Draw no buoy for a virtual aid to navigation

A virtual aid (AIS message 21's VirtualAtoN flag) is a mark broadcast
where nothing physical stands, so drawing it as a buoy showed a mark
that is not there. The vessel source record now carries `virtual`
(false unless a source says true; any source may set it), AISStream
sets it from VirtualAtoN, and the vessel layer keeps such an aid's
disc: vesselModelSpec returns null for it and the layer gathers no
model item for it. Its card, selected card and readout add VIRTUAL
after its kind.

src/data/aisLiveVessels.test.mjs

@@ -1916,7 +1916,23 @@ test('the HUD of a selected aid to navigation shows no speed or heading', () =>
     assert.equal(aisLiveVesselsLayer.selectById(harness.record.mmsi), true);
     assert.match(harness.hud.readout.text, /\nPort hand Mark\n/);
     assert.doesNotMatch(harness.hud.readout.text, /SPD|HDG|KT/);
+    harness.record.virtual = true;
+    aisLiveVesselsLayer.selectById(harness.record.mmsi);
+    assert.match(harness.hud.readout.text, /\nPort hand Mark · VIRTUAL\n/);
   } finally {
     harness.cleanup();
   }
 });
+
+test('a virtual aid to navigation card says it is virtual', () => {
+  const aid = makeRecord({
+    mmsi: '993672001',
+    type: 'Isolated danger',
+    virtual: true,
+  });
+  assert.deepEqual(buildVesselCard(aid).details, ['ISOLATED DANGER · VIRTUAL']);
+  assert.equal(
+    buildSelectedVesselCard(aid).details[0],
+    'ISOLATED DANGER · VIRTUAL',
+  );
+});

src/data/aisStreamSentinels.test.mjs

@@ -388,3 +388,25 @@ test('a capped row request keeps every vessel ahead of aids to navigation', () =
     aisStreamRows(vesselCount).every((row) => !row.mmsi.startsWith('99')),
   );
 });
+
+test('a virtual aid to navigation is marked virtual; a real one carries no flag', () => {
+  const aidReport = (mmsi, VirtualAtoN) => ({
+    MessageType: 'AidsToNavigationReport',
+    Message: {
+      AidsToNavigationReport: { UserID: Number(mmsi), Type: 28, VirtualAtoN },
+    },
+    MetaData: {
+      MMSI: mmsi,
+      latitude: 37.79,
+      longitude: -122.52,
+      time_utc: '2026-09-17 20:00:00.000000000 +0000 UTC',
+    },
+  });
+  ingestAisStreamEnvelope(aidReport('993672004', true));
+  ingestAisStreamEnvelope(aidReport('993672005', false));
+  assert.equal(rowFor('993672004').virtual, true);
+  assert.equal('virtual' in rowFor('993672005'), false);
+  // A later real report of the same aid drops the flag.
+  ingestAisStreamEnvelope(aidReport('993672004', false));
+  assert.equal('virtual' in rowFor('993672004'), false);
+});

src/data/fleetModels.js

@@ -443,13 +443,20 @@ export function aircraftModelSpec(
  * ({@link isAidToNavigation}: its type names a buoy, beacon, mark, RACON or
  * light, or its MMSI is an aid's) is the buoy of its mark
  * ({@link aidToNavigationModel}), else {@link DEFAULT_AID_MODEL}, drawn as
- * built and flagged `fixed`: it has no heading to turn to.
+ * built and flagged `fixed`: it has no heading to turn to. A virtual aid
+ * (`virtual`) is broadcast where nothing physical stands, so it has no model.
  * @param {{catalog: object, types: object}} set
  * @param {{type?: string|number|null, mmsi?: string|number|null,
- *   length?: number|null, beam?: number|null, name?: string|null}} vessel
- * @returns {object} {@link fleetModelSpec}, with `fixed` for an aid
+ *   virtual?: boolean, length?: number|null, beam?: number|null,
+ *   name?: string|null}} vessel
+ * @returns {object|null} {@link fleetModelSpec}, with `fixed` for an aid;
+ *   null for a virtual aid
  */
-export function vesselModelSpec(set, { type, mmsi, length, beam, name } = {}) {
+export function vesselModelSpec(
+  set,
+  { type, mmsi, virtual, length, beam, name } = {},
+) {
+  if (virtual === true) return null;
   if (isAidToNavigation({ type, mmsi })) {
     const model = aidToNavigationModel(type);
     const known = model && set.catalog[model] ? model : DEFAULT_AID_MODEL;

src/data/fleetModels.test.mjs

@@ -423,6 +423,15 @@ test('aids to navigation are the buoy of the mark their type names', () => {
   assert.equal(unnamed.model, DEFAULT_AID_MODEL);
   assert.equal(unnamed.fixed, true);
   assert.equal(aidToNavigationModel('Fixed structure off shore'), undefined);
+  // A virtual aid is broadcast where nothing stands: it keeps its disc.
+  assert.equal(
+    vesselModelSpec(set, {
+      type: 'Cardinal Mark N',
+      mmsi: '993672001',
+      virtual: true,
+    }),
+    null,
+  );
   // Vessels, including those that work on buoys, keep their hulls.
   for (const vessel of [
     { type: 'Buoy Tender', mmsi: '366999001', length: 60 },

src/data/vesselTypes.js

@@ -140,11 +140,13 @@ function typeNamesAid(text) {
  * Whether a vessel record is an aid to navigation (a buoy, beacon, mark,
  * RACON or light) rather than a vessel: its type is one of the kinds an aid
  * report names or uses a word for one, or its MMSI is an aid-to-navigation
- * station's. A numeric AIS ship type never names one.
- * @param {{type?: string|number|null, mmsi?: string|number|null}} vessel
+ * station's, or it is a virtual aid. A numeric AIS ship type never names one.
+ * @param {{type?: string|number|null, mmsi?: string|number|null,
+ *   virtual?: boolean}} vessel
  * @returns {boolean}
  */
-export function isAidToNavigation({ type, mmsi } = {}) {
+export function isAidToNavigation({ type, mmsi, virtual } = {}) {
+  if (virtual === true) return true;
   const text = typeof type === 'string' ? type.trim() : String(type ?? '');
   if (text && typeNamesAid(text)) return true;
   if (mmsi === null || mmsi === undefined || mmsi === '') return false;

src/data/vesselTypes.test.mjs

@@ -36,6 +36,11 @@ test('aids to navigation are known by their type, else their MMSI', () => {
     'Emergency wreck marking buoy',
   ])
     assert.equal(isAidToNavigation({ type, mmsi: '' }), true, type);
+  // A virtual aid is an aid whatever its type or MMSI.
+  assert.equal(
+    isAidToNavigation({ type: '', mmsi: '', virtual: true }),
+    true,
+  );
   // AIS aid-to-navigation stations are numbered 99MIDxxxx.
   assert.equal(isAidToNavigation({ type: '', mmsi: '993672001' }), true);
   assert.equal(isAidToNavigation({ type: '0', mmsi: ' 992351234 ' }), true);

src/i18n/locales/ar.json

@@ -777,6 +777,7 @@
   "OTHER": "أخرى",
   "VESSEL": "سفينة",
   "AID TO NAVIGATION": "مساعدة ملاحية",
+  "VIRTUAL": "افتراضي",
   "POS: LIVE": "الموضع: مباشر",
   "POS: {time}Z": "الموضع: {time}Z",
   "AIS: --": "AIS: --",

src/i18n/locales/de.json

@@ -417,6 +417,7 @@
   "{type}  SPD: {speed}  HDG: {heading}": "{type}  SPD: {speed}  HDG: {heading}",
   "VESSEL": "SCHIFF",
   "AID TO NAVIGATION": "SEEZEICHEN",
+  "VIRTUAL": "VIRTUELL",
   "POS: LIVE": "POS: LIVE",
   "POS: {time}Z": "POS: {time}Z",
   "awaiting first AIS position…": "warten auf erste AIS-Position…",

src/i18n/locales/es.json

@@ -651,6 +651,7 @@
   "OTHER": "OTRO",
   "VESSEL": "BUQUE",
   "AID TO NAVIGATION": "AYUDA A LA NAVEGACIÓN",
+  "VIRTUAL": "VIRTUAL",
   "POS: LIVE": "POS: EN VIVO",
   "POS: {time}Z": "POS: {time}Z",
   "AIS: --": "AIS: --",

src/i18n/locales/fr.json

@@ -1292,6 +1292,7 @@
   "{type}  SPD: {speed}  HDG: {heading}": "{type}  SPD : {speed}  HDG : {heading}",
   "VESSEL": "NAVIRE",
   "AID TO NAVIGATION": "AIDE À LA NAVIGATION",
+  "VIRTUAL": "VIRTUEL",
   "{speed}KT": "{speed} ND",
   "{heading}DEG": "{heading}°",
   "POS: LIVE": "POS : DIRECT",

src/i18n/locales/he.json

@@ -1150,6 +1150,7 @@
   "{type}  SPD: {speed}  HDG: {heading}": "{type}  SPD: {speed}  HDG: {heading}",
   "VESSEL": "אונייה",
   "AID TO NAVIGATION": "עזר ניווט",
+  "VIRTUAL": "וירטואלי",
   "{speed}KT": "{speed} קשר",
   "{heading}DEG": "{heading}°",
   "POS: LIVE": "POS: חי",

src/i18n/locales/it.json

@@ -1292,6 +1292,7 @@
   "{type}  SPD: {speed}  HDG: {heading}": "{type}  VEL: {speed}  HDG: {heading}",
   "VESSEL": "NAVE",
   "AID TO NAVIGATION": "AIUTO ALLA NAVIGAZIONE",
+  "VIRTUAL": "VIRTUALE",
   "{speed}KT": "{speed}KT",
   "{heading}DEG": "{heading}°",
   "POS: LIVE": "POS: LIVE",

src/i18n/locales/ja.json

@@ -1254,6 +1254,7 @@
   "{type}  SPD: {speed}  HDG: {heading}": "{type}  SPD: {speed}  HDG: {heading}",
   "VESSEL": "船舶",
   "AID TO NAVIGATION": "航路標識",
+  "VIRTUAL": "仮想",
   "{speed}KT": "{speed} kt",
   "{heading}DEG": "{heading}°",
   "POS: LIVE": "POS: ライブ",

src/i18n/locales/pt.json

@@ -1290,6 +1290,7 @@
   "{type}  SPD: {speed}  HDG: {heading}": "{type}  SPD: {speed}  HDG: {heading}",
   "VESSEL": "EMBARCAÇÃO",
   "AID TO NAVIGATION": "AUXÍLIO À NAVEGAÇÃO",
+  "VIRTUAL": "VIRTUAL",
   "{speed}KT": "{speed} KT",
   "{heading}DEG": "{heading}°",
   "POS: LIVE": "POS: AO VIVO",

src/i18n/locales/ru.json

@@ -395,6 +395,7 @@
   "{type}  SPD: {speed}  HDG: {heading}": "{type}  СКОР: {speed}  КУРС: {heading}",
   "VESSEL": "СУДНО",
   "AID TO NAVIGATION": "СРЕДСТВО НАВИГАЦИИ",
+  "VIRTUAL": "ВИРТУАЛЬНЫЙ",
   "AIS: --": "AIS: --",
   "awaiting first AIS position…": "ожидание первой позиции AIS…",
   "awaiting usable AIS positions…": "ожидание пригодных позиций AIS…",

src/i18n/locales/sv.json

@@ -383,6 +383,7 @@
   "{type}  SPD: {speed}  HDG: {heading}": "{type}  SPD: {speed}  HDG: {heading}",
   "VESSEL": "FARTYG",
   "AID TO NAVIGATION": "SJÖMÄRKE",
+  "VIRTUAL": "VIRTUELL",
   "POS: LIVE": "POS: LIVE",
   "POS: {time}Z": "POS: {time}Z",
   "awaiting first AIS position…": "väntar på första AIS-positionen …",

src/i18n/locales/uk.json

@@ -1310,6 +1310,7 @@
   "{type}  SPD: {speed}  HDG: {heading}": "{type}  ШВИД: {speed}  КУРС: {heading}",
   "VESSEL": "СУДНО",
   "AID TO NAVIGATION": "ЗАСІБ НАВІГАЦІЇ",
+  "VIRTUAL": "ВІРТУАЛЬНИЙ",
   "{speed}KT": "{speed} ВУЗ",
   "{heading}DEG": "{heading}°",
   "POS: LIVE": "ПОЗ.: ОНЛАЙН",

src/i18n/locales/zh-CN.json

@@ -1230,6 +1230,7 @@
   "{type}  SPD: {speed}  HDG: {heading}": "{type}  SPD: {speed}  HDG: {heading}",
   "VESSEL": "船舶",
   "AID TO NAVIGATION": "助航标志",
+  "VIRTUAL": "虚拟",
   "{speed}KT": "{speed} kn",
   "{heading}DEG": "{heading}°",
   "POS: LIVE": "POS：实时",

src/i18n/locales/zh-Hant.json

@@ -1225,6 +1225,7 @@
   "{type}  SPD: {speed}  HDG: {heading}": "{type}  SPD: {speed}  HDG: {heading}",
   "VESSEL": "船舶",
   "AID TO NAVIGATION": "助航標誌",
+  "VIRTUAL": "虛擬",
   "{speed}KT": "{speed} kn",
   "{heading}DEG": "{heading}°",
   "POS: LIVE": "POS：實時",

src/i18n/same-as-english.json

@@ -411,7 +411,8 @@
     "MMSI: {id}",
     "NORAD: {id}",
     "Regional",
-    "{datasets} · {tiles} · {packs}"
+    "{datasets} · {tiles} · {packs}",
+    "VIRTUAL"
   ],
   "fr": [
     "1 min/s",
@@ -1067,7 +1068,8 @@
     "ICAO: {id}",
     "MMSI: {id}",
     "NORAD: {id}",
-    "Regional"
+    "Regional",
+    "VIRTUAL"
   ],
   "ru": [
     "1900–1945",

src/layers/vessels/cards.js

@@ -24,7 +24,10 @@ export function createCards({
       text: [
         t('AIS: {name}', { name: trimHudValue(record.name, 32) }),
         aid
-          ? trimHudValue(record.type || t('AID TO NAVIGATION'), 24)
+          ? aidKind(
+              trimHudValue(record.type || t('AID TO NAVIGATION'), 24),
+              record,
+            )
           : t('{type}  SPD: {speed}  HDG: {heading}', {
               type: trimHudValue(record.type || t('VESSEL'), 24),
               speed: formatSpeed(record.speed),
@@ -60,6 +63,7 @@ export function createCards({
     const aid = isAidToNavigation(record);
     const type = vesselTypeShort(record);
     if (type) parts.push(type);
+    if (record.virtual === true) parts.push(t('VIRTUAL'));
     if (!aid && record.speed !== null && record.speed !== undefined)
       parts.push(formatSpeed(record.speed));
     const direction = record.heading ?? record.course;
@@ -95,7 +99,7 @@ export function createCards({
     const direction = record.heading ?? record.course;
     const details = [
       aid
-        ? vesselTypeShort(record) || t('AID TO NAVIGATION')
+        ? aidKind(vesselTypeShort(record) || t('AID TO NAVIGATION'), record)
         : [
             vesselTypeShort(record) || t('VESSEL'),
             formatSpeed(record.speed),
@@ -125,6 +129,12 @@ export function createCards({
     };
   }
 
+  /** An aid's kind, marked virtual when nothing physical stands there. */
+
+  function aidKind(kind, record) {
+    return record.virtual === true ? `${kind} · ${t('VIRTUAL')}` : kind;
+  }
+
   /** A card's accent: an aid's disc colour, else its ship type's. */
 
   function vesselAccent(record, aid) {

src/layers/vessels/ingestion.js

@@ -218,6 +218,7 @@ export function createIngestion({
       speed: record.speedMps == null ? null : record.speedMps / 0.514444,
       course: record.courseDeg,
       heading: record.headingDeg,
+      virtual: record.virtual === true,
       last_position_epoch:
         record.observedAtMs == null ? null : record.observedAtMs / 1000,
       last_position_UTC:

src/layers/vessels/ownership.test.mjs

@@ -536,6 +536,29 @@ test('an aid to navigation is drawn as a disc, a vessel as its chevron', async (
     return atob(primitive.image.split(',')[1]);
   };
   assert.match(svgOf('993672001'), /<circle/);
+  // The source's virtual flag reaches the layer's record.
+  const recordOf = (id) => [...primitives].find((p) => p.id?.id === id).id;
+  assert.equal(recordOf('993672001').virtual, false);
+  assert.equal(recordOf('366999002').virtual, false);
   assert.doesNotMatch(svgOf('993672001'), /<path/);
   assert.match(svgOf('366999002'), /<path/);
 });
+
+test('a virtual aid to navigation keeps its disc and its virtual flag', async () => {
+  const aid = {
+    ...observation('993672009'),
+    mmsi: '993672009',
+    type: 'Isolated danger',
+    virtual: true,
+  };
+  const { layer, primitives } = setup({
+    async getSnapshot() {
+      return snapshot([aid]);
+    },
+  });
+  await layer.update();
+  const primitive = [...primitives].find((p) => p.id?.id === '993672009');
+  assert.ok(primitive);
+  assert.equal(primitive.id.virtual, true);
+  assert.match(atob(primitive.image.split(',')[1]), /<circle/);
+});

src/layers/vessels/records.js

@@ -31,6 +31,8 @@ export function normalizeVessel(row) {
     speed: finiteNumber(row.speed),
     course: finiteNumber(row.course),
     heading: finiteNumber(row.heading),
+    // A virtual aid to navigation: a mark with nothing physical there.
+    virtual: row.virtual === true,
     lastPositionUtc: String(row.last_position_UTC || ''),
     lastPositionEpoch: finiteNumber(row.last_position_epoch),
     missedRefreshes: 0,
@@ -160,6 +162,7 @@ export class VesselRecords {
         record.speed = next.speed;
         record.course = next.course;
         record.heading = next.heading;
+        record.virtual = next.virtual;
         record.lastPositionUtc = next.lastPositionUtc;
         record.lastPositionEpoch = next.lastPositionEpoch;
         record.missedRefreshes = 0;

src/layers/vessels/rendering.js

@@ -274,8 +274,13 @@ export function createRendering({
     );
   }
 
-  /** The model item for `record`, its spec rebuilt only when its type or size changes. */
+  /**
+   * The model item for `record`, its spec rebuilt only when its type or size
+   * changes; null for a virtual aid to navigation, which keeps its disc: no
+   * buoy stands there (vesselModelSpec).
+   */
   function modelItem(record, set) {
+    if (record.virtual === true) return null;
     let item = modelItems.get(record.id);
     if (!item || item.record !== record)
       item = { record, pickId: record, tint: null, modelOwnsVisual: false };
@@ -309,7 +314,8 @@ export function createRendering({
         limitSq
       )
         continue;
-      into.set(record.id, modelItem(record, set));
+      const item = modelItem(record, set);
+      if (item) into.set(record.id, item);
     }
   }
 
@@ -345,8 +351,10 @@ export function createRendering({
       gatherModelItems(set, next);
     } else {
       for (const [id, item] of modelItems)
-        if (state.records.byId.get(id) === item.record)
-          next.set(id, modelItem(item.record, set));
+        if (state.records.byId.get(id) === item.record) {
+          const kept = modelItem(item.record, set);
+          if (kept) next.set(id, kept);
+        }
     }
     for (const [id, item] of modelItems)
       if (next.get(id) !== item) handBackVisual(item.record, occluder);

src/sources/live/contract.js

@@ -12,7 +12,9 @@
  * snapshots. A vessel record's `id` is whatever its source gives, such as a
  * provider id; its `mmsi` is an optional attribute ('' or absent when
  * unknown), never its key, since vessels can share an MMSI. A source that
- * only has MMSIs uses the MMSI as the id.
+ * only has MMSIs uses the MMSI as the id. A vessel record's `virtual` is true
+ * for a virtual aid to navigation, a mark broadcast where nothing physical
+ * stands (AIS message 21's virtual flag), else false; any source may set it.
  *
  * A source may also declare a timeline (see readSnapshotTimeline): it can
  * answer a snapshot at a given time, so the layer follows the world clock.

src/sources/live/contract.test.mjs

@@ -221,6 +221,18 @@ test('vessel identity, opaque reference and heading/course remain distinct, unkn
   assert.equal(row.altitudeDatum, 'sea-surface');
   assert.equal(row.observedAtMs, now);
   assert.equal('extra' in row, false);
+  // Only a source's own true marks a virtual aid to navigation.
+  assert.equal(row.virtual, false);
+  const base = { mmsi: '993672001', lat: 30, lon: -97 };
+  assert.equal(
+    normalizeVesselObservation({ ...base, virtual: true }).virtual,
+    true,
+  );
+  for (const virtual of ['true', 1, false, null])
+    assert.equal(
+      normalizeVesselObservation({ ...base, virtual }).virtual,
+      false,
+    );
   assert.equal(
     normalizeVesselObservation({ mmsi: 'x', lat: null, lon: null }),
     null,

src/sources/live/vessels.js

@@ -55,6 +55,8 @@ export function normalizeVesselObservation(row, reference = null, id = null) {
       epoch(row.last_position_epoch, 1000) ??
       epoch(Date.parse(row.last_position_UTC)),
     altitudeDatum: 'sea-surface',
+    // A virtual aid to navigation: a mark broadcast with nothing there.
+    virtual: row.virtual === true,
   };
 }