//===========//
//  Sniffer  //
//===========//
var browser_type = new Object;

browser_type.is_ns4 = (document.layers) ? true:false;
browser_type.is_ie4 = (document.all) ? true:false;
browser_type.is_w3c = (document.getElementById) ? true:false;

//========================================//
//  Initialise cross-browser normalizers  //
//========================================//
norm = new Object;

if (browser_type.is_ie4) {
	norm.start_wrap 	= "document.all.";
	norm.style_object	= ".style";
	norm.end_wrap 		= "";
	norm.show 			= "visible";
	norm.hide 			= "hidden";
	norm.layer_borderx 	= 8;
	norm.layer_bordery 	= 13;
} else if (browser_type.is_w3c) {
	norm.start_wrap		= "document.getElementById('";
	norm.style_object	= ".style";
	norm.end_wrap		= "')";
	norm.show 			= "visible";
	norm.hide 			= "hidden";
	norm.layer_borderx 	= 6;
	norm.layer_bordery 	= 5;
} else if (browser_type.is_ns4) {
	norm.start_wrap 	= "document.layers.";
	norm.style_object	= "";
	norm.end_wrap 		= "";
	norm.show 			= "show";
	norm.hide 			= "hide";
	norm.layer_borderx 	= 10;
	norm.layer_bordery 	= 10;
}

function get_layer( name ) {
	return eval(norm.start_wrap + name + norm.end_wrap);
}

function get_style( object ) {
	return eval('object'+norm.style_object);
}

function get_image( name ) {
	return document.images[name]
}

function get_dims( layer ) {
	dims = new Object;

	if (browser_type.is_ns4) {
		dims.clipw = layer.clip.width;
		dims.cliph = layer.clip.height;
		dims.posx = layer.clip.left;
		dims.posy = layer.clip.top;
		dims.winw  = window.innerWidth + window.pageXOffset;
		dims.winh  = window.innerHeight + window.pageYOffset;
	} else if (browser_type.is_ie4) {
		dims.clipw = layer.offsetWidth;
		dims.cliph = layer.offsetHeight;
		dims.posx = layer.offsetLeft;
		dims.posy = layer.offsetTop;
		dims.winw  = document.body.clientWidth + document.body.scrollLeft;
		dims.winh  = document.body.clientHeight + document.body.scrollTop;
	} else if (browser_type.is_w3c) {
		dims.clipw = layer.offsetWidth;
		dims.cliph = layer.offsetHeight;
		dims.posx = layer.offsetLeft;
		dims.posy = layer.offsetTop;
		dims.winw  = window.innerWidth + window.pageXOffset;
		dims.winh  = window.innerHeight + window.pageYOffset;
	}

	return dims;
}

function clicktoshow( layer ) {
	l = get_layer(layer);
	style = get_style(l);
	style.display = 'block';
}

function clicktohide( layer ) {
	l = get_layer(layer);
	style = get_style(l);
	style.display = 'none';
}