我有一个带有数据地图的地球仪,我想在其中实现一点缩放功能。不缩放到特定国家,只是一个正常的缩放功能。
我应该在哪里寻找它?我是 d3 和数据图的新手。我设法或多或少地对其进行了自定义,但是仍然缺少此缩放功能。
这是代码笔: https ://codepen.io/simii/pen/yZvQmv
还有我的 javascript:
//basic map config with custom fills, mercator projection
var series = [
["USA",36.2],["GBR",7.4],["CAN",6.2],["DEU",5.7],["FRA", 4.1],["ESP",4.1],["ITA",3.3],["MEX",3.0],["AUS",2.5],["NLD",2.4],
["IND",2.1],["BRA",2.0],["GRC",1.4],["AUT",1.2],["ROU",1.2],["SRB",1.0],["COL",0.8],["POL",0.8],["ZAF",0.7],["SWE",0.7],
["DNK",0.6],["VEN",0.6],["JPN",0.6],["KOR",0.6],["BEL",0.5],["RUS",0.5],["PRT",0.5]
];
var dataset = {};
// We need to colorize every country based on "percent"
// colors should be uniq for every value.
// For this purpose we create palette(using min/max series-value)
var onlyValues = series.map(function(obj){ return obj[1]; });
var minValue = Math.min.apply(null, onlyValues),
maxValue = Math.max.apply(null, onlyValues);
// create color palette function
// color can be whatever you wish
var paletteScale = d3.scale.linear()
.domain([minValue,maxValue])
.range(["rgb(0,0,0)","rgb(219,219,219)"]); // color
// fill dataset in appropriate format
series.forEach(function(item){ //
// item example value ["USA", 36.2]
var iso = item[0],
value = item[1];
dataset[iso] = { percent: value, fillColor: paletteScale(value) };
});
var map;
var globalRotation = [90,-30];
function redraw() {
d3.select("#world").html('');
init();
}// redraw
function init() {
map = new Datamap({//need global var
scope: 'world',
element: document.getElementById('world'),
projection: 'orthographic',
projectionConfig: {
rotation: globalRotation
},
fills: {defaultFill: 'rgba(30,30,30,0.1)'},
data: dataset,
geographyConfig: {
responsive: true,
borderColor: 'rgba(222,222,222,0.2)',
highlightBorderWidth: 1,
// don't change color on mouse hover
highlightFillColor: function(geo) {
return geo['fillColor'] || 'rgba(30,30,30,0.5)';
},
// only change border
highlightBorderColor: 'rgba(222,222,222,0.5)',
// show desired information in tooltip
popupTemplate: function(geo, data) {
// don't show tooltip if country don't present in dataset
if (!data) { return ; }
// tooltip content
return ['',
'<div style="opacity:0.7;" class="hoverinfo">% of visitors in ' + geo.properties.name,
': ' + data.percent,
''].join('');
}
}
});
//draw a legend for this map
map.legend();
map.graticule();
var drag = d3.behavior.drag().on('drag', function() {
var dx = d3.event.dx;
var dy = d3.event.dy;
// var rotation = livemapScope.rotation;
var rotation = map.projection.rotate();
var radius = map.projection.scale();
var scale = d3.scale.linear()
.domain([-1 * radius, radius])
.range([-90, 90]);
var degX = scale(dx);
var degY = scale(dy);
rotation[0] += degX;
rotation[1] -= degY;
if (rotation[1] > 90) rotation[1] = 90;
if (rotation[1] < -90) rotation[1] = -90;
if (rotation[0] >= 180) rotation[0] -= 360;
globalRotation = rotation;
redraw();
})
d3.select("#world").select("svg").call(drag);
}// init
redraw();