@ue-too/board / createKmtInputStateMachine

Function: createKmtInputStateMachine()

createKmtInputStateMachine(context): KmtInputStateMachine

Defined in: packages/board/src/input-interpretation/input-state-machine/kmt-input-state-machine.ts:727

Creates a new KMT (Keyboard/Mouse/Trackpad) input state machine.

Parameters

context

KmtInputContext

The context providing state and canvas access for the state machine

Returns

KmtInputStateMachine

A configured state machine ready to process KMT input events

Remarks

This factory function creates a fully configured state machine with all KMT gesture recognition states. The state machine processes raw input events and produces high-level gesture outputs (pan, zoom, rotate).

State Flow:

IDLE → (spacebar) → READY_TO_PAN_VIA_SPACEBAR → (click) → INITIAL_PAN → PAN
IDLE → (middle-click) → READY_TO_PAN_VIA_SCROLL_WHEEL → PAN_VIA_SCROLL_WHEEL
IDLE → (scroll) → [produces pan or zoom output, stays in IDLE]

Gesture Recognition:

• Pan via spacebar: Spacebar + left-click drag
• Pan via middle-click: Middle-click drag
• Zoom: Ctrl + scroll (mouse) or scroll (trackpad, auto-detected)
• Pan via scroll: Scroll (trackpad) or scroll without Ctrl (varies by device)

Example

const canvasProxy = new CanvasProxy(canvasElement);
const context = new ObservableInputTracker(canvasProxy);
const stateMachine = createKmtInputStateMachine(context);

// Process an event
const result = stateMachine.happens("scroll", {
  deltaX: 0,
  deltaY: 10,
  x: 500,
  y: 300
});

// Check for output
if (result.output) {
  console.log("Gesture recognized:", result.output.type);
}