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Re: spreadsheets & clim

>Date: Wed, 16 Mar 1994 19:50-0500
>From: Jim Aragones <aragones@crd.ge.com>
>Subject: spreadsheets & clim
>
>i've been thinking about implementing some of the functionality of a
>spreadsheet using clim and was wondering if anyone had been moderately
>successful.  my simple approach was to use incremental redisplay to
>accept values in a table.  i've had a very little success - in other
>words, what i have does what i need, but it's too slow and has lots of
>nasty quirks.

I have a spreadsheet/table-editing system that I've been working on for
some time[*].  My experience is much the same as yours, i.e. that the
"normal" types of redisplay are too slow by an order of magnitude to be
useful on all but the most trivial tables.

  [* The original version was written in an early CLIM-0.9.]

For example one application used the system to display tables that were
typically on the order of 30 columns by 600-1000 rows.  Doing this in the
naive, straightfoward way (e.g. formatting-table + incremental redisplay)
it would take fully a couple of minutes to initially draw the complete
table and on the order of a full minute to do each incremental update.

As a result I've built a number of tools to support this work: 

1] Panes that are clever about displaying _only_ those cells that are
actually on the screen.  Furthermore there is a win in that --because the
rectangular, grid-like nature of the cells-- I don't have to worry about
output-records overlapping and the consequent problems for refresh.  (I
understand Scott McKay has a special output-record that handles some of the
grid-like issues, but I've not had a chance to look at it.)

2] A "hierarchial" pane-type that allows me to cluster a set of panes
together as a unit (sort of like the SMBX notion of using a frame as a pane
which is itself imbedded inside a frame from the good old days).

3] Some hacks to support multiple, parallel scrolling of several panes in
synchony. 

>if you know of anything that might help me, even a commercial clim-based
>spreadsheet tool, let me know.

My _hope_ is to put at least some of this in the CLIM-library.  This
depends on 1] getting my employer's blessing to do this (which I suspect
won't be much of a problem) and 2] my finding the time to actually do it.

>-jim aragones

Nichael
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