[GRASS-dev] Re: New installation for wxPython GUI

[Michael Barton]

Moritz,

See below.

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

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


> From: Moritz Lennert <mlennert at club.worldonline.be>
> Date: Wed, 09 Aug 2006 12:14:12 +0200
> To: Yann Chemin <ychemin at gmail.com>
> Cc: Michael Barton <michael.barton at asu.edu>, Grass Developers List
> <grass-dev at grass.itc.it>
> Subject: Re: [GRASS-dev] Re: New installation for wxPython GUI
> 
> Yann Chemin wrote:
>> Works nicely on my system!
>> 
>> About "Zoom in" behaviour, i can replicate the reason why it displays
>> a blank screen.
>> 
>> 1-type d.rast elevation.dem
>> 2-click in any point of the elevation map
>> 3-becomes blank screen
> 
> Same here
> 
>> 
>> Now, here is the catch, if instead you try;
>> 1-type d.rast elevation.dem
>> 2-POINT and DRAG to create a (invisible on my computer) box in any
>> AREA of the elevation map
>> 3-map zooms in properly

The click zooming is not implemented, only box zooming (in and out). So
click zooming behavior is "undefined" (that is, who knows what will happen).
Relevant methods need to be written. Glynn had suggested using the sqr root
of 2 as a zoom factor and this seems to work well.


> 
> Same here. But the box is only invisible in zoom in, and only as long as
> I have not used zoom out. In zoom out mode, I see the box.
> 
> However, I actually see many boxes within each other which is not very
> beautiful (see http://moritz.homelinux.org/grass/gmwxp_zoomin1.png).
> Probably just a question of erasing the previous box before redrawing
> the newly sized one.

I can erase the multi-boxes but it also clears (or covers) the underlying
map. I'm not sure how to fix this yet. Maybe someone else can figure it out.

> 
> Another problem with zooming in: the displayed area does not always
> correspond to the rectangle. Compare
> http://moritz.homelinux.org/grass/gmwxp_zoomin1.png to
> http://moritz.homelinux.org/grass/gmwxp_zoomin2.png
> which is the state after the zooming defined in zoomin1.png.

This is devilishly complicated for some reason. I'm still wrestling with it
in the TclTk interface.

> 
> Mouse wheel zooming works perfectly !

That's something!

Michael

> 
> Moritz
>