[R-sig-Geo] color category SpatialGridDataFrame SpatialPolygonsDataFrame Corine Land Cover Global Land Cover 2000

[Patrick Giraudoux]

Dear all,

I am wondering what is the safest way to handle colors when 
SpatialGridDataFrame data are categories. spplot() or image() are 
extremely convenient when attributes are continuous variables or so (eg 
altitude, rainfall, etc...), but the colorRamp() system and the 
col.regions, col arguments, though extremely powerful in other cases, is 
not really adapted to category data such as Corine LandCover or Global 
Land Cover 2000 codes. Thus to link pixels to the right color may be 
quite tedious (however I may have missed something...).

One option I though about was to change raster into shapefile (or 
SpatialGrid into SpatialPolygons objects), but again the straight way to 
get right colors is not evident.

Any idea ?

Patrick