gistfile1.txt

library(tidyverse)
library(ggforce)

bl_gradient <- grid::linearGradient(colours = rev(c("gray40", "#9B9B9B")),
                                    stops = c(0.12, 0.4, 0.6))

br_gradient <- grid::linearGradient(colours = rev(c("grey10",  "#484848")),
                                    x1 = unit(0, "npc"), y1 = unit(0, "npc"), 
                                    x2 = unit(1, "npc"), y2 = unit(1, "npc"),
                                    stops = c(0, 0.5, 0.8))

bb_gradient <- grid::linearGradient(colours = rev(c("grey30",  "#D7D7D7")),
                                    x1 = unit(0.5, "npc"), y1 = unit(0, "npc"), 
                                    x2 = unit(0.5, "npc"), y2 = unit(1, "npc"),
                                    stops = c(0.2, 0.5)
                                    )

cube <- tribble(
  ~face, ~x, ~y, ~fill,
  "bl", c(-2, -2, 0, 0), c(-1.15, 1.15, 2.3, -2.3), bl_gradient,
  "br", c(0, 2, 2, 0), c(2.3, 1.15, -1.15, -2.3), br_gradient,
  "bb", c(-2, 0, 2, 0), c(-1.15, -2.3, -1.15, 0), bb_gradient,
  "ft", c(-2, 2, 0), c(1.15, 1.15, 0), "white",
  "fr", c(0, 2, 0), c(0, 1.15, -2.3), "#E3E3E3"
  ) %>% 
  unnest_longer(c(x, y)) %>% 
  mutate(
    face = fct_inorder(face),
    x = x * 0.9,
    y = y * 0.9
  ) 

ggplot() +
  geom_ellipse(aes(x0 = 0, y0 = 0, a = 3, b = 3, m1 = 4.5, angle = 0), fill = "black") +
  geom_polygon(data = cube, aes(x, y, group = face, fill = fill)) +
  scale_fill_identity() +
  coord_fixed() +
  theme_void() +
  theme(
    plot.background = element_rect(fill = "grey99", color = NA)
  )