Re: [Tools-discuss] [Cellar] expressing both svg graphics and ascii-art fallback within an rfc2xml version 3 file?

[Julian Reschke <[e-mail]>]

On 01.09.2019 18:29, Michael Richardson wrote:
>
> {reposting to tools-discuss}
>
> Hello cellar,
>
> The draft of FFV1 now uses xml2rfc version 3 as defined at
> https://tools.ietf.org/html/rfc7991
> <https://tools.ietf.org/html/rfc7991>. Presently in the markdown source of
> the FFV1 draft, the math is maintained in both LaTeX expressions (which are
> converted to SVG for inclusion in the RFC XML) as well as an Ascii Art
> representation (heavily reliant on functions defined within the draft). For
> example:
>
> vs
>
> r_{i} = floor( ( R_{i} * S_{i,C_{i}} ) / 2^8 )
>
> Whether in SVG or ascii art, this data is contained by the <artwork> node in
> rfc2xml version 3. In https://tools.ietf.org/html/rfc7991#section-2.5
> <https://tools.ietf.org/html/rfc7991#section-2.5> it states,
>
>     Alternatively, the "src" attribute allows referencing an external
>     graphics file, such as a vector drawing in SVG or a bitmap graphic
>     file, using a URI.  In this case, the textual content acts as a
>     fallback for output representations that do not support graphics;
>     thus, it ought to contain either (1) a "line art" variant of the
>     graphics or (2) prose that describes the included image in sufficient
>     detail.
>
> A bit later it says that SVG data may be encoded and stored within the
> <artwork>’s @src attribute such as
>
>     o  As a data: URI, such as: <artwork type="svg" src="data:image/
>        svg+xml,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3…">
>
> So from this I was hoping we could work on one draft rfc2xml version 3 file
> that could use the SVG image data or use the ascii art as a fallback; however
> when I try to craft the <artwork> node with both such as:
>
>     <artwork type="svg" src="data:image/svg+xml,ENCODED_SVG_MATH_IMAGE_HERE”>FALLBACK_ASCII_ART_HERE</artwork>
>
> then the output “v3-plaintext” output of the conversion tool at
> https://xml2rfc.tools.ietf.org/experimental.html
> <https://xml2rfc.tools.ietf.org/experimental.html>, does not use the textual
> content of the <artwork> node as a fallback but instead places a warning such
> as
>
>     (Artwork only available as svg: No external link available, see
>     draft-ietf-cellar-ffv1-08.html for artwork.)
>
> Is it feasible (recommended?) to have one rfc2xml XML document that could be
> a source for both plaintext formats (using an ascii art fallback) and
> non-plaintext formats such as HTML and PDF which would use the embedded SVG
> data?
>
> Kind Regards,
> Dave Rice

<https://tools.ietf.org/html/draft-levkowetz-xml2rfc-v3-implementation-notes-09#section-3.1.1>
might be what you're looking for.

Disclaimer: I proposed a much simpler solution, but that's where we are
right now.

Best regards, Julian