Input

Systems read actions, not keys. The ActionMap resource maps each action to keys, mouse buttons and gamepad inputs, and the input plugin polls them into the Input resource once per frame.

Reading input

export const PlayerMove = system([Mut(Velocity), IsPlayer], ([v], { res }) => {
  const input = res.get(Input)
  v.x = input.axis.x * 5
  v.z = -input.axis.y * 5
  if (input.pressed('jump')) v.y = 6
})

axis	{ x, y }: right − left and up − down (or the left stick), length at most 1
down(a)	True while the action is held
pressed(a)	True on the step (in Fixed) or frame (elsewhere) it went down
released(a)	True on the step or frame it went up
value(a)	Analog value 0..1 (triggers, stick directions); 0 or 1 for keys
pointer	x, y (canvas pixels), ndcX, ndcY (−1..1, y up), dx, dy, wheel, down

pressed and released are edge-triggered exactly once: once per press in Fixed, however many steps a frame runs, and once per frame elsewhere. A press and release inside one frame still counts.

Actions

Action	Keyboard / mouse	Gamepad
left right up down	WASD, arrow keys	D-pad, left stick
jump	Space	A
fire	Left mouse	RT
alt	Right mouse	LT
interact	E	X
sprint	Left Shift	B
pause	Escape	Start

A binding is a KeyboardEvent.code ('KeyW', 'Space', 'ArrowLeft'), 'Mouse0'..'Mouse2', a gamepad button ('Pad:A', 'Pad:Start', 'Pad:Up', 'Pad:RT', ...) or a stick direction ('Pad:LX+', 'Pad:LY-', 'Pad:RX+', ...). Stick input has a 0.15 deadzone.

Add or change actions with inputPlugin({ actions }) in place of InputPlugin, or at runtime through res.mut(ActionMap) (for a rebinding menu):

inputPlugin({ actions: { ...DEFAULT_ACTIONS, dash: ['KeyQ', 'Pad:RB'] } })

Scripted input

Tests and tools drive input through app.input:

app.input.script([
  { frame: 1, hold: 'right', frames: 30 },   // frames count from the script call; 1 = next frame
  { frame: 10, tap: 'jump' },                // down for one frame
  { frame: 40, press: 'fire' }, { frame: 50, release: 'fire' },
  { frame: 45, press: 'alt', value: 0.5 },   // analog
  { frame: 60, axis: { x: 0, y: 1 } },       // override the move axis; null hands it back
  { frame: 70, key: 'KeyE' },                // a raw key through the action map ({ key, up: true } releases)
  { frame: 80, pointer: { x: 400, y: 300, down: true } },
])

Shortcuts take effect on the next step: app.input.press(a), .release(a), .tap(a), .setAxis(x, y), .clearAxis(), .reset().

kiln run --script input.json plays a script from a JSON file.

app.input.record() records what the game sees as a script (stop() returns it, peek() copies it so far), which script() replays. Session recordings use the same idea for whole play sessions.