[GRASS-dev] Request to add a GCP file in vector directories

[Michael Barton]

> From: Glynn Clements <glynn at gclements.plus.com>
> Date: Wed, 7 Jun 2006 07:33:32 +0100
> To: Michael Barton <michael.barton at asu.edu>
> Cc: grass5 <grass-dev at grass.itc.it>
> Subject: Re: [GRASS-dev] Request to add a GCP file in vector directories
> 
> Unlike i.rectify, v.transform doesn't operate upon maps from a
> different location. You have to get the source map into the current
> location first.

True. I.target can also be set to the current location/mapset. For
consistency, the georectifier can operate on maps (raster and vector) from
other locations and the same location (I'm adding this part now).

> 
> [On the last point, g.copy should probably have an option to allow
> data to be copied from different locations or even from different
> database directories.]

This would be nice as long it wasn't misused (e.g., copying a raster from a
latlon location to a utm location)
> 
> Also, transformations are arguably a property of a location rather
> than a specific map. If you had a number of maps, all in the same
> (unspecified) coordinate system, you would probably want to use the
> same transformation for all of them.

This is a good point. Should a generic gcp file just be stored in PERMANENT?
What about maps with different extents--especially non-overlapping maps--in
the same location?

Michael


__________________________________________
Michael Barton, Professor of Anthropology
School of Human Evolution & Social Change
Center for Social Dynamics & Complexity
Arizona State University

phone: 480-965-6213
fax: 480-965-7671
www: http://www.public.asu.edu/~cmbarton