Leaflet.heat

A fork of Leaflet.heat that allows for an additional field for positive and negative values, for e.g. a sentiment heatmap

Basic Usage

var heat = L.heatLayer([
	[50.5, 30.5, 0.2, 1], // lat, lng, intensity, layer (1 for positive, 0 for neutral, -1 for negative)
	[50.6, 30.4, 0.5, 0],
	[50.7, 30.3, 0.3, -1],
	...
], {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'}
• autoMax - automatically compute the max value based on the current map frame

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

0.1.1 — April 18, 2017

• Initial release.