extends Node
## Sim tick loop owner. Sim runs at 20 Hz, render at 60 Hz, decoupled.
##
## Speed factor controls how many sim ticks queue per render frame:
##   1×     — 1 tick per 3 render frames  (20 ticks/s)
##   Fast   — 5 ticks per 3 render frames (~100 ticks/s)
##   Ultra  — 12 ticks per 3 render frames (~240 ticks/s)
##   Pause  — 0
##
## Saves are taken between ticks only — never mid-tick — so JobRunner mid-toil
## state round-trips cleanly. See docs/architecture.md "Time / tick model".

const SIM_HZ: int = 20
const TICK_INTERVAL_S: float = 1.0 / float(SIM_HZ)

enum Speed { PAUSE, NORMAL, FAST, ULTRA }

const SPEED_FACTOR: Dictionary = {
	Speed.PAUSE: 0,
	Speed.NORMAL: 1,
	Speed.FAST: 5,
	Speed.ULTRA: 12,
}

var current_speed: Speed = Speed.PAUSE
var tick: int = 0

# Tick-loop body lands in Phase 1.