From 3180a86ee71579c9b31822e006a05b37069c70d4 Mon Sep 17 00:00:00 2001 From: Jeremy Kidwell Date: Thu, 31 Mar 2022 10:59:31 +0100 Subject: [PATCH] more coherent variable names --- script.R | 101 +++++++++++++++++++++++++++++++++++++++++-------------- 1 file changed, 75 insertions(+), 26 deletions(-) diff --git a/script.R b/script.R index 1c1855b..000c2ff 100755 --- a/script.R +++ b/script.R @@ -12,35 +12,84 @@ buildings <- st_read("./data/OS_Open_Zoomstack_district_buildings.gpkg") # open country shapefiles countries <- st_read("data/infuse_ctry_2011.shp") -# Create modest buffer around quite small building polygons for the sake of visualisation at very large scale where small polygons can appear as points -buffer <- st_buffer(buildings,150) -# Dissolve and merge overlapping shapes -union <- st_union(buffer) -# Generate a masking layer, with filled space for unoccupied layers -difference <- st_difference(local_authorities$geom, union) -# Write results to a file: -st_write(difference, "data/local_authorities_cropped_union_buffer_150.gpkg") -# Invert polygons in this new layer -inversion <- st_difference(local_authorities$geom, difference) -# Write results to a file: -st_write(inversion, "data/local_authorities_cropped_union_buffer_150_inverted.gpkg") -# Create simplified version: -inversion_simplified = st_simplify(inversion, dTolerance = 150) # 150 m -st_write(inversion_simplified, "data/local_authorities_cropped_union_buffer_150_inverted_simplified.gpkg") +# Generate simplified versions at 10m: +oa11_simplified_10m <- st_simplify(oa11, dTolerance = 10) # 10 m +lsoa11_simplified_10m <- st_simplify(lsoa11, dTolerance = 10) # 10 m +local_authorities_simplified_10m <- st_simplify(local_authorities, dTolerance = 10) # 10 m +countries_simplified_10m <- st_simplify(countries, dTolerance = 10) # 10 m +st_write(oa11_simplified_10m, "data/infuse_oa_lyr_2011_simplified_10m.gpkg") +st_write(lsoa11_simplified_10m, "data/infuse_lsoa_lyr_2011_simplified_10m.gpkg") +st_write(local_authorities_simplified_10m, "data/infuse_dist_lyr_2011_simplified_10m.gpkg") +st_write(countries_simplified_10m, "data/infuse_ctry_2011_simplified_10m.gpkg") -# Create modest buffer around quite small building polygons for the sake of visualisation at very large scale where small polygons can appear as points -buffer <- st_buffer(buildings,150) -# Dissolve and merge overlapping shapes -union <- st_union(buffer) -# Generate a masking layer, with filled space for unoccupied layers -difference <- st_difference(countries$geom, union) +# Generate simplified versions at 100m: +oa11_simplified_100m <- st_simplify(oa11, dTolerance = 100) # 100 m +lsoa11_simplified_100m <- st_simplify(lsoa11, dTolerance = 100) # 100 m +local_authorities_simplified_100m <- st_simplify(local_authorities, dTolerance = 100) # 100 m +countries_simplified_100m <- st_simplify(countries, dTolerance = 100) # 100 m + +st_write(oa11_simplified_100m, "data/infuse_oa_lyr_2011_simplified_100m.gpkg") +st_write(lsoa11_simplified_100m, "data/infuse_lsoa_lyr_2011_simplified_100m.gpkg") +st_write(local_authorities_simplified_100m, "data/infuse_dist_lyr_2011_simplified_100m.gpkg") +st_write(countries_simplified_100m, "data/infuse_ctry_2011_simplified_100m.gpkg") + +## Initial work on data with buildings shapefile for large scale visualation ----- +# Create modest buffer around quite small building polygons for the sake of visualisation at +# very large scale where small polygons can appear as points. Initial work in QGIS confirmed that 150m +# will render coherent shapes at national zoom level after dissolving +# Use union to dissolve and merge overlapping shapes +buildings_buffer <- st_union(st_buffer(buildings,150)) # Write results to a file: -st_write(difference, "data/countries_cropped_union_buffer_150.gpkg") +st_write(buildings_buffer, "data/OS_Open_Zoomstack_district_buildings_buffered.gpkg") + +## Process countries simplified shapefiles ----- +# Generate a masking layer, based on difference between buffered buildings layer and admin shapefile +# with filled space for unoccupied layers +difference_ctry <- st_difference(countries_simplified_100m$geom, buildings_buffer) +## Write results to a file: +st_write(difference_ctry, "data/infuse_ctry_2011_simplified_100_buildings_overlay_.gpkg") +# Simplify layer +difference_ctry_simplified = st_simplify(difference_ctry, dTolerance = 100) # 100 m +st_write(difference_ctry_simplified, "data/infuse_ctry_2011_simplified_100_buildings_overlay_simplified.gpkg") # Invert polygons in this new layer -inversion <- st_difference(countries$geom, difference) +inversion_ctry <- st_difference(difference_ctry, countries_simplified_100m$geom) # Write results to a file: -st_write(inversion, "data/countries_cropped_union_buffer_150_inverted.gpkg") +st_write(inversion_ctry, "data/infuse_ctry_2011_simplified_100_buildings.gpkg") +inversion_ctry_simplified = st_simplify(inversion_ctry, dTolerance = 100) # 100 m +st_write(inversion_ctry_simplified, "data/infuse_ctry_2011_simplified_100_buildings_simplified.gpkg") + +## Process local authorities simplified shapefiles ----- +difference_la <- st_difference(local_authorities_simplified_100m$geom, buildings_buffer) +## Write results to a file: +st_write(difference_la, "data/infuse_dist_lyr_2011_simplified_100_buildings_overlay.gpkg") +# Simplify layer +difference_simplified = st_simplify(difference_la, dTolerance = 100) # 100 m +st_write(difference_simplified, "data/infuse_dist_lyr_2011_simplified_100_buildings_overlay_simplified.gpkg") +# Invert polygons in this new layer +inversion_la <- st_difference(difference_la, local_authorities_simplified_100m$geom) +# Write results to a file: +st_write(inversion_la, "data/infuse_dist_lyr_2011_simplified_100_buildings.gpkg") +inversion_simplified_la = st_simplify(inversion_la, dTolerance = 100) # 100 m +st_write(inversion_simplified_la, "data/infuse_dist_lyr_2011_simplified_100_buildings_simplified.gpkg") + +## Process countries shapefile ----- +difference_ctry <- st_difference(countries$geom, buildings_buffer) +# Write results to a file: +st_write(difference_ctry, "data/infuse_ctry_2011_buildings_overlay.gpkg") +# Invert polygons in this new layer +inversion <- st_difference(difference_ctry, countries$geom) +# Write results to a file: +st_write(inversion, "data/infuse_ctry_2011_buildings.gpkg") # Create simplified version: -inversion_simplified = st_simplify(inversion, dTolerance = 150) # 2000 m -st_write(inversion_simplified, "data/countries_cropped_union_buffer_150_inverted_simplified.gpkg") +inversion_simplified = st_simplify(inversion, dTolerance = 100) # 100 m +st_write(inversion_simplified, "data/infuse_ctry_2011_buildings_simplified.gpkg") + +## Process local authorities shapefile ----- +difference_la <- st_difference(local_authorities$geom, buildings_buffer) +# Write results to a file: +st_write(difference_la, "data/infuse_dist_lyr_2011_buildings_overlay.gpkg") +# Invert polygons in this new layer +inversion_la <- st_difference(difference_la, local_authorities$geom) +# Write results to a file: +st_write(inversion_la, "data/infuse_dist_lyr_2011_buildings.gpkg") \ No newline at end of file