I have found similar questions, but most use different packages.
I have a shapefile with 20 multipolygons, with a few attributes. All I want is to create a raster whereby each raster cell's value is the count of the polygons that overlap with that cell.
library(sf)
library(raster)
shapefile <- st_read("x.shp")
# Create a raster template with the desired resolution (e.g., 5 square kilometers)
res <- 5000
raster_template <- raster(ext = extent(shapefile), res = res)
# Convert the shapefile to the same CRS as the raster template
shapefile <- st_transform(shapefile, crs(raster_template))
# Create a raster with the number of overlapping polygons in each cell
overlap <- rasterize(shapefile, raster_template, field = 1, fun = "count")
Alternatively, because 'field 1' is the Object ID, I've created an attribute that is consistently '1' for each feature. This is now field 5. So I've edited the code :
richness <- rasterize(shapefile, raster_template, field = 5, sum = "TRUE")
or
richness <- rasterize(shapefile, raster_template, field = 5, fun = sum)
However, all attempts return an empty raster.
Some additional info on the objects:
