[GRASS-user] v.centroids question

[John C. Tull]

I have a road network where I want to convert the road lines into  
boundaries, then turn the resulting spaces inside of roads into areas.  
Converting the roads to boundaries was no problem using v.type and  
v.clean tool=snap, but getting centroids into the polygons is  
trickier. Apparently, v.centroids will not add centroids to areas  
where there are boundaries that terminate inside a polygon (i.e., dead- 
end roads inside what I am hoping to turn into an area), so I end up  
with far fewer areas than I want. Do boundaries have to be contiguous  
without dangles (is that the right use of the terminology?)?

Is there a way to get centroids into areas such as these where the  
road dangles are ignored? I don't want to drop those dead-end roads  
because they are informative, but I guess I may have to do so and then  
use v.overlay or similar at a later stage. There are also too many  
potential areas to try and manually add the centroids with v.digit.  
Perhaps there is a means in v.edit unknown to me. Any ideas or  
suggestions would be greatly appreciated. I am using GRASS 6.3rc5.

Thanks,
John Tull