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wzjs 2025/7/21 18:17:30

长春网站seo外包,关键词查找,网站推广的主要途径,兰州网站关键词优化项目演示了如何使用 Turf.js 的 turf.mask() 方法与 OpenLayers 实现地图遮罩布挖洞效果，支持一键生成洞口区域、遮罩布、以及最终合成的遮罩布挖洞图形。📸效果预览（上图为遮罩布在地图上挖出洞后的样式，仅供参考）&am…

项目演示了如何使用 Turf.js 的 turf.mask() 方法与 OpenLayers 实现地图遮罩布挖洞效果，支持一键生成洞口区域、遮罩布、以及最终合成的遮罩布挖洞图形。

📸效果预览

（上图为遮罩布在地图上挖出洞后的样式，仅供参考）

🧩技术栈

Vue3 + Composition API
OpenLayers（地图库）
Turf.js（地理计算库）
Element Plus（UI 控件）
Autonavi 高德地图瓦片源

✨功能介绍

按钮名称	功能描述
绘制小洞	使用 `turf.polygon` 创建一个小洞区域（Polygon）
绘制遮罩布	使用 `turf.polygon` 创建整个大遮罩布区域
合力遮罩打洞	使用 `turf.mask(洞, 遮罩布)` 将遮罩布打上洞
清除图层	清除当前地图上的所有遮罩图形

🧠关键逻辑详解

1️⃣ turf.mask 实现遮罩减洞

const maskResult = () => {turfSource.clear()const hole = turf.polygon(holeData)const mask = turf.polygon(maskData)const masked = turf.mask(hole, JSON.parse(JSON.stringify(mask)))show(masked)
}

turf.polygon()：构建多边形
turf.mask()：将 mask 多边形“剪掉” hole 区域，返回一个挖好洞的多边形

2️⃣ GeoJSON 与 OpenLayers 特征同步

const show = (geojsonData) => {const features = new GeoJSON().readFeatures(geojsonData, {dataProjection: 'EPSG:4326',featureProjection: 'EPSG:3857',})turfSource.addFeatures(features)
}

使用 GeoJSON 读取并转换为 OpenLayers 能识别的 Feature 实体，投影从 WGS84 转成 EPSG:3857

3️⃣ 样式定义：遮罩区域 + 多边形点位标注

const vectorLayer = new VectorLayer({source: turfSource,style: [new Style({fill: new Fill({ color: 'rgba(255,0,0,0.2)' }),stroke: new Stroke({ width: 2, color: 'blue' })}),new Style({image: new RegularShape({radius: 6,points: 4,rotation: Math.PI / 4,fill: new Fill({ color: 'white' }),stroke: new Stroke({ color: 'red', width: 2 })}),geometry: function (feature) {const coordinates = feature.getGeometry().getCoordinates()[0]return new MultiPoint(coordinates)}})]
})

外层填充透明红色，描边蓝色
顶点采用红白相间的矩形菱形样式标注（辅助观察）

🧪完整示例运行步骤

✅ 1. 安装依赖

npm install ol @turf/turf

✅ 2. 页面引入组件

将源码内容放置于 Vue 页面中（推荐 *.vue 文件中）

📦完整代码

<!--* @Author: 彭麒* @Date: 2025/7/14* @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]">Vue3中使用OpenLayers+Turf 实现遮罩布挖洞效果</div></div><div class="flex gap-2 mb-4 w-full justify-center"><el-button type="primary" size="small" @click="drawHole">绘制小洞</el-button><el-button type="primary" size="small" @click="drawMask">绘制遮罩布</el-button><el-button type="primary" size="small" @click="maskResult">合力遮罩打洞</el-button><el-button type="danger" size="small" @click="clearSource">清除图层</el-button></div><div id="vue-openlayers" ref="mapContainer"></div></div>
</template><script setup>
import 'ol/ol.css'
import { ref, onMounted } from 'vue'
import Map from 'ol/Map'
import View from 'ol/View'
import TileLayer from 'ol/layer/Tile'
import XYZ from 'ol/source/XYZ'
import VectorSource from 'ol/source/Vector'
import VectorLayer from 'ol/layer/Vector'
import GeoJSON from 'ol/format/GeoJSON'
import { Fill, Stroke, Style, RegularShape } from 'ol/style'
import { fromLonLat } from 'ol/proj'
import { MultiPoint } from 'ol/geom'
import * as turf from '@turf/turf'const map = ref(null)
const mapContainer = ref(null)const turfSource = new VectorSource({ wrapX: false })const holeData = [[[112, -21],[116, -36],[146, -39],[153, -24],[133, -10],[112, -21]]
]const maskData = [[[90, -55],[170, -55],[170, 10],[90, 10],[90, -55]]
]const show = (geojsonData) => {const features = new GeoJSON().readFeatures(geojsonData, {dataProjection: 'EPSG:4326',featureProjection: 'EPSG:3857',})turfSource.addFeatures(features)
}const clearSource = () => {turfSource.clear()
}const drawHole = () => {const hole = turf.polygon(holeData)show(hole)
}const drawMask = () => {const mask = turf.polygon(maskData)show(mask)
}const maskResult = () => {turfSource.clear()const hole = turf.polygon(holeData)const mask = turf.polygon(maskData)const masked = turf.mask(hole, JSON.parse(JSON.stringify(mask)))show(masked)
}const initMap = () => {const baseLayer = new TileLayer({source: new XYZ({url: 'http://wprd0{1-4}.is.autonavi.com/appmaptile?x={x}&y={y}&z={z}&lang=en&size=1&scl=1&style=7'})})const vectorLayer = new VectorLayer({source: turfSource,style: [new Style({fill: new Fill({ color: 'rgba(255,0,0,0.2)' }),stroke: new Stroke({ width: 2, color: 'blue' })}),new Style({image: new RegularShape({radius: 6,points: 4,rotation: Math.PI / 4,fill: new Fill({ color: 'white' }),stroke: new Stroke({ color: 'red', width: 2 })}),geometry: function (feature) {const coordinates = feature.getGeometry().getCoordinates()[0]return new MultiPoint(coordinates)}})]})map.value = new Map({target: mapContainer.value,layers: [baseLayer, vectorLayer],view: new View({projection: 'EPSG:3857',center: fromLonLat([146, -39]),zoom: 2})})
}onMounted(() => {initMap()
})
</script><style scoped>
.container {width: 840px;height: 570px;margin: 50px auto;border: 1px solid #42B983;
}#vue-openlayers {width: 800px;height: 400px;margin: 0 auto;border: 1px solid #42B983;position: relative;
}
</style>