Fix undesirable artefacts during map zooming/cropping for some CRS

R/compilation.R

@@ -464,8 +464,8 @@ slim <- function(
     -d 'OUTPUT_LOCATIONS=\"%s\"' \\
     -d COALESCENT_ONLY=%s \\
     -d MAX_ATTEMPTS=%i \\
-    %s",
-      binary,
+    %s 2>&1",
+      binary, # path to the SLiM binary on the command line
       seed,
       samples,
       path.expand(model_dir),
@@ -490,7 +490,7 @@ slim <- function(
 
     # execute the command, capture all log output and decide whether to print
     # any of the log information to the console
-    log_output <- suppressWarnings(system(paste(slim_command, "2>&1"), intern = TRUE))
+    log_output <- suppressWarnings(system(slim_command, intern = TRUE))
     log_warnings <- grep("WARNING", log_output, value = TRUE)
     if (verbose)
       cat(log_output, sep = "\n")

R/interface.R

@@ -730,19 +730,18 @@ world <- function(xrange, yrange, landscape = "naturalearth", crs = NULL,
     )
     sf::st_agr(map_raw) <- "constant"
 
-    ## transform the map (default geographic CRS) into the target CRS
-    map_transf <- tryCatch({
-      sf::st_transform(map_raw, crs) %>% sf::st_make_valid()
+    # define boundary coordinates in the target CRS
+    crop_bounds <- define_zoom(xrange, yrange, "EPSG:4326")
+
+    # crop the map to the boundary coordinates
+    map_cropped <- tryCatch({
+      sf::st_crop(sf::st_make_valid(map_raw), crop_bounds)
     }, error = function(cond) {
-      sf::st_transform(map_raw, crs)
+      sf::st_crop(map_raw, crop_bounds)
     })
 
-    ## define boundary coordinates in the target CRS
-    zoom_bounds <- define_zoom(xrange, yrange, "EPSG:4326")
-    zoom_transf <- sf::st_transform(zoom_bounds, crs) %>% sf::st_make_valid()
-
-    ## crop the map to the boundary coordinates
-    map <- sf::st_crop(map_transf, zoom_transf)
+    # transform the map into the target CRS if needed
+    map <- sf::st_transform(map_cropped, crs)
   } else {
     stop("Landscape has to be either 'blank', 'naturalearth' or an object of the class 'sf'",
          call. = FALSE)

README.Rmd

@@ -130,7 +130,7 @@ This makes it easier for us to define spatial features simply by reading the coo
 africa <- region(
   "Africa", map,
   polygon = list(c(-18, 20), c(38, 20), c(30, 33),
-                 c(20, 33), c(10, 38), c(-6, 36))
+                 c(20, 33), c(10, 38), c(-6, 35))
 )
 europe <- region(
   "Europe", map,

README.md

@@ -121,7 +121,7 @@ This makes it easier for us to define spatial features simply by reading the coo
 africa <- region(
   "Africa", map,
   polygon = list(c(-18, 20), c(38, 20), c(30, 33),
-                 c(20, 33), c(10, 38), c(-6, 36))
+                 c(20, 33), c(10, 38), c(-6, 35))
 )
 europe <- region(
   "Europe", map,