[GRASS-user] clip and rotate a raster

[Glynn Clements]

G. Allegri wrote:

> Surely a stupid question, but I can't find a way to clip a raster on the
> base of the region settings and/or the base of a vector. I can MASK, I can
> reclass, but I can't clip!

r.resample will resample a map according to the current region
settings.

To clip to a vector map, convert the vector area(s) to a raster then
use it as a mask.

> Furthermore, is it possible to rotate a raster without the use of a 1st
> polynomial rectification through GCPs?

No.

You can translate and/or scale a map by changing its boundaries with
r.region, but the only tool to rotate or skew a map is i.rectify
(there isn't an r.rectify).

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