[GRASS5] g51 v.build accelerated

[Radim Blazek]

v.build accelerated now:

grass50  grass51
270s     9s     (with attributes)
124s     6s     (without attributes)

How boring. Somebody should check, seems to be too good. 

Vector with attributes:
Number of nodes     :   50201
Number of primitives:   50200
Number of points    :   10000
Number of lines     :   10000
Number of boundaries:   20200
Number of centroids :   10000
Number of areas     :   10000
Number of isles     :   1

Vector without attributes:
Number of nodes     :   40201
Number of primitives:   40200
Number of points    :   10000
Number of lines     :   10000
Number of boundaries:   20200
Number of centroids :   0
Number of areas     :   10000
Number of isles     :   1

Note: It is slower for isolated areas. Even for isolated areas it could be 
improved by searching for nodes of islands in area box, but in final
version (which should have spatial index), will be searching for areas better
because number of isles is usually less than number of areas. Just note -
you can forget it.


Radim
Praga, Bohemia