fix(awareness): wrap north-bound bearings

changelog.d/1390-awareness-bearing-north.md

@@ -0,0 +1,2 @@
+- Render awareness-overlay bearings and courses that round through north as
+  `000°`, rather than `360°` (Rudy Celekli, #1390).

src/layers/awareness/presentation.js

@@ -0,0 +1,10 @@
+/**
+ * Format a compass direction for the awareness overlay.
+ * @param {number} degrees
+ * @returns {string}
+ */
+export function formatAwarenessDirection(degrees) {
+  if (!Number.isFinite(degrees)) return '—';
+  const normalized = ((degrees % 360) + 360) % 360;
+  return String(Math.round(normalized) % 360).padStart(3, '0');
+}

src/layers/awareness/presentation.test.mjs

@@ -0,0 +1,11 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { formatAwarenessDirection } from './presentation.js';
+
+test('awareness bearings that round through north read 000, not 360', () => {
+  assert.equal(formatAwarenessDirection(359.4), '359');
+  assert.equal(formatAwarenessDirection(359.6), '000');
+  assert.equal(formatAwarenessDirection(0), '000');
+  assert.equal(formatAwarenessDirection(-0.4), '000');
+  assert.equal(formatAwarenessDirection(Number.NaN), '—');
+});

src/layers/awareness/rendering.js

@@ -11,6 +11,7 @@ import {
 } from '../../data/militaryAwarenessEngine.js';
 import { bearingBetweenCoordinates } from '../../cockpitMath.js';
 import { AWARENESS_PAGE_SIZE, CONTEXT_RIM_HEIGHT_M } from './policy.js';
+import { formatAwarenessDirection } from './presentation.js';
 
 export function createRendering({
   state: layerState,
@@ -225,12 +226,12 @@ export function createRendering({
           : null;
       const bearingText = Number.isFinite(bearing)
         ? t('BRG {value}°', {
-            value: String(Math.round(bearing)).padStart(3, '0'),
+            value: formatAwarenessDirection(bearing),
           })
         : t('BRG —');
       const courseText = Number.isFinite(item.track)
         ? ` · ${t('CRS {value}°', {
-            value: String(Math.round(item.track)).padStart(3, '0'),
+            value: formatAwarenessDirection(item.track),
           })}`
         : '';
       marker._label.textContent = `${label} · ${formatAwarenessDistance(item.distanceM)}\n${bearingText}${courseText}`;