在以圆形锯齿形的方式定位标签时，是否有功能可以使圆形图清晰可见？

Question

I am trying to create a circular barplot for 300 data points. The output of my codes is in accordance with my requirement but there is a problem of labels visibility. I want some modifications to improve the visibility of labels. For example, plotting labels in a zig-zag way could be a solution. How can I create such type of pattern for labels in the circular bar plot? The code, as well as output, is attached.

    # library
library(tidyverse)
library(ggplot2)
library(dplyr)

# Create dataset
data <- data.frame(
        individual=paste( "Mister ", seq(1,300), sep=""),
        group=c( rep('A', 50), rep('B', 100), rep('C', 100), rep('D', 50)) ,
        value=sample( seq(10,100), 300, replace=T)
)

data = data %>% arrange(group, value)
# Set a number of 'empty bar' to add at the end of each group
empty_bar <- 3
to_add <- data.frame( matrix(NA, empty_bar*nlevels(data$group), ncol(data)) )
colnames(to_add) <- colnames(data)
to_add$group <- rep(levels(data$group), each=empty_bar)
data <- rbind(data, to_add)
data <- data %>% arrange(group)
data$id <- seq(1, nrow(data))

# Get the name and the y position of each label
label_data <- data
number_of_bar <- nrow(label_data)
angle <- 90 - 360 * (label_data$id-0.5) /number_of_bar     # I substract 0.5 because the letter must have the angle of the center of the bars. Not extreme right(1) or extreme left (0)
label_data$hjust <- ifelse( angle < -90, 1, 0)
label_data$angle <- ifelse(angle < -90, angle+180, angle)

# prepare a data frame for base lines
base_data <- data %>% 
        group_by(group) %>% 
        summarize(start=min(id), end=max(id) - empty_bar) %>% 
        rowwise() %>% 
        mutate(title=mean(c(start, end)))

# prepare a data frame for grid (scales)
grid_data <- base_data
grid_data$end <- grid_data$end[ c( nrow(grid_data), 1:nrow(grid_data)-1)] + 1
grid_data$start <- grid_data$start - 1
grid_data <- grid_data[-1,]

# Make the plot
p <- ggplot(data, aes(x=as.factor(id), y=value, fill=group)) +       # Note that id is a factor. If x is numeric, there is some space between the first bar

        geom_bar(aes(x=as.factor(id), y=value, fill=group), stat="identity", alpha=0.5) +

        # Add a val=100/75/50/25 lines. I do it at the beginning to make sur barplots are OVER it.
        geom_segment(data=grid_data, aes(x = end, y = 80, xend = start, yend = 80), colour = "grey", alpha=1, size=0.3 , inherit.aes = FALSE ) +
        geom_segment(data=grid_data, aes(x = end, y = 60, xend = start, yend = 60), colour = "grey", alpha=1, size=0.3 , inherit.aes = FALSE ) +
        geom_segment(data=grid_data, aes(x = end, y = 40, xend = start, yend = 40), colour = "grey", alpha=1, size=0.3 , inherit.aes = FALSE ) +
        geom_segment(data=grid_data, aes(x = end, y = 20, xend = start, yend = 20), colour = "grey", alpha=1, size=0.3 , inherit.aes = FALSE ) +

        # Add text showing the value of each 100/75/50/25 lines
        annotate("text", x = rep(max(data$id),4), y = c(20, 40, 60, 80), label = c("20", "40", "60", "80") , color="grey", size=3 , angle=0, fontface="bold", hjust=1) +

        geom_bar(aes(x=as.factor(id), y=value, fill=group), stat="identity", alpha=0.5) +
        ylim(-50,120) +
        theme_minimal() +
        theme(
                legend.position = "none",
                axis.text = element_blank(),
                axis.title = element_blank(),
                panel.grid = element_blank(),
                plot.margin = unit(rep(-1,4), "cm") 
        ) +
        coord_polar() + 
        geom_text(data=label_data, aes(x=id, y=value+10, label=individual, hjust=hjust), color="black", fontface="bold",alpha=0.6, size=2.5, angle= label_data$angle, inherit.aes = FALSE )
p

Answer 1

I inserted a small section to fix the half of the graph. The idea would be the same for the other half.

# Keep your code as it is: 
.....
data <- rbind(data, to_add)
data <- data %>% arrange(group)
data$id <- seq(1, nrow(data))

I added but replace was used incorrectly, please see my corrected answer above.

data<-data %>% 
  mutate(
    is = id == 2*round(id/2, 0), 
    individual = replace(paste("                     ", individual, sep=""), is==TRUE, 
      paste(individual, " ", sep = "")) 
)
# end here 

# Get the name and the y position of each label
# 
p

Answer 2

I was incorrectly used replace in my previous answer. I used ifelse and the graph looks better.

After your code

data$id <- seq(1, nrow(data))

insert:

data <- data %>% 
  mutate(
    is = id%%2, 
    individual =  ifelse(is==1, 
        paste("                         ", individual, sep=""), 
        paste(individual, "                     ", sep = "")))

Since "Mister" appeared in every point, I wonder if it is better to replace it with "M", or even just leave it blank.