[GRASS-dev] Re: [GRASS-user] GRASS 7 vector topology format changed

[Hamish]

Markus Metz wrote:
> the GRASS 7 vector topology format changed a bit. I have
> removed redundant information (bounding boxes) from vector
> topology

Hi,

just wondering how redundant that is.. for point data completely,
but for a polygon of 500,000 vertices (forest boundary or the
coastline of Florida) knowing the bbox before you touch the data
array can be a huge speed up. Many of PostGIS's fns work that
way IIRC.

so are per-feature bounding boxes completely gone? or just some
double-storing of them, or redundant data stored within them?

are small vectors (ie points) sped up at the cost of worse
performance of scattered large non-point datasets?

is time to run d.vect in a sub-region of the overall map a good
way to test the performance difference?


(hoping this means we can have the best of both worlds!)

thanks,
Hamish