How can I use a SVG image as layer on OpenLayers 4

问题:

I tried to adopt this approach based on ol.source.ImageStatic for OpenLayers 3 https://stackoverflow.com/a/36183738/2797243 to OpenLayers 4, with no result: https://codepen.io/itsonit/pen/jYKMMz?editors=0010

The current ol.source.ImageStatic example for OL4 you can find here: https://openlayers.org/en/latest/examples/static-image.html

How is it possible to load a SVG source to a OpenLayers 4 map?

回答1:

The functionality seems to depend on the SVG data.. A working example:

var svgComment = '<svg width="160" height="160" version="1.1" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 160 160" viewPort="0 0 160 160" class="svgClass">'
    + '<circle cx="30" cy="30" r="10" stroke="rgb(0, 191, 255)" stroke-width="1" fill="none" opacity="0.8">'
    + '<animate attributeType="CSS" attributeName="stroke-width" from="1" to="30" dur="0.5s" begin="0s" repeatCount="indefinite" />'
    + '<animate attributeType="CSS" attributeName="opacity" from="0.8" to="0.2" dur="0.5s" begin="0s" repeatCount="indefinite" />'
    + '</circle>'
    + '<circle cx="30" cy="30" r="10" fill="rgba(0,0,0,0.8)">'
    + '</circle>'
    + '</svg>';


//Test SVG
//var img = document.createElement('img');
//img.src=src;
//document.body.append(img);

 var commentStyle =  new ol.style.Style({
    image: new ol.style.Icon({
      src: 'data:image/svg+xml;charset=utf-8,' + encodeURIComponent(svgComment)
    })
  });

var vectorSource = new ol.source.Vector({
  features: [
      new ol.Feature({
        geometry: new ol.geom.Point([0, 0])
      }) 
  ]
});

var vectorLayer = new ol.layer.Vector({
  name: 'Comments',
  style: commentStyle,
  source: vectorSource
});

//display the map
var rasterLayer = new ol.layer.Tile({
  source: new ol.source.TileJSON({
    url: 'https://api.tiles.mapbox.com/v3/mapbox.geography-class.json?secure',
    crossOrigin: ''
  })
});

var map = new ol.Map({
  layers: [rasterLayer, vectorLayer],
  target: document.getElementById('map'),
  view: new ol.View({
    center: [0, 0],
    zoom: 3
  })
});

<script src="https://openlayers.org/en/v4.6.4/build/ol.js"></script>
<div id="map" class="map"></div>