projectson = new Image();
projectson.src = "images/projects_on.gif";
projectsoff = new Image();
projectsoff.src = "images/projects_off.gif";

studioon = new Image();
studioon.src = "images/studio_on.gif";
studiooff = new Image();
studiooff.src = "images/studio_off.gif";

contacton = new Image();
contacton.src = "images/contact_on.gif";
contactoff = new Image();
contactoff.src = "images/contact_off.gif";

prevon = new Image();
prevon.src = "images/prev_on.gif";
prevoff = new Image();
prevoff.src = "images/prev_off.gif";

nexton = new Image();
nexton.src = "images/next_on.gif";
nextoff = new Image();
nextoff.src = "images/next_off.gif";

// On function
function imgAct(imgName) {
    document[imgName].src = eval(imgName + "on.src");
}

// Off function
function imgInact(imgName) {
    document[imgName].src = eval(imgName + "off.src");
}