Animating ggforce::geom_circle() using gganimate gives bad animation.

[steenharsted]

Hi,
Thank you for your great packages gganimate and ggforce.

I am having difficulties animating ggforce::geom_circle(). The geom_circle() objects are not properly animated. The animation seems to only include the raw data points.

The animation of the standard geom_path() works as intended.

code:

library(tidyverse)
library(gganimate)
library(ggforce)

person <- tribble(
  ~object,    ~x,    ~y,   ~group, ~size,
  "head",      100,   180,      1,    10, 
  "neck",      100,   160,      1,    3, 
  "pelvis",    100,   100,      1,    3, 
  "lhip",       90,    90,      2,    3, 
  "rhip",      110,    90,      3,    3,
  "lknee",      80,    45,      2,    3,
  "rknee",     120,    45,      3,    3, 
  "lfoot",      50,     0,      2,    3, 
  "rfoot",      150,    0,      3,    3,
  "lshoulder",   85,  155,      4,    3, 
  "rshoulder",  115,  155,      5,    3, 
  "lhand",      75,   100,      4,    3, 
  "rhand",      125,  100,      5,    3)


frame <-  c(1, 10, 20, 30, 40, 50, 60, 70, 80, 90)

data_for_plot <- 
  crossing(
    frame,
    person) %>%
  mutate(
    x = x + frame,
    y = y + sin(frame)*5)
 
plot_data <- ggplot(data_for_plot, aes(x0=x, y0=y, r=size/2, group=group, fill=factor(group), color=factor(group))) +
  geom_circle() +
  geom_path(aes(x,y)) +
  coord_equal() + 
  labs(x="cm", y="cm") + 
  theme_classic() +
  theme(legend.position = "none")

plot_data+
  transition_states(frame)