101.在 Vue 3 + OpenLayers 使用 declutter 避免文字标签重叠

1. 前言

在使用 OpenLayers 进行地图开发时，我们经常需要在地图上添加点、线、区域等图形，并给它们附加文字标签。但当地图上的标注较多时，文字标签可能会发生重叠，导致用户无法清晰地查看地图信息。

幸运的是，OpenLayers 提供了 declutter 选项，能够有效地避免文字标签的重叠问题。本文将介绍如何在 Vue 3 + OpenLayers 项目中使用 declutter，并通过示例代码展示如何添加带有时间标签的轨迹点。

2. `declutter` 介绍

declutter 是 OpenLayers VectorLayer（矢量图层）的一个属性，专门用于处理标注（文本或图标）的重叠问题。如果 declutter: true，OpenLayers 会自动调整标注的显示方式，避免文本或图标重叠在一起，提高地图的可读性。

3. 项目环境

Vue 3 + Composition API
OpenLayers
Vite

安装 OpenLayers

npm install ol

4. 代码实现

4.1 创建 Vue 组件

我们创建一个 Vue 组件，在其中初始化 OpenLayers 地图，并使用 declutter 避免标注重叠。

完整代码

<!--* @Author: 彭麒* @Date: 2025/3/13* @Email: 1062470959@qq.com* @Description: 此源码版权归吉檀迦俐所有，可供学习和借鉴或商用。-->
<template><div class="container"><div class="w-full flex justify-center flex-wrap"><div class="font-bold text-[24px]">在Vue3中+OpenLayers使用declutter，避免文字标签重叠</div></div><div id="vue-openlayers"></div></div>
</template><script setup>
import "ol/ol.css";
import {onMounted, ref} from "vue";
import {Map, View} from "ol";
import Tile from "ol/layer/Tile";
import OSM from "ol/source/OSM";
import VectorLayer from "ol/layer/Vector";
import VectorSource from "ol/source/Vector";
import Style from "ol/style/Style";
import Icon from "ol/style/Icon";
import Text from "ol/style/Text";
import Fill from "ol/style/Fill";
import Stroke from "ol/style/Stroke";
import Feature from "ol/Feature";
import {Point, LineString} from "ol/geom";
import startPoint from "@/assets/OpenLayers/startPoint.png";
import endPoint from "@/assets/OpenLayers/endPoint.png";
import pointImg from "@/assets/OpenLayers/point.png";
const map = ref(null);
const trackSource = new VectorSource();
const markersData = ref([[111.44, 24.18, 1604627953],[112.26, 24.48, 1604714353],[113.96, 24.65, 1604800753],[113.44, 24.78, 1604887153],[113.44, 24.98, 1605059953],[113.54, 25.68, 1605146353],
]);const setTrackStyle = (text, img) => {return [new Style({image: new Icon({src: img,anchor: [0.5, 0.5],scale: 0.2,}),text: new Text({font: "12px sans-serif",maxAngle: 30,offsetY: 20,text: text,fill: new Fill({color: "#fff"}),backgroundFill: new Fill({color: "rgba(255,0,0,0.6)"}),backgroundStroke: new Stroke({color: "rgba(255,0,0,0.6)", width: 8}),}),}),];
};const showTrace = (data) => {const lineFeature = new Feature(new LineString(data));lineFeature.setStyle(new Style({stroke: new Stroke({color: "#00f", width: 2})}));trackSource.addFeature(lineFeature);const features = [];data.forEach((point, index) => {let img;if (index === 0) img = startPoint;else if (index === data.length - 1) img = endPoint;else img = pointImgconst feature = new Feature({geometry: new Point([point[0], point[1]]),data: point,});const time = new Date(point[2] * 1000).toISOString().split("T")[0];feature.setStyle(setTrackStyle(`时间: ${time}`, img));features.push(feature);});trackSource.addFeatures(features);
};const initMap = () => {const OSMlayer = new Tile({source: new OSM()});const trackLayer = new VectorLayer({source: trackSource,declutter: true, // 避免标签重叠});map.value = new Map({target: "vue-openlayers",layers: [OSMlayer, trackLayer],view: new View({center: [113.448, 23.986],zoom: 7,projection: "EPSG:4326",}),});
};onMounted(() => {initMap();showTrace(markersData.value);
});</script><style scoped>
.container {width: 840px;height: 590px;margin: 50px auto;border: 1px solid #42B983;
}#vue-openlayers {width: 800px;height: 470px;margin: 0 auto;border: 1px solid #42B983;position: relative;
}
</style>