[Mapbox GL]点的动画效果

        更新每帧的GeoJSON资源实现点的动画效果

<!DOCTYPE html>
<html>
<head>
    <meta charset='utf-8' />
    <title></title>
    <meta name='viewport' content='initial-scale=1,maximum-scale=1,user-scalable=no' />
    <script src='https://api.tiles.mapbox.com/mapbox-gl-js/v0.29.0/mapbox-gl.js'></script>
    <link href='https://api.tiles.mapbox.com/mapbox-gl-js/v0.29.0/mapbox-gl.css' rel='stylesheet' />
    <style>
        body { margin:0; padding:0; }
        #map { position:absolute; top:0; bottom:0; width:100%; }
    </style>
</head>
<body>

<div id='map'></div>
<script>
mapboxgl.accessToken = '<your access token here>';
var map = new mapboxgl.Map({
    container: 'map',
    style: 'mapbox://styles/mapbox/streets-v9',
    center: [0, 0],
    zoom: 2
});

var radius = 20;

function pointOnCircle(angle) {
    return {
        "type": "Point",
        "coordinates": [       /* 计算坐标 */
            Math.cos(angle) * radius,
            Math.sin(angle) * radius
        ]
    };
}

map.on('load', function () {   /* 添加load事件监听器 */
    // Add a source and layer displaying a point which will be animated in a circle.
    map.addSource('point', {
        "type": "geojson",     /* geojson类型数据 */
        "data": pointOnCircle(0)
    });

    map.addLayer({
        "id": "point",
        "source": "point",
        "type": "circle",     /* circle类型layer */
        "paint": {
            "circle-radius": 10,      /* circle半径,单位像素 */
            "circle-color": "#007cbf" /* circle颜色 */
        }
    });

    function animateMarker(timestamp) {
        // Update the data to a new position based on the animation timestamp. The
        // divisor in the expression `timestamp / 1000` controls the animation speed.
        map.getSource('point').setData(pointOnCircle(timestamp / 1000));  /* getSource(id)获取id的source,setData()设置source的数据*/

        // Request the next frame of the animation.
        requestAnimationFrame(animateMarker); /* requestAnimationFrame() 可以实现动画效果,本例即使典型用法,当然也可以返回一个句柄,必要时取消动画 */
    }

    // Start the animation,执行函数实现动画
    animateMarker(0);
});
</script>

</body>
</html>

转载自:https://blog.csdn.net/naipeng/article/details/53816169

You may also like...