update method

void update({ required CameraRig cameraRig, required Quaternion controllerOrientation, required double dt, required Vector3 out, })

Writes the estimated world-space hand position into out.

Implementation

void update({
  required CameraRig cameraRig,
  required Quaternion controllerOrientation,
  required double dt,
  required Vector3 out,
}) {
  if (!dt.isFinite || dt < 0) {
    throw ArgumentError.value(dt, 'dt', 'Must be finite and non-negative.');
  }

  cameraRig.headTransform.copyForwardTo(_headForward);
  cameraRig.headTransform.copyRightTo(_headRight);
  cameraRig.headTransform.copyUpTo(_headUp);
  _rotateControllerForward(controllerOrientation);

  final horizontal = _controllerForward.dot(_headRight).clamp(-1.0, 1.0);
  final vertical = _controllerForward.dot(_headUp).clamp(-1.0, 1.0);
  final alignment = _controllerForward.dot(_headForward).clamp(-1.0, 1.0);
  final targetX = restOffset.x + horizontal * horizontalReach;
  final targetY = restOffset.y + vertical * verticalReach;
  final targetZ = restOffset.z - (1 - alignment) * 0.5 * depthReach;

  if (!_initialized || dt == 0) {
    _localX = targetX;
    _localY = targetY;
    _localZ = targetZ;
    _initialized = true;
  } else {
    final alpha = 1 - math.exp(-responsiveness * dt);
    _localX += (targetX - _localX) * alpha;
    _localY += (targetY - _localY) * alpha;
    _localZ += (targetZ - _localZ) * alpha;
  }

  final head = cameraRig.position;
  out.setValues(
    head.x +
        _headRight.x * _localX +
        _headUp.x * _localY +
        _headForward.x * _localZ,
    head.y +
        _headRight.y * _localX +
        _headUp.y * _localY +
        _headForward.y * _localZ,
    head.z +
        _headRight.z * _localX +
        _headUp.z * _localY +
        _headForward.z * _localZ,
  );
}