I have created a SpatialPoints object, converted it to a ppp object, and then run spatialstat's density function create a density object. I can use the png function to make a density plot. I would like the density plot to be transparent so that I can include it as a layer on a map. Is there any way to create a partially transparent density plot that will be suitable for a map overlay?
> class(ppp) # a ppp object created from a SpatialPoints object [1] "ppp" > png("tmp.png", width=SGqk$width, height=SGqk$height, bg="transparent") > d<-density(ppp,1),col=rainbow(4)) > plot(d) > dev.off() # problem is that tmp.png has a solid background color that obscures the map when I try to use it as a map overlay [[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