R/stat_sphere_shading.R

In Clement-Viguier/ShadeR: Create shader function for ggplot.

#' Compute sphere shading per group for the given data
#'
#' The sphere shading statistic transform the height data into sphere shading data value.
#' See ?ray_shade from the rayshader package.
#'
#' @import ggplot2 rayshader reshape2
#' @inheritParams layer
#' @inheritParams geom_fleck
#' @export
#' @examples
#' # Example with the volcano dataset
#'
#'
stat_sphere_shading <- function(mapping = NULL, data = NULL,
                             geom = "point", position = "identity",
                             sun.angle = 1/3*pi,
                             slope= F,
                             res = 1,
                             zscale = 1,
                             ...,
                             show.legend = NA,
                             inherit.aes = TRUE) {
  ggplot2::layer(
    data = data,
    mapping = mapping,
    stat = StatRayShading,
    geom = geom,
    position = position,
    show.legend = show.legend,
    inherit.aes = inherit.aes,
    params = list(
      res = res,
      zscale = 1,
      slope = slope,
      na.rm = FALSE,
      sun.angle = sun.angle,
      ...
    )
  )
}

#' @rdname ggplot2-ggproto
#' @format NULL
#' @usage NULL
#' @export
StatSphereShading <- ggproto("StatSphereShading", Stat,
                          compute_group = function(data, scales, sun.angle = pi/3, slope = F, params,  res = 1, zscale = 1) {

                            # deg <- ((pi/2 - sun.angle) * (180/pi)) %% 360
                            deg <- ((sun.angle) * (180/pi)) %% 360

                            # browser()

                            # print(summary(data))
                            height <- dcast(data,x~y, value.var = "z")
                            # print(dim(height))
                            # shade <- rotate(sphere_shade(as.matrix(height[,-1]), sunangle = deg, texture = "bw", zscale = zscale, remove_edges = F)[, ,1])

                            shade2 <- antirotate(sphere_shade(flipv(as.matrix(height[,-1])), sunangle = deg, texture = "bw", zscale = zscale, remove_edges = F)[, ,1])
                            rownames(shade2) <- height[,1]
                            colnames(shade2) <- colnames(height)[-1]
                            data2 <- melt((shade2))

                            # print(summary(melt(shade)))
                            # data <- melt(shade)
                            # print(summary(data))

                            # x <- rep(1:dim(shade)[1], dim(shade)[2])
                            # shade <- cbind(x, data)

                            colnames(data2) <- c("x", "y", "z")
                            #data$y <- - as.numeric(data$y)
                            # data2$y <- sign(data$y) * data2$y



                            return(cbind(data2, data[,setdiff(colnames(data), colnames(data2))]))
                          },
                          required_aes = c("x", "y", "z")
)

rotate <- function(x) t(apply(x, 2, rev))
antirotate <- function(x) apply(t(x),2,rev)
flipv <- function(x) apply(x,2,rev)