八章-93-投影成摩尔威德球体
2020-03-27 本文已影响0人
彩云飘过
本文基于腾讯课堂老胡的课《跟我学Openlayers--基础实例详解》做的学习笔记，使用的openlayers 5.3.x api。
源码 见 1093.html ，对应的 官网示例
image.png
<!DOCTYPE html>
<html>
<head>
<title></title>
<link rel="stylesheet" href="../include/ol.css" type="text/css" />
<script src="../include/ol.js"></script>
<script src="../include/proj4.js"></script>
</head>
<style></style>
<body>
<div id="map" class="map"></div>
<script>
proj4.defs('ESRI:53009', '+proj=moll +lon_0=0 +x_0=0 +y_0=0 +a=6371000 ' +
'+b=6371000 +units=m +no_defs');
ol.proj.proj4.register(proj4);
// Configure the Sphere Mollweide projection object with an extent,
// and a world extent. These are required for the Graticule.
var sphereMollweideProjection = new ol.proj.Projection({
code: 'ESRI:53009',
extent: [-9009954.605703328, -9009954.605703328,
9009954.605703328, 9009954.605703328],
worldExtent: [-179, -89.99, 179, 89.99]
});
var map = new ol.Map({
keyboardEventTarget: document,
layers: [
new ol.layer.Vector({
source: new ol.source.Vector({
url: '../data/countries-110m.geojson',
format: new ol.format.GeoJSON()
})
})
],
target: 'map',
view: new ol.View({
center: [0, 0],
projection: sphereMollweideProjection,
resolutions: [65536, 32768, 16384, 8192, 4096, 2048],
zoom: 0
})
});
new ol.Graticule({
map: map
});
</script>
</body>
</html>
