Dots On A Map #3: circle selector component

This is a simple setup of Leaflet (via Mapbox) with d3 to show dots on a map. This can serve as a base for many interesting geographically based visualizations

Nice overview of using d3 + Leaflet. I found this slightly simpler to use than Mike's classic post.

Built with blockbuilder.org

forked from enjalot's block: dots on a map: setup-gl

forked from enjalot's block: dots on a map-gl: circle

forked from enjalot's block: Dots On A Map #3: circle selector component

<!DOCTYPE html>
<head>
  <meta charset="utf-8">
  
  <meta name='viewport' content='initial-scale=1,maximum-scale=1,user-scalable=no' />
  <script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.5.5/d3.min.js"></script>
  <script src='https://api.tiles.mapbox.com/mapbox-gl-js/v0.12.0/mapbox-gl.js'></script>
  <link href='https://api.tiles.mapbox.com/mapbox-gl-js/v0.12.0/mapbox-gl.css' rel='stylesheet' />
  
  <script src="selector.js"></script>

<body>
  <nav>
    <a id="circle" class="active">draw circle</a>
  </nav>
  <div id="map"></div>
  <script>
  
    mapboxgl.accessToken = 'pk.eyJ1IjoiZW5qYWxvdCIsImEiOiJjaWhtdmxhNTIwb25zdHBsejk0NGdhODJhIn0.2-F2hS_oTZenAWc0BMf_uw'
    
    //Setup mapbox-gl map
    var map = new mapboxgl.Map({
      container: 'map', // container id
      style: 'mapbox://styles/enjalot/cihmvv7kg004v91kn22zjptsc',
      center: [-0.1,51.5119112],
      zoom: 13.5,
    })
    map.dragPan.disable();
    map.scrollZoom.disable();
    
    // Setup our svg layer that we can manipulate with d3
    var container = map.getCanvasContainer()
    var svg = d3.select(container).append("svg")

circleControl.on("update", function() {
        svg.selectAll("circle.dot").style({
          fill: function(d) {
            var thisDist = circleControl.distance(d);
            var circleDist = circleControl.distance()
            if(thisDist < circleDist) {
              return "#ff8eec";
            } else {
              return "#0082a3"
            }
          }
        })
      })
      circleControl.on("clear", function() {
        svg.selectAll("circle.dot").style("fill", "#0082a3")
      })
      
      function render() {
        dots.attr({
          cx: function(d) { 
            var x = project(d).x;
            return x
          },
          cy: function(d) { 
            var y = project(d).y;
            return y
          },
        })
        
        circleControl.update(svg)
      }

// re-render our visualization whenever the view changes
      map.on("viewreset", function() {
        render()
      })
      map.on("move", function() {
        render()
      })

// render our initial visualization
      render()
    })
  </script>
</body>

https://cdnjs.cloudflare.com/ajax/libs/d3/3.5.5/d3.min.js

https://api.tiles.mapbox.com/mapbox-gl-js/v0.12.0/mapbox-gl.js