Match point and line transitions

uk-driver-deaths.R

library(tidyverse)
library(lubridate)
library(gganimate)
library(ggfortify)

deaths <- fortify(UKDriverDeaths) %>% 
  rename(date = Index, deaths = Data) %>% 
  mutate(year = year(date), month = month(date))

p <- ggplot(deaths, aes(month, deaths)) +
  geom_point() +
  geom_line() +
  scale_y_continuous(labels = scales::number) +
  scale_x_continuous(breaks = 1:12, labels = month.abb) +
  theme(axis.title = element_blank()) +
  theme(panel.grid.minor = element_blank()) +
  transition_states(year, 1, 2, wrap = FALSE) +
  theme(title = element_text(size = 14)) +
  labs(title = "UK driver deaths in {closest_state}")

animate(p, fps = 24, duration = 12)
anim_save("uk-driver-deaths.gif")

library(tweenr)

deaths_s <- split(deaths, deaths$year)

f <- function(x, y) {
  fps <- 24
  dur <- 12
  
  ns <- length(deaths_s)
  tt <- 1
  st <- 2
  
  dur_s <- dur / ns
  tf <- round(fps * dur_s * (tt / (tt + st)), 0)
  sf <- round(fps * dur_s * (st / (tt + st)), 0)
    
  keep_state(tween_state(x, y, 'cubic-in-out', tf), sf)
}

deaths_f <- reduce(deaths_s, f)

p2 <- ggplot(deaths_f, aes(month, deaths)) +
  geom_point() +
  geom_line() +
  scale_y_continuous(labels = scales::number) +
  scale_x_continuous(breaks = 1:12, labels = month.abb) +
  theme(axis.title = element_blank()) +
  theme(panel.grid.minor = element_blank()) +
  transition_manual(.frame) +
  theme(title = element_text(size = 14)) +
  labs(title = "UK driver deaths in {current_frame}")

animate(p2, fps = 24, duration = 12)
anim_save("uk-driver-deaths_manual.gif")