Made of little things.

/** World scale and flight tuning. Units are metres/seconds (gamified scale). */

export const WORLD_SEED = 7331;
/** Sea-level radius. At ~40 m altitude, full-throttle cruise circles the planet in about a minute. */
export const PLANET_RADIUS = 560;
export const GRAVITY = 9.8;
/** Fixed simulation step. */
export const SIM_HZ = 120;

export const FLIGHT = {
  /** Lift/drag scale: ½ρS/m. */
  aeroK: 0.01107,
  liftSlope: 9.0,
  /** Critical angle of attack (rad), ~15°. */
  stallAoA: 0.262,
  cd0: 0.06,
  inducedK: 0.045,
  sideForce: 0.6,
  /** Propeller: thrust fades as airspeed approaches propMaxSpeed. */
  staticThrust: 6.37,
  propMaxSpeed: 110,
  boostThrust: 6.5,
  boostDrain: 0.28,
  boostRecharge: 0.07,
  /** Seconds to wait after the meter empties before boost can be used again. */
  boostCooldown: 1.2,
  throttleRate: 0.7,
  /** Max commanded body rates (rad/s). */
  maxPitchRate: 1.7,
  maxRollRate: 2.8,
  maxYawRate: 0.55,
  /** Airspeed at which control surfaces reach full authority. */
  authoritySpeed: 46,
  /** Weathervane stability: nose rotates toward the relative wind. */
  pitchStability: 5,
  /** Hands-off vertical-speed damping (1/s). */
  climbDamping: 0.35,
  yawStability: 4,
  /** Density scale height: air thins with altitude, giving a soft ceiling. */
  densityScale: 220,
  thinAirAltitude: 160,
  cruiseSpeed: 62,
  stallSpeed: 26,
  /** Clearance from ground/water before a crash. */
  crashClearance: 0.9,
  respawnDelay: 5,
  spawnAltitude: 95,
} as const;

/** Fixed forward guns. Unlimited ammunition; tracers are simulated as fast segments. */
export const GUNS = {
  /** Seconds between rounds (the two guns alternate). */
  interval: 0.09,
  /** Maximum shot-time correction: five degrees, shared by every pilot. */
  aimAssistAngle: 5 * Math.PI / 180,
  muzzleSpeed: 300,
  /** Seconds before a round falls away (~420 m range). */
  life: 1.4,
} as const;

/**
 * Battle damage, 0 (intact) to 1 (destroyed) per part. Wing damage rolls the
 * plane toward the damaged side; tail damage trims the nose down. Any part at 1
 * cripples the plane so it falls out of the sky instead of exploding.
 */
export const DAMAGE = {
  perHitWing: 0.07,
  perHitTail: 0.08,
  /** Roll rate (rad/s) toward a fully damaged wing before it breaks. */
  wingRoll: 1.3,
  /** Lift lost per unit of wing damage. */
  wingLift: 0.15,
  /** Nose-down pitch rate (rad/s) at full tail damage before it breaks. */
  tailPitch: 0.12,
  /** Elevator authority lost at full tail damage. */
  tailAuthority: 0.45,
  extraDrag: 0.03,
  /** Crippled: what's left of control and lift. */
  crippledAuthority: 0.12,
  crippledLift: 0.35,
  crippledRoll: 2.4,
  crippledPitch: 0.7,
} as const;

/**
 * Heat-seeking rockets carried under the lower wings. They chase with a limited
 * turn rate, so a hard bank-and-pull can shake one fired from behind; one that
 * loses its target coasts round the planet at its altitude until it finds
 * another, including the pilot who launched it.
 */
export const ROCKETS = {
  capacity: 2,
  /** Seconds to reload one rocket (one at a time). */
  rechargeTime: 8,
  /** Seconds between launches. */
  launchCooldown: 2,
  /** Damage dealt to the part struck: two hits on a part destroy it. */
  damage: 0.5,
  /** Extra speed over the launching plane's. */
  launchKick: 15,
  accel: 60,
  speed: 120,
  /** Maximum turn rate (rad/s). */
  turnRate: 0.9,
  /** Half-angle of the cone a target must be inside to gain a lock. */
  seekerAngle: 25 * Math.PI / 180,
  /** Half-angle of the cone that keeps an existing lock. */
  trackAngle: 40 * Math.PI / 180,
  lockRange: 320,
  /** Seconds before a rocket can lock onto or hit its own launcher. */
  ownerGrace: 4,
  /** Seconds of flight, about one and a half laps of the planet. */
  life: 45,
  /** Added to every hit box (proximity of the rocket's body). */
  radius: 0.5,
  maxInFlight: 16,
} as const;