Chapter 2 Getting Set Up

NOTE: throughout these pages are calls to the rglwidget() function, which is necessary for putting these 3D plots into view for this document and when using RStudio Server. For normal installations of R you can avoid running this function.

We suggest use of the package remotes which will avoid re-installing a package if the latest version is already installed.

if (!requireNamespace("remotes")) install.packages("remotes")

pkgs <- c("ceramic", "colourvalues", "dplyr", "quadmesh", "raster", "rgl", "rgdal", "scales", "sf", "sfdct", 
 "spex", "tidyr", "viridis")

remotes::install_cran(pkgs)

In-development packages from Github:

remotes::install_github(c("hypertidy/silicate", "hypertidy/anglr", "AustralianAntarcticDivision/raadtools"))

Obtain some extra data sets that will be used in this session.

download.file("https://github.com/mdsumner/geo-comp-graphics-oghub/raw/master/data-raw/geo-comp-graphics.Rdata", 
               "geo-comp-graphics.Rdata", mode = "wb")

load("geo-comp-graphics.Rdata")


## a world image (Blue Marble)
bm_url <- "https://eoimages.gsfc.nasa.gov/images/imagerecords/73000/73909/world.topo.bathy.200412.3x5400x2700.jpg"
bm_file <- basename(bm_url)
if (!file.exists(bm_file)) download.file(bm_url, bm_file)

Miscellaneous functions used to build the examples.

colpal <- function(n = 26, drop = 5) sf::sf.colors(n)[-seq_len(drop)]
plot_values <- function(x) {
  raster::plot(x, axes = FALSE, main = "value", box = FALSE, col = colpal()); 
  text(coordinates(x), label = values(x))
  raster::plot(extent(x), add = TRUE)
}
plot_cells <- function(x) {
  raster::plot(x, axes = FALSE, main = "cell", legend = FALSE, box = FALSE, col = colpal()); 
  raster::plot(extent(x), add = TRUE)
  text(coordinates(x), label = sprintf("[%i]", seq_len(ncell(x))), cex = 0.8)
}
plot_edges <- function(x, main = "") {
  sc <- silicate::SC(spex::polygonize(x))
  e <- silicate::sc_edge(sc)
  v <- silicate::sc_vertex(sc)
  x0 <- e %>% dplyr::inner_join(v, c(".vx0" = "vertex_"))
  x1 <- e %>% dplyr::inner_join(v, c(".vx1" = "vertex_"))
  plot(rbind(x0, x1)[c("x_", "y_")], asp = 1, type = "n", 
       axes = FALSE, xlab = "", ylab = "", main = main)
  graphics::segments(x0$x_, x0$y_, x1$x_, x1$y_, lty = 2)
}