Re: Guppi 0.0.1

[Havoc Pennington <rhpennin midway uchicago edu>]

On Fri, 21 Aug 1998, Miguel de Icaza wrote:
> 
> Wow!  I loved the Guppi screenshot!
>

It included just about every piece of existing functionality though, so
don't get too excited. :-)  (there is some invisible infrastructure, and
the plot library can do more but has no GUI.)
 
> I am now in the process of downloading the new libraries.  Any chance
> we can put the Gtk--Draw stuff on the CVS?  
> 
> (I want to look at it asap, to consider a possible corba-ization to
> make it work as the plotting engine of Gnumeric).
> 

On the Gtk-- list there is some talk about adding the draw portions to
Gtk--; the plot stuff would then be in a standalone library. I imagine it
could be CVSd. 

I think that may be the wrong abstraction layer for CORBA though; the plot
library is just a bunch of primitives that operate on any drawable
(wrapped with a Gdk_Draw object). For example, "draw an axis with tick
marks,"  "draw a cross/circle/dot marker," "label the axis with round
numbers." It could be enhanced (and will be, the functionality isn't
complete by any means).

My idea for what to CORBA-fy was 1) a column/row of data and operations on
it, including date/money/real number typing and formatting and 2) a bunch
of "plot modules," including the stuff to set up a plot type and the
actual plot (the edit and display windows in Guppi). A plot module would
operate on CORBA data set objects. It seems to me that Guppi and Gnumeric
could both use that interface, if done correctly. Guppi would be a bunch
of objects and some glue, Gnumeric a touch more complex. :-) 

Oh, also it would be nice to share some of the text import code. 

But I don't know too much about CORBA and I definitely don't know what
Gnumeric would need. Plus I haven't thought about it all that much.

For Guppi the big job is to write the different plot modules (price bars,
scatter plot, histogram, pie chart, etc.) - once I have two working it
should begin to become clear how things will work, what they have in
common and what their interface is. First there are a couple fixes to what
exists - I was going to fix the text import (moving it into libgoose and
changing it around), and redo the scatter plot display with a GnomeCanvas
or GtkFixed or something other than the lame GtkTable hack it uses now,
which prevents proper layout. Then start on a second type of plot. 

I'm very interested in talking about how everything will work and how to
do the design, since there have been only two of us looking at the code so
far, and we are CORBA-clueless. I'm unhappy with a lot of things but
others are pretty neat. 

Havoc