progress

website/src/lib/trackpoint-categories.ts

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+/**
+ * The value of a trackpoint for a category of the engine (surface, highway): `codes` has one entry
+ * per trackpoint, 0 when the value is unknown, else 1 + the index of the value in `names`.
+ */
+export function categoryAt(
+    codes: ArrayLike<number>,
+    names: readonly string[],
+    index: number
+): string | undefined {
+    const code = codes[index];
+    return code ? names[code - 1] : undefined;
+}