var preloaded = new Array();
function preload_images() {
    for (var i = 0; i < arguments.length; i++){
        preloaded[i] = document.createElement('img');
        preloaded[i].setAttribute('src',arguments[i]);
    };
};
preload_images(
    'images/img_boners_color-trans.png',
    'images/img_boners_greyscale-trans.png',
    'images/img_bubble_right.png',
    'images/img_bubble_left.png',
    'images/img_boner1-bubble-trans.png',
    'images/img_boner2-bubble-trans.png',
    'images/img_boner3-bubble-trans.png',
    'images/img_boner4-bubble-trans.png',
    'images/img_boner5-bubble-trans.png',
    'images/img_boner6-bubble-trans.png',
    'images/img_boner7-bubble-trans.png',
    'images/img_boner8-bubble-trans.png',
    'images/img_boner1-color-trans.png',
    'images/img_boner2-color-trans.png',
    'images/img_boner3-color-trans.png',
    'images/img_boner4-color-trans.png',
    'images/img_boner5-color-trans.png',
    'images/img_boner6-color-trans.png',
    'images/img_boner7-color-trans.png',
    'images/img_boner8-color-trans.png'
    );