[html5] making standards-compliant charts

[Matt Bonner]

> "Graph" (etymologically) comes from a word meaning to mark or engrave. "Graph" 
> is often a synonym for "chart" nowadays, so I don't see why "graphical" implies 
> the absence of character data.

As far as I know, your etymology is correct.  But, recall the original exchange in this thread:

| > I am especially interested to hear how HTML experts view efforts to 
| > create bar or line charts in HTML/CSS.
| 
| Graphs are, well, graphical. HTML would generally be inappropriate. :-) 

| I'd recommend using SVG or PNG for static graphs, with SVG or <canvas> for 
| dynamic graphs, and providing tables for people who can't view the graphs.

> > Rendering chart text in an image means bigger, slower pages, ugly
> > zooming
> 
> With a _bitmap_ image, yes.

Right.  Sorry, in my day job we often use "render" to imply raster output.

> > and little hope for assistive technology to extract meaning.
> 
> I'm not sure that's true. OCR might actually be the simplest part of the 
> challenge of extracting meaning from a bitmap chart. (Not that typical web AT 
> uses OCR!)

Well, we tried several OCR packages on a fairly simple table not long ago,
and I think I'd stand my ground on this point.  OCR *and* extracting meaning
would be hard problems for AT on rasterized graphs.

So, my thinking remains that there's an opportunity to express most graphs and
charts using markup rather than raster images. Unless I misunderstand, it seems like
the language intended for this purpose is SVG.  If anyone sees a better approach,
by all means say so!

Finally, I forgot to thank you for this excellent point:

> It's arguably a good idea (from an accessibility and general usability
perspective) to
> explicitly and visibly state any trends shown by the
graphs too, rather than leaving
> people to try to guess at them.

thanks again,
Matt



----- Original Message ----
> From: Benjamin Hawkes-Lewis <bhawkeslewis at googlemail.com>
> To: Matt Bonner <mateubonet at yahoo.com>
> Cc: Ian Hickson <ian at hixie.ch>; Help at lists.whatwg.org
> Sent: Monday, December 29, 2008 5:05:04 PM
> Subject: Re: [html5] making standards-compliant charts
> 
> On 30/12/08 00:52, Matt Bonner wrote:
> > Benjamin Hawkes-Lewis wrote:
> > 
> >> Matt wrote:
> >> calling charts graphical to me seems overly simplified.
> > 
> >> I don't really see how the presence of characters makes this a 
> simplification.
> > 
> > Well, to me, saying a chart is "graphical" implies that it is *only* 
> graphical,
> > when clearly there are also textual elements in many charts, as your test
> > implies.
> 
> "Graph" (etymologically) comes from a word meaning to mark or engrave. "Graph" 
> is often a synonym for "chart" nowadays, so I don't see why "graphical" implies 
> the absence of character data.
> 
> Compare: http://www.merriam-webster.com/dictionary/graphical
> 
> > Rendering chart text in an image means bigger, slower pages, ugly
> > zooming
> 
> With a _bitmap_ image, yes.
> 
> > and little hope for assistive technology to extract meaning.
> 
> I'm not sure that's true. OCR might actually be the simplest part of the 
> challenge of extracting meaning from a bitmap chart. (Not that typical web AT 
> uses OCR!)
> 
> Much harder would be working out how the diagrammatic elements relate to the 
> text, and the meaning of the whole composition.
> 
> >> Failing that, create a separate page and add a visible link to it.
> > 
> > That was my thinking, I just wasn't sure how that would be seen from an
> > accessibility standpoint.
> 
> Better than nothing!
> 
> --
> Benjamin Hawkes-Lewis