rasterize using the extent of an object and no raster

rasterize_extra.r

library("raster")

setMethod("rasterize", signature(x="data.frame", y="missing"), 
          function(x, field, res = 1, fun = 'last', ...) {
            r = raster(res = res, xmn = min(x$x), xmx = max(x$x), ymn = min(x$y), ymx = max(x$y))
            rasterize(x, r, field = field, fun = fun, ...)
          })

setMethod("rasterize", signature(x="SpatialPoints", y="missing"), 
          function(x, field, res = 1, fun = 'last', ...) {
            box = sp::bbox(x)
            r = raster(res = res, 
                       xmn = box[1, "min"], 
                       xmx = box[1, "max"], 
                       ymn = box[2, "min"], 
                       ymx = box[2, "max"])
            rasterize(x, r, field = field, fun = fun, ...)
          })

setMethod("rasterize", signature(x="SpatialLines", y="missing"), 
          function(x, field, res = 1, fun = 'last', ...) {
            box = sp::bbox(x)
            r = raster(res = res, 
                       xmn = box[1, "min"], 
                       xmx = box[1, "max"], 
                       ymn = box[2, "min"], 
                       ymx = box[2, "max"])
            rasterize(x, r, field = field, fun = fun, ...)
          })

setMethod("rasterize", signature(x="SpatialPolygons", y="missing"), 
          function(x, field, res = 1, fun = 'last', ...) {
            box = bbox(x)
            r = raster(res = res, 
                       xmn = box[1, "min"], 
                       xmx = box[1, "max"], 
                       ymn = box[2, "min"], 
                       ymx = box[2, "max"])
            rasterize(x, r, field = field, fun = fun, ...)
          })

setMethod("rasterize", signature(x="sf", y="missing"),
          function(x, field, res = 1, fun = 'last', ...) {
            box = st_bbox(x)
            r = raster(res = res,
                       xmn = box["xmin"],
                       xmx = box["xmax"],
                       ymn = box["ymin"],
                       ymx = box["ymax"])
            rasterize(x, r, field = field, fun = fun, ...)
          })

setMethod("rasterize", signature(x="sf", y="RasterLayer"),
          function(x, y, field, res = 1, fun = 'last', ...) {
            rasterize(as(x, "Spatial"), y, field = field, fun = fun, ...)
          })

setMethod("rasterize", signature(x="sf", y="RasterStack"),
          function(x, y, field, res = 1, fun = 'last', ...) {
            rasterize(as(x, "Spatial"), y, field = field, fun = fun, ...)
          })

setMethod("rasterize", signature(x="sf", y="RasterBrick"),
          function(x, y, field, res = 1, fun = 'last', ...) {
            rasterize(as(x, "Spatial"), y, field = field, fun = fun, ...)
          })

round_to <- function(x, to = 1, origin = 0, up = TRUE) {
  if(up) ceiling((x + origin) / to) * to + origin
  else floor((x - origin) / to) * to + origin
}

#' Utility function to round to a resolution and shift according to an origin
round_to <- function(x, to = 1, origin = 0, up = TRUE) {
  if(up) ceiling((x + origin) / to) * to + origin
  else floor((x - origin) / to) * to + origin
}

#' Rasterize on a rounded grid
#' 
#' Rasterizing on a rounded grid with defined origin facilitates future merging and stacking of data
rasterize_round <- function(x, field, res = 1, fun = 'last', round = TRUE, origin = c(0, 0), ...) {
            origin = rep(origin, 2)[1:2]
            box = st_bbox(x)
            r = raster(res = res,
                       xmn = round_to(box["xmin"], res, origin[1], up = FALSE),
                       xmx = round_to(box["xmax"], res, origin[1], up = TRUE),
                       ymn = round_to(box["ymin"], res, origin[2], up = FALSE),
                       ymx = round_to(box["ymax"], res, origin[2], up = TRUE))
            rasterize(x, r, field = field, fun = fun, ...)
}

if (FALSE) {
  testthat::expect_equal(round_to(101.1, 10, 0), 110)
  testthat::expect_equal(round_to(101.1, 10, 1), 111)
  testthat::expect_equal(round_to( 99,   10, 1), 101)
  testthat::expect_equal(round_to(101.1, 10, 0, up = FALSE), 100)
  testthat::expect_equal(round_to(101.1, 10, 1, up = FALSE), 101)
  testthat::expect_equal(round_to(99, 10, 1, up = FALSE), 91)
}