[R-sig-Geo] Marginless plot output for georegistration of output graphics

[David Forrest]

Hi All,

I'd like to make graphic files of plots with controlled pixel->coordinate 
mapping.  Ultimately, I'd like to get the graphs out into Google earth 
KML, but to to that, I need good control of the margins or framing around 
the plot.

Basically, I'm using a spatial polygons dataframe with some 
finite element (30K elements) model output.

png(file='inun.png',width=2000,height=2000,bg = "transparent")
plot(cb,xaxs='i',yaxs='i',
    xlim=bbox(cb)[1,],ylim=bbox(cb)[2,],lty=0,col=cb$inun*4)
dev.off();

but I still have an uneven margin/border around my graphic that is hard to 
correlate to the bbox.

Any hints?

Dave
-- 
  Dr. David Forrest
  drf at vims.edu                                    (804)684-7900w
  drf5n at maplepark.com                             (804)642-0662h
                                    http://maplepark.com/~drf5n/