When the page loads, you will be presented with the shape of a region (nation, state, province). Your objective is to correctly guess the name of the region in as few guesses as possible. Enter your guess as text in the textbox below the map and click 'Submit.' If you don't know how to spell a region, no problem. Type the first few letters of the name and a list of options will appear. You have a maximum of 6 guesses per region. Your score is calculated as the total number of kilometres between all guesses and the correct region location. The region to guess is shown in blue and your incorrect guesses are shown in progressively darker shades of red.
You can interact with the map by panning or zooming. The controls in the upper left allow for zooming in or out. Below the +/- zoom tools is a button that, when clicked, will zoom you to the extent of all nations currently on the map (unknown region and guesses). The tool below that will zoom you back to the unknown region. By clicking the Gear icon, you can change your distance units (kilometers or miles).
I am glad you asked. Unfortunately, many existing approaches for calculating distance between two regions still rely on region centroids. This means that if you ask for the distance between Canada and the United States, for example, you will get some number larger than zero. In fact, Google will tell you that the countries are 2,260 km apart. Seriously. Try it. In reality, we know that Canada and the United States share a land border meaning that they are adjacent and therefore the distance between them is zero. Currently, our distance calculation uses the Great Circle Distance as calculated by PostGIS's ST_DistanceSpheroid function.
Please send us an email if you have any feedback or suggestions. nationguesser@gmail.com