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Re: Accessible chart and diagrams -- declarative topology (was SVG 2 review request)

From: Rich Morin <rdm@cfcl.com>
Date: Wed, 17 Aug 2016 19:33:47 -0700
Cc: w3c-wai-ig@w3.org, www-svg <www-svg@w3.org>
Message-Id: <EE923727-50B8-42ED-A163-856B089D3705@cfcl.com>
To: David Dailey <ddailey@zoominternet.net>
> On Aug 17, 2016, at 10:35, David Dailey <ddailey@zoominternet.net> wrote:
> ... there has been some discussion (there really has, I'm not making this
> up!) here for several years about SVG "connectors"[1] that would have some
> graph theoretic properties. I think it is safe to say that it won't be a
> part of SVG2. On the other hand, there did seem to be some support and
> there was a good deal of discussion, since I was even present for some of it.

I'm not at all surprised to find that I wasn't the first person to have these
sorts of ideas, but I would also have had no easy way to find the best work.
Many thanks (to everyone) for the feedback, pointers, etc!

> I would hope that SVG2's approval moves along fairly smoothly ...

What he said.

> SVG 2 seems (to this "outsider") to have been a period of hunkering down ...

I think I understand your point.  However, I need to familiarize myself with
the basics of the proposed changes before criticizing anything in them.  The
specific details of SVG 2 are waaaaaaay beyond my competence (or interest,
really, except in specific cases) as a practicing programmer.

> SVG's inability to deal with connectivity (in maps, diagrams, traffic flow
> and topological constructs) has been the subject of many presentations ...

I can tell that I have even more reading to do. :)

> I've been working on a "theory of flow and drawing" that depicts such
> things as weave, underpasses, relationships, knots, visual paradox, and
> directionality; things that are currently difficult to accomplish with SVG.
> I have quite a corpus of material I've developed toward that end and am
> hoping to have it in some sort of presentable state by November.  I'm
> encouraged by the existence of concise notations for certain combinatorial
> structures like Venn diagrams, knots, tangles, and polyominoes. I think a
> declarative notation, such as you've advanced, can be brought to bear on
> problems that are fundamentally more topological and graph theoretic than
> strictly 2D and geometric. The level of abstraction and semantics would be
> higher.

  "It was my understanding that there would be no math."
  From the Saturday Night Live sketch, "Presidential Debate" in 1976.
  (Chevy Chase played Gerald Ford).

Seriously, heavily theoretical approaches can present a steep learning curve,
so I hope you can make this stuff accessible to mathematically challenged
folks like me.  I'll also note that mathematical notation itself can be quite
a challenge to blind readers.  Some can make use of encodings such as Nemeth
Braille or LaTeX; others may simply give up on this sort of material.

> I don't know if the W3C or the SVG WG is able to entertain such development
> of "declarative topology" or not. 

The IETF famously gets by on "rough concensus and running code":


If proof of concept examples exist or can be created, along with a supporting
theory, that might convince some.  Meanwhile, propose a _de facto_ standard.


http://www.cfcl.com/rdm           Rich Morin           rdm@cfcl.com
http://www.cfcl.com/rdm/resume    San Bruno, CA, USA   +1 650-873-7841

Software system design, development, and documentation
Received on Thursday, 18 August 2016 02:34:20 UTC

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