function GetZoomFactor() {
            var factor = 1;
            if (document.body.getBoundingClientRect) {
                // rect is only in physical pixel size in IE before version 8 
                var rect = document.body.getBoundingClientRect ();
                var physicalW = rect.right - rect.left;
                var logicalW = document.body.offsetWidth;

                 // the zoom level is always an integer percent value
                factor = Math.round ((physicalW / logicalW) * 100) / 100;
            }
            return factor;
        }

        function GetWindowSize () {
            var zoomFactor = GetZoomFactor();
            var h = Math.round (document.documentElement.clientHeight / zoomFactor) - 25;
            var queAltura = document.getElementById("altura");
			queAltura.style.height = h + "px";
			queAltura.style.overflow = "auto";
			
			
			

        }