Interstellar

Interstellar is a top-down space combat game for the browser — inertial flight, energy warfare, and zone chat, built from scratch with no engine and no dependencies: sprite-shaded ships with bloom and particles, synthesized audio, a 12-ship hangar (the 8 fleet hulls plus the NOVA class), and real online multiplayer via a zero-dependency Node server.

The game is built around dueling and squad dogfights: fast kill-trade loops, hit-confirm feedback on every landed shot, kill streaks and multikill callouts, and matches short enough to always want one more.

Game modes

Mode	What it is
Duel (1 on the title screen)	You vs the Ace — a high-skill AI duelist. First to 5. Respawns are near-instant, facing each other across the central arena. Your lifetime W–L record is kept.
Squad Battle (2 or Enter)	3v3 team dogfight vs bots — blue vs red, no friendly fire, anchored team spawns, wingmen that hunt with you. First to 15. Every ship keeps its own identity color — team reads from the blue/red halo ring, nameplates, and radar.
The Zone (3)	The MMO layer: a persistent living world across a 3×3 grid of quadrants, where four squads wage territorial war. Pick a squad (or fly freelance), salvage credits, buy permanent upgrades. No match, no clock — the zone fights on while you're away and remembers everything.

All of it plays out across endless space: a 7×7 lattice of quadrants — 49 full classic-zone sectors, 115 kilometres corner to corner, minutes of hypersonic flight to cross. The tile field is stored sparsely (space is ~99.5% empty, so only chunks containing built structure exist in memory — 3.5MB where a dense map would take 49MB), which makes the world size nearly free; the radar samples it live. The center quadrant is the contested core; the four corners belong to the squads; everything between is frontier, charted by bearing and grid reference ("ENTERING THE SOUTHWEST FRONTIER · B6"). Most quadrants hold a depot or twin outposts worth raiding, eight asteroid belts sweep the deep, and two hundred derelicts drift as landmarks.

Squad territory. Four squads — the Crimson Pact, Cobalt Combine, Ember Syndicate, and Violet Dominion — each hold a corner quadrant, anchored by a triple-walled fortress with a mothership in the keep: a capital-ship anchor whose shadow recharges its own squad 2.4× faster, making home base a real place to rearm and regroup. A faction gate outside each fortress jumps squad ships straight to the core's rim, so territory means both a safe rear and a lane to the war. Pick your squad (or fly freelance) when you enter the Zone; bot squads fight the four-way war with or without you, and squad members respawn under their mothership.

Territorial war. Squads capture quadrants: sole majority presence in a frontier quadrant for 45 accumulated seconds flips it — the chart updates ("D2 · CRIMSON HELD"), the capture is announced sector-wide, participants earn credits, and held ground recharges its holders' hulls 30% faster. Home quadrants never fall, the core is forever contested, and no law reaches the Dead Zone.

Your wing. Fly for a squad and a named wing (TALON, HALO, CINDER, SHADE) forms on you — two squadmates who hold formation off your stern, hunt what you hunt, and fall on whoever falls on you.

Capital ships. Each squad's carrier is a 300-metre hull rendered through the same heightmap → albedo → per-pixel lighting bake as the fighters, so it reads as the same fleet at ten times the scale — and it is under way, patrolling its quadrant rather than parked. Fly into its shadow and press G to dock: you ride along inside the bay, untouchable, refitting at four times the normal rate, until you press G to launch. Its course is a closed-form epicycle from the world seed, so every peer sees the carrier in the same place with no position netcode at all.

Boss hunts. Three classes of hostile capital prowl the frontier, and they range from soloable to a squad wall:

Boss	Where	Hull	Payout
◆ Reaver	open frontier (×3)	5,200	¢850 · ◆1
◆◆ Leviathan	the Maelstrom	21,000	¢2,600 · ◆2
◆◆◆ Dreadnought	the Dead Zone	54,000	¢7,200 · ◆4

They fly their own patrols, fire batteries of turrets at anything in range (everyone is an enemy), ram like a wall, and shed a cloud of greens when they break up. Get within engagement range and a tiered hull bar takes the top of your screen. Bullets chip them; bombs are how you actually crack one. They respawn at their lair on a timer, so a lair is a place you can farm — if you can take it. Carry a Leviathan Hunt contract and the course pointer aims straight at the nearest living boss.

Contracts. You always carry three, and they complete from what you'd be doing anyway — Hunt, Bounty (marauder heads), Salvage, Scavenge (derelict caches), Recovery (relics), Survey (chart new quadrants), and Conquest (help take ground). Each pays credits and is replaced the moment it's done, so the deep frontier always has a reason to be out there. J opens the board; progress persists with your pilot.

Finding the fight. Every contract drives a course pointer: a gold chevron at the screen edge aiming at the nearest live objective — the boss lair, a marauder, an uncracked cache, an uncharted quadrant — with its distance. V cycles which contract it tracks. For the return leg, T warps you home to your mothership (freelancers ride to the contested core) and Y drops a waypoint beacon you can warp back to — both cost 450 energy on a shared 25-second cooldown, so they're travel, not escape.

A frontier that's inhabited. Two hundred derelict caches drift across the map — quick amber salvage worth credits, respawning, visible on the scanner. Half the zone's ships fly patrol routes over assigned quadrants rather than clustering at the core, so a long burn runs into somebody. The Dead Zone keeps a standing pirate presence, and generated events fire roughly twice as often as the sector's other hazards.

Upgrades, not greens. In the Zone, greens don't grant random powerups — you salvage them for credits (kills pay too: 30 + bounty). Press U for the upgrade bay: Cannons, Bombs, Engines, Reactor, Recharger, MultiFire, Prox Fuse, and Repel/Burst/Rocket racks — ten tracks with escalating prices. Top tiers demand ◆ relics: rare tech cached only in dangerous places — the Maelstrom's heart, the Dead Zone, rival fortress quadrants, and the deep belts. Upgrades are permanent: they survive death and are saved between sessions. Match modes (Duel, Squad, Core) stay classic — pure skill, greens and all.

Finds: the rarity ladder. Layered over the credit economy, modules drop from the things you already fight — derelict caches, marauders, and every boss kill — in four tiers: common green, rare blue, epic purple, legendary orange. A module is a permanent stat package (Afterburner, Capacitor Bank, Recharge Coil, Autoloader, Warhead Pack, Deflector Plate, Prox Trigger, Salvage Scoop); rarity multiplies it and a power roll keeps two drops of the same tier from being identical. You fly three mounts, one per module type — press I for the hold, fit and unfit freely, scrap the rest for credits. The Dreadnought's first drop is always a legendary, and a legendary on the field throws a beacon of light you can see from a fight away.

The Dead Zone. One edge quadrant belongs to nobody and never will: marauder country, relic-rich, storm-scored on the soundtrack. High risk, highest reward.

Generated events force action. On a deterministic timeline (identical for every client, no netcode), the sector throws: asteroid showers that rake a quadrant with streaking rock; marauder raids — pirate packs hostile to everyone, worth fat bounties, whose survivors prowl the sector until somebody collects; and stellar collapse — an 18-second evacuation warning, then a supernova shockwave that expands three kilometres and hits like a freight train. Every event is announced with its chart reference and pulses on the scanner.

The whole map spans a scale where travel matters — a single quadrant is already a former full map: The population concentrates in the mid-sector around the arena, so fights are easy to find, while the enormous frontier beyond is open space for prize runs and long hypersonic chases — the starfield streaks with your speed. The corner radar is a local scanner, not a full-map view: it covers the space around you and shows your position on a lettered 16×16 sector grid (SECTOR H8).

The sector is open space with deliberate architecture — nothing is scattered at random. A citadel ring guards the arena at the heart; six guard stations (concentric forts, cross-armed dock stations, shipyards with rows of hangar berths) sit on the approach radius, so you pass them on every run to the core; three frontier depots wait deep in the black; asteroid belts sweep the sector in navigable arcs; and lone derelicts drift as landmarks. Every installation matters: a third of all greens cache around bases, so stations are supply depots — worth flying to, and worth fighting over.

And somewhere in the frontier churns THE MAELSTROM — a storm of flying rock two kilometres wide that tears hulls on contact ("torn apart by the maelstrom" is a real way to die). Its eye is calm, its interior is rich with greens, and its boundary paints red on your radar. Scattered through normal space, wormholes (purple swirls, on radar too) swallow any ship that strays too close — bots included — and dump it inside the storm; a rim gate leads back toward the citadel. Rock trajectories are closed-form functions of world time, so every client sees identical storms with zero extra netcode — the server just shares its clock.

Encounters are events: when a hostile enters your radar bubble you get a sonar CONTACT ping — target brackets if they're on screen, a bearing chevron with range if they're not — and the adaptive soundtrack surges. Stealth hulls arrive unannounced; that's their job. And when you're alone in the deep, a faint hunt compass points at the nearest hostile with its range, so every trek is aimed at a fight. | Hold the Core (4) | 3v3 objective mode: hold the glowing center ring alone for 3 seconds to score a point. First to 20. Forces the fight into one shared arena. | | Online (O) | Real multiplayer with rounds, MVPs, side swaps, an Elo duel ladder, and persistent pilot stats. MODE=teams (default), MODE=core, or MODE=ffa. |

The feel layer runs in every mode: a hit-confirm tick each time your shot lands, a kill-confirm jingle, DOUBLE KILL / TRIPLE KILL / KILLING FRENZY banners, streak callouts in the feed ("X is on a rampage!"), a killcam that follows your killer while you wait to respawn, and victory / defeat fanfares with instant rematch on Enter.

The competitive spine (online)

• Your callsign is your identity — and it's registered. The first flight under a name mints a random 128-bit token; the client keeps it, the server keeps only its hash, and later joins claiming that name without the token are refused. The server persists every pilot's Elo, duel record, kills/deaths, accuracy, and score in data/players.json (DATA_DIR overrides the location) — shown on the connect screen, in /stats chat, and on the web ladder at http://server:8666/stats.
• Duel ladder: type /duel <name> in chat; they type /accept. Both of you warp to the center arena, first to 5 (any death counts). The zone watches the score line by line, and the result — with Elo changes — is announced to everyone. Disconnecting forfeits.
• Elo badges on nameplates: ☆ at 1275, ★ at 1400, ★★ at 1600.
• Rounds: when a team hits the goal, the round ends with an MVP callout, sides swap, and scores reset. Optional Discord announcements via DISCORD_WEBHOOK=<url>.
• Map votes: /votemap nexus | gauntlet | rings — a majority vote warps the whole zone to a fresh sector of that style, mid-session.
• Squad tools: // team chat, the Warden aura (allied ships near a Warden recharge 35% faster), and the Comet warp beacon — press T to jump to your team's Comet across the map. Allies can see stealthed Daggers; enemies can't.

Netcode

Built for PvP: 30 Hz binary snapshots both directions (a 24-byte ship state instead of JSON), a jitter buffer that renders remote ships ~100 ms in the past and interpolates between timestamped snapshots — with capped extrapolation on packet loss, so ships glide instead of teleporting — plus server-side sanity validation (position/speed clamps, per-weapon fire-rate caps, damage caps, death-spam guards). Bots back-fill: they stand down as humans join and rejoin as the zone empties.

Play solo (no install)

Open index.html in any modern browser, pick a mode and a ship, and fly.

Works on phones and tablets too: a virtual stick appears under your left thumb (point it where you want to fly), weapon buttons sit under your right, and every menu is tappable — the hosted zone is fully playable from mobile.

Fullscreen on mobile: tap the ⛶ button (top right, next to pause) on Android and desktop browsers. iPhone Safari has no fullscreen API — instead use Share → Add to Home Screen: the game ships installable-app metadata, so the home-screen icon launches it chrome-less and fullscreen on both platforms. Adaptive quality: if a device can't hold the frame rate, the game automatically steps its render budget down (native-resolution rendering first, then a lean mode without bloom) until the fight is smooth — map size never affects frame rate, since only the visible chunks are ever drawn.

Play online (multiplayer)

node server.js            # one command, zero npm dependencies

Everyone opens http://<host>:8666 and presses O — Online multiplayer (the connect screen shows live zone status first). Pick a callsign — it's your persistent identity — and a ship, and you're in, auto-balanced onto blue or red. Configuration is all environment variables:

PORT=9000 BOTS=6 GOAL=50 MODE=teams|core|ffa MAP=nexus|gauntlet|rings \
DISCORD_WEBHOOK=https://discord.com/api/webhooks/... node server.js

A different server can be targeted with ?server=host:port in the URL. The architecture is an owner-trusting relay: each client owns its ship, the server authoritatively runs bots, prizes, rounds, duels, and the ladder, and both sides run the same simulation code (sim.js) on the same map seed.

The hangar — 8 fleet hulls + the NOVA class

Ship	Character
Corsair	The duelist — heavy single shots
Meteor	Bomber with factory proximity-fused splash artillery
Hornet	Rapid-fire bullet hose — a sensor ghost that never paints on radar
Titan	Slow dreadnought, colossal energy, L3 bombs
Comet	Fastest interceptor in the zone, twin linked cannons
Dagger	Tiny assassin — off enemy radar, dim to the eye
Paladin	Broad-winged all-rounder — the only hull whose bombs ricochet, three times, down corridors
Warden	Support hunter with a self-restocking repel rack

A new generation of hulls joins the fleet — each with a mechanic all its own:

NOVA ship	New mechanic
Vanguard	Ships factory MultiFire from spawn — a wall of lead
Aegis	Composite plating absorbs 28% of all incoming damage
Reaper	Leeches 30% of the damage it deals back as energy
Phantom	Blink drive: R teleports 240m forward — straight through walls

The combat system

• Inertial flight with authority — momentum rules mid-fight, but each hull has coast damping: hands off the keys and a Dagger settles crisply while a Titan drifts on. Precision when you want it, physics when you don't.
• Precision controls — keys don't slam straight to full authority: a tap nudges your nose a degree or two or eases you forward for fine aiming, while a hold ramps to the hull's full turn rate and thrust in a fraction of a second. Agile hulls respond near-instantly; heavies ramp slower, so the Titan feels massive and the Dagger feels telepathic. Input is sampled at the fixed simulation rate, so handling is identical at any frame rate.
• Energy warfare — one bar is shields and ammo; a hit that lands with nothing left kills you.
• Leveled weapons — L1–L3 color-coded bullets and bombs with splash and knockback; every bullet ricochets off walls, while bouncing bombs are a hull specialty (the Paladin's, and only the Paladin's) — everyone else's detonate on the wall they hit. Bomb fuses are forgiving: a near miss still counts, and Proximity Fuse greens widen the ring a lot further. Your own bombs still hurt you.
• Greens — anonymous prize boxes: gun/bomb upgrades, MultiFire, proximity fuses, repels, bursts, rockets, energy/recharge/thrust/speed boosts.
• Repel / Burst / Rocket specials, corner radar, green kill-feed chat, bounty, and full loadout reset on death — dying costs you everything you collected, which is exactly why it matters.

The look

• Ships are solid, metallic, shaded craft rendered through 36-frame rotation sprite atlases with fixed top-left lighting — a crisp pre-rendered-sprite feel with baked lighting and rotation snap, drawn procedurally with hull plates, team-color accents, panel seams, engine nozzles, and cockpit glass with specular glints.
• Maps are solid chunky bevelled tiles with per-tile tonal variation and rock speckle, edged with a faint energized rim — steel and stone, not wireframe. The huge sector bakes lazily in 512px chunks with an LRU cache, so even the 8192px map costs one drawImage per visible chunk.
• Bullets and bombs wear their level colors (L1 red-orange, L2 yellow, L3 blue); space is near-black with a whisper of nebula.
• On top of that, the modern layer: subtle bloom post-processing, engine flames with white-hot cores, motion trails, debris and shockwave explosions, muzzle flashes, hex spawn shields, blink warp effects, and screen shake.
• All audio is synthesized live — zero asset files. Sound effects (guns, bombs, explosions, repels, blinks, bounces, low-energy warnings) are WebAudio-generated with distance attenuation, and the soundtrack is adaptive generative rave electronica with four regional palettes — the score has two axes: WHERE you are picks the palette, the fight picks the intensity. Frontier (deep space): the A-minor home identity at 126 BPM. Home (your squad's own quadrant): relative- major warmth at 112 BPM, bell-heavy, soft kick, no acid — a safe harbor. Core (the contested core, or any enemy squad's space): phrygian ♭II war harmony at 132 BPM. Storm (the Maelstrom): diminished clusters at 138 BPM over a saw drone, dissonant chimes, an acid line that runs diminished and never lets up. The same two-bar theme hook threads through every palette (A minor being C major's relative), and palette changes wait for a musical seam — except the storm, which takes over immediately. Under all of it, a music director reads the fight — enemy proximity, hits, kills — into a live intensity and steers the arrangement bar by bar. Cruise empty space and it stays ambient (detuned pads, glass bells whispering the theme, space echo); contact closes in and an eight-bar build starts climbing — accelerating snare rolls, a four-bar riser, the filter opening; then the drop: punchy four-on-the-floor kick, rolling sub-layered bass with passing tones, shaker groove with swing, claps, ghost snares, tom fills, and eight-bar turns alternating between a resonant acid lead with rave stabs and a supersaw anthem playing the theme over rave piano jabs. While the fight rages the drop keeps extending itself; when it's over, a weightless breakdown. An ambush can cut a quiet passage straight into the build. Chord progressions rotate on every ride up, glued by a bus compressor. Toggle with N (remembered between sessions), mute all with M.
• AI pilots with target leading, wall avoidance, dodging, fleeing, repel/burst usage, and prize hunting — the zone fights on with or without you (watch the attract mode behind the title screen).
• Fixed-timestep simulation decoupled from rendering, HiDPI canvas, live leaderboard, persistent best score and callsign.

Controls

Key	Action
W / ↑	Thrust
S / ↓	Reverse thrust (near-full power)
← →	Rotate
A / D	Strafe left / right
Space / Ctrl	Guns — all bullets ricochet off walls
Shift / B	Bomb
E	Repel
Q	Burst
R	Rocket (Blink on the Phantom)
T	Warp home — your mothership (freelance: the core). In matches: warp to your team's Comet
Y	Drop a waypoint beacon / warp back to it · Shift+Y moves it
V	Cycle which contract the course pointer tracks
Tab (hold)	Standings — live top 14 with kills and deaths
Enter	Chat (online) — /duel /accept /stats /votemap /help, // for team
P / Esc	Pause / menu
K	Rebind controls — every key above is remappable
U / J / I	Upgrade bay / contract board / module hold (The Zone)
G	Dock with / launch from your squad's carrier
M	Mute all · N Music on/off · F Fullscreen

Every flight and weapon key is remappable from the controls screen (K, or from the pause menu): ↑ ↓ to pick an action, Enter to capture the next key you press, Shift+R to restore defaults. A key only ever serves one action — binding it somewhere new takes it away from wherever it was. Your layout is saved in the browser.

Architecture

File	Role
sim.js	Shared simulation core (UMD): map gen, ships, weapons, AI, damage. No DOM. Runs in browser and Node.
client.js	Renderer, input, menus, audio, netcode client.
server.js	Zero-dependency zone server: static hosting + hand-rolled RFC 6455 WebSocket endpoint + authoritative bots/prizes + relay.
dev/smoke.js	Headless test: 90 s sim combat, stub-DOM client run, and a real server with two WebSocket clients exercising the whole protocol.
dev/visual.js	Pixel assertions the sim suite structurally cannot make — bakes the real sprites in Chromium and checks hull silhouettes, the contract board, and that a frame actually paints.
dev/perf.js	Frame-rate harness. Drives real scenes on a pinned world seed and measures presented frames, so an A/B compares the same terrain rather than two dice rolls.
dev/shots.js	Screenshot capture. Every image in this README is a real frame of the real client — no mockups, no compositing.

node dev/smoke.js         # sim, client and server layers
node dev/visual.js        # pixel-level art regressions
node dev/perf.js          # fps per scene, desktop and phone viewports
node dev/shots.js         # regenerate assets/*.png
node dev/build.js         # bundle everything into interstellar.html

Note that Canvas2D defers rasterization, so timing drawImage calls in a loop measures command recording, not pixels — the numbers look great and mean nothing. dev/perf.js unthrottles the compositor and counts presented frames instead, which is the one metric that cannot lie.

Performance

The scenery is soft — gradient nebulae, hazed planets, a blurred galaxy — and it was being rendered at full gameplay resolution, costing more per frame than the entire game did (9.3 ms against 1.2 ms for everything that moves). It now composites into a half-resolution buffer that upscales in one blit, with the static sky gradient baked once at resize and off-screen set pieces culled; stars and ships stay pin-sharp on top, where sharpness is actually visible. Sprite atlases quantize their hue and evict LRU, terrain chunks bake on a per-frame budget with a prefetch ring, and bloom — the single most expensive pass, ~45% of the frame — is shed by the first quality step-down rather than the second.

Measured on one pinned world, presented frames, before → after:

Scene	1600×900	390×844
Open frontier	45.9 → 50.8 fps	95.3 → 141.9 fps
14-ship brawl	38.3 → 56.4 fps	88.6 → 128.9 fps
Under a carrier	34.8 → 46.5 fps	107.4 → 146.2 fps

Roadmap

Ordered by what actually blocks what, from a full review of the codebase.

Near term — correctness and trust

• Online module drops. Loot currently drops in Zone worlds (the solo MMO); the online zone needs a drop+/loot relay with the same proximity validation the relic path already uses.
• Live boss hull sync. Online, capital hull points ride a 5-second caps broadcast, so a squad boss fight watches the bar snap rather than drain. Piggyback hp deltas on the existing caphit relay (or tighten the sync to 1 s) and the fight reads live.
• Dreadnought loot scaling. Solo kill times measured 5 s / 21 s / 54 s across the boss tiers — a sound ladder — but payout should probably scale with participants so a six-pilot kill doesn't split ¢7,200 into pocket change. Needs online playtesting first.

Mid term — renderer and scale ceilings

• Emissive bloom buffer. Bloom is the largest remaining render cost (~45% of a desktop frame) and it re-samples the whole canvas, scenery included. Drawing glows, engine wash, and projectiles into a dedicated additive buffer and blooming only that would roughly halve desktop frame time — and stop the backdrop from glowing.
• Interest management. Snapshots are O(clients × ships) at 30 Hz; every client hears about every ship in a 115 km world. Beyond ~30 players the relay should send only ships within scanner range — the quadrant lattice is already the natural bucket structure.
• Spatial hash for projectiles. Bullet–ship collision is a full cross product. Fine at 40 ships; an actual MMO population wants a coarse grid.
• Durable zone state. The server persists pilots to a JSON file with debounced writes; territory and round state die with the process. An append-only log (still zero-dependency) would let a zone restart without amnesia.
• Gamepad support (touch controls shipped: virtual stick + weapon buttons, tappable menus, phone-compact HUD).

Long term — the big swings

• WebGL2 renderer. Canvas2D is the hard ceiling — every sprite is a CPU-side composite. Batching the existing atlases through WebGL2 lifts desktop several-fold and makes phone bloom free; the sprite pipeline already renders into atlases, so the art survives unchanged.
• Sharded zones. One process is one zone. A gateway handing pilots between zone processes (per-galaxy-quadrant) with cross-zone chat is the real MMO shape, and the owner-trusting relay design was chosen so this splits cleanly.
• Mines, decoys, portals; flag capture and ball modes; squad-vs-squad ladders — the classic-zone toolbox, in roughly that order.
• Replay capture. The binary snapshot stream already contains a match; writing it to disk and replaying it through the existing jitter buffer is most of a killcam/replay system.

Known limits, accepted deliberately

• The netcode trusts each client about its own ship (SubSpace's own model). Server-side sanity caps bound speed, fire rate, damage, and kill claims, but a modified client can still fly dishonestly. Full server authority is a different game architecture, not a patch.
• interstellar.html is a build artifact committed for zero-setup play; it regenerates via node dev/build.js.
• Perf numbers in this README come from software rasterization in CI-class containers (and shared-host CPU varies run to run — the A/B pairs above were measured back-to-back in the same window); real hardware runs far faster, and relative wins are what transfer.