[GRASS-dev] d.vect render= and corrupted vector display

Maciej Sieczka tutey at o2.pl
Mon Apr 9 11:30:46 EDT 2007

Glynn Clements wrote:
> Maciej Sieczka wrote:

>> By "boundary case", do you mean to assume that v.in.region+d.vect is
>> unlikely to be used? Just curios.

> No, I mean that it's a case where a "point" is neither inside nor
> outside but on the boundary.
> The term doesn't refer solely to geometry. In any context where some
> continuous (non-discrete) space is partitioned into distinct
> categories, you get values which fall on the boundary between
> categories. E.g. if you partition the real numbers into positive and
> negative, which is zero?

As to display, I guess I get it know. However, I'm not sure what to
think about this issue in regard to computational GRASS region.

Let's take a following eaxample; in spearfish:

$ g.region rast=landuse -a
$ v.in.region lu_border type=line
$ v.category lu_border out=lu_border_cat option=add
$ g.region vect=lu_border_cat
$ v.to.rast input=lu_border_cat output=lu_border_cat use=cat

The outcome is a raster which includes only the top and left lines,
while region was ordered to cover the whole "lu_border_cat" vector.
>From user's point of view, half of the input vector was ignored by
v.to.rast, in error. Is this not fixable too?


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