var buttonImages = new Array();
var buttonSwapImages = new Array();
var buttonIDIndexes = new Array();

buttonImages[0] = new Image();
buttonImages[0].src = "./images/home.gif"
buttonImages[1] = new Image();
buttonImages[1].src = "./images/about.gif"
buttonImages[2] = new Image();
buttonImages[2].src = "./images/services.gif"
buttonImages[3] = new Image();
buttonImages[3].src = "./images/contact.gif"

buttonSwapImages[0] = new Image();
buttonSwapImages[0].src = "./images/home_swap.gif"
buttonSwapImages[1] = new Image();
buttonSwapImages[1].src = "./images/about_swap.gif"
buttonSwapImages[2] = new Image();
buttonSwapImages[2].src = "./images/services_swap.gif"
buttonSwapImages[3] = new Image();
buttonSwapImages[3].src = "./images/contact_swap.gif"

buttonIDIndexes['navHome'] = 0;
buttonIDIndexes['navAbout'] = 1;
buttonIDIndexes['navServices'] = 2;
buttonIDIndexes['navContact'] = 3;

function navigationSwap(buttonID) {

	var button = document.all[buttonID];
	button.src = buttonSwapImages[buttonIDIndexes[buttonID]].src;
}

function navigationOff(buttonID) {
	var button = document.all[buttonID];
	button.src = buttonImages[buttonIDIndexes[buttonID]].src;
}