A Julia implementation of the algorithm described in Google's Encoded Polyline Format to encode/decode polylines and plot them using Google Maps.
Parse a GPX file.
using Polyline
# Load gpx file and parse.
gpxFile = readGPX("./examples/route.gpx")
gpxRoute = parseGPX(gpxFile)Encode/decode polyline.
# Encode polyline
polyline = encodePolyline(gpxRoute)
# Decode polyline
route = decodePolyline(polyline)Plot using Google Maps. You need to obtain a token from the static maps API which you can find here: https://developers.google.com/maps/documentation/maps-static/get-api-key
# Then either set the token as the environment variable GOOGLE_MAPS_API
# url = mapsURL(polyline)
# Or pass the API token as an argument.
url = mapsURL(polyline; token="...")
# With the defaults you can plot the route.
getMapImage(url; pathFig="/tmp/fig1.png")
# Full customization.
url = mapsURL(polyline; token="...",
type = "roadmap", # https://developers.google.com/maps/documentation/maps-static/dev-guide#MapTypes
size = 1000,
scale = 2, # https://developers.google.com/maps/documentation/maps-static/dev-guide#scale_values
MarkersStart = (gpxRoute[1, 1], gpxRoute[1, 2]),
MarkersEnd = (gpxRoute[end, 1], gpxRoute[end, 2]))
getMapImage(url; pathFig="/tmp/fig2.png")