R/snowcrab_mapping_features.R

In jae0/snowcrab: Snow crab assessment suite for aegis* and associated projects.

snowcrab_mapping_features = function( p, 
  area_lines=NULL, 
  isobaths=c( 100, 200, 300, 400, 500 ), 
  coastline=c("Canada", "United States of America"), 
  xlim=c(-85,-35), ylim=c(35, 65),
  redo=FALSE, target=c("ggplot", "tmap")  ) {

    # same as carstm::features-to_add, but with different defaults

    fn = file.path( p$project.outputdir, "snowcrab_mapping_features.RDS" )
    if (!redo){
      O = NULL
      if (file.exists(fn)) O = readRDS(fn)
      if (!is.null(O)) return(O)
    }

    plot_crs = p$aegis_proj4string_planar_km
     
    rg = NULL
    if (!is.null(area_lines )) {
      rg = aegis.polygons::area_lines.db( DS=area_lines, returntype="sf", project_to=plot_crs )
    }

    z = NULL
    if (!is.null(isobaths)) {
      z = aegis.bathymetry::isobath_db( depths=isobaths, project_to=plot_crs )
    }

    rg = aegis.polygons::area_lines.db( DS="cfa.regions", returntype="sf", project_to=plot_crs )
    
    cl = NULL
    if (!is.null(coastline)) {
      # coastline =  c("unsited states of america", "canada")
      cl = st_transform( polygons_rnaturalearth(countries=coastline, xlim=xlim, ylim=ylim), st_crs(plot_crs) )
    }
 
    O = list()

    if ("ggplot" %in% target) {
      require(ggplot2)

      O[["ggplot"]] =  ggplot() +
        geom_sf( data=z,  fill=NA, col = "slategray",  lwd=0.25) +
        geom_sf( data=rg, fill=NA, col = "slategray",  lwd=2.0) + 
        geom_sf( data=cl, fill=NA, col = "slategray", lwd=0.5)
    }

    if ("tmap" %in% target) {
      require(tmap)

      O[["tmap"]] =  
        tm_shape( z,  projection=plot_crs ) + tm_lines( col="slategray", alpha=0.5, lwd=0.2) +
        tm_shape( rg, projection=plot_crs ) + tm_lines( col="slategray", alpha=0.75, lwd=2)   + 
        tm_shape( cl, projection=plot_crs ) + tm_borders( col = "slategray", alpha=0.5, lwd=0.5)
    }

    dir.create( p$project.outputdir, showWarnings = FALSE, recursive = TRUE )
    saveRDS( O, file=fn, compress=TRUE )
    return(O)
}