2.5 KiB
Torque API
Torque provides two kinds of visulizations.
- static: provides a way to create heatmap like visualizations (note for Andrew: fon)
- dinamyc: animate points over a map (note for Andrew: Navy)
depending on the map provider you are using you need to use different layer type. Currently we provide layers for Google Maps and Leaflet.
L.TorqueLayer(options)
Arguments: * options: object that contains the following attributes: - user: cartodb username - table: table name - column: time column - countby: aggregation per pixel, e.g: 'count(cartodb_id)', - resolution: pixel resolution, - is_time: true or false, - steps: animation steps, e.g: 750, - blendmode: canvas blend mode 'lighter'
L.TorqueLayer.setKey(time: number)
Arguments * time: set time to be displayed. Should be a number between [0, steps)
L.TorqueLayer.setCartoCSS(cartocss: string)
Arguments
* cartocss: cartocss string that contains the point style. Torque does not support the full cartocss spec, only a small subset.
value
and zoom
variables can be used. value
is the value of aggregation (see countby
constructor option). zoom
is the current zoom being rendered
```
#layer {,
marker-fill: #662506;
marker-width: 20;
[value > 1] { marker-fill: #FEE391; }
[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; }
}
```
L.TiledTorqueLayer(options)
creates a static visualization Arguments: * options: - provider: 'url_template', - url: tile template url e.g 'http://host.com/{z}/{x}/{y}.json', (note to Andrew: link here to the json data format) - resolution: data resolution, e.g 4
L.TiledTorqueLayer.setKey(keys: number|array)
set keys to show, if it's an array all the keys in that array are accumulated
L.TiledTorqueLayer.setCartoCSS(cartocss: string)
value
and zoom
variables can be used. only polygon-fill
property is supported currently
Example:
#layer { polygon-fill: #FFFF00; [value >= 10] { polygon-fill: #FFCC00; } [value >= 100] { polygon-fill: #FF9900; } [value >= 1000] { polygon-fill: #FF6600; } [value >= 10000] { polygon-fill: #FF3300; } [value > 100000] { polygon-fill: #C00; } }