#' @rdname tm_raster
#' @name opt_tm_raster
#' @param interpolate Should the raster image be interpolated? Currently only applicable in view mode (passed on to [`grid`][grid::rasterGrob()])
#' @export
opt_tm_raster = function(interpolate = TRUE) {
list(trans.args = list(),
mapping.args = list(interpolate = interpolate))
}
#' Map layer: raster
#'
#' Map layer that draws rasters. Supported visual variable is: `col` (the color).
#'
#' The visual variable arguments (e.g. `col`) can be specified with either a data
#' variable name (e.g., a spatial vector attribute or a raster layer of the object
#' specified in [tm_shape()]), or with a visual value (for `col`, a color is expected).
#' Multiple values can be specified: in that case facets are created.
#' These facets can be combined with other faceting data variables, specified with [tm_facets()].
#'
#' * The `*.scale` arguments determine the used scale to map the data values to
#' visual variable values. These can be specified with one of the available
#' `tm_scale_*()` functions. The default is specified by the tmap option ([tm_options()]) `scales.var`.
#'
#' * The `*.legend` arguments determine the used legend, specified with [tm_legend()].
#' The default legend and its settings are determined by the tmap options ([tm_options()]) `legend.` .
#'
#' * The `*.chart` arguments specify additional charts, specified with `tm_chart_`, e.g. [tm_chart_histogram()]
#'
#' * The `*.free` arguments determine whether scales are applied freely across facets, or shared.
#' A logical value is required. They can also be specified with a vector of three
#' logical values; these determine whether scales are applied freely per facet dimension.
#' This is only useful when facets are applied (see [tm_facets()]).
#' There are maximally three facet dimensions: rows, columns, and pages. This only
#' applies for a facet grid ([tm_facets_grid()]). For instance, `col.free = c(TRUE, FALSE, FALSE)`
#' means that for the visual variable `col`, each row of facets will have its own
#' scale, and therefore its own legend. For facet wraps and stacks
#' ([tm_facets_wrap()] and [tm_facets_stack()]) there is only one facet dimension,
#' so the `*.free` argument requires only one logical value.
#'
#' @param col,col.scale,col.legend,col.chart,col.free Visual variable that determines the color.
#' See details.
#' @param col_alpha,col_alpha.scale,col_alpha.legend,col_alpha.chart,col_alpha.free Visual variable
#' that determines the alpha transparency. See details.
#' @param zindex Map layers are drawn on top of each other.
#' The `zindex` numbers (one for each map layer) determines the stacking order.
#' By default the map layers are drawn in the order they are called.
#' @param group Name of the group to which this layer belongs. This is only
#' relevant in view mode, where layer groups can be switched (see `group.control`)
#' @param group.control In view mode, the group control determines how layer groups
#' can be switched on and off. Options: `"radio"` for radio buttons (meaning only
#' one group can be shown), `"check"` for check boxes (so multiple groups can be
#' shown), and `"none"` for no control (the group cannot be (de)selected).
#' @param options options passed on to the corresponding `opt_<layer_function>` function
#' @param ... to catch deprecated arguments from version < 4.0
#' @example ./examples/tm_raster.R
#' @export
tm_raster = function(col = tm_shape_vars(),
col.scale = tm_scale(value.na = "#00000000"),
col.legend = tm_legend(),
col.chart = tm_chart_none(),
col.free = NA,
col_alpha = tm_const(),
col_alpha.scale = tm_scale(),
col_alpha.legend = tm_legend(),
col_alpha.chart = tm_chart_none(),
col_alpha.free = NA,
zindex = NA,
group = NA,
group.control = "check",
options = opt_tm_raster(),
...) {
args = list(...)
args_called = as.list(match.call()[-1]) #lapply(as.list(match.call()[-1]), eval, envir = parent.frame())
if (any(v3_only("tm_raster") %in% names(args))) {
layer_fun = if ("called_from" %in% names(args)) {
args$called_from
} else {
"tm_raster"
}
v3_start_message()
if (!("style" %in% names(args))) {
if (!"breaks" %in% names(args)) {
style = "pretty"
} else {
style = "fixed"
}
} else {
style = args$style
}
v3_list_init()
if (length(style) > 1) {
style = style[1]
.TMAP$v3_list$mult = TRUE
}
# v3 visual variable: col
col.scale.args = list(n = v3_impute(args, "n", 5),
style = style,
style.args = v3_impute(args, "style.args", list()),
breaks = v3_impute(args, "breaks", NULL),
interval.closure = v3_impute(args, "interval.closure", "left"),
drop.levels = v3_impute(args, "drop.levels", FALSE),
midpoint = v3_impute(args, "midpoint", NULL),
as.count = v3_impute(args, "as.count", NA),
values = v3_impute(args, "palette", NA, "values"),
values.repeat = !v3_impute(args, "stretch.palette", TRUE, "values.repeat"),
values.range = v3_impute(args, "contrast", NA, "values.range"),
values.scale = 1,
value.na = v3_impute(args, "colorNA", NA, "value.na"),
value.null = v3_impute(args, "colorNULL", NA, "value.null"),
value.neutral = NA,
labels = v3_impute(args, "labels", NULL),
label.na = v3_impute(args, "textNA", NA, "label.na"),
label.null = NA,
label.format = v3_impute(args, "legend.format", list(), "label.format"))
col.scale.args$fun_pref = if (style == "cat") {
"categorical"
} else if (style %in% c("fixed", "sd", "equal", "pretty", "quantile",
"kmeans", "hclust", "bclust", "fisher", "jenks",
"dpih", "headtails", "log10_pretty")) {
"intervals"
} else if (style == "cont") {
"continuous"
} else if (style == "log10") {
"continuous_log"
} else if (style == "order") {
"rank"
} else {
stop("unknown style")
}
if ("style" %in% names(args)) {
v3_tm_scale_instead_of_style(style, scale_fun = col.scale.args$fun_pref, vv = "col", layer_fun = layer_fun, arg_list = v3_list_get())
} else {
v3_tm_scale(scale_fun = "", vv = "col", layer_fun = layer_fun, arg_list = v3_list_get())
}
col.scale = do.call("tm_scale", args = col.scale.args)
if ("alpha" %in% names(args)) {
col_alpha = args$alpha
v3_message_col_alpha(layer_fun = layer_fun, orig = "alpha")
}
v3_list_init()
if ("legend.show" %in% names(args) && !args$legend.show) {
v3_tm_legend_hide(layer_fun, arg = "legend.show", vv = "col")
lwd.legend = tm_legend_hide()
} else {
col.legend.args = alist(title = v3_impute(args, "title", NA, "title"),
na.show = v3_impute(args, "showNA", NA),
format = v3_impute(args, "legend.format", list(), "format"),
orientation = ifelse(v3_impute(args, "legend.is.portrait", TRUE, "orientation"), "portrait", "landscape"),
reverse = v3_impute(args, "legend.reverse", FALSE, "reverse"))
col.legend = do.call("tm_legend", col.legend.args)
v3_tm_legend(fun = layer_fun, vv = "col", arg_list = v3_list_get())
}
if ("legend.hist" %in% names(args) && args$legend.hist) {
col.chart = tm_chart_histogram()
v3_tm_chart_hist(layer_fun = layer_fun, vv = "col", arg = "legend.hist")
# to do: histogram title
}
}
# needed for color maps without categories (then tm_scale_categorical is used without legend, unless called)
col.legend$called = "col.legend" %in% names(args_called)
tm_element_list(tm_element(
layer = "raster",
trans.fun = tmapTransRaster,
trans.aes = list(),
trans.args = options$trans.args,
trans.isglobal = FALSE,
mapping.aes = list(col = tmapScale(aes = "col",
value = col,
scale = col.scale,
legend = col.legend,
chart = col.chart,
free = col.free),
col_alpha = tmapScale(aes = "col_alpha",
value = col_alpha,
scale = col_alpha.scale,
legend = col_alpha.legend,
chart = col_alpha.chart,
free = col_alpha.free)),
gpar = tmapGpar(fill = "__col",
col = NA,
shape = NA,
size = NA,
fill_alpha = "__col_alpha",
col_alpha = NA,
pattern = "fill",
lty = NA,
lwd = NA,
linejoin = NA,
lineend = NA),
tpar = tmapTpar(),
plot.order = tm_plot_order("DATA"),
mapping.fun = "Raster",
mapping.args = options$mapping.args,
zindex = zindex,
group = group,
group.control = group.control,
popup.vars = FALSE,
popup.format = list(),
hover = "",
id = "",
subclass = c("tm_aes_layer", "tm_layer")))
}
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.