refactor: use sf_use_s2 to decide how to summarise polygons 🚧

loreabad6 · Sep 19, 2024 · fe69fad · fe69fad
1 parent ec56ccc
commit fe69fad
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Showing 3 changed files with 11 additions and 4 deletions.
diff --git a/NAMESPACE b/NAMESPACE
@@ -74,6 +74,7 @@ importFrom(rlang,`%||%`)
 importFrom(rlang,sym)
 importFrom(sf,`st_crs<-`)
 importFrom(sf,`st_geometry<-`)
+importFrom(sf,sf_use_s2)
 importFrom(sf,st_agr)
 importFrom(sf,st_as_sf)
 importFrom(sf,st_as_sfc)

diff --git a/R/summarise_geometry.R b/R/summarise_geometry.R
@@ -61,7 +61,7 @@ summarize_geometry_union = summarise_geometry_union
 #' @describeIn summarise_geometry computes the geometry summary as the centroid
 #' of the union and dissolve of the changing geometries
 #' @inheritParams summarise_geometry_union
-#' @importFrom sf st_centroid
+#' @importFrom sf st_centroid sf_use_s2
 #' @export
 summarise_geometry_centroid = function(x,
                                        group_id = NULL,
@@ -70,7 +70,7 @@ summarise_geometry_centroid = function(x,
   x_unioned = st_summarise_polys(x,
                                  group_id = group_id,
                                  sf_column_name = sf_column_name,
-                                 do_union = TRUE,
+                                 do_union = sf::sf_use_s2(),
                                  .checks = .checks)
   x_centroid = sf::st_centroid(x_unioned)
   x_centroid
@@ -108,6 +108,7 @@ summarise_geometry_bbox = function(x,
 }
 
 #' @rdname summarise_geometry
+#' @importFrom sf st_convex_hull sf_use_s2
 #' @export
 summarize_geometry_bbox = summarise_geometry_bbox
 
@@ -123,7 +124,7 @@ summarise_geometry_convex_hull = function(x,
   x_unioned = st_summarise_polys(x,
                                  group_id = group_id,
                                  sf_column_name = sf_column_name,
-                                 do_union = TRUE,
+                                 do_union = sf::sf_use_s2(),
                                  .checks = .checks)
   x_conv_hull = sf::st_convex_hull(x_unioned)
   x_conv_hull

diff --git a/R/utils.R b/R/utils.R
@@ -47,7 +47,8 @@ st_bbox_by_feature = function(x) {
 #' @noRd
 #' @importFrom sf st_make_valid st_cast st_union
 st_summarise_polys = function(x, group_id, sf_column_name,
-                              do_union = TRUE, .checks = TRUE) {
+                              do_union = sf::sf_use_s2(),
+                              .checks = TRUE) {
 
   if(.checks){
     # group_id: Defaults to the first column of x, if not sfc or temporal class
@@ -66,6 +67,10 @@ st_summarise_polys = function(x, group_id, sf_column_name,
   }
 
   x_groupped = split(x[[sf_column_name]], x[[group_id]])
+  # Combining all the polygon features into one single polygon is a much
+  # cheaper operation than doing a union operation.
+  # However the validity of the multipolygon will throw errors with s2 geometry
+  # so the default is to union when s2 is active in sf
   if(do_union) {
     do.call(
       "c",