inst/workflow_example/01_spatial_data_preparation.R

In nevrome/bleiglas: Spatiotemporal Data Interpolation and Visualisation based on 3D Tessellation

library(magrittr)

#### define crs ####

epsg102013 <- paste(
  "+proj=aea +lat_1=43 +lat_2=62 +lat_0=30",
  "+lon_0=10 +x_0=0 +y_0=0 +ellps=intl +units=m +no_defs"
)

save(epsg102013, file = "inst/workflow_example/epsg102013.RData")

#### load research area ####

# load manually crafted research area shape file
research_area <- sf::st_read(
  "inst/workflow_example/research_area_shapefile/research_area.shp", 
  quiet = TRUE
) %>%
  # transform it to EPSG:102013
  sf::st_transform(epsg102013)

save(research_area, file = "inst/workflow_example/research_area.RData")

#### download and prepare land outline ####

# download land outline from natural earth data service
land_outline <- rnaturalearth::ne_download(
  scale = 50, type = 'land', category = 'physical',
  returnclass = "sf"
)

land_outline_small <- land_outline %>%
  # crop it approximately to Europe
  sf::st_crop(xmin = -20, ymin = 35, xmax = 35, ymax = 65) %>%
  # transform it to EPSG:102013
  sf::st_transform(epsg102013)

# crop land outline to enlarged bbox of research area
bb <- sf::st_bbox(research_area)
bb[1:2] <- bb[1:2] - 200000
bb[3:4] <- bb[3:4] + 200000
extended_research_area <- bb %>% sf::st_as_sfc()
extended_area <- sf::st_intersection(
  sf::st_buffer(land_outline_small, 0), 
  extended_research_area
)

save(extended_area, file = "inst/workflow_example/extended_area.RData")