[GRASS5] New raster formats

[Glynn Clements]

Trevor Wiens wrote:

> I've noted that there has been talk of a new raster format for future
> versions of GRASS. What kind of changes are being considered?

Tiled storage (as an alternative to rows), more flexible support for
maps with a small number of categories, fixed-point maps, built-in
caching (eliminating the need for the segment and rowio libraries).

> One
> thing I miss from SPANS was the quadtree format which allowed for very
> quick processing of data without loss of spatial resolution. I realize
> that implementing this in GRASS would mean rewrites to much of the
> existing code to deal with the complexities of the format but I
> thought it would be worth throwing out the idea for consideration, as
> it seems that we constantly face bigger and bigger data sets as
> computing power grows. Since PCI's takeover of SPANS, they've dropped
> this and there is no commercial vendor willing to put in the effort to
> gain the benefits from the use of this format (speed and disk space). 
> I'm curious if this has been considered.

It isn't amongst the features which I've considered for a new raster
format. Unfortunately, I suspect that it would probably make writing
modules too complex.

-- 
Glynn Clements <glynn at gclements.plus.com>