/**
 * jQuery.fullBg
 * Copyright (c) 2010 c.bavota - http://bavotasan.com
 * Dual licensed under MIT and GPL.
 * Date: 02/23/2010
**/
(function($) {
  $.fn.fullBg = function(){
    var bgImg = $(this);		
 

 	function resizeImg() {
 		var imgwidth = bgImg.width();
		var imgheight = bgImg.height();
		
		var winwidth = $(window).width();
		var winheight = $(window).height();
		
		var widthratio = winwidth / imgwidth;
		var heightratio = winheight / imgheight;
		
		var widthdiff = heightratio * imgwidth;
		var heightdiff = widthratio * imgheight;
		
//		var topPos = -(heightdiff-winheight) /2;
		var topPos = 0;//siempre arriba
		var leftPos = -(widthdiff-winwidth) /2;
		
		if(heightdiff>winheight) {
 			bgImg.css({
				width: winwidth+'px',
				//height: heightdiff+'px',
				height: 'auto', //dejamos la proporcion original de la imagen
				left:"0px",
				top:topPos+"px"
			});
		}
		else {
			bgImg.css({
				//width: widthdiff+'px',
				width: 'auto', //dejamos la proporcion original de la imagen
				height: winheight+'px',
				left:leftPos+"px",
				top:"0px"
			});		
		}
	}
/* 
    function resizeImg() {
      var imgwidth = bgImg.width();
      var imgheight = bgImg.height();
 
      var winwidth = $(window).width();
      var winheight = $(window).height();
 
      var widthratio = winwidth / imgwidth;
      var heightratio = winheight / imgheight;
 
      var widthdiff = heightratio * imgwidth;
      var heightdiff = widthratio * imgheight;
 
      if(heightdiff>winheight) {
        bgImg.css({
          width: winwidth+'px',
          height: heightdiff+'px'
        });
      } else {
        bgImg.css({
          width: widthdiff+'px',
          height: winheight+'px'
        });		
      }
    } 
*/
    resizeImg();
    $(window).resize(function() {
      resizeImg();
    }); 
	bgImg.load(function() {
      resizeImg();
    }); 
  };
})(jQuery)