TCL/TK and GRASS

[Mark P. Line]

On Thu, 3 Mar 1994, Peter Mikes wrote:

>  | Mark P. Line   of Open Pathways wrote :
> 
>  |  Most importantly, I think we need to ascertain what kinds of GUI
>  |  styles/paradigms are in greatest demand. Personally, I favor the
>  |  drag-and-drop/popup-menu object-oriented style, which would lend itself to
>  |  a lot of GRASS. Others might favor a more sttraightforward orientation
>  around the GRASS command-line interface. Then there is the functional
>  |  dataflow style as found in Khoros and AVS, which would be the most elegant
>  |  means of encapsulating the current philosophy of GRASS in a GUI, perhaps,
>  |  but also the most work to develop.
> 
>    I would like to second this - both the need to dicuss what style,
>           and the motion to consider Khoros.
>  I am new to Grass but I have used Khoros to build GUI for other (non) Khoros
>   modules and it seems that to me so far that Khoros and Grass would be a natural marriage.
> 
>  Unlike AVS, Khoros  is free and source is available and it was even ported to Linux.
> 
>  Khoros looks formidable (to the deloper, not to the  user) on the first glance, and there
>  certainly is a learning curve there, but it is not realy that hard to use it as GUI tool.
> 
>       ( Basically, any module which has proper CLUI, a CLUI conforming to Khoros standard,
>   can be plugged into Cantata in matter of ninutes; CLUI is Khoros jargon for Command Line
>   User Interface (i.e. command line arguments) and Cantata is Khoros's X-application with
>   pull down menus and canavas. Once the module is 'plugged in',  it can be called by means
>   of menu and different modules can be inter-connected... )

My concern with Cantata would be its flexibility. I don't currently have
the 80MB to spare on my GRASS box I would need to take a look at Khoros
directly. Even if we could plug in the GRASS main/alpha/contrib commands
and even the related stuff into Cantata, maybe users would find the user
interface somehow lacking in certain respects. If that were the case, then
modification of Cantata itself might be more trouble than it was worth.

I think there is still something to be said for starting the GRASS GUI
from scratch, as it were, using something like Tcl/Tk -- that way, we
would have all the flexibility we could ever want, and it seems that a
Tcl/Tk implementation of a Khoros/AVS-like dataflow paradigm might not be
all that involved after all. In fact, I wouldn't be surprised if it's
already been done. I'll check through the Internet in the next couple of
days, but maybe one of you already knows of something. 

>   Two issues merit consideration:
>  1) Khoros2 is supposed to be released this August ( beta version is available now
>             to memebers of consortium). Questiom is: If we choose Khoros - should we wait for 2?

I'm interested in starting work on a GRASS GUI ... Real Soon Now.

>   2) While whole of Khoros is more complex then Tcl/Tk, it also offers more, things
>      such as interoperability across platform and co-authorong tools (such as Concert),
>      and demo-(click capture) capabilities, which may be very useful.
>      BTW: Khoros 1  has rudimentary GIS, which I heard is enhanced  in version 2; may be not only
>      Grass needs Khoros but also: Khoross needs Grass. Good marriages should work like this.

I agree that the integration of GRASS and Khoros would be a match made in
geostationary orbit, but I also think we need to take a good hard look at
what GRASS would look like under Cantata and what sorts of straitjackets
we'd be letting ourselves in for.

-- Mark

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Mark P. Line                       Phone: +1-206-733-6040
Open Pathways                        Fax: +1-206-733-6040
P.O. Box F                         Email: markline at henson.cc.wwu.edu
Bellingham, WA 98227-0296
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