text: // Copyright (c) 2015 Uber Technologies, Inc.
  
  // Permission is hereby granted, free of charge, to any person obtaining a copy
  // of this software and associated documentation files (the "Software"), to deal
  // in the Software without restriction, including without limitation the rights
  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  // copies of the Software, and to permit persons to whom the Software is
  // furnished to do so, subject to the following conditions:
  
  // The above copyright notice and this permission notice shall be included in
  // all copies or substantial portions of the Software.
  
  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  // THE SOFTWARE.
  
  import Immutable from 'immutable';
  import d3 from 'd3';
  
  import React, {PropTypes, Component} from 'react';
  import autobind from 'autobind-decorator';
  
  import MapGL, {ScatterplotOverlay} from '../../src';
  
  // San Francisco
  import CITIES from './../data/cities.json';
  const location = CITIES[0];
  
  const normal = d3.random.normal();
  function wiggle(scale) {
    return normal() * scale;
  }
  
  // Example data.
  const locations = Immutable.fromJS(d3.range(4000).map(
    () => [location.longitude + wiggle(0.01), location.latitude + wiggle(0.01)]
  ));
  
  const PROP_TYPES = {
    width: PropTypes.number.isRequired,
    height: PropTypes.number.isRequired
  };
  
  export default class ScatterplotOverlayExample extends Component {
  
    constructor(props) {
      super(props);
      this.state = {
        viewport: {
          latitude: location.latitude,
          longitude: location.longitude,
          zoom: 11,
          startDragLngLat: null,
          isDragging: false
        }
      };
    }
  
    @autobind
    _onChangeViewport(opt) {
      if (this.props.onChangeViewport) {
        return this.props.onChangeViewport(opt);
      }
      this.setState({
        viewport: {
          latitude: opt.latitude,
          longitude: opt.longitude,
          zoom: opt.zoom,
          startDragLngLat: opt.startDragLngLat,
          isDragging: opt.isDragging
        }
      });
    }
  
    render() {
      const viewport = {...this.state.viewport, ...this.props};
      return (
        <MapGL
          { ...viewport }
          onChangeViewport={ this._onChangeViewport }>
  
          <ScatterplotOverlay
            { ...viewport }
            locations={ locations }
            dotRadius={ 2 }
            globalOpacity={ 1 }
            compositeOperation="screen"/>
  
        </MapGL>
      );
    }
  }
  
  ScatterplotOverlayExample.propTypes = PROP_TYPES;
  