d3.layout.triangle = function(){

  "use strict";

    var exports = {};
	var d3 = window.d3;

	var pts = [];
	var width = 100,
		height = 100,
		offsetX = 0,
		offsetY = 0;
		
	function triangle(data) {
		return triangle.points(data);
	}

	triangle.points = function(data) {
		if (!arguments.length) return pts;
		var qty = data.length, i = -1;
		var halfW = width / 2;
		var sx = d3.scale.linear().domain([0, qty]).range([0, halfW]);
		var sy = d3.scale.linear().domain([0, qty]).range([0, height]);
		while (++i < qty) {
			var d = data[i]; // if not object, make it so
			var level = [
				[width-sx(i), sy(i)],
				[sx(i), sy(i-1)],
				[(sx(i+1) * 2), 0]
			];
			var pt = level[i % 3];
			d.x = pt[0] + offsetX;
			d.y = pt[1] + offsetY;
			d.transform = "translate(" + d.x + " " + d.y + ")";
			data[i] = d;
		}
		return data;
	};

	triangle.width = function(number) {
		if (!arguments.length) return width;
		width = number;
		return triangle;
	};

	triangle.height = function(number) {
		if (!arguments.length) return height;
		height = number;
		return triangle;
	};

	triangle.offsetX = function(number) {
		if (!arguments.length) return offsetX;
		offsetX = number;
		return triangle;
	};

	triangle.offsetY = function(number) {
		if (!arguments.length) return offsetY;
		offsetY = number;
		return triangle;
	};

	//		transform: function(d) { return "translate(" + d.x + " " + d.y + ") rotate(" + d.r + ")"; }

	// ---------------------
	//  Public Interface
	// ---------------------
	return triangle;

};