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rggplot2textdonut-chart

Multi-layer donut chart with geom_textpath(): how to remove black connector line?

I wish to plot a nested, 2-layer donut chart with curved text using geomtextpath::geom_textpath() following the code provided by Allan Cameron in this post. Unfortunately, the text is obscured by a black connector line that makes the plot unreadible and I cannot figure out how to remove it.

enter image description here

Here is some data for a reproducible example:

g3 <- structure(list(top_level = c("1-ha plot", "Relevé", "Transect", 
                               "1-ha plot", "1-ha plot", "1-ha plot", "Relevé","Relevé","Transect", "Transect", "Transect", "Transect", "Transect", "Transect"), width = c(240L, 240L, 858L, 189L, 30L, 21L, 132L, 108L, 48L, 
          9L, 644L, 47L, 32L, 78L), name = c("level1", "level1", "level1","level2", "level2", "level2","level2", "level2", "level2", "level2","level2", "level2", "level2", "level2"), value = c("1-ha plot","Relevé", "Transect", "Cameroon", "DRC", "Gabon", "Cameroon","Gabon", "Cameroon", "Equatorial Guinea", "Gabon", "Guinea","Liberia", "São Tomé and Príncipe"), ymid = c(1, 1, 1, 2,2, 2, 2, 2, 2, 2, 2, 2, 2, 2), ymax = c(1.5, 1.5, 1.5, 2.5, 2.5,2.5, 2.5, 2.5, 2.5, 2.5, 2.5, 2.5, 2.5, 2.5), ymin = c(0.5, 0.5,0.5, 1.5, 1.5, 1.5, 1.5, 1.5, 1.5, 1.5, 1.5, 1.5, 1.5, 1.5), xmin = c(0, 240, 480, 0, 189, 219, 240, 372, 480, 528, 537,1181, 1228, 1260), xmax = c(240L, 480L, 1338L, 189L, 219L,240L, 372L, 480L, 528L, 537L, 1181L, 1228L, 1260L, 1338L),xmid = c(120, 360, 909, 94.5, 204, 229.5, 306, 426, 504,532.5, 859, 1204.5, 1244, 1299)), class = c("grouped_df","tbl_df", "tbl", "data.frame"), row.names = c(NA, -14L), groups = g3 <- structure(list(name = c("level1", "level2"), .rows = structure(list(1:3,4:14), ptype = integer(0), class = c("vctrs_list_of","vctrs_vctr", "list"))), class = c("tbl_df", "tbl", "data.frame"), row.names = c(NA, -2L), .drop = TRUE))

I plot the donut chart using ggplot and geomtextpath

library(ggplot2)
library(geomtextpath)

g3 %>% ggplot(aes(xmid, ymid, fill = top_level)) +
geom_rect(aes(xmin = xmin, xmax = xmax, ymin = ymin, ymax = ymax,
            alpha = name, color = top_level)) +
scale_alpha_manual(values = c(1, 0.2)) +
geomtextpath::geom_textpath(aes(y = ymid + 0.25, label = value, group = value)) +
scale_alpha_manual(values = c(1, 0.2)) +
scale_fill_manual(values = c("#4bdca4", "#bf65e6", "#eb2b42")) +
scale_colour_manual(values = c("#4bdca4", "#bf65e6", "#eb2b42")) +
scale_y_continuous(limits = c(-0.5, 3.6)) +
coord_polar() +
theme_void() +
theme(legend.position = "none")

I suspect this line is somewhat due to the aes(group = ) argument.

Solution

  • Simply set text_only=TRUE in geomtextpath::geom_textpath to show only the label:

    library(ggplot2)
library(geomtextpath)

g3 |> ggplot(aes(xmid, ymid, fill = top_level)) +
  geom_rect(aes(
    xmin = xmin, xmax = xmax, ymin = ymin, ymax = ymax,
    alpha = name, color = top_level
  )) +
  scale_alpha_manual(values = c(1, 0.2)) +
  geomtextpath::geom_textpath(
    aes(y = ymid + 0.25, label = value, group = value),
    text_only = TRUE
  ) +
  scale_alpha_manual(values = c(1, 0.2)) +
  scale_fill_manual(
    values = c("#4bdca4", "#bf65e6", "#eb2b42"),
    aesthetics = c("color", "fill")
  ) +
  scale_y_continuous(limits = c(-0.5, 3.6)) +
  coord_polar() +
  theme_void() +
  theme(legend.position = "none")