Class ViscaCamera

tracker/src/camera/visca.ts:157–716

  [...b].map((x) => x.toString(16).padStart(2, "0")).join(" ");

export class ViscaCamera implements CameraDriver {
  readonly kind = "visca" as const;

  private socket: dgram.Socket | null = null;
  private seq = 0;
  private inFlight = 0;
  private diag: CameraDiagnostics = {
    kind: "visca",
    connected: false,
    lastSeq: 0,
    inFlight: 0,
  };

  private pose: CameraPose | null = null;
  private lastInquiryReply = 0;
  /** When the last PAN/TILT position reply landed (zoom replies excluded). */
  private lastPanTiltReplyAt = 0;
  /** Signed commanded rates, deg/s — dead-reckons the pose between replies
   *  (position inquiries stall outright around drives on this firmware). */
  private cmdPanDps = 0;
  private cmdTiltDps = 0;

  private inquiryTimer: ReturnType<typeof setInterval> | null = null;
  private commandTimer: ReturnType<typeof setInterval> | null = null;
  /** Latest requested absolute pose (latest-wins throttle). */
  private wanted: CameraPose | null = null;
  /** Last pan/tilt actually transmitted (zoom tracked separately). */
  private lastSent: { panDeg: number; tiltDeg: number } | null = null;
  /** When that absolute was sent + its expected travel time (gate expiry). */
  private lastSentAt = 0;
  private lastSentDurMs = 0;
  private lastSentZoom: number | null = null;
  /** Last velocity-drive command key (dedupe). */
  private lastDrive: string | null = null;
  /** Speed bytes for the pending absolute move. */
  private wantedPanVV = 0x18;
  private wantedTiltWW = 0x14;
  /** Pending absolute move is speed-matched (carrot) — bypass the gate. */
  private wantedMatched = false;

  constructor(private o: ViscaOptions) {}

  start(): void {
    if (this.socket) return;
    this.openSocket();

    // 10 Hz: closed-loop pursuit corrects on pose error — at 5 Hz the error
    // term was up to 200 ms stale, which reads as hunting.
    const inquiryMs = 1000 / (this.o.inquiryHz ?? 10);
    this.inquiryTimer = setInterval(() => {
      // Reply-stall recovery: the firmware addresses replies to the most
      // recent CLIENT and that state machine occasionally wedges (observed
      // during calibration sweeps). A brand-new source port forces it to
      // re-register us; sequence resets alone do not.
      if (this.lastInquiryReply && Date.now() - this.lastInquiryReply > 4000) {
        this.diag.lastError = "inquiry stall — rebinding socket";
        this.openSocket();
        this.lastInquiryReply = Date.now(); // back off one stall window