D3 force-directed graph: update node position

I have just started with the d3 library. I've taken a couple of days exploring the api and reviewing the examples and have started a project of my own based on the force-directed graph example.

How can I update the position of node(s) after tick in case when instead of using simple shapes (square, circle ...) you are drawing nodes using paths?

I have provided an example that can be viewed here: jsFiddle

var svg = d3.select('#view').attr({width: 300, height: 300});

var data = {
    "nodes": [
        {
           "id": "node_0",
           "name": "Node 0",
           "color": "blue",
           "h": 10,
           "w": 20,
           "t": "triangle"
        },....

    ],

    "links": [
        {
            "source": 0,
            "target": 1
        },...

    ]
};

var force = d3.layout.force().size([300, 300])
.linkDistance(50)
.nodes(data.nodes)
.links(data.links).start()

var link = svg.selectAll('.link').data(data.links).enter()
.append('line')
.attr('class', 'link')
.attr({"stroke": "#ccc", "stroke-width": 1.5});

var wrapper = svg.selectAll('.node').data(data.nodes).enter()
.append('g')
.attr('class', 'node')
.attr('x', function(d){return d.x})
.attr('y', function(d){return d.y});

var getShape = function(t, x, y, w, h){
    var points = (t == 'triangle') ? 
        [ [x + w/2, y], [x + w/2 , y], [x + w, y + h], [x, y + h]]
        : 
        [ [x, y], [x + w, y], [x + w, y + h], [x, y + h]];

    return d3.svg.line()(points)
}

var node = wrapper.append('path')
.attr('d', function(d){return getShape(d.t, d.x , d.y, d.h, d.w) })
.attr('x', function(d){return d.x})
.attr('y', function(d){return d.y})
.attr('fill', function(d){return d.color})
.call(force.drag);

force.on('tick', function(){
     link
     .attr('x1', function(d){return d.source.x})
     .attr('y1', function(d){return d.source.y})
     .attr('x2', function(d){return d.target.x})
     .attr('y2', function(d){return d.target.y})

     node
     .attr('cx', function(d){return d.x})
     .attr('cy', function(d){return d.y});
});