make packages for dart and npm

2026-04-16 17:48:43 +03:00
parent 9f2a03a979
commit 34dd9ee35a
21 changed files with 1292 additions and 56 deletions
@@ -0,0 +1,34 @@
+import 'package:maplibre_gl/maplibre_gl.dart';
+
+class PolylineUtils {
+  /// Decode a Google-encoded polyline string into a list of LatLng coordinates.
+  static List<LatLng> decode(String encoded) {
+    List<LatLng> points = [];
+    int index = 0, len = encoded.length;
+    int lat = 0, lng = 0;
+
+    while (index < len) {
+      int b, shift = 0, result = 0;
+      do {
+        b = encoded.codeUnitAt(index++) - 63;
+        result |= (b & 0x1f) << shift;
+        shift += 5;
+      } while (b >= 0x20);
+      int dlat = ((result & 1) != 0 ? ~(result >> 1) : (result >> 1));
+      lat += dlat;
+
+      shift = 0;
+      result = 0;
+      do {
+        b = encoded.codeUnitAt(index++) - 63;
+        result |= (b & 0x1f) << shift;
+        shift += 5;
+      } while (b >= 0x20);
+      int dlng = ((result & 1) != 0 ? ~(result >> 1) : (result >> 1));
+      lng += dlng;
+
+      points.add(LatLng(lat / 1E5, lng / 1E5));
+    }
+    return points;
+  }
+}