var staySec = 3000; //表示時間ミリ秒
var fadeoutSec = 2000; //フェードアウト時間ミリ秒
var fadeinSec = 2000; //フェードイン時間ミリ秒
var imgno = 1;


jQuery.fn.changeImgAndShow = function(){
  $("h1").fadeIn(fadeinSec,function(){$(this).fadeoutAndChangeCss();});
}

jQuery.fn.fadeoutAndChangeCss = function(){
  if(imgno > 4){
    return;
  }

  setTimeout(function(){
    $("h1").fadeOut(fadeoutSec,function(){
      switch(imgno){
        case 1:
          $("h1").css("background-image","url('../images/topkey02.jpg')");
          break;
        case 2:
          $("h1").css("background-image","url('../images/topkey03.jpg')");
          break;
        case 3:
          $("h1").css("background-image","url('../images/topkey04.jpg')");
          break;
        case 4:
          $("h1").css("background-image","url('../images/topkey05.jpg')");
          break;
      }

      imgno += 1;
      $(this).changeImgAndShow();});
  },staySec);
 
  return;
}; 

//Loda時演出開始
$(window).load(function() {
  $(this).fadeoutAndChangeCss();
});

//画像先読み関数
jQuery.preimg = function(){
  var cache = [];
  for(var i = 0; i<arguments.length; i++){
    //jQuery("<img>").attr("src", arguments[i]);
    var cacheImage = document.createElement('img');
    cacheImage.src = arguments[i];
    cache.push(cacheImage);
 }
};
//先読み画像リスト
jQuery.preimg("./images/topkey02.jpg", "./images/topkey03.jpg","./images/topkey04.jpg","./images/topkey05.jpg");