Leaflet multilayer example | CartoDB.js

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Leaflet multilayer example | CartoDB.js

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Last edited Jan 14, 2014

Created on Jan 7, 2014

A Leaflet map displays tornado data aggregated into hexagon bins at three distinct scales, with each bin labeled by its point count. The visualization uses CartoDB.js to run a SQL query that computes three nested hexagon grids, filtering points into large, medium, and small clusters based on density thresholds. A CartoDB sublayer applies CartoCSS to scale text sizes by cluster tier, overlaying the raw points with red labels on a Stamen toner base layer.

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