donuts - Vector format flaw!(?)

GRASS GRASS user
1

Allan Axon writes:

Using 4.0,
one problem I have encountered in going from vector to raster is handling
"donuts" of category 0:

             ____________
            | _____ |
            | |__0__| 1 |
            |____________|

When rasterized, the above situation, gives

            1111111111111 11111111111
            1111111111111 not 11100000111
            1111111111111 11111111111

There are ways to work around this, but vector maps still have to be
examined in order to recognize the presence of similar conditions.

Has this problem already been addressed in 4.1?

Did you run v.support before doing the v.to.rast conversion? Granted, I'm
using 4.1, but these are the results I get:

     __________
    | _____ |
    | |__0__| 1|
    |__________|

gives me

  111111111
  110000111
  111111111

*as long as* the attribute point is within the "1" area, not the "0" area. If
the attribute point is within the "0" area, even though I select the outer
polygon as the area boundary, I get:

  000000000
  001111000
  000000000 !!!

This seems pretty reasonable to me, if not terribly convenient!

--
Malcolm D. Williamson - Research Assistant E-mail: malcolm@cast.uark.edu
Center for Advanced Spatial Technologies Telephone: (501) 575-6159
Ozark Rm. 12 Fax: (501) 575-3846
University of Arkansas
Fayetteville, AR 72701