if (document.images) {
    designup       = new Image();
    designup.src   = "http://www.vis-fx.com/_Images/design.off.png" ;
    designdown     = new Image() ;
    designdown.src = "http://www.vis-fx.com/_Images/design.on.png" ;

    animup       = new Image();
    animup.src   = "http://www.vis-fx.com/_Images/3d.off.png" ;
    animdown     = new Image() ;
    animdown.src = "http://www.vis-fx.com/_Images/3d.on.png" ;
    
    infoup       = new Image();
    infoup.src   = "http://www.vis-fx.com/_Images/info.off.png" ;
    infodown     = new Image() ;
    infodown.src = "http://www.vis-fx.com/_Images/info.on.png" ;

}
function buttondown( buttonname )
{
    if (document.images) {
      document[ buttonname ].src = eval( buttonname + "down.src" );
    }
}
function buttonup ( buttonname )
{
    if (document.images) {
      document[ buttonname ].src = eval( buttonname + "up.src" );
    }
}
//-->