Patrick, I have had some success with plotting sp objects on top of G maps with this function
gmap <- function(xy, maptype='terrain', ...) { require(RgoogleMaps) fun = points if (inherits(xy, 'Spatial')) { b = bbox(xy) if (inherits(xy, 'SpatialPoints')) { xy = coordinates(xy) } else { x = unlist(lapply(x...@polygons, function(i)slot(i, 'Polygons'))) x = lapply(x, function(x)slot(x, 'coords')) xy = matrix(ncol=2, nr=0) for (i in 1:length(x)) xy = rbind(xy, x[[i]], c(NA,NA)) fun = lines } } else { b = rbind(range(xy[,1], na.rm=TRUE), range(xy[,2], na.rm=TRUE)) } mykey <- ### fill in your google maps API key for http://localhost/ gm <- GetMap.bbox(key=localhostkey, lonR=b[1,], latR=b[2,], maptype=maptype) tmp <- PlotOnStaticMap(gm, lon=xy[,1], lat=xy[,2], FUN=fun, verbose=0, ... ) } a = matrix(runif(100)*100-50, ncol=2) gmap(a) library(sp) gmap(SpatialPoints(a), col='red', cex=2, pch='+') library(maptools) data(wrld_simpl) hti = wrld_simpl[wrld_simpl$ISO3=='HTI',] gmap(hti, lwd=2, col='red') Hth, Robert On Sat, Jan 16, 2010 at 5:35 PM, Patrick Crutcher <pcrutc...@gmail.com> wrote: > I have some shapefiles I want to plot over Google Maps tiles. I have > polygons, lines and point data. What's the most efficient way to do this? > One path might be to use the pkg RgoogleMaps, however, it is still unclear > to me how to do this. I assume using PlotonStaticMap with some combination > of reformatting the shapefile data. Thanks. > > P. > > [[alternative HTML version deleted]] > > _______________________________________________ > R-sig-Geo mailing list > R-sig-Geo@stat.math.ethz.ch > https://stat.ethz.ch/mailman/listinfo/r-sig-geo > _______________________________________________ R-sig-Geo mailing list R-sig-Geo@stat.math.ethz.ch https://stat.ethz.ch/mailman/listinfo/r-sig-geo