R/scale_edge_width.R

In YTLogos/ggraph: An Implementation of Grammar of Graphics for Graphs and Networks

#' Edge width scales
#'
#' This set of scales defines width scales for edge geoms. Of all the new edge
#' scales defined in ggraph, this is the only one not having an equivalent in
#' ggplot2. In essence it mimicks the use of size in
#' \code{\link[ggplot2]{geom_line}} and related. As almost all edge
#' representations are lines of some sort, edge_width will be used much more
#' often than edge_size. It is not necessary to spell out that it is an edge
#' scale as the geom knows if it is drawing an edge. Just write \code{width} and
#' not \code{edge_width} in the call to geoms.
#'
#' @return A ggproto object inheriting from \code{Scale}
#'
#' @family scale_edge_*
#'
#' @name scale_edge_width
#' @rdname scale_edge_width
#'
NULL

#' @rdname scale_edge_width
#'
#' @inheritParams ggplot2::scale_size_continuous
#'
#' @importFrom scales rescale_pal
#' @export
scale_edge_width_continuous <- function(..., range = c(1, 6)) {
    continuous_scale("edge_width", "width_c", rescale_pal(range), ...)
}
#' @rdname scale_edge_width
#'
#' @export
scale_edge_width <- scale_edge_width_continuous
#' @rdname scale_edge_width
#'
#' @inheritParams ggplot2::scale_size_discrete
#'
#' @importFrom scales rescale_pal
#' @export
scale_edge_width_discrete <- function(..., range = c(2, 6)) {
    discrete_scale("edge_width", "width_d", function(n) {
        area <- seq(range[1] ^ 2, range[2] ^ 2, length.out = n)
        sqrt(area)
    }, ...)
}
#' @rdname scale_edge_width
#'
#' @inheritParams ggplot2::scale_size_manual
#'
#' @export
scale_edge_width_manual <- function(..., values) {
    manual_scale("edge_width", values, ...)
}
#' @rdname scale_edge_width
#'
#' @inheritParams ggplot2::scale_size_identity
#'
#' @importFrom scales identity_pal
#' @export
scale_edge_width_identity <- function(..., guide = "none") {
    sc <- discrete_scale("edge_width", "identity", identity_pal(), ...,
                         guide = guide, super = ScaleDiscreteIdentity)
    sc
}