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 1020.html ，对应的 官网示例 https://openlayers.org/en/latest/examples/zoomslider.html?q=ZoomSlider
image.png
image.png
<!DOCTYPE html>
<html>
<head>
<title></title>
<link rel="stylesheet" href="../include/ol.css" type="text/css" />
<script src="../include/ol.js"></script>
</head>
<body>
<div id="map" class="map"></div>
<script>
var stroke = new ol.style.Stroke({ color: "black", width: 2 });
var fill = new ol.style.Fill({ color: "red" });
var styles = {
square: new ol.style.Style({
image: new ol.style.RegularShape({
fill: fill,
stroke: stroke,
points: 4,
radius: 10,
angle: Math.PI / 4
})
}),
triangle: new ol.style.Style({
image: new ol.style.RegularShape({
fill: fill,
stroke: stroke,
points: 3,
radius: 10,
rotation: Math.PI / 4,
angle: 0
})
}),
star: new ol.style.Style({
image: new ol.style.RegularShape({
fill: fill,
stroke: stroke,
points: 5,
radius: 10,
radius2: 4,
angle: 0
})
}),
cross: new ol.style.Style({
image: new ol.style.RegularShape({
fill: fill,
stroke: stroke,
points: 4,
radius: 10,
radius2: 0,
angle: 0
})
}),
x: new ol.style.Style({
image: new ol.style.RegularShape({
fill: fill,
stroke: stroke,
points: 4,
radius: 10,
radius2: 0,
angle: Math.PI / 4
})
})
};
var styleKeys = ["x", "cross", "star", "triangle", "square"];
//随机生成250个点的坐标，为每个坐标设置样式，样式时常规形状
var count = 250;
var features = new Array(count);
var e = 4500000;
for (var i = 0; i < count; ++i) {
var coordinates = [
2 * e * Math.random() - e,
2 * e * Math.random() - e
];
features[i] = new ol.Feature(new ol.geom.Point(coordinates));
features[i].setStyle(styles[styleKeys[Math.floor(Math.random() * 5)]]);
}
var source = new ol.source.Vector({
features: features
});
var vectorLayer = new ol.layer.Vector({
source: source
});
var map = new ol.Map({
layers: [vectorLayer],
target: "map",
view: new ol.View({
center: [0, 0],
zoom: 2
})
});
</script>
</body>
</html>
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