Leaflet.heat

A tiny, simple and fast Leaflet heatmap plugin. Uses simpleheat under the hood, additionally clustering points into a grid for performance.

Demos

• 10,000 points →
• Adding points dynamically →

Basic Usage

var heat = L.heatLayer([
	[50.5, 30.5, 0.2], // lat, lng, intensity
	[50.6, 30.4, 0.5],
	...
], {radius: 25}).addTo(map);

To include the plugin, just use leaflet-heat.js from the dist folder:

<script src="leaflet-heat.js"></script>

Building

To build the dist files run: npm install && npm run prepublish

Reference

L.heatLayer(latlngs, options)

Constructs a heatmap layer given an array of points and an object with the following options:

• minOpacity - the minimum opacity the heat will start at
• maxZoom - zoom level where the points reach maximum intensity (as intensity scales with zoom), equals maxZoom of the map by default
• max - maximum point intensity, 1.0 by default
• radius - radius of each "point" of the heatmap, 25 by default
• blur - amount of blur, 15 by default
• gradient - color gradient config, e.g. {0.4: 'blue', 0.65: 'lime', 1: 'red'}
• transformer - a function which is applied to the point intensities, (x) => x by default, but it can be (x) => Math.log(x) for example

Each point in the input array can be either an array like [50.5, 30.5, 0.5], or a Leaflet LatLng object.

Optional third argument in each LatLng point (altitude) represents point intensity. Unless max option is specified, intensity should range between 0.0 and 1.0.

Methods

• setOptions(options): Sets new heatmap options and redraws it.
• addLatLng(latlng): Adds a new point to the heatmap and redraws it.
• setLatLngs(latlngs): Resets heatmap data and redraws it.
• redraw(): Redraws the heatmap.

Changelog

0.2.0 — Oct 26, 2015

• Fixed intensity to work properly with max option.
• Fixed zoom animation on Leaflet 1.0 beta 2.
• Fixed tiles and point intensity in demos.

0.1.3 — Nov 25, 2015

• Fixed some edge cases when handling point intensity.
• Added minOpacity option.

0.1.2 — Nov 5, 2014

• Added compatibility with Leaflet 0.8-dev.

0.1.1 — Apr 22, 2014

• Fixed overlaying two heatmaps on top of each other.
• Fixed rare animation issues.

0.1.0 — Feb 3, 2014

• Added addLatLng, setLatlngs, setOptions and redraw methods.
• Added max option and support for different point intensity values (through LatLng third argument).
• Added gradient option to customize colors.

0.0.1 — Jan 31, 2014

• Initial release.