kepler.gl/src/components/plot-container.js

kepler.gl is a webgl based application to visualize large scale location data in the browser

// Copyright (c) 2018 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.

// libraries
import React, {Component} from 'react';
import PropTypes from 'prop-types';
import {createSelector} from 'reselect';
import styled from 'styled-components';
import {StaticMap} from 'react-map-gl';
import debounce from 'lodash.debounce';
import window from 'global/window';

import MapContainerFactory from './map-container';
import {calculateExportImageSize, convertToPng} from 'utils/export-image-utils';
import {scaleMapStyleByResolution} from 'utils/map-style-utils/mapbox-gl-style-editor';
const propTypes = {
  width: PropTypes.number.isRequired,
  height: PropTypes.number.isRequired,
  exportImageSetting: PropTypes.object.isRequired,
  mapFields: PropTypes.object.isRequired
};

PlotContainerFactory.deps = [MapContainerFactory];

const StyledPlotContainer = styled.div`
  .mapboxgl-ctrl-bottom-left,
  .mapboxgl-ctrl-bottom-right {
    display: none;
  }
`;

export default function PlotContainerFactory(MapContainer) {
  class PlotContainer extends Component {
    constructor(props) {
      super(props);
      this._onMapRender = debounce(this._onMapRender, 500);
    }

    componentWillMount() {
      this.props.startExportingImage();
    }

    componentWillReceiveProps(newProps) {
      // re-fetch the new screenshot only when ratio legend or resolution changes
      const checks = ['ratio', 'resolution', 'legend'];
      const shouldRetrieveScreenshot = checks.some(
        item =>
          this.props.exportImageSetting[item] !==
          newProps.exportImageSetting[item]
      );
      if (shouldRetrieveScreenshot) {
        this._retrieveNewScreenshot();
      }
    }

    mapStyleSelector = props => props.mapFields.mapStyle;
    resolutionSelector = props => props.exportImageSetting.resolution;
    scaledMapStyleSelector = createSelector(
      this.mapStyleSelector,
      this.resolutionSelector,
      (mapStyle, resolution) => ({
        bottomMapStyle: scaleMapStyleByResolution(
          mapStyle.bottomMapStyle,
          resolution
        ),
        topMapStyle: scaleMapStyleByResolution(mapStyle.topMapStyle, resolution)
      })
    );

    _onMapRender = map => {
      if (map.isStyleLoaded()) {
        this._retrieveNewScreenshot();
      }
    };

    _retrieveNewScreenshot = () => {
      if (this.plottingAreaRef) {
      // setting windowDevicePixelRatio to 1
      // so that large mapbox base map will load in full
        const savedDevicePixelRatio = window.devicePixelRatio;
        window.devicePixelRatio = 1;

        this.props.startExportingImage();
        convertToPng(this.plottingAreaRef).then(dataUri => {
          this.props.setExportImageDataUri({dataUri});
          window.devicePixelRatio = savedDevicePixelRatio;
        });
      }
    };

    render() {
      const {width, height, exportImageSetting, mapFields} = this.props;
      const {ratio, resolution, legend} = exportImageSetting;
      const exportImageSize = calculateExportImageSize({
        width,
        height,
        ratio,
        resolution
      });

      const mapProps = {
        ...mapFields,
        mapStyle: this.scaledMapStyleSelector(this.props),

        // override viewport based on export settings
        mapState: {
          ...mapFields.mapState,
          ...exportImageSize,
          zoom: mapFields.mapState.zoom + exportImageSize.zoomOffset
        },
        mapControls: {
          // override map legend visibility
          mapLegend: {
            show: legend,
            active: true
          }
        },
        MapComponent: StaticMap
      };

      return (
        <StyledPlotContainer
          style={{position: 'absolute', top: -9999, left: -9999}}
        >
          <div
            ref={element => {
              this.plottingAreaRef = element;
            }}
            style={{
              width: exportImageSize.width,
              height: exportImageSize.height
            }}
          >
            <MapContainer
              index={0}
              onMapRender={this._onMapRender}
              isExport
              {...mapProps}
            />
          </div>
        </StyledPlotContainer>
      );
    }
  }

  PlotContainer.propsTypes = propTypes;
  return PlotContainer;
}