off_img = new Array(7);
off_img[0] = new Image(144,137);
off_img[1] = new Image(144,137);
off_img[2] = new Image(144,137);
off_img[3] = new Image(144,137);
off_img[4] = new Image(144,137);
off_img[5] = new Image(144,137);
off_img[6] = new Image(144,137);

off_img[0].src = "images/corian_g.jpg";
off_img[1].src = "images/spekva_g.jpg";
off_img[2].src = "images/schock_g.jpg";
off_img[3].src = "images/studio_g.jpg";
off_img[4].src = "images/projekty_g.jpg";
off_img[5].src = "images/szpitale_g.jpg";
off_img[6].src = "images/montelli_g.jpg";

// Preload alternate images
alt_img = new Array(7);
alt_img[0] = new Image(144,137);
alt_img[1] = new Image(144,137);
alt_img[2] = new Image(144,137);
alt_img[3] = new Image(144,137);
alt_img[4] = new Image(144,137);
alt_img[5] = new Image(144,137);
alt_img[6] = new Image(144,137);

alt_img[0].src = "images/corian.jpg";
alt_img[1].src = "images/spekva.jpg";
alt_img[2].src = "images/schock.jpg";
alt_img[3].src = "images/studio.jpg";
alt_img[4].src = "images/projekty.jpg";
alt_img[5].src = "images/szpitale.jpg";
alt_img[6].src = "images/montelli.jpg";

function light(number,icon) {
document.images[icon].src=alt_img[number].src
}
function turnoff(number,icon) {
document.images[icon].src=off_img[number].src
}