Differential D83 Diff 287 src/it/reyboz/bustorino/backend/gtfs/PolylineParser.java

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				package it.reyboz.bustorino.backend.gtfs;

				import org.osmdroid.util.GeoPoint;

				import java.util.ArrayList;

				public final class PolylineParser {
				/**
				* Decode a Google polyline
				* Thanks to https://stackoverflow.com/questions/9341020/how-to-decode-googles-polyline-algorithm
				* @param encodedPolyline the encoded polyline in a string
				* @param initial_capacity for the list
				* @return the list of points correspoding to the polyline
				*/
				public static ArrayList<GeoPoint> decodePolyline(String encodedPolyline, int initial_capacity) {
				ArrayList<GeoPoint> points = new ArrayList<>(initial_capacity);
				int truck = 0;
				int carriage_q = 0;
				int longit=0, latit=0;
				boolean is_lat=true;
				for (int x = 0, xx = encodedPolyline.length(); x < xx; ++x) {
				int i = encodedPolyline.charAt(x);
				i -= 63;
				int _5_bits = i << (32 - 5) >>> (32 - 5);
				truck \|= _5_bits << carriage_q;
				carriage_q += 5;
				boolean is_last = (i & (1 << 5)) == 0;
				if (is_last) {
				boolean is_negative = (truck & 1) == 1;
				truck >>>= 1;
				if (is_negative) {
				truck = ~truck;
				}
				if (is_lat){
				latit += truck;
				is_lat = false;
				} else{
				longit += truck;
				points.add(new GeoPoint((double)latit/1e5,(double)longit/1e5));
				is_lat=true;
				}
				carriage_q = 0;
				truck = 0;
				}
				}
				return points;
				}
				}