Merge pull request #1715 from bilawalsidhu/sameh/vessel-typical-length

Draw a vessel of unknown length at its ship type's typical size

changelog.d/1715-vessel-typical-length.md

@@ -0,0 +1,3 @@
+- Draw a vessel whose feed sends no length at its ship type's typical size, so
+  a cruise ship or container ship no longer shows as its type's smallest model
+  (samehkhamis, #1715).

public/models/fleet/types.json

@@ -1149,6 +1149,7 @@
     70,
     79
    ],
+   "typical_len": 300,
    "rules": [
     {
      "min_len": 70,
@@ -1188,6 +1189,7 @@
     80,
     89
    ],
+   "typical_len": 250,
    "rules": [
     {
      "name_re": "\\bLNG\\b|\\bGAS\\b",
@@ -1214,6 +1216,7 @@
     60,
     69
    ],
+   "typical_len": 140,
    "rules": [
     {
      "min_len": 70,
@@ -1243,6 +1246,7 @@
     37,
     37
    ],
+   "typical_len": 19,
    "rules": [
     {
      "min_len": 35,
@@ -1273,6 +1277,7 @@
     30,
     30
    ],
+   "typical_len": 24,
    "rules": [
     {
      "min_len": 15,
@@ -1343,6 +1348,7 @@
     55,
     55
    ],
+   "typical_len": 40,
    "rules": [
     {
      "min_len": 25,
@@ -1358,6 +1364,7 @@
     40,
     49
    ],
+   "typical_len": 40,
    "rules": [
     {
      "min_len": 20,
@@ -1373,6 +1380,7 @@
     33,
     33
    ],
+   "typical_len": 100,
    "rules": [
     {
      "min_len": 50,

src/data/fleetModels.js

@@ -133,8 +133,9 @@ export function hullBeam(beam) {
 /**
  * The model for a vessel of AIS ship type `shipType` and the reported length
  * and beam (metres) and name: the first rule that matches in the first type
- * range that has one, else `default_vessel`. Drawn at the reported length, as
- * built when it is unknown.
+ * range that has one, else `default_vessel`. Drawn at the reported length;
+ * when it is unknown (most live feeds send none), chosen and drawn at the
+ * range's `typical_len`, else as built.
  * @param {object} types Parsed `types.json`.
  * @param {number} [shipType]
  * @param {number} [length]
@@ -145,13 +146,14 @@ export function hullBeam(beam) {
 export function resolveVessel(types, shipType, length, beam, name) {
   const L = hullLength(length) ?? 0;
   const B = hullBeam(beam) ?? 0;
-  const drawn = L > 0 ? L : null;
   if (shipType !== undefined && shipType !== null) {
     for (const group of types.vessels) {
       if (!(shipType >= group.types[0] && shipType <= group.types[1])) continue;
+      const len = L > 0 ? L : (group.typical_len ?? 0);
+      const drawn = len > 0 ? len : null;
       for (const rule of group.rules) {
-        if (rule.min_len && L < rule.min_len) continue;
-        if (rule.max_len && L > rule.max_len) continue;
+        if (rule.min_len && len < rule.min_len) continue;
+        if (rule.max_len && len > rule.max_len) continue;
         if (rule.name_re && !new RegExp(rule.name_re).test(name ?? ''))
           continue;
         if (rule.max_bl && !(B > 0 && L > 0 && B / L <= rule.max_bl)) continue;
@@ -159,7 +161,7 @@ export function resolveVessel(types, shipType, length, beam, name) {
       }
     }
   }
-  return { model: types.default_vessel, length: drawn };
+  return { model: types.default_vessel, length: L > 0 ? L : null };
 }
 
 /**
@@ -341,18 +343,22 @@ export function aircraftModelSpec(set, { typeCode, type, category } = {}) {
  * @returns {object} {@link fleetModelSpec}
  */
 export function vesselModelSpec(set, { type, length, beam, name } = {}) {
+  // A beam counts only beside a reported length: a vessel drawn at its type's
+  // typical length keeps the model's proportions.
+  const reported = hullLength(length ?? undefined);
+  const hullWidth = reported === undefined ? undefined : (beam ?? undefined);
   const resolved = resolveVessel(
     set.types,
     aisShipTypeCode(type),
-    length ?? undefined,
-    beam ?? undefined,
+    reported,
+    hullWidth,
     name ?? undefined,
   );
   return specOf(
     set,
     resolved,
     (r) => ({ model: set.types.default_vessel, length: r.length }),
-    { beam: beam ?? undefined },
+    { beam: hullWidth },
   );
 }
 

src/data/fleetModels.test.mjs

@@ -57,6 +57,7 @@ const sliceTypes = {
   vessels: [
     {
       types: [70, 79],
+      typical_len: 300,
       rules: [
         { min_len: 70, max_len: 140, max_bl: 0.12, model: 'inland_cargo' },
         {
@@ -133,6 +134,29 @@ test('vessels: the first matching rule of the first type range with one, else th
   });
 });
 
+test("vessels of unknown length are chosen and drawn at their range's typical length", () => {
+  assert.deepEqual(resolveVessel(sliceTypes, 70), {
+    model: 'container_ship',
+    length: 300,
+  });
+  assert.deepEqual(resolveVessel(sliceTypes, 70, 511, 126), {
+    model: 'container_ship',
+    length: 300,
+  });
+  assert.deepEqual(resolveVessel(sliceTypes, 70, 90, 15), {
+    model: 'general_cargo',
+    length: 90,
+  });
+  assert.deepEqual(resolveVessel(sliceTypes, 31), {
+    model: 'tug',
+    length: null,
+  });
+  // Every passenger, cargo and tanker range of the set has one.
+  for (const code of [60, 70, 80]) {
+    assert.ok(resolveVessel(types, code).length > 100, String(code));
+  }
+});
+
 test("vessels: AIS's out-of-range sizes (511 m long, 126 m abeam) are unknown, drawn as built", () => {
   assert.deepEqual(resolveVessel(sliceTypes, 52, 511), {
     model: 'tug',
@@ -267,6 +291,12 @@ test('vessel specs read AIS codes and text families, stretched to the reported b
   const [sx, sy, sz] = box.scaleXYZ;
   assert.ok(Math.abs(sy - 51 / catalog.container_ship.beam) < 1e-12);
   assert.ok(Math.abs(sz - (sx + sy) / 2) < 1e-12);
+  // A beam with no reported length: the type's typical length, in the model's
+  // own proportions, not a typical-length hull squeezed to that beam.
+  const unsized = vesselModelSpec(set, { type: '70', length: 0, beam: 14 });
+  assert.equal(unsized.model, 'container_ship');
+  const [ux, uy, uz] = unsized.scaleXYZ;
+  assert.ok(Math.abs(uy - ux) < 1e-12 && Math.abs(uz - ux) < 1e-12);
   assert.equal(vesselModelSpec(set, { type: 'Tug', length: 30 }).model, 'tug');
   assert.equal(vesselModelSpec(set, { type: '36' }).model, 'sailboat');
   // No type, no size: the generic vessel as built.