A twisted ribbon following a random path

shape_twist is like shape_ribbon, but the underlying path is a Brownian bridge rather than a straight line, giving the polygon a wandering, twisted appearance.

shape_twists() is a vectorized version of shape_twist(): each argument may be a vector, recycled against the others via purrr::pmap()'s own vctrs-based rules. The result is a sketch containing one shape_twist() per recycled row, rather than a single drawable.

Usage

shape_twist(
  x = 0,
  y = 0,
  xend = 1,
  yend = 1,
  width = 0.2,
  n = 100L,
  path_distortion = noise_bridge(),
  distortion = noise_field(),
  trans = trans_identity(),
  ...
)

shape_twists(
  x = 0,
  y = 0,
  xend = 1,
  yend = 1,
  width = 0.2,
  n = 100L,
  path_distortion = noise_bridge(),
  distortion = noise_field(),
  trans = trans_identity(),
  ...
)

Arguments

x, y

Start point. Default 0.

xend, yend

End point. Default 1.

width

Maximum width. Must be non-negative. Default 0.2.

n

Number of points used along the path. Default 100L.

path_distortion

A noise_bridge controlling the path's Brownian bridge. Default noise_bridge().

distortion

A noise_field controlling the width modulation. Default noise_field().

trans

A trans object applied to the shape's computed points. Default trans_identity() (no transform).

...

Arguments passed to style().

Value

A drawable.

For shape_twists(), a sketch.

Details

Any length-1 element is broadcast to the common length; mismatched lengths greater than 1 raise an error. A shared path_distortion/distortion is automatically recycled across every twist; pass a list() of several different noise_bridge/noise_field objects instead to vary either per twist – as in README.Rmd's "Twists" example, which gives every twist the same path_distortion this way.

See also

Other 2D shapes: shape_bezier(), shape_blob(), shape_circle(), shape_combine(), shape_ellipse(), shape_polygon(), shape_raw(), shape_rectangle(), shape_ribbon(), shape_star(), shape_stroke(), shape_strokepath(), shape_wedge()

Examples

draw(shape_twist(
  x = 0, y = 0, xend = 1, yend = 0, width = 0.2,
  path_distortion = noise_bridge(seed = 7734)
))


# more smoothing passes make the Brownian bridge wander more gently;
# fewer passes leave it jumpier
draw(shape_twist(
  x = 0, y = 0, xend = 1, yend = 0, width = 0.2,
  path_distortion = noise_bridge(smooth = 20L, seed = 7734)
))

draw(shape_twist(
  x = 0, y = 0, xend = 1, yend = 0, width = 0.2,
  path_distortion = noise_bridge(smooth = 0L, seed = 7734)
))


draw(shape_twists(x = 1:3, y = 0, xend = 2:4, yend = 1, width = 0.2))


# every twist sharing one path_distortion gives them a family
# resemblance, as in README.Rmd's "Twists" example
draw(shape_twists(
  x = 0, y = 1:5, xend = 3, yend = 1:5, width = 0.15,
  path_distortion = noise_bridge(seed = 2020)
))