT / LT
Steer	← → or A D	Left stick, D-pad
Gear up / down (manual)	E / Q	RB / LB
Camera / look back	C / V	Y / R3
Replay / horn	R / H	Back / L3
Pause	Esc or P	Start
Mute	M

Driving keys can be remapped in CONTROLS (title and pause menus). On phones on-screen buttons appear after the first touch.

How it is made

The world is rendered into an R8UI 320×200 texture that holds palette indices, not colors. Flat shading, fog and lighting are all quantized with a 4×4 Bayer matrix in index space; a final pass looks the indices up in a 256-entry palette texture and scales the picture to a 4:3 letterbox with nearest-neighbour sampling. Models, sounds, music and the font are defined in code – there are no image or audio files. The whole game builds into a single HTML file of about 420 KB.