How to get center point of html5 map area?

Question

How to get center point of HTML 5 map area? On this web page http://webven.ru/portfolio/istra/page.html there are polygons, with many coordinates. How can I get the center point?

I have tried below code:

function calculateCenterPoint(areas) {
var maxX = 0,
    minX = Infinity,
    maxY = 0,
    minY = Infinity;
Array.prototype.forEach.call(areas, function (e) {
    var i = 0,
        coords = e.getAttribute('coords').split(',');
    while (i < coords.length) {
    var x = parseInt(coords[i++],10),
        y = parseInt(coords[i++],10);
    if (x < minX) minX = x;
    else if (x > maxX) maxX = x;

    if (y < minY) minY = y;
    else if (y > maxY) maxY = y;
    }
});
return {
    x: minX + (maxX - minX) / 2,
    y: minY + (maxY - minY) / 2
};}

But it does not work, for all of the area.

Answer 1

Remove the else in else if (x > maxX) and else if (y > maxY) .

The problem is that in the first iteration of the loop, both conditions can (and will) be true.