Add hexagon

The Hexagon Layer renders a hexagon heatmap based on an array of points. It takes the radius of hexagon bin, projects points into hexagon bins. The color and height of the hexagon is scaled by number of points it contains.

add_hexagon(
  map,
  data = get_map_data(map),
  polyline = NULL,
  lon = NULL,
  lat = NULL,
  layer_id = NULL,
  radius = 1000,
  elevation = NULL,
  elevation_function = c("sum", "mean", "min", "max"),
  colour = NULL,
  colour_function = c("sum", "mean", "min", "max"),
  legend = FALSE,
  legend_options = NULL,
  elevation_scale = 1,
  auto_highlight = FALSE,
  highlight_colour = "#AAFFFFFF",
  colour_range = NULL,
  update_view = TRUE,
  focus_layer = FALSE,
  digits = 6,
  transitions = NULL,
  brush_radius = NULL
)

Arguments

map	a mapdeck map object
data	data to be used in the layer. All coordinates are expected to be EPSG:4326 (WGS 84) coordinate system
polyline	column of data containing the polylines
lon	column containing longitude values
lat	column containing latitude values
layer_id	single value specifying an id for the layer. Use this value to distinguish between shape layers of the same type. Layers with the same id are likely to conflict and not plot correctly
radius	in metres. Default 1000
elevation	column containing the elevation of the value.
elevation_function	one of 'min', 'mean', 'max', 'sum'. IF supplied it specifies how the elevation values are calcualted. Defaults to sum.
colour	column containing numeric values to colour by.
colour_function	one of 'min', 'mean', 'max', 'sum'. If supplied it specifies how the colour values are calculated. Defaults to sum.
legend	logical indicating if a legend should be displayed
legend_options	A list of options for controlling the legend.
elevation_scale	value to sacle the elevations of the hexagons. Default 1
auto_highlight	logical indicating if the shape under the mouse should auto-highlight
highlight_colour	hex string colour to use for highlighting. Must contain the alpha component.
colour_range	vector of 6 hex colours
update_view	logical indicating if the map should update the bounds to include this layer
focus_layer	logical indicating if the map should update the bounds to only include this layer
digits	number of digits for rounding coordinates
transitions	list specifying the duration of transitions.
brush_radius	radius of the brush in metres. Default NULL. If supplied, the arcs will only show if the origin or destination are within the radius of the mouse. If NULL, all arcs are displayed

Details

add_hexagon supports POINT and MULTIPOINT sf objects

transitions

The transitions argument lets you specify the time it will take for the shapes to transition from one state to the next. Only works in an interactive environment (Shiny) and on WebGL-2 supported browsers and hardware.

The time is in milliseconds

Available transitions for hexagon

list( elevation = 0 colour = 0 )

data

If the data is a simple feature object, the geometry column is automatically detected. If the sf object contains more than one geometry column and you want to use a specific one, you'll need to set the active geometry using sf::st_geometry( x ) <- "your_column" , where "your_column" is the name of the column you're activating. See ?sf::st_geometry

Examples

if (FALSE) {

## You need a valid access token from Mapbox
key <- 'abc'
set_token( key )

df <- read.csv(paste0(
'https://raw.githubusercontent.com/uber-common/deck.gl-data/master/examples/'
, '3d-heatmap/heatmap-data.csv'
))

df <- df[!is.na(df$lng), ]

mapdeck( style = mapdeck_style("dark"), pitch = 45) %>%
add_hexagon(
  data = df
  , lat = "lat"
  , lon = "lng"
  , layer_id = "hex_layer"
  , elevation_scale = 100
)

library(sfheaders)
sf <- sfheaders::sf_point( df, x = "lng", y = "lat" )

mapdeck( style = mapdeck_style("dark"), pitch = 45 ) %>%
add_hexagon(
  data = sf
  , layer_id = "hex_layer"
  , elevation_scale = 100
)

## Using elevation and colour
df$colour <- rnorm(nrow(df))
df$elevation <- rnorm(nrow(df))

mapdeck( style = mapdeck_style("dark"), pitch = 45) %>%
add_hexagon(
  data = df
  , lat = "lat"
  , lon = "lng"
  , layer_id = "hex_layer"
  , elevation_scale = 100
  , elevation = "weight"
  , colour = "colour"
)

mapdeck( style = mapdeck_style("dark"), pitch = 45) %>%
add_hexagon(
  data = df
  , lat = "lat"
  , lon = "lng"
  , layer_id = "hex_layer"
  , elevation_scale = 100
  , elevation = "weight"
  , elevation_function = "mean"
  , colour = "colour"
  , colour_function = "mean"
)

## with a legend
df$val <- sample(1:10, size = nrow(df), replace = T)

mapdeck( style = mapdeck_style("dark"), pitch = 45) %>%
add_hexagon(
        data = df
        , lat = "lat"
        , lon = "lng"
        , layer_id = "hex_layer"
        , elevation_scale = 100
        , legend = T
        , legend_options = list( digits = 0 )
        , colour_function = "mean"
        , colour = "val"
)

}