If I set the GRASS_WIDTH and GRASS_HEIGHT environment variables to
numbers (e.g., 2000 X 4000) that exceed the dimensions of my screen,
I do not actually seem to get a higher resolution postscript file
when I use ps.map to print D_cell. This can be seen most clearly when
displaying a legend with category names. The sharpest postscript output
comes from setting the environment variables at or near screen resolution.
For example, it appears that the CELL driver may take 2 rows of pixels
displayed at screen resolution (e.g., 900 rows high) and spread them
out over 4 rows in the resulting D_cell map if GRASS_HEIGHT is set to
for example, 1800, filling in between the 2 rows with blank rows rather
than interpolating. The result is a fuzzier letter with GRASS_HEIGHT
at 1800 than at 900. Has anyone else noticed this?
This is not quite what I had hoped for from the CELL driver, as I think
we want to be able to print each row of a 2700 row region on a 300 d.p.i.
printer in 9" to take advantage of the higher resolution in the printer
than we can get on our screens.
Bill Baker
bakerwl@uwyo.edu