Customize the position of the legend for a pie chart?

[wildnz]

How do you customize the position of a legend?  I've got it sitting in the top right corner, when I'd prefer it to be right-middle aligned:

My legends config is simply:

"legends": [
    {
        "title":"Type",
        "stroke":"color",
        "fill":"color",
        "orient": "right"
    }
]

I looked at https://vega.github.io/vega/docs/legends/ but could not figure it out.  
The documentation is very hard to follow if you do not have enough familiarity with vega.

I saw that the documentation says "Allows custom layout by setting the x and y properties within a legend encoding block." 

But I could not work out how or where to add x and y properties and there is no example of this given.

Thanks

[Roy I]

Here is a modified Vega 3.0 "legend" based on this example:

       https://groups.google.com/forum/#!topic/vega-js/bkwVdJyWrDI

The framed legend is custom positioned to the right of the chart.

Vega 3.0.2 spec

-------------------

...

"legends": [

{

 "fill": "scale_color",

 "title": "Web Browser",

 

 "orient": "none",

 

 "padding": {"value": 10},

 

 "encode": {

"symbols": {

 "enter": {

"fillOpacity": {"value": 0.5}

 }

},

"labels": {

 "update": {

"text": {"field": "value"}

 }

},

"legend": {

"update": {

"x": {"signal": "width", "offset": 20}, 

"y": {"signal": "height / 2", "offset": -50},

"stroke": {"value": "lightgrey"}

}

}

 }

}

...