Skip to content

Instantly share code, notes, and snippets.

@mbostock
Last active November 10, 2018 22:25
  • Star 1 You must be signed in to star a gist
  • Fork 1 You must be signed in to fork a gist
Star You must be signed in to star a gist
Save mbostock/625531 to your computer and use it in GitHub Desktop.
Resizable Markers
license: gpl-3.0

A quick example demonstrating the use of "show" event handlers and reshow, which allows you to restyle GeoJSON features dynamically from an external event. In this example, you can use the jQuery UI slider in the top-left corner to resize the points.

<!DOCTYPE html>
<html>
<head>
<script type="text/javascript" src="https://cdn.rawgit.com/simplegeo/polymaps/v2.3.0/polymaps.min.js"></script>
<script type="text/javascript" src="https://cdn.rawgit.com/simplegeo/polymaps/v2.3.0/lib/crimespotting/crimespotting.js"></script>
<script type="text/javascript" src="https://cdn.rawgit.com/protovis/protovis/v3.3.1/examples/jquery-1.4.2.min.js"></script>
<script type="text/javascript" src="https://cdn.rawgit.com/protovis/protovis/v3.3.1/examples/slider/jquery-ui-1.8rc3.custom.min.js"></script>
<style type="text/css">
@import url("https://cdn.rawgit.com/simplegeo/polymaps/v2.3.0/examples/example.css");
@import url("https://cdn.rawgit.com/protovis/protovis/v3.3.1/examples/slider/ui-lightness/jquery-ui-1.8rc3.custom.css");
html, body {
height: 100%;
background: #E6E6E6;
}
svg {
display: block;
}
.layer circle {
fill: lightcoral;
fill-opacity: .5;
stroke: brown;
}
#slider {
position: absolute;
top: 10px;
left: 10px;
width: 300px;
height: 20px;
display: block;
background: #ccc;
}
.ui-slider {
font-size: 10px;
margin-top: 5px;
}
.ui-state-focus {
outline: none;
}
</style>
</head>
<body>
<script type="text/javascript">
var po = org.polymaps;
var r = 4.5;
var map = po.map()
.container(document.body.appendChild(po.svg("svg")))
.center({lat: 37.787, lon: -122.228})
.zoomRange([10, 16])
.add(po.interact());
map.add(po.image()
.url(po.url("http://{S}tile.cloudmade.com"
+ "/1a1b06b230af4efdbb989ea99e9841af" // http://cloudmade.com/register
+ "/998/256/{Z}/{X}/{Y}.png")
.hosts(["a.", "b.", "c.", ""])));
map.add(geoJson = po.geoJson()
.url(crimespotting("http://oakland.crimespotting.org"
+ "/crime-data"
+ "?count=100"
+ "&format=json"
+ "&bbox={B}"
+ "&dstart=2010-04-01"
+ "&dend=2010-04-01"))
.on("show", show)
.clip(false)
.scale("fixed")
.zoom(12));
/* Resize the GeoJSON points! */
function show(e) {
for (var i = 0; i < e.features.length; i++) {
e.features[i].element.setAttribute("r", r);
}
}
</script>
<div id="slider"></div>
<script type="text/javascript">
$("#slider").slider({
min: 0, max: 1000, value: r * r, slide: function(e, ui) {
r = Math.sqrt(ui.value);
geoJson.reshow();
}
});
</script>
<span id="copy">
&copy; 2010
<a href="http://www.cloudmade.com/">CloudMade</a>,
<a href="http://www.openstreetmap.org/">OpenStreetMap</a> contributors,
<a href="http://creativecommons.org/licenses/by-sa/2.0/">CCBYSA</a>.
</span>
</body>
</html>
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment