geom_bezier: Create quadratic or cubic bezier curves [copied from ggforce]

Description Usage Arguments Details Aesthetics Computed variables Author(s) Examples

View source: R/ggforce_bezier.R

Description

This set of functionality is copied from ggforce package due to dependency issues on Bioconductor and is used internally (not exported) only. This set of geoms makes it possible to connect points creating either quadratic or cubic beziers. bezier works by calculating points along the bezier and connecting these to draw the curve.

Usage

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stat_bezier(mapping = NULL, data = NULL, geom = "path",
  position = "identity", na.rm = FALSE, show.legend = NA, n = 100,
  inherit.aes = TRUE, ...)

geom_bezier(mapping = NULL, data = NULL, stat = "bezier",
  position = "identity", arrow = NULL, lineend = "butt",
  na.rm = FALSE, show.legend = NA, inherit.aes = TRUE, n = 100,
  ...)

Arguments

mapping

Set of aesthetic mappings created by aes() or aes_(). If specified and inherit.aes = TRUE (the default), it is combined with the default mapping at the top level of the plot. You must supply mapping if there is no plot mapping.

data

The data to be displayed in this layer. There are three options:

If NULL, the default, the data is inherited from the plot data as specified in the call to ggplot().

A data.frame, or other object, will override the plot data. All objects will be fortified to produce a data frame. See fortify() for which variables will be created.

A function will be called with a single argument, the plot data. The return value must be a data.frame, and will be used as the layer data.

geom

The geometric object to use display the data

position

Position adjustment, either as a string, or the result of a call to a position adjustment function.

na.rm

If FALSE, the default, missing values are removed with a warning. If TRUE, missing values are silently removed.

show.legend

logical. Should this layer be included in the legends? NA, the default, includes if any aesthetics are mapped. FALSE never includes, and TRUE always includes. It can also be a named logical vector to finely select the aesthetics to display.

n

The number of points to create for each segment

inherit.aes

If FALSE, overrides the default aesthetics, rather than combining with them. This is most useful for helper functions that define both data and aesthetics and shouldn't inherit behaviour from the default plot specification, e.g. borders().

...

Other arguments passed on to layer(). These are often aesthetics, used to set an aesthetic to a fixed value, like colour = "red" or size = 3. They may also be parameters to the paired geom/stat.

stat

The statistical transformation to use on the data for this layer, as a string.

arrow

Arrow specification, as created by grid::arrow().

lineend

Line end style (round, butt, square).

Details

Input data is understood as a sequence of data points the first being the start point, then followed by one or two control points and then the end point. More than 4 and less than 3 points per group will throw an error.

Aesthetics

geom_link, geom_link2 and geom_lin0 understand the following aesthetics (required aesthetics are in bold):

- **x** - **y** - color - size - linetype - alpha - lineend

Computed variables

x, y

The interpolated point coordinates

index

The progression along the interpolation mapped between 0 and 1

Author(s)

Thomas Lin Pedersen

Examples

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beziers <- data.frame(
    x = c(1, 2, 3, 4, 4, 6, 6),
    y = c(0, 2, 0, 0, 2, 2, 0),
    type = rep(c('cubic', 'quadratic'), c(3, 4)),
    point = c('end', 'control', 'end', 'end', 'control', 'control', 'end')
)
help_lines <- data.frame(
    x = c(1, 3, 4, 6),
    xend = c(2, 2, 4, 6),
    y = 0,
    yend = 2
)
ggplot2::ggplot() + ggplot2::geom_segment(
  ggplot2::aes(x = x, xend = xend, y = y, yend = yend),
  data = help_lines,
  arrow = ggplot2::arrow(length = ggplot2::unit(c(0, 0, 0.5, 0.5), 'cm')),
  colour = 'grey') +
  amplican:::geom_bezier(ggplot2::aes(x= x, y = y, group = type, linetype = type),
              data = beziers) +
  ggplot2::geom_point(ggplot2::aes(x = x, y = y, colour = point), data = beziers)

amplican documentation built on Nov. 8, 2020, 11:10 p.m.