Set the easing of an animation's frames

ease_aes() chooses the easing function that shapes how the interpolation fraction moves through each transition — e.g. "cubic-in-out" starts and ends gently. By default it applies to every interpolated aesthetic; the position/color/size/alpha arguments override it for one class each, so marks can glide into place on a cubic curve while their colour crossfades evenly.

Usage

ease_aes(
  plot,
  ease = "linear",
  position = NULL,
  color = NULL,
  size = NULL,
  alpha = NULL,
  colour = NULL
)

Arguments

plot

A PlotSpec carrying a transition_states().

ease

An easing name: "linear", or a family (quad/cubic/quart/quint/sine/expo/circ/back/elastic/bounce) with a direction suffix (-in, -out, -in-out), e.g. "cubic-in-out". Used for any class not given its own easing below.

position, color, size, alpha

Optional per-class easings, named the same way as ease. NULL (the default) means "use ease". Each covers one class of drawn property:

• position — x and y, and every other coordinate-space quantity (bar widths, angles, path vertices, text rotation). It also decides when discrete attributes flip, since those snap at the halfway point.

• color — color and fill, including per-element fills.

• size — size, linewidth, and radii.

• alpha — opacity, and the fade of marks entering or leaving a state.

position covers x and y together: the engine has a single positional curve, so the two axes cannot be eased apart.

colour

An alias for color; supplying both is an error.

Value

The modified PlotSpec.

See also

transition_states(), animate()

Examples

vplot(mtcars) |>
  mark_point(x = wt, y = mpg) |>
  transition_states(cyl) |>
  ease_aes("cubic-in-out")


# Marks settle into place gently, but the colour crossfade stays even.
vplot(mtcars) |>
  mark_point(x = wt, y = mpg, color = factor(gear)) |>
  transition_states(cyl) |>
  ease_aes("cubic-in-out", color = "linear")