 (360 * color[0]) + ', 100%, 50%)';
                    }
                    return 'color:' + color
                })
                .call(force.drag);

        var text = svg.append("g").selectAll("text")
                .data(force.nodes())
                .enter().append("text")
                .attr("x", 8)
                .attr("y", ".31em")
                .text(function(d) { return d.name; });

        // Use elliptical arc path segments to doubly-encode directionality.
        function tick() {
