Waymission Mission Simulator

A deterministic vehicle mission simulator built with React, TanStack Start, Tailwind CSS, and shadcn/ui.

The simulator provides:

• a vehicle moving counterclockwise around a 100-unit circle centered at (0, 0)
• display-refresh-rate vehicle animation and a 60-second lap at 1×
• play, pause, reset, and 0.5× / 1× / 2× / 4× speed controls
• selectable, draggable Activity nodes with detailed name, color, latitude, longitude, radius-slider, and route-lock configuration
• position events with a configurable 50–60000 ms interval, independent of movement and playback speed
• a server-side NATS relay with separate position and geofence subjects
• a searchable, filterable, paginated TanStack Table event stream with a configurable 100000-event default retention limit and NATS connection status

Run locally

Install dependencies and start the TanStack Start development server:

pnpm install
pnpm dev

The app runs on http://localhost:3010. A NATS server must be reachable from the TanStack Start server process; authentication is not supported in this iteration.

NATS defaults

The NATS server URL and subjects can be changed on screen. Their initial values come from server-side environment variables:

Variable	Fallback
NATS_URL	nats://localhost:4222
NATS_POSITION_SUBJECT	mission.position
NATS_GEOFENCE_SUBJECT	mission.geofence

Example:

NATS_URL=nats://jetson.local:4222 \
NATS_POSITION_SUBJECT=mission.position \
NATS_GEOFENCE_SUBJECT=mission.geofence \
pnpm dev

The browser posts validated event batches to /api/nats. The server route owns and reuses the native NATS TCP connection. Publish targets accept nats:// and tls:// URLs without embedded credentials.

Event contracts

Position events use type: "position.updated". Activity node transitions use type: "node.entered" or type: "node.exited". Every event includes:

• a deterministic event ID and monotonically increasing sequence number
• mission elapsed time and wall-clock occurrence time
• exact latitude/longitude coordinates and heading
• playback speed
• an Activity node snapshot for geofence transitions

Vehicle position is rendered continuously with requestAnimationFrame. Position events use a separate wall-clock timer, so changing the interval between updates never changes movement speed or smoothness. Geofence transitions follow vehicle movement rather than waiting for a position event.

State architecture

src/features/simulator/model.ts contains a pure command-driven state transition model. Runtime state is separate from the versioned, JSON-serializable SimulatorConfiguration, which contains route geometry, telemetry intervals and retention limits, typed nodes, mission identity, and NATS settings.

src/features/simulator/simulator-store.ts owns the per-session TanStack Store and exposes the command controller as its only mutation boundary. React components subscribe with granular useSelector calls, so animation-frame position updates rerender the mission map without rerendering configuration controls.

This boundary is intentional preparation for future configuration persistence and external control clients. Saving configurations and exposing agent control endpoints are not implemented in this iteration.

Commands

pnpm test     # deterministic simulator model contracts
pnpm check    # Biome formatting and lint checks
pnpm build    # production client and server bundles