README.md

Brute-force find which ASCII characters are used in polyline encodings, because I was too tired to think harder.

brute.js

var polyline = require('polyline');

var chars = {};

function generate(length) {
    var coords = [];
    var loc = [0, 0];
    for (var i = 0; i < length; i++) {
        coords.push([loc[0], loc[1]]);
        loc[0] += 3 * (Math.random() - 0.5);
        loc[1] += 3 * (Math.random() - 0.5);
    }
    return coords;
}

for (var i = 0; i < 10000; i++) {
    var encoded = polyline.encode(generate(1000));
    for (var j = 0; j < encoded.length; j++) {
        chars[encoded[j]] = true;
    }
}

process.stdout.write(JSON.stringify(Object.keys(chars).sort()));