Google Map API v3 对除多边形外的所有内容进行着色 [英] Google Map API v3 shade everything EXCEPT for polygon

问题描述

所以到目前为止，我们已经熟悉使用 v3 API 向 Google 地图添加形状:

$j('#map').gmap('addShape', 'Circle', {'strokeWeight': 0,'fillColor': "#008595",'fillOpacity':0.25，中心":结果[0].geometry.location，半径":1500，可点击":假});

上面的代码将创建一个圆圈并用填充 #008595 对其进行着色.有没有办法对地图进行反向着色?我希望整个世界都以半不透明度着色/填充，除了我的标记所在的洞.可能吗?

解决方案

你需要定义一个覆盖整个世界并且里面有一个洞的多边形，你不能用Circle"来实现或矩形"形状，它必须是具有(至少)两条路径的多边形.

相关问题:

• 更改 Google 圈外的地图不透明度Maps JavaScript API v3
• 使用 Google 突出显示多边形并为地图的其余部分着色地图

代码片段:

//本例在地图上创建圆圈，代表//美国的人口.//首先，为每个城市创建一个包含 LatLng 和人口的对象.var citymap = {};城市地图['芝加哥'] = {中心:新的 google.maps.LatLng(41.878113, -87.629798)，人口:2842518};城市地图['纽约'] = {中心:新的 google.maps.LatLng(40.714352, -74.005973)，人口:8143197};城市地图['洛杉矶'] = {中心:新的 google.maps.LatLng(34.052234, -118.243684)，人口:3844829};var cityCircle;var bounds = new google.maps.LatLngBounds();函数drawCircle(点，半径，目录){var d2r = Math.PI/180;//度数到弧度var r2d = 180/Math.PI;//弧度到度变量地球半径 = 3963;//3963 是以英里为单位的地球半径无功点 = 32;//在纬度/经度中找到raidusvar rlat =(半径/地球半径)* r2d；var rlng = rlat/Math.cos(point.lat() * d2r);var extp = new Array();如果(目录== 1){无功开始= 0;var 结束 = 点数 + 1}//这里额外的一项确保我们连接两端别的 {var start = 点数 + 1;无功结束 = 0}for (var i = start;(dir == 1 ? i < end : i > end);i = i + 目录) {var theta = Math.PI * (i/(points/2));ey = point.lng() + (rlng * Math.cos(theta));//中心 a + 半径 x * cos(theta)ex = point.lat() + (rlat * Math.sin(theta));//中心 b + 半径 y * sin(theta)extp.push(new google.maps.LatLng(ex, ey));bounds.extend(extp[extp.length - 1]);}返回 ext;}函数初始化(){//创建地图.var mapOptions = {缩放:4，中心:新的 google.maps.LatLng(37.09024, -95.712891)，mapTypeId: google.maps.MapTypeId.TERRAIN};var map = new google.maps.Map(document.getElementById('map-canvas'),地图选项);var 外界 = [新的 google.maps.LatLng(85, 180),新的 google.maps.LatLng(85, 90),新的 google.maps.LatLng(85, 0),新的 google.maps.LatLng(85, -90),新的 google.maps.LatLng(85, -180),新的 google.maps.LatLng(0, -180),新的 google.maps.LatLng(-85, -180),新的 google.maps.LatLng(-85, -90),新的 google.maps.LatLng(-85, 0),新的 google.maps.LatLng(-85, 90),新的 google.maps.LatLng(-85, 180),新的 google.maps.LatLng(0, 180),新的 google.maps.LatLng(85, 180)];var 人口选项 = {中风颜色:'#FF0000'，中风不透明度:0.8，行程重量:2，填充颜​​色:'#FF0000'，填充不透明度:0.35，地图:地图，路径:[outerbounds, drawCircle(citymap['newyork'].center, 10, -1)]};//将这个城市的圆圈添加到地图上.cityCircle = new google.maps.Polygon(populationOptions);map.fitBounds(bounds);}google.maps.event.addDomListener(window, 'load', initialize);

html,身体，#地图画布{高度:100%；边距:0px；填充:0px}

<script src="https://maps.googleapis.com/maps/api/js?key=AIzaSyCkUOdZ5y7hMm0yrcCQoCvLwzdM6M8s5qk"></脚本><div id="map-canvas"></div>

So by now we're familiar with adding shapes to a Google map with the v3 API:

$j('#map').gmap('addShape', 'Circle', { 
    'strokeWeight': 0, 
    'fillColor': "#008595", 
    'fillOpacity': 0.25, 
    'center': result[0].geometry.location, 
    'radius': 1500, 
    'clickable': false 
});

The above code will create a circle and shade it with fill #008595. Is there any way to inversely shade a map? I would like the entire world to be shaded/filled at half opacity except for a hole where my markers are. Possible?

解决方案

you need to define a polygon that covers the whole world and has a hole in it, you can't do it with the "Circle" or "Rectangle" shapes, it has to be a polygon with (at least) two paths.

here is an example

related questions:

• Change map opacity outside circle of Google Maps JavaScript API v3
• Highlight polygon and tint rest of map using Google Maps

code snippet:

// This example creates circles on the map, representing
// populations in the United States.

// First, create an object containing LatLng and population for each city.
var citymap = {};
citymap['chicago'] = {
  center: new google.maps.LatLng(41.878113, -87.629798),
  population: 2842518
};
citymap['newyork'] = {
  center: new google.maps.LatLng(40.714352, -74.005973),
  population: 8143197
};
citymap['losangeles'] = {
  center: new google.maps.LatLng(34.052234, -118.243684),
  population: 3844829
};
var cityCircle;
var bounds = new google.maps.LatLngBounds();

function drawCircle(point, radius, dir) {
  var d2r = Math.PI / 180; // degrees to radians 
  var r2d = 180 / Math.PI; // radians to degrees 
  var earthsradius = 3963; // 3963 is the radius of the earth in miles
  var points = 32;

  // find the raidus in lat/lon 
  var rlat = (radius / earthsradius) * r2d;
  var rlng = rlat / Math.cos(point.lat() * d2r);

  var extp = new Array();
  if (dir == 1) {
    var start = 0;
    var end = points + 1
  } // one extra here makes sure we connect the ends
  else {
    var start = points + 1;
    var end = 0
  }
  for (var i = start;
    (dir == 1 ? i < end : i > end); i = i + dir) {
    var theta = Math.PI * (i / (points / 2));
    ey = point.lng() + (rlng * Math.cos(theta)); // center a + radius x * cos(theta) 
    ex = point.lat() + (rlat * Math.sin(theta)); // center b + radius y * sin(theta) 
    extp.push(new google.maps.LatLng(ex, ey));
    bounds.extend(extp[extp.length - 1]);
  }
  return extp;
}

function initialize() {
  // Create the map.
  var mapOptions = {
    zoom: 4,
    center: new google.maps.LatLng(37.09024, -95.712891),
    mapTypeId: google.maps.MapTypeId.TERRAIN
  };

  var map = new google.maps.Map(document.getElementById('map-canvas'),
    mapOptions);

  var outerbounds = [
    new google.maps.LatLng(85, 180),
    new google.maps.LatLng(85, 90),
    new google.maps.LatLng(85, 0),
    new google.maps.LatLng(85, -90),
    new google.maps.LatLng(85, -180),
    new google.maps.LatLng(0, -180),
    new google.maps.LatLng(-85, -180),
    new google.maps.LatLng(-85, -90),
    new google.maps.LatLng(-85, 0),
    new google.maps.LatLng(-85, 90),
    new google.maps.LatLng(-85, 180),
    new google.maps.LatLng(0, 180),
    new google.maps.LatLng(85, 180)
  ];
  var populationOptions = {
    strokeColor: '#FF0000',
    strokeOpacity: 0.8,
    strokeWeight: 2,
    fillColor: '#FF0000',
    fillOpacity: 0.35,
    map: map,
    paths: [outerbounds, drawCircle(citymap['newyork'].center, 10, -1)]
  };
  // Add the circle for this city to the map.
  cityCircle = new google.maps.Polygon(populationOptions);
  map.fitBounds(bounds);
}

google.maps.event.addDomListener(window, 'load', initialize);

html,
body,
#map-canvas {
  height: 100%;
  margin: 0px;
  padding: 0px
}

<script src="https://maps.googleapis.com/maps/api/js?key=AIzaSyCkUOdZ5y7hMm0yrcCQoCvLwzdM6M8s5qk"></script>
<div id="map-canvas"></div>

这篇关于Google Map API v3 对除多边形外的所有内容进行着色的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！