[R-sig-Geo] symbols on a map

[Susumu Tanimura]

Dear Drzyzga, Scott

> You might want to consider reading Paul Murrell's (2004) article, which
> addresses the transparency issue.

Thank you for the information. Semitransparent on a map was
successfully shown with command such as
plot(Mapobject,fg=rgb(1,0,0,0.5)).  As for pixmap, I can not come up
with idea to make symbol picture transparent.

> Also, empirical scatterplots and
> variogram clouds yield so much more information when the densities of
> overlapping data can be observed and considered.  

Since I am familiar to neither gstat nor geoR, I may be wrong but I
think a background of plotted vector object is usually transparent.
In this case, there is no problem.  The problem of pixmap is that
a rectangular background of bitmap picture covers the basemap, and
piles one another.

Thanks.

--
Susumu Tanimura
Dept. of Socio-environmental Medicine
Inst. of Tropical Medicine, Nagasaki University
TEL 095-849-7865 FAX 095-849-7867