Function encodeRing

test/data/map/encode.js:60–80

(coordinates, encodeOffsets)

}

function encodeRing(coordinates, encodeOffsets) {

    var result = '';

    var prevX = quantize(coordinates[0][0]);
    var prevY = quantize(coordinates[0][1]);
    // Store the origin offset
    encodeOffsets[0] = prevX;
    encodeOffsets[1] = prevY;

    for (var i = 0; i < coordinates.length; i++) {
        var point = coordinates[i];
        result += encodePoint(point[0], prevX);
        result += encodePoint(point[1], prevY);

        prevX = quantize(point[0]);
        prevY = quantize(point[1]);
    }

    return result;
}

function quantize(val) {
    return Math.ceil(val * 1024);