ob_bezier: The ob_bezier (i.e., bezier curve) class

In ggdiagram: Object-Oriented Diagram Plots with 'ggplot2'

The ob_bezier (i.e., bezier curve) class

Description

The ob_bezier is specified with an ob_point object that contains at least 2 points, the start and the end. Such a "curve" would actually be a straight line segment. If three points are specified, the middle point is a control point, and a quadratic bezier curve will result. Higher-order bezier curves can be created by having more control points in the middle.

Usage

ob_bezier(
  p = S7::class_missing,
  label = character(0),
  label_sloped = TRUE,
  n = 100,
  alpha = numeric(0),
  arrow_head = S7::class_missing,
  arrow_fins = S7::class_missing,
  arrowhead_length = numeric(0),
  length_head = numeric(0),
  length_fins = numeric(0),
  color = character(0),
  fill = character(0),
  lineend = numeric(0),
  linejoin = numeric(0),
  linewidth = numeric(0),
  linewidth_fins = numeric(0),
  linewidth_head = numeric(0),
  linetype = numeric(0),
  resect = numeric(0),
  resect_fins = numeric(0),
  resect_head = numeric(0),
  stroke_color = character(0),
  stroke_width = numeric(0),
  style = S7::class_missing,
  id = character(0),
  ...
)

Arguments

p	ob_point or list of ob_points
label	A character, angle, or label object
label_sloped	A logical value indicating whether the label should be sloped with the curve
n	Number of points in a polygon, circle, arc, or ellipse
alpha	numeric value for alpha transparency
arrow_head	A 2-column matrix of polygon points
arrow_fins	A 2-column matrix of polygon points
arrowhead_length	Determines the size of the arrow ornaments. This parameter becomes the length parameter in ggarrow functions. Numeric values set the ornament size relative to the linewidth. A grid::unit value sets the ornament size in an absolute manner.
length_head	Determines the size of the arrow head. Numeric values set the ornament size relative to the linewidth. A grid::unit value sets the ornament size in an absolute manner. From ggarrow.
length_fins	Determines the size of the arrow fins. Numeric values set the ornament size relative to the linewidth. A grid::unit value sets the ornament size in an absolute manner. From ggarrow.
color	character string for color
fill	character string for fill color
lineend	Line end style (round, butt, square).
linejoin	Line join style (round, mitre, bevel).
linewidth	Width of lines
linewidth_fins	Line width for arrow fins
linewidth_head	Line width for arrow fins
linetype	type of lines
resect	A numeric(1) denoting millimeters or grid::unit to shorten the arrow head and fins.
resect_fins	A numeric(1) denoting millimeters or grid::unit to shorten the arrow fins
resect_head	A numeric(1) denoting millimeters or grid::unit to shorten the arrow head.
stroke_color	Color of point border line
stroke_width	Stroke width in arrows
style	Gets and sets the styles associated with ob_beziers
id	character string to identify object
...	<dynamic-dots> properties passed to style

Details

If you wish to specify multiple bezier curves, you must supply a list of ob_point objects. When plotted, the ob_bezier function uses the bezier::bezier function to create the point coordinates of the curve and the ggarrow::geom_arrow function to create the geom.

Value

ob_bezier object

Slots

length

The number of curves in the ob_bezier object

tibble

Gets a tibble (data.frame) containing parameters and styles used by ggarrow::geom_arrow.

geom

A function that converts the object to a geom. Any additional parameters are passed to ggarrow::geom_arrow.

midpoint

A function that selects 1 or more midpoints of the ob_bezier. The position argument can be between 0 and 1. Additional arguments are passed to ob_point.

aesthetics

A list of information about the ob_bezier's aesthetic properties

Examples

control_points <- ob_point(c(0,1,2,4), c(0,4,0,0))
ggdiagram() +
  ob_bezier(control_points, color = "blue")

ggdiagram documentation built on Sept. 15, 2025, 1:07 a.m.