//Gallery swap image code.
var param = location.search;
var equal_sign = param.indexOf("img=")
var tname = parseInt(param.substring(equal_sign+4,param.length));
if(equal_sign==-1){
	tname="";
}
var total_img = alt_array.length;

function load_images(){
	var y=0;
	var holdlast = total_img-1; //10
	var check_prev = false;
	var check_next = false;
	
	if (tname==""){
		y = 0;
	    document.getElementById("prevdiv").style.visibility='hidden'
	}else{
		y = tname;
		if (tname > 0){
			document.getElementById("prevdiv").style.visibility='visible'
		}else{
			document.getElementById("prevdiv").style.visibility='hidden'
		}
		if (tname+4>holdlast){
			document.getElementById("nextdiv").style.visibility='hidden'
		}
	}
	//first image display in main window and in thumbnail
	if (y <= holdlast){
		document.gallery.src = "../../images/gallery/" + img_prefix + (y) + ".jpg";
		document.gallery0.src = "../../images/gallery/" + img_prefix + (y) + "s.jpg";
		document.getElementById("desc").innerHTML = alt_array[y];
	}else{
		document.gallery.src = "../../images/gallery/blank.gif"
		document.gallery0.src = "../../images/gallery/blank.gif";
	}
	// second image display in thumbnail
	if (y + 1 > holdlast){
		document.gallery1.src = "../../images/gallery/blank.gif";
	}else{
		document.gallery1.src = "../../images/gallery/" + img_prefix + (y+1) + "s.jpg";
	}
	// third image display in thumbnail
	if (y + 2 > holdlast){
		document.gallery2.src = "../../images/gallery/blank.gif";
	}else{
		document.gallery2.src = "../../images/gallery/" + img_prefix + (y+2) + "s.jpg";
	}
	//fourth image display in thumbnail
	if (y + 3 > holdlast){
		document.gallery3.src = "../../images/gallery/blank.gif";
	}else{
		document.gallery3.src = "../../images/gallery/" + img_prefix + (y+3) + "s.jpg";
	}
	var s_next = parseInt(y) + 4;
	var s_prev = parseInt(y) - 4;
	for(n=0;n<document.links.length;n++){
		if (document.links[n].name == "next_page"){
			document.links[n].href = html_filename+"?img="+s_next;
		}
		if (document.links[n].name == "prev_page"){
			document.links[n].href = html_filename+"?img="+s_prev;
		}
	}
}

function swap_img(num){
	var str = eval("document.gallery"+num+".src");
	var ind_1 = str.lastIndexOf("/");
	var file_name = str.substring(ind_1+1,str.length);
	if(file_name != "blank.gif"){
		var ind_2 = file_name.lastIndexOf("s")
		var file_num = file_name.substring(0,ind_2);
		document.gallery.src = "../../images/gallery/" + file_num + ".jpg";
		file_num = (file_num.substr(file_num.lastIndexOf("_") +1, file_num.length - file_num.lastIndexOf("_")));
		document.getElementById("desc").innerHTML = alt_array[file_num];
	}
}