fix(foundry): isolate HGeoZone projection faults

2026-07-22 10:04:18 +03:00
parent 309cddef73
commit ca26702047
5 changed files with 189 additions and 27 deletions
@@ -0,0 +1,47 @@
+/**
+ * Canonicalize a provider-neutral GeoJSON linear ring before it reaches a
+ * Cesium geometry worker. GeoJSON closes a ring by repeating its first
+ * coordinate, while GroundPolylineGeometry with `loop: true` expects an open
+ * sequence. Some source snapshots contain both adjacent duplicates and more
+ * than one closing coordinate; forwarding either shape can create a
+ * zero-length segment and stop Cesium's render loop.
+ *
+ * Invalid coordinates invalidate the complete ring. Silently retaining a
+ * partial polygon would display a boundary the provider never published.
+ *
+ * @param {Array<[number, number]>} ring
+ * @returns {Array<[number, number]>}
+ */
+export function normalizeHGeoZoneRing(ring) {
+  if (!Array.isArray(ring)) return [];
+  /** @type {Array<[number, number]>} */
+  const normalized = [];
+  for (const coordinate of ring) {
+    if (
+      !Array.isArray(coordinate)
+      || coordinate.length < 2
+      || !Number.isFinite(coordinate[0])
+      || !Number.isFinite(coordinate[1])
+      || coordinate[0] < -180
+      || coordinate[0] > 180
+      || coordinate[1] < -90
+      || coordinate[1] > 90
+    ) return [];
+    const next = /** @type {[number, number]} */ ([coordinate[0], coordinate[1]]);
+    if (!sameCoordinate(normalized.at(-1), next)) normalized.push(next);
+  }
+
+  while (normalized.length > 1 && sameCoordinate(normalized[0], normalized.at(-1))) {
+    normalized.pop();
+  }
+  const distinct = new Set(normalized.map(([longitude, latitude]) => `${longitude}:${latitude}`));
+  return distinct.size >= 3 ? normalized : [];
+}
+
+/**
+ * @param {[number, number] | undefined} left
+ * @param {[number, number] | undefined} right
+ */
+function sameCoordinate(left, right) {
+  return Boolean(left && right && left[0] === right[0] && left[1] === right[1]);
+}