#30DayMapChallenge 2022 | Day 26 | Islands

day_26_islands.R

# Plonk the largest islands together on the page
# I was going to both make these to scale, and animate between them, but
# didn't have enough time up my sleeve.

library(glue)
library(dplyr)
library(sf)
library(rnaturalearth)
library(ggplot2)
library(patchwork)

world <- 
  ne_countries(scale = "large", type = "map_units", returnclass = "sf")

CRS_00 <- "+proj=ortho +lon_0=0 +lat_0=0"
COL_LAND <- "light green"
COL_BG <- "light blue"
COL_TEXT <- "black"
MAP_FONT <- "BellTopo Sans"

project_and_play <- 
  function(island_geo) {
    merc_centroid <- 
      island_geo |> 
      st_centroid()
    merc_coords <- 
      merc_centroid |> 
      st_coordinates()
    projection <- 
      glue("+proj=ortho +lon_0={merc_coords[1, 'X']} +lat_0={merc_coords[1, 'Y']}")
    projected_island <- 
      island_geo |> 
      st_transform(crs = projection)
    projected_centroid <- 
      projected_island |> 
      st_centroid()
    list(
      island = projected_island,
      centroid = projected_centroid,
      projection = projection
    )
  }

map_island <- 
  function(island_list) {
    ggplot() +
      geom_sf(data = island_list$island,
              fill = COL_LAND, colour = NA) +
      geom_sf_text(data = island_list$centroid,
                   aes(label = island),
                   family = MAP_FONT,
                   size = 12,
                   colour = COL_TEXT) +
      theme_void() +
      theme(plot.background = element_rect(fill = COL_BG, colour = COL_BG))
  }

# Greenland ----
greenland <- 
  world |> 
  filter(admin == "Greenland") |> 
  select(island = admin) |> 
  st_cast("POLYGON") |>
  slice(1) |> 
  project_and_play()
gg_greenland <- 
  greenland |> map_island()
# New Guinea ----
new_guinea <- 
  bind_rows(
    world |> 
      filter(geounit == "Papua New Guinea") |> 
      transmute(island = "New Guinea") |> 
      st_cast("POLYGON") |> 
      slice(1),
    world |> 
      filter(sovereignt == "Indonesia") |> 
      transmute(island = "New Guinea") |> 
      st_cast("POLYGON") |> 
      slice(4)
  ) |> 
  count(island) |> 
  select(-n) |> 
  project_and_play()
gg_new_guinea <- 
  new_guinea |> map_island()

# Borneo ----
borneo <-
  bind_rows(
    world |> 
      filter(sovereignt == "Brunei") |> 
      transmute(island = "Borneo") |> 
      st_cast("POLYGON"),
    world |> 
      filter(sovereignt == "Malaysia") |> 
      transmute(island = "Borneo") |> 
      st_cast("POLYGON") |> 
      slice(3),
    world |> 
      filter(sovereignt == "Indonesia") |> 
      transmute(island = "Borneo") |> 
      st_cast("POLYGON") |> 
      slice(3)
  ) |> 
  count(island) |> 
  select(-n) |> 
  project_and_play()
gg_borneo <- 
  borneo |> map_island()

# Madagascar ----
madagascar <- 
  world |> 
  filter(sovereignt == "Madagascar") |> 
  select(island = sovereignt) |> 
  st_cast("POLYGON") |> 
  slice(1) |> 
  project_and_play()
gg_madagascar <- 
  madagascar |> map_island()

# Baffin Island ----
baffin <-
  world |> 
  filter(sovereignt == "Canada") |> 
  transmute(island = "Baffin Island") |> 
  st_cast("POLYGON") |> 
  # mutate(order1 = row_number(), larea = st_area(geometry)) |> arrange(desc(larea))
  # 1, 125, 124, 2, 282, 17«
  slice(125) |> 
  project_and_play()
gg_baffin <- 
  baffin |> map_island()

# Sumatra ----
sumatra <- 
  world |> 
  filter(sovereignt == "Indonesia") |> 
  transmute(island = "Sumatra") |> 
  st_cast("POLYGON") |> 
  slice(59)  |> 
  project_and_play()
gg_sumatra <- 
  sumatra |> map_island()

# Honshu ----
honshu <-
  world |> 
  filter(sovereignt == "Japan") |> 
  transmute(island = "Honshū") |> 
  st_cast("POLYGON") |> 
  slice(7) |> 
  project_and_play()
gg_honshu <- 
  honshu |> map_island()

# Victoria Island ----
victoria <- 
  world |> 
  filter(sovereignt == "Canada") |> 
  transmute(island = "Victoria Island") |> 
  st_cast("POLYGON") |> 
  slice(124) |> 
  project_and_play()
gg_victoria <- 
  victoria |> map_island()

# Great Britain  ----
britain <- 
  bind_rows(
    world |> 
      filter(geounit == "Wales") |> 
      transmute(island = "Great Britain") |> 
      st_cast("POLYGON") |> 
      slice(1),
    world |> 
      filter(geounit == "Scotland") |> 
      transmute(island = "Great Britain") |> 
      st_cast("POLYGON") |> 
      slice(1),
    world |> 
      filter(geounit == "England") |> 
      transmute(island = "Great Britain") |> 
      st_cast("POLYGON") |> 
      slice(1)
  ) |> 
  count(island) |> 
  select(-n) |> 
  project_and_play()
gg_britain <- 
  britain |> map_island()

# Ellesmere Island ----
ellesmere <- 
  world |> 
  filter(sovereignt == "Canada") |> 
  transmute(island = "Ellesmere Island") |> 
  st_cast("POLYGON") |> 
  slice(282) |> 
  project_and_play()
gg_ellesmere <- 
  ellesmere |> map_island()

# Sulawesi ----
sulawesi <-
  world |> 
  filter(sovereignt == "Indonesia") |> 
  transmute(island = "Sulawesi") |> 
  st_cast("POLYGON") |> 
  slice(56) |> 
  project_and_play()
gg_sulawesi <- 
  sulawesi |> map_island()

# South Island ----
south <- 
  world |> 
  filter(subunit == "New Zealand") |> 
  transmute(island = "Te Waipounamu") |> 
  st_cast("POLYGON") |> 
  slice(17) |> 
  project_and_play()
gg_south <- 
  south |> map_island()


gg_greenland +
  (gg_new_guinea / gg_borneo / gg_madagascar) +
  ((gg_baffin + gg_sumatra + gg_honshu + gg_victoria) /
     (gg_britain + gg_ellesmere + gg_sulawesi + gg_south)) +
  plot_annotation(title = "The Twelve Largest Islands",
                  subtitle = "Approximately: 1 = (2 + 3 + 4) = (5 + 6 + 7 + 8 + 9 + 10 + 11 + 12)",
                  caption = "Note: islands not to scale",
                  theme = theme(plot.title = element_text(size = 96, family = MAP_FONT, colour = COL_TEXT, hjust = 0.5, margin = margin(c(20, 0, 10, 0))),
                                plot.subtitle = element_text(size = 48, family = MAP_FONT, colour = COL_TEXT, hjust = 0.5),
                                plot.caption = element_text(size = 32, family = MAP_FONT, colour = COL_TEXT, hjust = 0.95, margin = margin(c(60, 40, 0, 0))))) &
  theme(plot.background = element_rect(fill = COL_BG, colour = COL_BG),
        panel.background = element_rect(fill = COL_BG, colour = COL_BG))

ggsave(path = "Day_26_Islands", filename = "day_26_islands.png",
       width = 36, height = 26, dpi = 72)