Re: Spreadsheet display mode

["David O'Toole" <dto@gnu.org>]

Hi Richard,

I wrote something called "cell-mode" that seems similar to what you
describe. It holds a grid of cells whose "labels" are
application-defined strings with text properties, and draws them to a
buffer. The display code can do several things:

  - Insert display-property "specified spaces" during rendering so
that all cells in a column
    are the same width---even when there are images and text in the label
  - optional vertical and/or horizontal "zebra stripes" (i.e. every
other column / row is tinted)
  - seamlessly tile various identically-sized rectangular images

I did have a version that supported embedding an interactive
spreadsheet UI into random buffers as a minor mode, using display
properties. You can't put point inside the text, but it can still
receive mouse clicks and keyboard events, so I could just draw a fake
cursor (with an overlay) and map keystrokes to commands that move the
fake cursor.  The illusion was pretty good.

Anyway, I'm trying to make it into a very general-purpose library that
could be used as a front-end for SES and all the other "display stuff
in a table interactively" modes (dired, buffer list, etc)

Here are some screenshots:

an old demo with some interactive objects:
http://dto.freeshell.org/images/cell-mode.png

a recent shot of a rudimentary XPM pixel art drawing program:
http://dto.freeshell.org/images/pixel-preview.png

an example of embedding cell-mode in a buffer:
http://dto.freeshell.org/images/EcaSpace-alpha.png

image tiling stuff:
http://dto.freeshell.org/images/RogueLike-11.png
http://dto.freeshell.org/images/RogueLike-12.png

larger images:
http://dto.freeshell.org/images/cell-mode-2.png

I've been looking for an excuse to work on cell-mode again. It does
need some fixes (especially to make it work well on ttys) but if
anyone is interested i will clean it up and post it to
gnu.emacs.sources.
------------------------------------

From: Richard Stallman <rms <at> gnu.org>
Subject: Spreadsheet display mode
Newsgroups: gmane.emacs.devel
Date: 2007-11-22 16:23:02 GMT (8 hours and 5 minutes ago)

Someone suggested that Emacs should have a spreadsheet display mode.
I did some thinking about the idea.  A list of cell definitions could
control how to display each line, and they could go in a `display'
property that might be on an overlay or text property (so that you
could display just a part of the buffer as a spreadsheet).

The actual text would use delimiters to separate cell contents.
The cell definitions could specify what delimiters to use.

What do you think?