首页 > 技术文章 > deckgl-triplayer流动效果

dxy9527 2021-07-07 14:54 原文

效果:

html:

<html>

<head>
    <script src="https://unpkg.com/deck.gl@^8.4.0/dist.min.js"></script>
    <script src="https://unpkg.com/@deck.gl/carto@^8.4.0/dist.min.js"></script>

    <script src="https://libs.cartocdn.com/mapbox-gl/v1.13.0/mapbox-gl.js"></script>
    <link href="https://libs.cartocdn.com/mapbox-gl/v1.13.0/mapbox-gl.css" rel="stylesheet" />
</head>

<body style="margin: 0; padding: 0;">
    <div id="map" style="width: 100vw; height: 100vh"></div>
</body>

<script type="text/javascript">
    const LOOP_LENGTH = 1800;
    const ANIMATION_SPEED = 0.4;

    async function initialize() {
        deck.carto.setDefaultCredentials({
            username: 'public',
            apiKey: 'default_public',
        });

        // Fetch Data from CARTO
        const query = 'SELECT the_geom, vendor, timestamps FROM new_york_trips';
        const url = `https://public.carto.com/api/v2/sql?q=${query}&format=geojson`;
        const geojsonData = await fetch(url).then(response => response.json());
        // TripsLayer needs data in the following format
        const layerData = geojsonData.features.map(f => ({
            vendor: f.properties.vendor,
            timestamps: f.properties.timestamps,
            path: f.geometry.coordinates[0]
        }));

        const deckgl = new deck.DeckGL({
            container: 'map',
            mapStyle: {
                'version': 8,
                'sources': {
                    'raster-tiles': {
                        'type': 'raster',
                        'tiles': [
                            'https://map.geoq.cn/arcgis/rest/services/ChinaOnlineStreetPurplishBlue/MapServer/tile/{z}/{y}/{x}'
                        ],
                        'tileSize': 256,
                        'attribution':
                            'Map tiles by <a target="_top" rel="noopener" href="http://stamen.com">Stamen Design</a>, under <a target="_top" rel="noopener" href="http://creativecommons.org/licenses/by/3.0">CC BY 3.0</a>. Data by <a target="_top" rel="noopener" href="http://openstreetmap.org">OpenStreetMap</a>, under <a target="_top" rel="noopener" href="http://creativecommons.org/licenses/by-sa/3.0">CC BY SA</a>'
                    }
                },
                'layers': [
                    {
                        'id': 'simple-tiles',
                        'type': 'raster',
                        'source': 'raster-tiles',
                        'minzoom': 0,
                        'maxzoom': 22
                    }
                ]
            },
            initialViewState: {
                longitude: -74,
                latitude: 40.73,
                zoom: 6,
                pitch: 45,
                bearing: 0
            },
            controller: true
        });

        let time = 0;

        function animate() {
            time = (time + ANIMATION_SPEED) % LOOP_LENGTH;
            window.requestAnimationFrame(animate);
        }

        setInterval(() => {
            deckgl.setProps({
                layers: [
                    new deck.TripsLayer({
                        id: 'trips-layer',
                        data: layerData,
                        getPath: d => d.path,
                        getTimestamps: d => d.timestamps,
                        getColor: d => (d.vendor === 0 ? [253, 128, 93] : [23, 184, 190]),
                        opacity: 0.3,
                        widthMinPixels: 2,
                        rounded: true,
                        trailLength: 180,
                        currentTime: time,
                        shadowEnabled: false
                    })
                ]
            });
        }, 50);

        window.requestAnimationFrame(animate);
    }

    initialize();
</script>

</html>

推荐阅读