[GRASS-dev] Re: [GRASS GIS] #106: wxgrass: zoom to computational region does not respect resolution set with g.region

[Michael Barton]

On Mar 28, 2008, at 5:32 AM, Moritz Lennert wrote:
> On 28/03/08 07:10, Michael Barton wrote:
>>>
>>>  I think it would be useful to have the same system as in gis.m,  
>>> i.e. with
>>>  one display mode aligning to window size and another mode  
>>> showing the
>>>  exact computation region, i.e. respecting extent and resolution.
>> I think that these two different modes are fairly confusing to  
>> most users.
>> Martin has implemented something that I think is much more useful  
>> and easier to understand, and that serves the same purpose. As  
>> mentioned above, the display always fills the window and has a  
>> constant resolution. However, the computational region is shown by  
>> a red box outline. This means you can always tell the region in  
>> which map modification operations will take place, without having  
>> a very strange-looking map in the display window, with a lot of  
>> white space around it.
>
> But that brings us back to my original response ("The issue is not  
> only the extent, but also the resolution."). Yes, the red box is  
> very useful (although the functionality is maybe a hidden - maybe  
> the "show" text box should always be visible and read "show extent  
> of computational region", but a visual information about the  
> resolution is also very important. It has happened to me often  
> enought that I launch a command which then takes much longer than  
> expected, only to find out that the computational region's  
> resolution was much higher than the display's. Having a mode which  
> allows seeing the exact computational region settings is, thus,  
> very helpful...No need to make it the default, and you could  
> possibly hide it a bit to not confuse users, but IMHO, it should be  
> an option for power users.
>
> Moritz

Moritz,

I agree that it would be quite helpful for just the reason you  
describe to have the computational resolution shown, if it's not (it  
may be an option, but I don't remember at the moment). This is a good  
idea to add that to the display option.

But there is no point in making the display itself have the same  
resolution (xy pixels) as the map.

Michael