2025-01-21 ggplot2文字加背景，群加边框

1. 全部群架边框

library(ggplot2)
library(shadowtext)
library(ggrepel)
library(ggunchull)

head(iris)

# 计算每个species的边框
# setup a proper distance to extend (and simplify) the circle (here use 3% of the range of x axis)
delta_r <- 0.03
th_r <- 0.03
delta <- diff(range(iris$Sepal.Length)) * delta_r # 3% of the range of x axis
th <- diff(range(iris$Sepal.Width)) * th_r # 3% of the range of y axis

# 计算每个物种类型的中位数
species_type_med <- iris |>
  dplyr::group_by(Species) |>
  dplyr::summarise(
    length_median = median(Sepal.Length), # x轴中位数
    width_median = median(Sepal.Width) # y轴中位数
  )

species_type_med

# 为数据添加微小的随机扰动
iris_jittered <- iris
set.seed(123) # 设置随机种子以确保结果可重现
iris_jittered$Sepal.Length <- iris_jittered$Sepal.Length + rnorm(nrow(iris_jittered), 0, 0.001)
iris_jittered$Sepal.Width <- iris_jittered$Sepal.Width + rnorm(nrow(iris_jittered), 0, 0.001)

# 使用添加扰动后的数据绘图
ggplot(iris_jittered, aes(x = Sepal.Length, y = Sepal.Width, fill = Species)) +
  geom_point(size = 3, shape = 21, color = "black") +
  stat_unchull(
    aes(color = Species, fill = Species), # 按Species着色和填充
    alpha = 0.3,    # 设置透明度为 0.3
    delta = delta,  # 使用计算的 x 轴扩展距离
    th = th,        # 使用计算的 y 轴扩展距离
    n = 5           # 设置平滑度（控制边界的圆滑程度）
) +
  geom_shadowtext(
    aes(x = length_median, y = width_median, label = Species),
    fontface = "bold",
    color = "black",
    bg.colour='white',
    data = species_type_med,
    point.padding = unit(0.5, "lines")
  ) +
  theme_classic() +
  theme(
    axis.line = element_blank(),
    axis.text = element_blank(),
    axis.ticks = element_blank(),
    axis.title = element_blank()
  ) 

image.png

2. 指定群架边框

# 特定群加边框
# 使用添加扰动后的数据绘图
ggplot(iris_jittered, aes(x = Sepal.Length, y = Sepal.Width, fill = Species)) +
  geom_point(size = 3, shape = 21, color = "black") +
  stat_unchull(data = subset(iris_jittered, Species == "setosa"),
    aes(color = Species, fill = Species), # 按Species着色和填充
    alpha = 0.3,    # 设置透明度为 0.3
    delta = delta,  # 使用计算的 x 轴扩展距离
    th = th,        # 使用计算的 y 轴扩展距离
    n = 5           # 设置平滑度（控制边界的圆滑程度）
) +
  geom_shadowtext(
    aes(x = length_median, y = width_median, label = Species),
    fontface = "bold",
    color = "black",
    bg.colour='white',
    data = species_type_med,
    point.padding = unit(0.5, "lines")
  ) +
  theme_classic() +
  theme(
    axis.line = element_blank(),
    axis.text = element_blank(),
    axis.ticks = element_blank(),
    axis.title = element_blank()
  )

image.png