var rndImgID;
var homeImgs = new Array();
homeImgs[0] = '/media/main_home1.jpg';
homeImgs[1] = '/media/main_home2.jpg';
homeImgs[2] = '/media/main_home3.jpg';
homeImgs[3] = '/media/main_home4.jpg';

var pageImgs = new Array();
pageImgs[0] = '/media/main_content1.jpg';
pageImgs[1] = '/media/main_content2.jpg';
pageImgs[2] = '/media/main_content3.jpg';
pageImgs[3] = '/media/main_content4.jpg';

function PreloadImages() {
    var tmp;
    for (i = 0; i < homeImgs.length; i++) {
        try {
            tmp = new Image();
            tmp.src = homeImgs[i];
        } catch (e) { }
    }

    for (i = 0; i < pageImgs.length; i++) {
        try {
            tmp = new Image();
            tmp.src = pageImgs[i];
        } catch (e) { }
    }
}
PreloadImages();

function RandomizeHomeImage() {
    RandomizeImage(homeImgs, rndImgID);
}

function RandomizePageImage() {
    RandomizeImage(pageImgs, 'imgMainContent');
}

function RandomizeImage(imgArray, targetID) {
    try {
        if (targetID == null || targetID.length == 0)
            return;

        target = $('#' + targetID);
        if (target == null)
            return;

        var index = Math.floor(Math.random() * imgArray.length);
        target.attr('src', imgArray[index]);
    } catch (e) { }
}