Paste the following at the end of your initMap function: Since our JavaScript map is already set, we’ll continue by using the Directions Service. You can use the Directions API for server-side requests, or the Directions Service in the Maps JavaScript API for client-side requests on the web. Driving directions are one of the most popular features in Google Maps, so it’s unsurprising that it’s also made available via an API. When the straight line distance is not adequate, you’ll need more than a formula to determine the travel distance. Get Directions with the Maps JavaScript API For a more accurate travel distance, we’ll need to use another feature of the Maps JavaScript API. The Haversine formula is useful for basic proximity, but is insufficient for many use cases, especially within cities. A quick glance at the map shows there is no road or even pathway straight across Central Park. Of course, unless you’re a pigeon, your jaunt between the two locations is likely to be longer. Now we know the straight line distance between The Dakota and The Frick Collection is 0.60 miles (rounded to two decimal places using the JavaScript toFixed function). Load the map and you’ll see the following: Var distance = haversine_distance(mk1, mk2) ĭocument.getElementById('msg').innerHTML = "Distance between markers: " + distance.toFixed(2) + " mi." Calculate and display the distance between markers Add the following lines after the markers in the JavaScript: To visualize the calculation, we can draw a Polyline between the two markers.
Wikipedia has more on the formulation of this popular straight line distance approximation. Known as the Haversine formula, it uses spherical trigonometry to determine the great circle distance between two points.
The simplest method of calculating distance relies on some advanced-looking math. We’ll answer that question with some 200 year-old number crunching.Ĭalculate the straight line distance from latitude and longitude You might be interested to know how far it is from one to the other. Suppose these were both on a New York City tour. And The Frick Collection, an art gallery. The Dakota, perhaps most famous as John Lennon’s home. Here we can see Central Park, as well as two nearby landmarks. * Set the size of the div element that contains the map */Ĭonst center = )
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