Speed

The top travel speed of an object type, the launch speed of a weapon's projectile, or the travel ceiling every jumpjet unit shares.

Object top speed

Specification — Object top speed

Applies to: AircraftTypeBuildingTypeInfantryTypeUnitType
File: rules.ini
Section: [<ObjectType ID>]
Value: integer
When omitted: 0Zero is immobile. Every stock type that moves sets the key.

Speed is a percentage of the engine’s top speed, not a distance. The value is clamped to the range 0 to 100 and stored on a scale of 0 to 255: Speed=50 stores 128, and Speed=100 or anything higher stores 255.

[HARV]
Speed=5 ; stores 12 of 255

The stored value is how many leptons the object covers in one game frame at full throttle, before any modifier. A cell is 256 leptons across.

Infantry and vehicles have that distance scaled by:

their owner’s combined ground speed bias;
the veteran speed ability (VeteranSpeed);
a limpet attached to a vehicle (LimpetFactor);
a speed crate;
the throttle the locomotor currently holds;
one half, for a vehicle carrying the flag in capture the flag.

A prone soldier moves at a speed set by Crawls.

An aircraft on the fly locomotor moves at its type’s speed times its throttle; none of the modifiers above apply. A unit on the jumpjet locomotor ignores this key for travel and uses the jumpjet speed instead.

Projectile launch speed

Specification — Projectile launch speed

Applies to: WeaponType
File: rules.ini
Section: [<ObjectType ID>]
Value: speed
When omitted: 0

The value is the speed of the weapon’s projectile, on the same 0 to 100 scale as an object’s top speed. Values outside that range are clamped, and Speed=-1 counts as leaving the key out. What the speed controls depends on the projectile’s ROT:

A homing projectile, with ROT above 0, is launched at one lepton per frame and accelerates to this speed.
Any other projectile is launched at this speed. The launch speed is capped so that the projectile covers at most half the distance to its target in its first frame.

The firer aims ahead of a moving vehicle target by an amount based on its first weapon’s projectile speed. The slower that projectile, the further ahead it aims.

Jumpjet travel ceiling

Specification — Jumpjet travel ceiling

Applies to: global rules
File: rules.ini
Section: [JumpjetControls]
Value: integer
When omitted: 30

Every jumpjet unit travels at no more than this many leptons per game frame. There are 256 leptons to a cell and 15 game frames to the second, so the default of 30 is a little under two cells a second. Acceleration sets how quickly a jumpjet reaches this speed.

[JumpjetControls]
Speed=20  ; about 1.2 cells a second

A jumpjet unit’s own Speed= does not set how fast it travels. It still matters when another object aims ahead of a moving jumpjet vehicle. The lead is worked out from Speed= with the same modifiers a ground vehicle’s speed gets, multiplied by the jumpjet’s current speed as a fraction of this ceiling.

A jumpjet slows down as it arrives, to fractions of this value. Within two cells of its destination it flies at half this speed, and within one cell at three tenths. Within 20 leptons it stops.

See also — Accelerates, SpeedType, Acceleration, TurnRate