ggplot2多层绘图上色与图层管理问题求助

以下是针对你遇到的四个问题的具体解决方案：

问题1：无法识别数据框存储的颜色 #

你把fill放在aes()里，导致ggplot将颜色值当作分类变量映射，而非直接使用颜色本身。只需把fill移出aes()，作为geom_rect的直接参数即可：

# 垂直色块图层修正
geom_rect(
  data = vparam.df,
  aes(xmin = xmin, xmax = xmax, ymin = ymin, ymax = ymax),
  inherit.aes = FALSE,
  fill = vparam.df$fill  # 直接指定数据框中的颜色列
)

水平色块图层同理，将fill从aes()中移出，改为直接引用hparam.df$fill。

问题2：ggpattern全局应用相同图案 #

使用ggpattern的geom_rect_pattern，通过aes()映射pattern变量，再用scale_pattern_manual指定对应图案，实现分区域设置不同图案：

1. 先给hparam.df添加图案类型列：

hparam.df = data.frame(
  xmin = 0,
  xmax = 35,
  ymin = c(5, 10),
  ymax = c(10, 15),
  xlabel = rep(-1, 2),
  ylabel = c(7.5, 12.5),
  fill = c("#52be80", "#c0392b"),
  pattern = c("dot", "stripe"),  # 添加图案类型标识
  label = c("medium","strong")
)

2. 替换原水平geom_rect为：

geom_rect_pattern(
  data = hparam.df,
  aes(xmin = xmin, xmax = xmax, ymin = ymin, ymax = ymax, pattern = pattern),
  inherit.aes = FALSE,
  fill = hparam.df$fill,
  alpha = 0.2,
  pattern_fill = "black",
  pattern_density = 0.1,
  pattern_spacing = 0.02
) +
scale_pattern_manual(values = c(dot = "circle", stripe = "stripe"))  # 映射图案类型

问题3：十六进制透明度设置异常 #

不要用十六进制末尾加00的方式控制透明度，直接使用alpha参数即可，配合问题1的修改（fill移出aes()），就能正常生效。

问题4：geom_point无法识别wtype字段 #

你需要在geom_point的aes()里明确映射wtype字段，比如按类型设置点的颜色或形状：

geom_point(aes(color = wtype), size=1)

如果不需要区分样式，只是确保字段被识别，也可以显式声明映射，但通常用于视觉属性区分。

完整修正后的代码 #

library(ggplot2)
library(ggpattern)

vparam.df = data.frame(
  ymin = 0,
  ymax = 15,
  xmin = c(0, 7, 14, 21, 28),
  xmax = c(7, 14, 21, 28, 35),
  xlabel = c(3.5, 10.5, 17.5, 24.5, 31.5),
  ylabel = rep(-1,5),
  fill = c("#1e8449", "#52be80", "#f4d03f", "#f39c12","#c0392b"),
  label = c("low","mod. low","medium","pretty strong","strong")
)

hparam.df = data.frame(
  xmin = 0,
  xmax = 35,
  ymin = c(5, 10),
  ymax = c(10, 15),
  xlabel = rep(-1, 2),
  ylabel = c(7.5, 12.5),
  fill = c("#52be80", "#c0392b"),
  pattern = c("dot", "stripe"),
  label = c("medium","strong")
)

df = structure(list(xvar = c(13, 20, 16, 11, 21, 13, 13, 7, 9, 16, 
11, 13, 15, 13, 22, 16), yvar = c(0, 2, 2, 4, 2, 4, 7, 5, 5, 
0, 7, 2, 2, 7, 2, 7), wtype = c("Type4", "Type3", 
"Type4", "Type4", "Type1", "Type1", 
"Type4", "Type1", "Type1", "Type1", 
"Type3", "Type1", "Type2", "Type4", 
"Type2", "Type1")), row.names = c(NA, -16L), class = c("tbl_df", 
"tbl", "data.frame"))

ggplot(df, aes(x=xvar, y=yvar )) +
  # 垂直色块层
  geom_rect(
    data = vparam.df,
    aes(xmin = xmin, xmax = xmax, ymin = ymin, ymax = ymax),
    inherit.aes = FALSE,
    fill = vparam.df$fill
  ) +
  # 水平图案层
  geom_rect_pattern(
    data = hparam.df,
    aes(xmin = xmin, xmax = xmax, ymin = ymin, ymax = ymax, pattern = pattern),
    inherit.aes = FALSE,
    fill = hparam.df$fill,
    alpha = 0.2,
    pattern_fill = "black",
    pattern_density = 0.1,
    pattern_spacing = 0.02
  ) +
  scale_pattern_manual(values = c(dot = "circle", stripe = "stripe")) +
  # 数据点层，映射wtype
  geom_point(aes(color = wtype), size=1) +
  # 文本标签层
  geom_text(data=vparam.df, aes(x=xlabel, y=ylabel, label=label), size=2) +
  geom_text(data=hparam.df, aes(x=xlabel, y=ylabel, label=label), size=2, angle=90) +
  # 修正坐标轴类型（原离散刻度不适合连续数值）
  scale_y_continuous(breaks = seq(0,15,5)) +
  scale_x_continuous(breaks = seq(0,35,7)) +
  # 主题设置
  theme(legend.position = "none")

内容的提问来源于stack exchange，提问作者Nico