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@ramiroaznar
Last active July 28, 2017 13:19
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Change map projections from two layers with CARTO.js
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>Change Map Projections</title>
<meta name="description" content="">
<meta name="author" content="">
<meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1">
<link rel="stylesheet" href="https://cartodb-libs.global.ssl.fastly.net/cartodb.js/v3/3.15/themes/css/cartodb.css" />
<script src="https://cartodb-libs.global.ssl.fastly.net/cartodb.js/v3/3.15/cartodb.js"></script>
<link href="https://cdnjs.cloudflare.com/ajax/libs/select2/4.0.3/css/select2.min.css" rel="stylesheet" />
<script src="https://cdnjs.cloudflare.com/ajax/libs/select2/4.0.3/js/select2.min.js"></script>
<style>
html, body, #map {
height: 100%;
padding: 0;
margin: 0;
background-color: #B8D0CB;
}
#wraper-prj-selector {
position: absolute;
top: 20px;
right: 20px;
}
.js-prj-selector {
width: 240px;
}
</style>
</head>
<body>
<div id="map"></div>
<div id="wraper-prj-selector">
<select class="js-prj-selector">
<option value="#" selected disabled>Select a map projection</option>
</select>
</div>
<script type="text/javascript">
function main() {
var selector = $(".js-prj-selector");
var map = L.map('map', {
center: [40, 0],
zoom: 3
});
cartodb.createLayer(map, {
user_name: 'ramirocartodb',
type: 'cartodb',
sublayers: [{
sql: 'select * from ne_50m_land',
cartocss: '#layer{polygon-fill: #98B087;}'
},
{
sql: 'select * from populated_places',
cartocss: '#layer{dot-fill: white; dot-width: 2}'
}]
}, { https: true })
.addTo(map)
.done(function(layer) {
var land = layer.getSubLayer(0),
cities = layer.getSubLayer(1);
var sql = new cartodb.SQL({ user: 'ramirocartodb' });
sql.execute("SELECT * FROM ramirocartodb.map_projs ORDER BY auth_srid")
.done(function(data) {
var srids = data.rows;
_.each(srids, function(srid, index, srids){
selector.append("<option value=" + srid['auth_srid'] + ">" + srid['geogcs'] + "</option>");
})
selector.select2();
});
selector.change(function(){
var input = $( ".js-prj-selector option:selected" ).val();
land.setSQL("SELECT cartodb_id, st_transform(the_geom, " + input + ") as the_geom_webmercator FROM ne_50m_land");
cities.setSQL("SELECT cartodb_id, st_transform(the_geom, " + input + ") as the_geom_webmercator FROM populated_places");
});
});
}
window.onload = main;
</script>
</body>
</html>
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