convert raster objects or raster readable files to .kml overlay files

rasterToKML.r

rasterToKML <- function(x, out='Rgrid', png=FALSE, name=out, proj="+proj=longlat") {
  require(raster)
  require(maptools)
  require(rgdal)
  require(rgeos)
  x <- raster(x)
  SG <- as(x, 'SpatialGridDataFrame')
  proj4string(SG) <- CRS(proj)
  SG <- GE_SpatialGrid(SG)
  if(png) png <- sprintf('%s.png', out) else png <- tempfile()
  png(file=png, width=SG$width, height=SG$height, bg="transparent")
    par(mar=rep(0, 4), xaxs="i", yaxs="i")
    plot.new()
    plot.window(xlim=SG$xlim, ylim=SG$ylim)
    plot(x, legend=FALSE, add=TRUE)
  dev.off()
  invisible(capture.output(kmlOverlay(SG, sprintf('%s.kml', out), png, name)))
    if(file.exists(sprintf('%s.kml', out))) cat('KML file created') 
      else cat (':( Sorry. Something went horribly wrong')
}