In MrMallIronmaker/dddr: Three-Dimensional Spatial Operations in R

About

The R package dddr is a vctrs-based package for working with three-diensional spatial data. It gives three-dimensional objects like points, velocities, and rotations first-class vector status in R, enabling usage as column types within data.frame and tibble.

In contrast to most spatial R packages like sf or rspatial that work with geographic, 2-dimensional data, dddr works best with 3-dimensional data. The origin of this package was to analyze behavioral data (e.g, hand motion, head direction) in studies of virtual and augmented reality.

Quick View

library(tidyverse)
library(dddr)

spiral <- tibble(i = seq(0, 10*pi, 0.05)) %>%
  mutate(
    # vector3s are created using three numeric vector arguments,
    # and thanks to dplyr, can refer to other columns in the dataframe
    circular_part = vector3(x=cos(i), y=sin(i), z=0),
    forward_part = vector3(x=0, y=0, z=i/15),
    # vector3s can be added together and multiplied by numerics 
    spiral_part = circular_part * i / 30 + forward_part
  )

spiral %>% head(10)

spiral %>%
  # field access uses the $ operator
  ggplot(aes(vector3=spiral_part)) +
  stat_point3(geom="point") +
  #geom_path3() +
  coord_look_at_front()

spiral %>%
  mutate(
    # rotations can be specified using quaternions, axis / angle, or even from / to vectors
    spiral_rotated = rotate(spiral_part, axis=vector3(0, 1, 0), angle=pi/4)
  ) %>% 
  ggplot(aes(x=spiral_rotated$x, y=spiral_rotated$y)) +
  geom_point() +
  geom_path() +
  coord_equal()

Plotting

```{R eval=FALSE} simple_dddr_plot <- function() { spiral <- tibble(i = seq(0, 10*pi, 0.05)) %>% mutate( circular_part = vector3(x=cos(i), y=sin(i), z=i/15), forward_part = vector3(x=0, y=0, z=i/15), spiral_part = circular_part * i / 30 + forward_part )

spiral %>% ggplot() + stat_point3(aes(vector3=spiral_part)) + coord_look_at_front() }

# Installation

```{R, eval=FALSE}
install.packages("devtools") # if you have not installed "devtools" package
# For the most recent packaged & released version
devtools::install_github("MrMallIronmaker/dddr@*release")
# For the development version
devtools::install_github("MrMallIronmaker/dddr")

Questions

If you have questions in how to use this library, what this library is useful for, or if it has any particular features, it would be helpful to contact me directly at mrmillr at stanford.edu. This project is in its early development stages, and I want to know how you want to use the library / are using the library.