pack/unpack rle

[mdsumner]

Internal functions pack_raster and unpack_raster.

Only suitable for polygon seas.

## classic fasterize

library(fasterize)
library(raster)
library(stars)
library(dplyr)

nr <- 360
nc <- 720
r0 <- raster(extent(-180, 180, -90, 90), nrows = nr, ncols = nc, crs = "+init=epsg:4326")
pols <- rnaturalearth::ne_countries(returnclass = "sf")
pols$row_index <- as.integer(seq_len(nrow(pols)))
## fudge this happy future day of cell abstraction
dummy <- fasterize(pols, r0, field = "row_index")

index <- pack_raster(dummy)
plot(unpack_raster(r0, index))

pryr::object_size(dummy)
pryr::object_size(index)

was started at rgdal-dev/rasterwise#9

[mdsumner]

see hypertidy/controlledburn