Skip to contents

View an H3 hexagonal-binning PMTiles archive

Source: R/freestile_h3.R
view_h3_tiles.Rd

Reads the metadata from a PMTiles archive produced by freestile_h3() and builds a mapgl map with one fill layer per H3 resolution plus a circle layer for raw points. Automatically detects whether the archive was built with fade = FALSE (disjoint zoom windows, clean breaks) or fade = TRUE (overlapping windows, cross-fade) and styles accordingly.

Usage

view_h3_tiles(
  input,
  agg_column = NULL,
  stops = NULL,
  palette = "viridis",
  hex_opacity = 0.9,
  point_color = "#0868ac",
  point_radius = NULL,
  background_style = NULL,
  hex_layer_prefix = "h3",
  point_layer_name = "points",
  port = 8080
)

Arguments

input

Path to a local .pmtiles file produced by freestile_h3().

agg_column

Character or NULL. Aggregation column to drive the hex color scale. If NULL, the first non-h3_id numeric field in the metadata is used.

stops

List with values and colors (equal length, sorted by values) defining the shared color scale across all hex layers. If NULL, the documented quick-look default is used.

palette

Character. Named palette used to generate default colors when stops is NULL. Currently supports "viridis" (default), "magma", "plasma", "cividis", "inferno", "rocket", "mako", "turbo" if viridisLite is installed; otherwise falls back to a five-color blue ramp.

hex_opacity

Numeric. Peak fill opacity for hex layers (default 0.9). In fade mode this is the opacity at each layer's center zoom.

point_color

Character. Color for the raw-point circles (default "#0868ac").

point_radius

mapgl expression or NULL. If NULL, a zoom-interpolated default is used.

background_style

mapgl style passed to mapgl::maplibre(); if NULL uses mapgl::maplibre() defaults.

hex_layer_prefix

Character. Prefix used when the archive was written. Must match the value passed to freestile_h3(); default "h3".

point_layer_name

Character. Name of the raw-points MVT layer in the archive. Must match the value passed to freestile_h3(); default "points".

port

Integer. Port for the local PMTiles server (default 8080).

Value

A mapgl map object.

Details

The default color scale is a documented quick-look ramp (5 evenly spaced breaks across 1, 10, 100, 1000, 10000). For production maps, pass an explicit stops = list(values = ..., colors = ...) derived from your data. Embedding real aggregation statistics in PMTiles metadata is on the roadmap.

See also

freestile_h3(), view_tiles()

Examples

if (FALSE) { # \dontrun{
view_h3_tiles("wind.pmtiles", agg_column = "n",
  stops = list(values = c(1, 10, 100, 1000, 10000),
               colors = viridisLite::viridis(5)))
} # }