In geom_pointrange, changes to the fatten arg are not reflected in the legend

[davidhodge931]

library(ggplot2)

df <- data.frame(
  trt = factor(c(1, 1, 2, 2)),
  resp = c(1, 5, 3, 4),
  group = factor(c(1, 2, 1, 2)),
  upper = c(1.1, 5.3, 3.3, 4.2),
  lower = c(0.8, 4.6, 2.4, 3.6)
)

df %>% 
  ggplot() +
  geom_pointrange(aes(x = trt, y = resp, col = group, ymin = lower, ymax = upper),
                  fatten = 1)

[smouksassi]

possibly related to #2798
fatten is not a parameter and currently, the legend does not reflect any changes to it and is currently kind of hard coded:

ggplot2/R/legend-draw.r

Line 197 in 0e64d9c

draw_key_point(transform(data, size = (data$size %||% 1.5) * 4), params)

with the ongoing work of linewidth aesthetic things might be easier to handle/fix.
#3672

[yutannihilation]

Thanks @smouksassi. As suggested, I think this issue is resolved by #3672. Now you can combine size and linewidth to control the sizes of points and lines differently. My understanding is fatten was a workaround for this, but is probably no longer needed.

library(ggplot2)

df <- data.frame(
  trt = factor(c(1, 1, 2, 2)),
  resp = c(1, 5, 3, 4),
  group = factor(c(1, 2, 1, 2)),
  upper = c(1.1, 5.3, 3.3, 4.2),
  lower = c(0.8, 4.6, 2.4, 3.6)
)

ggplot(df) +
  geom_pointrange(aes(x = trt, y = resp, col = group, ymin = lower, ymax = upper),
    size = 2, linewidth = 0.5
  ) +
  theme(legend.key.size = unit(0.15, "npc"))

^{Created on 2022-06-19 by the reprex package (v2.0.1)}