R/map_layer_column.R

In SymbolixAU/mapdeck: Interactive Maps Using 'Mapbox GL JS' and 'Deck.gl'

mapdeckColumnDependency <- function() {
	list(
		createHtmlDependency(
			name = "column",
			version = "1.0.0",
			src = system.file("htmlwidgets/lib/column", package = "mapdeck"),
			script = c("column.js"),
			all_files = FALSE
		)
	)
}


#' Add column
#'
#'The ColumnLayer can be used to render a heatmap of vertical cylinders. It renders
#'a tesselated regular polygon centered at each given position (a "disk"), and extrude it in 3d.
#'
#' @inheritParams add_polygon
#' @param lon column containing longitude values
#' @param lat column containing latitude values
#' @param polyline column of \code{data} containing the polylines
#' @param disk_resolution The number of sides to render the disk as.
#' The disk is a regular polygon that fits inside the given radius.
#' A higher resolution will yield a smoother look close-up, but also requires more resources to render.
#' @param radius in metres. Default 1000
#' @param angle disk rotation, counter-clockwise, in degrees
#' @param coverage radius multiplier, in range [0,1]. The radius of the disk is calcualted
#' by coverage * radius
#' @param elevation_scale value to scale the elevations of the columns Default 1
#'
#' @inheritSection add_polygon data
#' @inheritSection add_arc legend
#' @inheritSection add_arc id
#'
#' @examples
#' \dontrun{
#'
#' ## You need a valid access token from Mapbox
#' key <- 'abc'
#' set_token( key )
#'
#'
#' df <- capitals
#' df$elev <- sample(50000:500000, size = nrow(df), replace = TRUE)
#'
#' mapdeck(style = mapdeck_style("dark"), pitch = 45) %>%
#' add_column(
#'   data = df
#'   , lat = "lat"
#'   , lon = "lon"
#'   , elevation = "elev"
#'   , fill_colour = "lon"
#'   , disk_resolution = 20
#'   , radius = 100000
#'   , tooltip = "capital"
#' )
#'
#' library(sfheaders)
#' sf <- sfheaders::sf_point( df, x = "lon", y = "lat" )
#'
#' sf$elev <- df$elev
#'
#' mapdeck( style = mapdeck_style("dark"), pitch = 45 ) %>%
#' add_column(
#'   data = sf
#'   , layer_id = "col_layer"
#'   , elevation = "elev"
#'   , radius = 100000
#'   , fill_colour = "country"
#' )
#'
#'
#' }
#'
#' @details
#'
#' \code{add_column} supports POINT and MULTIPOINT sf objects
#'
#'
#' @export
add_column <- function(
	map,
	data = get_map_data(map),
	polyline = NULL,
	lon = NULL,
	lat = NULL,
	fill_colour = NULL,
	fill_opacity = NULL,
	stroke_colour = NULL,
	stroke_opacity = NULL,
	stroke_width = NULL,
	radius = 1000,
	elevation = NULL,
	elevation_scale = 1,
	coverage = 1,
	angle = 0,
	disk_resolution = 20,
	tooltip = NULL,
	auto_highlight = FALSE,
	highlight_colour = "#AAFFFFFF",
	layer_id = NULL,
	id = NULL,
	palette = "viridis",
	na_colour = "#808080FF",
	legend = FALSE,
	legend_options = NULL,
	legend_format = NULL,
	update_view = TRUE,
	focus_layer = FALSE,
	digits = 6,
	transitions = NULL,
	brush_radius = NULL,
	...
) {

	if( nrow( data ) == 0 ) {
		return( clear_column( map, layer_id, ... ) )
	}
	## using binary data requires hex-colorus to include teh alpha
	if( !is.null( fill_colour ) ) {
		fill_colour <- appendAlpha( fill_colour )
	}
	if( !is.null( stroke_colour ) ) {
		stroke_colour <- appendAlpha( stroke_colour )
	}

	l <- list()
	l[["polyline"]] <- force( polyline )
	l[["lon"]] <- force( lon )
	l[["lat"]] <- force( lat )
	l[["fill_colour"]] <- fill_colour
	l[["fill_opacity"]] <- resolve_opacity( fill_opacity )
	l[["stroke_colour"]] <-force( stroke_colour )
	l[["stroke_width"]] <- force( stroke_width )
	l[["stroke_opacity"]] <- resolve_opacity( stroke_opacity )
	l[["elevation"]] <- force( elevation )
	l[["tooltip"]] <- force( tooltip )
	l[["id"]] <- force( id )
	l[["na_colour"]] <- force( na_colour )


	l <- resolve_palette( l, palette )
	l <- resolve_legend( l, legend )
	l <- resolve_legend_options( l, legend_options )
	l <- resolve_elevation_data( data, l, elevation, c("POINT") )

	bbox <- init_bbox()
	update_view <- force( update_view )
	focus_layer <- force( focus_layer )

	is_extruded <- FALSE
	## issue 287 & 296
	if( !is.null( elevation ) ) {
		is_extruded <- TRUE
	}
	if( !is.null( l[["stroke_width"]] ) | !is.null( l[["stroke_colour"]] ) ) {
		is_extruded <- FALSE
		if( !is.null( elevation ) ) {
			message("stroke provided, ignoring elevation")
		}
		if( is.null( l[["stroke_width"]] ) ) {
			l[["stroke_width"]] <- 1L
		}
	}

	if ( !is.null(l[["data"]]) ) {
		data <- l[["data"]]
		l[["data"]] <- NULL
	}

	if( !is.null(l[["bbox"]] ) ) {
		bbox <- l[["bbox"]]
		l[["bbox"]] <- NULL
	}

	checkHexAlpha(highlight_colour)

	layer_id <- layerId(layer_id, "column")
	map <- addDependency(map, mapdeckColumnDependency())

	tp <- l[["data_type"]]
	l[["data_type"]] <- NULL
	jsfunc <- "add_column_geo_columnar"


	if ( tp == "sf" ) {

		geometry_column <- list( geometry = c("lon","lat") )  ## using columnar structure, the 'sf' is converted to a data.frame
		## so the geometry columns are obtained after sfheaders::sf_to_df()
		l[["geometry"]] <- NULL
		shape <- rcpp_point_sf_columnar( data, l, geometry_column, digits, "column" )

		# geometry_column <- c( "geometry" )
		# shape <- rcpp_point_geojson( data, l, geometry_column, digits, "column" )

	} else if ( tp == "df" ) {

		geometry_column <- list( geometry = c("lon", "lat") )
		shape <- rcpp_point_df_columnar( data, l, geometry_column, digits, "column" )

		# geometry_column <- list( geometry = c("lon", "lat") )
		# shape <- rcpp_point_geojson_df( data, l, geometry_column, digits, "column" )

	} else if ( tp == "sfencoded" ) {
		geometry_column <- "polyline"
		shape <- rcpp_point_polyline( data, l, geometry_column, "column" )
		jsfunc <- "add_column_polyline"

	}

	js_transitions <- resolve_transitions( transitions, "column" )

	if( inherits( legend, "json" ) ) {
		shape[["legend"]] <- legend
		legend_format <- "hex"
	} else {
		shape[["legend"]] <- resolve_legend_format( shape[["legend"]], legend_format )
		legend_format <- "rgb"
	}

	invoke_method(
		map, jsfunc, map_type( map ), shape[["data"]], nrow(data), layer_id, auto_highlight, highlight_colour,
		radius, elevation_scale, disk_resolution, angle, coverage, shape[["legend"]], legend_format,
		bbox, update_view, focus_layer, js_transitions, is_extruded, brush_radius
	)
}


#' @rdname clear
#' @export
clear_column <- function( map, layer_id = NULL, update_view = TRUE, clear_legend = TRUE) {
	layer_id <- layerId(layer_id, "column")
	invoke_method(map, "md_layer_clear", map_type( map ), layer_id, "column", update_view, clear_legend )
}