ElPoyo
41 lines
1.1 KiB
Dart
41 lines
1.1 KiB
Dart
import 'package:latlong2/latlong.dart';
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List<LatLng> safeDecodePolyline(String encoded) {
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if (encoded.isEmpty) return [];
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try {
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List<LatLng> poly = [];
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int index = 0, len = encoded.length;
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int lat = 0, lng = 0;
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while (index < len) {
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int b, shift = 0, result = 0;
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do {
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if (index >= len) break;
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b = encoded.codeUnitAt(index++) - 63;
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result |= (b & 0x1f) << shift;
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shift += 5;
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} while (b >= 0x20);
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int dlat = ((result & 1) != 0 ? ~(result >> 1) : (result >> 1));
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lat += dlat;
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shift = 0;
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result = 0;
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do {
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if (index >= len) break;
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b = encoded.codeUnitAt(index++) - 63;
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result |= (b & 0x1f) << shift;
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shift += 5;
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} while (b >= 0x20);
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int dlng = ((result & 1) != 0 ? ~(result >> 1) : (result >> 1));
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lng += dlng;
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double finalLat = (lat / 1e5).clamp(-90.0, 90.0);
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double finalLng = (lng / 1e5).clamp(-180.0, 180.0);
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poly.add(LatLng(finalLat, finalLng));
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}
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return poly;
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} catch (e) {
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return [];
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}
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}
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