World Explorer: objects in space

Every kind of thing a world holds, and why it is there. Every object should have a purpose for the player: something to do with it, or something it does to you. The ones the code gives no purpose yet are listed at the end.

"Solid" follows principles.md: a solid thing stops shots and ships. "Modes" is arcade, campaign or both.

The world's frame

Station (the main base)

The central point of the world, one per world: you dock there, repair, buy, sell at the exchange, take and collect contracts. Most movement in a world starts and ends there.
In the campaign the space round it is a shelter (see principles.md); docking repairs and saves. In the arcade it is the depot (R), shielded while raiders are near.
Not solid: ships fly over its drawing. Cannot be damaged.
Both modes, every world. Where: station, station_size, station_shelter in src/js/worlds.js; dock_station in src/js/station.js; src/js/docking.js; src/js/depot_shield.js.

World gates

Gates to another world: R beside one jumps there once your ship meets the destination's needs (weapons, defence, radiation; allowed_world). Each world has two or three (world.links). A gate faces the world it leads to, as the galaxy chart draws it, well away from the station (placement.md).
Not solid, cannot be damaged.
Campaign only: the arcade moves on to the next world from the depot, so it draws no gates.
Where: world_gates in visual_base_generate_map, src/js/campaign.js; interact in src/js/navigation.js; the jump in src/js/teleport.js.

Portals (local gates)

Cross big distances fast: a pair of gates, A1 and A2, in one world; fly into one and you leave the other. Both ends stand far apart, never by the station, and a pair that cannot keep the rules of placement.md is left out; the arcade's small maps keep six portals. The guide's route uses them, and raiders take them too.
Not solid, cannot be damaged.
Both modes. Where: configure_expedition_portals in src/js/expedition.js; update_player_navigation in src/js/map.js; enemy_waypoint.

Beacons

Three per world: the places of scan stages (the survey robot scans beside one), survey contracts, and the defend relay.
Not solid, cannot be damaged.
Campaign only; the arcade draws none.
Where: beacons in src/js/campaign.js; operation_point in src/js/operations.js; src/js/survey.js.

Race rings and the start line

A ring race's course: a start line with a place for each racer and three lights, and numbered gold rings to fly through in order, the next one lit, the passed ones faded, the last chequered (the finish).
Background: ships and shots pass through them. Campaign, while a race contract waits in the world, and the Races mode. Where: src/js/race.js; placement.md.

Combat zone

The point where elite, boss and recover stages happen; the flagship of a boss stage waits there.
Not drawn unless a contract uses it. Campaign.
Where: combat_zone in src/js/campaign.js; src/js/navigation.js.

Rock and debris

Ore rocks (asteroids in mining fields)

What ore is mined from. Twelve fields of nine rocks per world; every third field is rich and holds the world's resource. In the campaign your drones (H) drill them and carry the units to your hold; in the arcade your shots break them for salvage.
Solid. In the arcade your shots damage them; in the campaign your shots stop on them without damage (see the open question in principles.md). A bar shows once a rock is below full hp.
Both modes, every world. Where: base_generate_map in src/js/map.js; src/js/deposits.js (the reserve), src/js/mining.js, src/js/drones.js; resolve_solid_ore in src/js/flight.js.

Cliffs (arcade Dustfall)

Six rock faces round the middle of the arcade's Dustfall, each leaning over a strip of ground it would fall on (its fall zone, drawn faint, warmer with raiders under it). Shoot the crack in its foot: broken, it rumbles and falls, crushing what is in the zone (raiders, and you) and leaving its rubble there as rocks; where it stood is open. Half of Dustfall's squadrons warp in under a cliff, and the guns turn to a crack with raiders under it.
Solid; your shots damage it, a bar once hit; raiders' shots stop on it. Arcade, Dustfall only. Where: src/js/arcade_cliffs.js; numbers in balance.md.

Drifting asteroids and wrecks

Moving obstacles: they raise the difficulty a little and add noise, so flying is more interesting. A hit costs hull; your shots break them, and the turret shoots one drifting at you when no raider is near. A broken one leaves a little salvage (2).
Solid for you, not for raiders or their shots. Damageable, no bar.
Both modes, every world; 64 placed per world round the station, gates, beacons and fields. Where: generate_drifting_debris, drifting_debris_hit in src/js/expedition.js.

Caches

Salvage lying in space: 22 per world, each five artifacts and a repair kit, energy cell or repair. Taken ones stay taken in the campaign (saved per world).
Pickups, not solid. Both modes. Where: base_generate_map in src/js/map.js; store_world in src/js/campaign.js.

Pickups

What raiders and rocks drop: artifacts (salvage), repairs (+18 hull), energy (+25 pulse), supplies (repair kit, EMP, stasis), and in the campaign cargo. The magnet module pulls them in.
Both modes. Where: drop_pickup, collect_pickup in src/js/upgrades.js; cargo_spill in src/js/resources.js.

Forces

Black holes

A danger to steer round, and a tool: they pull ships in, and the core kills a ship at once, shields or not. The lure mission uses one to destroy the Leviathan. Four per world, six from Ion Reach, eight from Nova Forge, but none in Haven: its small map leaves no place clear of the station and the gates (gravity.js drops a hole it cannot place). Eclipse pulls at 210%.
The arcade's Eclipse, its gravity world, has one hole, and there it bends every shot's way, slings a ship that passes close past its cruising speed, and pulls in raiders that close on you past it (the rest steer out of its pull); one its core takes counts as your kill (src/js/arcade_gravity.js).
Not solid; not damageable. Both modes. Where: base_generate_map and fatal_gravity in src/js/map.js; src/js/gravity.js; src/js/lure.js.

Storm and flare zones

Ion Reach storms: inside an active one, pulse charges +14 a second and the shield loses 12 a second. Nova Forge solar flares: heat +15 a second and a hit of 10 every second. Both warn before they turn on; up to four per world.
Not solid. Both modes in those two worlds. Where: generate_environment, zone_state in src/js/environment.js; src/js/flight.js.

Currents and planetary pull

Verdant's currents carry ships, raiders and pickups; Obsidian's planet pulls ships within 2.1 km, less for hulls with more traction.
Where: world_flow in src/js/environment.js; src/js/flight.js.

Radiation

A field over the whole of Ion Reach, Obsidian, Nova Forge and Eclipse that wears down the ship's radiation shield and then the hull, unless the lining is good enough. Arcade radiation is 35% of the campaign's.
Where: expedition.radiation in the world files; src/js/expedition.js.

Ships

Raiders

The world's faction: they attack you, your structures and your freighters. Five types (chaser, tank, shooter, splitter, lancer) plus a splitter's shards; numbers in balance.md.
In the arcade some are marksmen: they aim where you will be, and a dashed red line from them shows that aim for the half second before they fire.
In the arcade five more kinds have a job each (an interceptor bursting faster than you cruise, a bulwark with a front shield, a carrier launching drones, a sniper with a charging red line, a mine-layer sealing a lane), and a squadron hunts as a pack: a cut-off, flanks, the rest from behind, and a ring round a ship that holds still. Where: src/js/arcade_raiders.js, src/js/arcade_pack.js.
Solid, damageable, a bar once hit, a shield ring. Both modes.
Where: src/js/combat.js, spawn_enemy in src/js/campaign.js, src/js/navigation.js, src/js/update.js.

Elites and flagships

Tougher raiders to hunt: elites lead arcade squadrons and are the targets of elite stages; a flagship ends each arcade world and each boss stage.
Solid, damageable; a flagship's bar is at the top of the screen. Both modes.
Where: src/js/arcade.js; spawn_operation_enemy in src/js/operations.js.

The Leviathan

The lure mission's beast: guns cannot hurt it; lead it into a black hole.
Solid, not damageable by shots. Campaign, Verdant (Haven has no black hole). Where: src/js/lure.js.

A ring race's rivals

The ships you race in a ring race: three or four, each a name, a hull and a colour; they fly the course's rings by a ship's rules, bump, and turbo, an engine's flame behind each in its colour, long on its turbo.
Solid; raiders' shots and rams damage them (a bar once hit), your shots pass through, and they never shoot. Campaign and the Races mode. Where: src/js/race.js.

The convoy's freighter

What escort stages protect: it loads at a mining field and unloads at the station; raiders strike at the stops. G flies you in formation behind it.
Solid; raiders damage it (300 hull in Haven at level 1, growing as the raiders' hits do farther out and at higher levels; shown as a label). Campaign.
Where: update_escort in src/js/operations.js; src/js/formation.js.

The transport line's ship

Your own freighter: it collects ore from your outposts and sells it at the station, with two turrets of its own. Raids come for it.
Not solid; raiders damage it (900 hull, a bar). Campaign.
Where: src/js/transports.js.

Drones

Mining drones (H) drill rocks and carry the load home; two in the bay, four on the Mule Prospector. Orbit drones (a module) circle you and shoot. The builder drone builds what you place with K. The survey robot scans at a beacon while you guard it (80 hull in Haven, more where raiders hit harder; a bar).
Mining drones, the builder and the robot: campaign. Orbit drones: both.
Where: src/js/drones.js, src/js/structures.js, src/js/survey.js, src/js/render.js (orbit drones).

What you build (campaign)

Mining outpost

Stands on a mining field; its two drones mine the rocks into a store of 60 that you or a transport line collect.
Solid; raiders damage it (220 hull, a bar). Where: structure_kinds in src/js/structures.js.

Defense platform

A heavy turret that fires at raiders within 480 m.
Solid; raiders damage it (280 hull, a bar). Where: src/js/structures.js.

Background

Planets and moons

Each world has its planet ("PRIME") and an outer moon, drawn in the sky. Obsidian's planet pulls ships (above); elsewhere they are scenery.
Background, not solid. Where: generate_environment in src/js/environment.js; src/js/world_visuals.js.

Scenery rocks and wrecks

260 + 8 × the world's wave dim shapes behind the world; ships and shots pass through.
Where: base_generate_map in src/js/map.js; render_map in src/js/surfaces.js.

Satellites

In Haven only (the one world with satellite drawings), every fourth scenery item is a satellite, faded and turning slowly.
Where: render_map in src/js/surfaces.js; src/sprites/worlds/haven/satellite-*.svg.

No purpose yet

What the code draws or places without giving the player anything to do with it. Each has a suggestion, only a suggestion.

Satellites (Haven): decoration only; nothing touches them and they do nothing. Suggestion: a satellite in range charts the map round it (as the map's fog of war is cleared today), so Haven teaches charting.
Scenery rocks and wrecks: decoration only, kept dim so they never pass for solid things. Suggestion: none needed beyond depth, or let a scenery wreck hold a cache marker so the eye has a reason to look.
Planets and moons outside Obsidian: decoration only. Suggestion: a planet gives a slow gravity assist (a speed boost along its rim), so the sky is a route too.
The station's drawing as a body: it is not solid, so ships fly over a 1 km structure, against the rule that what looks like an object is one. Suggestion: make the hull solid outside the docking lane.