Points drawn from the shapes font

geom_point_glyph() is ggplot2::geom_point() for the shape palettes made with unicode = TRUE. It draws their shapes from the font that ships with ggthemes (see register_shapes_font()), reading the font file itself, so the shapes come out at a common size without setting a font family on the device or a viewport, and the plot can be saved with ggplot2::ggsave().

Usage

geom_point_glyph(
  mapping = NULL,
  data = NULL,
  stat = "identity",
  position = "identity",
  ...,
  na.rm = FALSE,
  show.legend = NA,
  inherit.aes = TRUE
)

Arguments

mapping

Set of aesthetic mappings created by 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. A function can be created from a formula (e.g. ~ head(.x, 10)).

stat

The statistical transformation to use on the data for this layer. When using a geom_*() function to construct a layer, the stat argument can be used to override the default coupling between geoms and stats. The stat argument accepts the following:

A Stat ggproto subclass, for example StatCount.
A string naming the stat. To give the stat as a string, strip the function name of the stat_ prefix. For example, to use stat_count(), give the stat as "count".
For more information and other ways to specify the stat, see the layer stat documentation.

position

A position adjustment to use on the data for this layer. This can be used in various ways, including to prevent overplotting and improving the display. The position argument accepts the following:

The result of calling a position function, such as position_jitter(). This method allows for passing extra arguments to the position.
A string naming the position adjustment. To give the position as a string, strip the function name of the position_ prefix. For example, to use position_jitter(), give the position as "jitter".
For more information and other ways to specify the position, see the layer position documentation.

...

Other arguments passed on to layer()'s params argument. These arguments broadly fall into one of 4 categories below. Notably, further arguments to the position argument, or aesthetics that are required can not be passed through .... Unknown arguments that are not part of the 4 categories below are ignored.

Static aesthetics that are not mapped to a scale, but are at a fixed value and apply to the layer as a whole. For example, colour = "red" or linewidth = 3. The geom's documentation has an Aesthetics section that lists the available options. The 'required' aesthetics cannot be passed on to the params. Please note that while passing unmapped aesthetics as vectors is technically possible, the order and required length is not guaranteed to be parallel to the input data.
When constructing a layer using a stat_*() function, the ... argument can be used to pass on parameters to the geom part of the layer. An example of this is stat_density(geom = "area", outline.type = "both"). The geom's documentation lists which parameters it can accept.
Inversely, when constructing a layer using a geom_*() function, the ... argument can be used to pass on parameters to the stat part of the layer. An example of this is geom_area(stat = "density", adjust = 0.5). The stat's documentation lists which parameters it can accept.
The key_glyph argument of layer() may also be passed on through .... This can be one of the functions described as key glyphs, to change the display of the layer in the legend.

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. To include legend keys for all levels, even when no data exists, use TRUE. If NA, all levels are shown in legend, but unobserved levels are omitted.

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. annotation_borders().

Value

A ggplot2 layer.

Devices

A device that can draw glyphs from a font file draws the shapes that way. That needs R 4.3 or later and a device that reports dev.capabilities()$glyphs, such as pdf(), the ragg devices and the quartz devices. Other devices, such as postscript() and svglite, draw the shapes as ordinary points in the font family "ggthemes shapes", which ggthemes registers with systemfonts when it loads. Devices that read fonts through systemfonts find it there; the rest fall back to their own fonts.

pdf() refers to the font without embedding it, so the file draws the shapes only where the font is installed. embed_shapes_font() embeds it.

Shapes the font does not have, such as the pictographs of tableau_shape_pal("weather", unicode = TRUE), and base pch shapes are drawn as ggplot2::geom_point() draws them.

Calling geom_point_glyph() tells the unicode = TRUE palettes that the shapes font is in use, so they stop warning about shapes it has, for every plot in the session, including plots drawn with ggplot2::geom_point(). That lasts until ggthemes is unloaded, for example by restarting R or with unloadNamespace("ggthemes").

Aesthetics

The aesthetics of ggplot2::geom_point(): x, y, alpha, colour, fill, shape, size and stroke. A shape drawn from the font is a single solid glyph, so fill applies only to base pch shapes 21 to 25.

Examples

library(ggplot2)

# geom_point_glyph() reads the font with the systemfonts package.
if (rlang::is_installed("systemfonts")) {
  # The five symbols of Cleveland's set for little overlap, drawn from the
  # shapes font at a common size. `cut` has five levels, one per symbol.
  diamonds_sample <- head(diamonds, 200)
  ggplot(diamonds_sample, aes(x = carat, y = price, shape = cut)) +
    geom_point_glyph(size = 3) +
    scale_shape_cleveland(overlap = FALSE, unicode = TRUE)

  # Arrows have no base pch, so they need `unicode = TRUE`.
  directions <- data.frame(x = 1:8, y = 1, direction = factor(1:8))
  ggplot(directions, aes(x, y, shape = direction)) +
    geom_point_glyph(size = 8) +
    scale_shape_tableau("arrows", unicode = TRUE) +
    theme_void() +
    theme(legend.position = "none")
}