ggplot(mountain) +
aes(x = x) +
aes(y = y) +
coord_3d() +
aes(z = z) +
geom_surface_3d() +
scale_fill_viridis_c() +
coord_3d(ratio = c(1.5, 2, 1),
expand = FALSE,
panels = c("zmax", "xmin", "ymin"),
light = light(direction = c(1, 0, 0))) +
guides(fill = guide_colorbar_3d()) +
theme_light()