var preloadFlag = false ;

function newImage( arg )
{
	if (document.images)
	{
		var rslt ;

		rslt = new Image( ) ;
		rslt.src = arg ;
	}
}

// 画像の先読み
function preloadImages( )
{
	if ( document.images )
	{
		var images = new Array( ) ;

		var preloadList = new Array(
			'../../../img/button/12.gif',
			'../../../img/button/12_on.gif',
			'../../../img/button/2.gif',
			'../../../img/button/2_on.gif',
			'../../../img/button/20.gif',
			'../../../img/button/20_on.gif',
			'../../../img/button/28.gif',
			'../../../img/button/28_on.gif',
			'../../../img/button/3.gif',
			'../../../img/button/3_on.gif',
			'../../../img/button/4.gif',
			'../../../img/button/4_on.gif',
			'../../../img/button/6.gif',
			'../../../img/button/6_on.gif',
			'../../../img/button/8.gif',
			'../../../img/button/8_on.gif',
			'../../../img/button/ac_on.gif',
			'../../../img/button/adpt.gif',
			'../../../img/button/adpt_on.gif',
			'../../../img/button/att.gif',
			'../../../img/button/att_on.gif',
			'../../../img/button/auto_on.gif',
			'../../../img/button/bit.gif',
			'../../../img/button/bit_on.gif',
			'../../../img/button/bud.gif',
			'../../../img/button/bud_on.gif',
			'../../../img/button/buster.gif',
			'../../../img/button/buster_on.gif',
			'../../../img/button/cnst_on.gif',
			'../../../img/button/drain.gif',
			'../../../img/button/drain_on.gif',
			'../../../img/button/dril.gif',
			'../../../img/button/dril_on.gif',
			'../../../img/button/driver.gif',
			'../../../img/button/driver_on.gif',
			'../../../img/button/hand_on.gif',
			'../../../img/button/impct_on.gif',
			'../../../img/button/indst.gif',
			'../../../img/button/indst_on.gif',
			'../../../img/button/m_bottom.gif',
			'../../../img/button/m_off.gif',
			'../../../img/button/m_on.gif',
			'../../../img/button/nutset.gif',
			'../../../img/button/nutset_on.gif',
			'../../../img/button/nv.gif',
			'../../../img/button/nv_on.gif',
			'../../../img/button/plug.gif',
			'../../../img/button/plug_on.gif',
			'../../../img/button/power.gif',
			'../../../img/button/power_on.gif',
			'../../../img/button/rsp.gif',
			'../../../img/button/rsp_on.gif',
			'../../../img/button/sino.gif',
			'../../../img/button/sino_on.gif',
			'../../../img/button/spacer.gif',
			'../../../img/button/sst.gif',
			'../../../img/button/sst_on.gif',
			'../../../img/button/stud.gif',
			'../../../img/button/stud_on.gif',
			'../../../img/button/stud2.gif',
			'../../../img/button/stud2_on.gif',
			'../../../img/button/t.gif',
			'../../../img/button/t_on.gif',
			'../../../img/button/ti.gif',
			'../../../img/button/ti_on.gif',
			'../../../img/button/torsion.gif',
			'../../../img/button/torsion_on.gif',
			'../../../img/button/udril.gif',
			'../../../img/button/udril_on.gif',
			'../../../img/button/wheel.gif',
			'../../../img/button/wheel_on.gif',
			'../../../img/button/wrnch.gif',
			'../../../img/button/wrnch_on.gif'
		) ;

		for( var i=0; i<preloadList.length; i++ )
		{
			newImage( preloadList[ i ] ) ;
		}

		preloadFlag = true ;
	}
}

// ロールオーバー
function changeImages( )
{
	var ARG = changeImages.arguments ;

	if ( document.images && (preloadFlag == true) )
	{
		for ( var i=0; i<ARG.length; i+=2 )
		{
			if ( NN4 )
				getImageObj( ARG[ i ] ).src = ARG[i+1] ;
			else
				document.images[ ARG[ i ] ].src = ARG[i+1] ;
		}
	}
}

function getImageObj( imgName, d )
{
	var temp = null ;

	if ( d == null )
	{
		d = document ;
	}

	for ( var i=0 ; i<d.images.length ; i++ )
	{
		if ( d.images[ i ].name == imgName )
			return d.images[ i ] ;
	}

	for ( var i=0; i<d.layers.length; i++ )
	{
		temp = getImageObj( imgName, d.layers[ i ].document ) ;

		if ( temp )
		{
			return temp ;
		}
	}
}

preloadImages( ) ;