<!DOCTYPE html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<meta name="viewport" content="initial-scale=1.0, user-scalable=no" />
<title>CanvasLayer</title>
<!-- <script type="text/javascript" src="http://api.map.baidu.com/api?v=3.0&ak=你的祕鑰"></script> -->
<script type="text/javascript" src="http://api.map.baidu.com/api?v=1.2"></script>
<script type="text/javascript" src="./Heatmap_min.js"></script>
<style type="text/css">
body, html,#container {width: 100%;height: 100%;overflow: hidden;margin:0;font-family:"微軟雅黑";}
</style>
</head>
<body>
<div id="container"></div>
</body>
</html>
<script src="https://cdn.bootcss.com/jquery/3.3.1/jquery.min.js"></script>
<script type="text/javascript">
var map = new BMap.Map("container",{minZoom:5,maxZoom:12});
var point = new BMap.Point(113.93473, 22.54302);
map.centerAndZoom(point, 18); // 初始化地圖，設置中心點座標和地圖級別
map.enableScrollWheelZoom(); // 允許滾輪縮放
if(!isSupportCanvas()){
alert('熱力圖目前只支持有canvas支持的瀏覽器,您所使用的瀏覽器不能使用熱力圖功能~')
}
//詳細的參數,可以查看heatmap.js的文檔 https://github.com/pa7/heatmap.js/blob/master/README.md
//參數說明如下:
/* visible 熱力圖是否顯示,默認爲true
* opacity 熱力的透明度,1-100
* radius 勢力圖的每個點的半徑大小
* gradient {JSON} 熱力圖的漸變區間 . gradient如下所示
* {
.2:'rgb(0, 255, 255)',
.5:'rgb(0, 110, 255)',
.8:'rgb(100, 0, 255)'
}
其中 key 表示插值的位置, 0~1.
value 爲顏色值.
*/
// var points = JSON.parse(data).list;
var points = [
{"lng": 116.895579, "lat": 24.306521,"count":84500},
{"lng": 113.951068, "lat": 22.772504,"count":6200},
{"lng": 110.00006, "lat": 40.603564,"count":23000},
{"lng": 111.846788, "lat": 21.897821,"count":11000}
]
heatmapOverlay = new BMapLib.HeatmapOverlay({"radius":20});
map.addOverlay(heatmapOverlay);
heatmapOverlay.setDataSet({data:points,max:5000});
//是否顯示熱力圖
function openHeatmap(){
heatmapOverlay.show();
}
function closeHeatmap(){
heatmapOverlay.hide();
}
closeHeatmap();
function setGradient(){
/*格式如下所示:
{
0:'rgb(102, 255, 0)',
.5:'rgb(255, 170, 0)',
1:'rgb(255, 0, 0)'
}*/
var gradient = {};
var colors = document.querySelectorAll("input[type='color']");
colors = [].slice.call(colors,0);
colors.forEach(function(ele){
gradient[ele.getAttribute("data-key")] = ele.value;
});
heatmapOverlay.setOptions({"gradient":gradient});
}
//判斷瀏覽區是否支持canvas
function isSupportCanvas(){
var elem = document.createElement('canvas');
return !!(elem.getContext && elem.getContext('2d'));
}
openHeatmap();
</script>