In coolbutuseless/ggthreed: Threed Geoms and Stats for Ggplot2

suppressPackageStartupMessages({
  library(ggplot2)
  library(threed)
  library(ggthreed)
})

knitr::opts_chunk$set(
  collapse = TRUE,
  comment = "#>", 
  fig.width = 6
)

library(ggplot2)
library(threed)
library(ggthreed)

Usage

• Requires only an x variable - which must be discrete.
• Default stat is count
• Adjustable parameters:
  • camera position
  • pie height
  • starting angle for first pie slice
  • tilt angle of pie relative to camera

Issues/Limitations

• geom_threedpie() overrides the aspect ratio of the plot it is displaying. This is a gigantic hack! It means it is not possible to use coord_fixed() etc to change the plot aspec ratio.
• The initial panel grid and x- and y-axes are still generated by the geom. Currently the only way to turn this off it to use theme_void(). Not sure how to disable this from within the geom.
• Pie slice resolution is in increments of 2 degrees.

Example - Simple Pie Chart

ggplot(mtcars) + 
  geom_threedpie(aes(x = as.factor(cyl))) + 
  theme_void() + 
  theme(legend.position = 'bottom')

Example - Facetted Pie Chart

ggplot(diamonds)  +
  geom_threedpie(aes(as.factor(cut))) +
  facet_wrap(~clarity, labeller = label_both) +
  labs(title = "Distribution of Diamond Cuts by Clarity") +
  scale_fill_brewer(name = "Cut", palette = 'Set2') +
  theme_void()

Example - Behind the Scenes

• This plot shows the polygons making up the pie.
• Triangular polygons are rendered on top, and quadrilaterals are rendered for the side.
• The threed library is used to rotate the assembled polygons and perform perspective projection.
• By plotting the polygons in order of distance from the camera (furtherest polygons first), polygons which are behind others are hidden from view.
• The pie has no bottom.
• The quadrilaterals making up the side are the same colour as the top, but darkened by 15%.

ggplot(mtcars) + 
  geom_threedpie(aes(x = as.factor(cyl)), alpha = 0.5) + 
  theme_void() + 
  theme(legend.position = 'bottom')

coolbutuseless/ggthreed documentation built on May 16, 2019, 7:14 p.m.