3.3 KiB
Torque
Render big, timeseries data in the client. Uses CartoDB to generate a datacube format. For a brief introduction to the format and methods, see our presentation slides
CartoDB users can use this code right away. Specify your username/tablename and datecolumn to get mapping time immediatley.
Have fun!
- Play with your own data: http://cartodb.github.com/torque/
- The Guardian's Data Blog write-up of Royal Navy ships in WWI: http://www.guardian.co.uk/news/datablog/interactive/2012/oct/01/first-world-war-royal-navy-ships-mapped
- A car in Nürburgring track: http://cartodb.github.com/torque/examples/car.html
Torque library reference
Torque lets you render big, timeseries or categorical data in the client. This is useful for many modern applications that need more than just a static map. Early versions of Torque have been used to visualize human movement, Twitter activity, biodiversity data, and many more large-scale datasets.
The library uses CartoDB to generate a layercube format. For a brief introduction to the format and methods, see our presentation slides. If you are not using CartoDB to host your data, you can modify the input parameters to point toward any layercube service.
Getting started
The simplest way to use a visualization with Torque is...
Create a simple Torque visualization
...
<body>
<div id="map"></div>
...
<script>
// define the torque layer style using cartocss
var CARTOCSS = [
'Map {',
'-torque-time-attribute: "date";',
'-torque-aggregation-function: "count(cartodb_id)";',
'-torque-frame-count: 760;',
'-torque-animation-duration: 15;',
'-torque-resolution: 2',
'}',
'#layer {',
' marker-width: 3;',
' marker-fill-opacity: 0.8;',
' marker-fill: #FEE391; ',
' comp-op: "lighten";',
' [value > 2] { marker-fill: #FEC44F; }',
' [value > 3] { marker-fill: #FE9929; }',
' [value > 4] { marker-fill: #EC7014; }',
' [value > 5] { marker-fill: #CC4C02; }',
' [value > 6] { marker-fill: #993404; }',
' [value > 7] { marker-fill: #662506; }',
' [frame-offset = 1] { marker-width: 10; marker-fill-opacity: 0.05;}',
' [frame-offset = 2] { marker-width: 15; marker-fill-opacity: 0.02;}',
'}'
].join('\n');
var map = new L.Map('map', {
zoomControl: true,
center: [40, 0],
zoom: 3
});
L.tileLayer('http://{s}.api.cartocdn.com/base-dark/{z}/{x}/{y}.png', {
attribution: 'CartoDB'
}).addTo(map);
var torqueLayer = new L.TorqueLayer({
user : 'viz2',
table : 'ow',
cartocss: CARTOCSS
});
torqueLayer.addTo(map);
torqueLayer.play()
</script>
</body>
Grab the complete example source code