R 使用ggsankey调整Sankey图中单个 node 上的标签

实现所需结果的一个选项是有条件地轻推标签，并使用例如aes()内的dplyr::case_when设置标签的对齐.为了调整标签的位置，我使用了ggplot2::stage():

library(ggplot2)
library(ggsankey)

df <- mtcars |>
  make_long(cyl, vs, am, gear, carb)

ggplot(df, aes(
  x = x, next_x = next_x,
  node = node, next_node = next_node,
  fill = factor(node), label = node
)) +
  geom_sankey(
    flow.alpha = .6,
    node.color = "gray30",
    space = 20
  ) +
  geom_sankey_label(
    aes(
      # Shift labels conditional on position
      x = stage(x,
        after_stat = x + .1 *
          dplyr::case_when(
            x == 1 ~ -1,
            x == 5 ~ 1,
            .default = 0
          )
      ),
      # Align labels conditional on position
      hjust = dplyr::case_when(
        x == "cyl" ~ 1,
        x == "carb" ~ 0,
        .default = .5
      )
    ),
    size = 3,
    color = "white",
    fill = "gray40",
    space = 20
  ) +
  scale_fill_viridis_d() +
  theme_sankey(base_size = 18) +
  theme(
    legend.position = "none",
    plot.title = element_text(hjust = .5)
  ) +
  labs(x = NULL, title = "Car features")