mapgl (version 0.1.3)

add_heatmap_layer: Add a heatmap layer to a Mapbox GL map

Description

Add a heatmap layer to a Mapbox GL map

Usage

add_heatmap_layer(
  map,
  id,
  source,
  source_layer = NULL,
  heatmap_color = NULL,
  heatmap_intensity = NULL,
  heatmap_opacity = NULL,
  heatmap_radius = NULL,
  heatmap_weight = NULL,
  visibility = "visible",
  slot = NULL,
  min_zoom = NULL,
  max_zoom = NULL,
  before_id = NULL,
  filter = NULL
)

Value

The modified map object with the new heatmap layer added.

Arguments

map

A map object created by the mapboxgl function.

id

A unique ID for the layer.

source

The ID of the source, alternatively an sf object (which will be converted to a GeoJSON source) or a named list that specifies type and url for a remote source.

source_layer

The source layer (for vector sources).

heatmap_color

The color of the heatmap points.

heatmap_intensity

The intensity of the heatmap points.

heatmap_opacity

The opacity of the heatmap layer.

heatmap_radius

The radius of influence of each individual heatmap point.

heatmap_weight

The weight of each individual heatmap point.

visibility

Whether this layer is displayed.

slot

An optional slot for layer order.

min_zoom

The minimum zoom level for the layer.

max_zoom

The maximum zoom level for the layer.

before_id

The name of the layer that this layer appears "before", allowing you to insert layers below other layers in your basemap (e.g. labels).

filter

An optional filter expression to subset features in the layer.

Examples

if (FALSE) {
library(mapgl)

mapboxgl(
    style = mapbox_style("dark"),
    center = c(-120, 50),
    zoom = 2
) |>
    add_heatmap_layer(
        id = "earthquakes-heat",
        source = list(
            type = "geojson",
            data = "https://docs.mapbox.com/mapbox-gl-js/assets/earthquakes.geojson"
        ),
        heatmap_weight = interpolate(
            column = "mag",
            values = c(0, 6),
            stops = c(0, 1)
        ),
        heatmap_intensity = interpolate(
            property = "zoom",
            values = c(0, 9),
            stops = c(1, 3)
        ),
        heatmap_color = interpolate(
            property = "heatmap-density",
            values = seq(0, 1, 0.2),
            stops = c(
                "rgba(33,102,172,0)", "rgb(103,169,207)",
                "rgb(209,229,240)", "rgb(253,219,199)",
                "rgb(239,138,98)", "rgb(178,24,43)"
            )
        ),
        heatmap_opacity = 0.7
    )
}