A Lonely Brush

I put together a stripped-down version of a D3 brush selector to serve as a pallette for chart interactivity. I'll use it as a controller for other visualization interactions, like sliding extent on a pie chart or time range on a map.

<!DOCTYPE html>
<meta charset="utf-8">
<style>

.axis path {
  display: none;
}

.axis line {
  display: none;
}

.grid-background {
  fill: #e2e3e3;
}

.grid line,
.grid path {
  display: none;
}

.brush .extent {
  fill:#3300ff;
  fill-opacity: .125;
  shape-rendering: crispEdges;
}

</style>
<body>
<script src="https://d3js.org/d3.v3.min.js"></script>
<script>

var margin = {top: 20, right: 40, bottom: 20, left: 40},
    width = 500 - margin.left - margin.right,
    height = 400 - margin.top - margin.bottom;

var x = d3.scale.linear()
    .domain([0,100])
    .range([0, width]);

var brush = d3.svg.brush()
    .x(x)
    .extent([30,70])
    .on("brushend", brushended);

var svg = d3.select("body").append("svg")
    .attr("width", width + margin.left + margin.right)
    .attr("height", height + margin.top + margin.bottom)
  .append("g")
    .attr("transform", "translate(" + margin.left + "," + margin.top + ")");

svg.append("rect")
    .attr("class", "grid-background")
    .attr("width", width)
    .attr("height", height);

svg.append("g")
    .attr("class", "x grid")
    .attr("transform", "translate(0," + height + ")");

svg.append("g")
    .attr("class", "x axis")
    .attr("transform", "translate(0," + height + ")");

var gBrush = svg.append("g")
    .attr("class", "brush")
    .call(brush);

gBrush.selectAll("rect")
    .attr("height", height);

function brushended() {
  //Returns the brush extent at the JS console:
  console.log(Math.round(brush.extent()[0]) + "," + Math.round(brush.extent()[1]))
  }

</script>

Modified http://d3js.org/d3.v3.min.js to a secure url

https://d3js.org/d3.v3.min.js