R Levelplot overlaying two SpatialPolygonsDataFrame on a RasterLayer projection

Question

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I'm having some trouble plotting a RasterLayer and a SpatialPolygonsDataFrame in a level plot in R. Something is wrong with the projection, but I don't understand what.

Here you can find my reproducible example data and code:

library(sp)
library(rgdal)
library(rgeos)
library(raster)
library(rasterVis)
library(maptools)

setwd("C:/...path_to/test2")
data<-read.csv("test.csv", header=TRUE)

#creating the raster from a data.frame and giving projection
raster<-rasterFromXYZ(data, crs="+proj=longlat")
raster_proj<-projectRaster(raster, crs="+proj=longlat +datum=WGS84 
+ellps=WGS84 +towgs84=0,0,0,0,0,0,0 +no_defs")

#loading shapes
nuts<-readShapePoly("NUTS_RG_WGS84.shp", proj4string=CRS("+proj=longlat"))
countries<-readShapePoly("countries.shp", proj4string=CRS("+proj=longlat"))

#subsetting the raster
raster_clip<- crop(raster_proj, countries, snap="near")

#plot
p.strip <- list(cex=1.5, lines=1, fontface='bold') 
x.scale <- list(cex=1.5)
y.scale <- list(cex=1.5)
label <- list(labels=list(width=1, cex=1.5), height=0.95)
levelplot(raster_clip, par.settings = RdBuTheme, margin=FALSE,
      at=seq(min(na.omit(values(raster_clip))), max(na.omit(values(raster_clip))), length.out=15),scales=list(x=x.scale, y=y.scale), 
      par.strip.text=p.strip, colorkey=label, xlab=list(label="Longitude", cex=2), ylab=list(label="Latitude", cex=2))+ 
layer(sp.polygons(nuts))+layer(sp.polygons(countries))

The error message is:

Error: Attempted to create layer with no geom.

But the raster and the polygons are in the same projection. I also tried to re-project the polygons using:

nuts <- spTransform(nuts, CRS("+proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0,0,0,0,0 +no_defs"))
countries <- spTransform(countries, CRS("+proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0,0,0,0,0 +no_defs"))

Any Idea?

Answer 1

If you don't want to or can't detach ggplot2 because you need it for something else, you can also call the layer function specifically from the latticeExtra package using:

levelplot(myRaster) + 
  latticeExtra::layer(sp.polygon(myPolygon))