gganimate (version 1.0.9)

shadow_wake: Show preceding frames with gradual falloff

Description

This shadow is meant to draw a small wake after data by showing the latest frames up to the current. You can choose to gradually diminish the size and/or opacity of the shadow. The length of the wake is not given in absolute frames as that would make the animation susceptible to changes in the framerate. Instead it is given as a proportion of the total length of the animation.

Usage

shadow_wake(
  wake_length,
  size = TRUE,
  alpha = TRUE,
  colour = NULL,
  fill = NULL,
  falloff = "cubic-in",
  wrap = TRUE,
  exclude_layer = NULL,
  exclude_phase = c("enter", "exit")
)

Arguments

wake_length

A number between 0 and 1 giving the length of the wake, in relation to the total number of frames.

size

Numeric indicating the size the wake should end on. If NULL then size is not modified. Can also be a boolean with TRUE beeing equal 0 and FALSE beeing equal to NULL

alpha

as size but for alpha modification of the wake

colour, fill

colour or fill the wake should end on. If NULL they are not modified.

falloff

An easing function that control how size and/or alpha should change.

wrap

Should the shadow wrap around, so that the first frame will get shadows from the end of the animation.

exclude_layer

Indexes of layers that should be excluded.

exclude_phase

Element phases that should not get a shadow. Possible values are 'enter', 'exit', 'static', 'transition', and 'raw'. If NULL all phases will be included. Defaults to 'enter' and 'exit'

See Also

Other shadows: shadow_mark(), shadow_null(), shadow_trail()

Examples

anim <- ggplot(iris, aes(Petal.Length, Sepal.Length)) +
  geom_point() +
  labs(title = "{closest_state}") +
  transition_states(Species, transition_length = 4, state_length = 1)

# `shadow_wake` can be combined with e.g. `transition_states` to show
# motion of geoms as they are in transition with respect to the selected state.
anim1 <- anim +
  shadow_wake(wake_length = 0.05)

# Different qualities can be manipulated by setting a value for it that it
# should taper off to
anim2 <- anim +
  shadow_wake(0.1, size = 10, alpha = FALSE, colour = 'grey92')

# Use `detail` in the `animate()` call to increase the number of calculated
# frames and thus make the wake smoother
if (FALSE) {
animate(anim2, detail = 5)
}