var imgDir = "img/";
var imgExt = ".gif";

function chgButton(imgObj, mode)
{
	if(mode == undefined) mode = "";
	var imgSrc = imgDir + imgObj.name + mode + imgExt;
	imgObj.src = imgSrc;
}

function ppreimg()
{
	var lloadcomp = false;
	var ppreload = new Array();
	for(i = 0 ; i < ppreloadlist.length ; i++)
	{
		ppreload[i] = new Image();
		ppreload[i].src = ppreloadlist[i];
	}
	lloadcomp = true;
}

var ppreloadlist = new Array
	(
		imgDir + 'top_bt01.gif'
	,	imgDir + 'top_bt01on.gif'
	,	imgDir + 'top_bt02.gif'
	,	imgDir + 'top_bt02on.gif'
	,	imgDir + 'top_bt03.gif'
	,	imgDir + 'top_bt03on.gif'
	,	imgDir + 'top_bt04.gif'
	,	imgDir + 'top_bt04on.gif'
	,	imgDir + 'bt_01.gif'
	,	imgDir + 'bt_01on.gif'
	,	imgDir + 'bt_02.gif'
	,	imgDir + 'bt_02on.gif'
	,	imgDir + 'bt_03.gif'
	,	imgDir + 'bt_03on.gif'
	,	imgDir + 'bt_04.gif'
	,	imgDir + 'bt_04on.gif'
	,	imgDir + 'bt_05.gif'
	,	imgDir + 'bt_05on.gif'
	,	imgDir + 'bt_06.gif'
	,	imgDir + 'bt_06on.gif'
	);
ppreimg();