[GRASS5] zoom and pan in v.digit (was raster map file format)

[Michael Barton]

Given what you've said, I don't see any way of realistically getting around
the issue of background zoom either, given the tools at hand.

I guess trying to deal with the reported crashes (I haven't had problems but
haven't used it much) and the need to restart a line when panning/zooming
(this is important) are bigger priorities.

Michael
__________________________________________
Michael Barton, Professor of Anthropology
School of Human Evolution and Social Change
Arizona State University
Tempe, AZ 85287-2402

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



> From: Glynn Clements <glynn at gclements.plus.com>
> Date: Mon, 07 Nov 2005 21:11:23 +0000
> To: Michael Barton <michael.barton at asu.edu>
> Cc: <grass5 at grass.itc.it>
> Subject: Re: [GRASS5] zoom and pan in v.digit (was raster map file format)
> 
> 
> Michael Barton wrote:
> 
>> I'd like to add, a bit different from what Maciek suggests, that any zooming
>> OR panning in v.digit should stay in v.digit and have no effect on the
>> region for display or analysis outside of v.digit.
> 
> v.digit does this so that any external commands which it invokes use
> the same region settings as v.digit.
> 
> AFAICT, there are two cases, both in display.c:
> 
> 1. display_bg() executes a sequence of user-specified commands to draw
> the background.
> 
> 2. display_erase() executes d.erase to erase the background.
> 
> The second is gratuitous; it should just erase the background itself.
> 
> However, there's no getting around the former; the only way to make an
> external command use a specific region is to modify the WIND file.
> 
> One option is to save the WIND file prior to executing the commands
> then restore them afterwards.
> 
> Another option would be to modify G_get_window() so that you can force
> it to read a different file by using an environment variable. Then,
> v.digit could write the modified region to a temporary file and force
> the background commands to use that via the environment variable.
> 
> In either case, the auto-redraw feature won't work, as the commands
> will get the normal region rather than v.digit's internal version.
> 
> -- 
> Glynn Clements <glynn at gclements.plus.com>