Re: Does the SVG CR require a conforming viewer to provide s...

[The quoted message was originally posted to the SVG-Developers group on 
eGroups.com. I felt it should be on record on the www-svg list too.]

In a message dated 12/01/01 23:24:53 GMT Standard Time, jferraio@adobe.com 
writes:

[Quotes with two >> are from Andrew Watt. Quotes with one > is Jon Ferraiolo.]

> >It seemed to me that Michael was saying that Adobe didn't believe that a
>  >scrolling capability was demanded by the SVG spec. So, if they didn't 
> believe
>  >it was necessary and also, as Michael indicated, didn't believe it was
>  >important then the likelihood is that Adobe may not tried hard or at all 
to
>  >implement that functionality.
>  >
>  >As I explained in my post I think the SVG CR does demand scrolling 
> capability
>  >for SVG documents. We need to resolve that issue first. As yet I haven't 
> seen
>  >a response from Chris or Jon on this. I take such initial silence to 
> indicate
>  >that they are seriously looking at the spec on this one.
>  
>  Sorry for not responding sooner.

That's ok. You are a busy guy. :)
  
>  In all of the discussion I have been involved in, I remember little 
>  discussion in the SVG working group on the issue of scroll bars.

Jon, I find that lack of discussion deeply disturbing.

Scroll bars are foundational to implementation of scrolling on the Windows 
platform. And this wasn't discussed at the SVG WG? Should users of Windows 
browsers assume that the SVG WG is indifferent to the effect of omitting 
scroll bars on the user experience of millions of Windows users? If the WG is 
indifferent to those concerns that is worrying.

> Part of 
>  the reason for this is that scroll bars are just one UI for allowing a 
user 
>  to move the picture around on the screen.

"Just one UI"? True, as far as it goes. But was the SVG WG unaware that 
Windows is a widely used platform? Was the SVG WG unaware that scroll bars 
are the normative scrolling facility on, arguably, the world's major 
computing platform?

> I remember comments from members 
>  of the SVG working group that scrollbars are more of an issue for 
>  implementers, not an SVG specification issue.

Thanks for that insight. On reflection, does the SVG WG remain oblivious to 
the potential adverse effect on the user interface on Windows systems of 
omitting (so you imply) a requirement for a normative scrolling facility 
(where appropriate for the platform)?

Is the potential fragmentation of user interface for scrolling on the Windows 
platform something to which the SVG WG remains indifferent?

If the SVG WG _is_ indifferent to that then I think a wider audience needs to 
be aware of that. I hope that is not the WG's position but would welcome 
clarification.
  
>  As editor of the spec, I think it is incorrect to interpret any of the 
>  wording in the spec to imply that scrollbars are a necessary feature of a 
>  viewer.

I would be grateful for a more specific clarification of how you arrive at 
that conclusion.
  
>  As there has been lots of discussion on this issue recently, I will make 
>  sure that this topic is discussed within the working group soon.

Thank you. I appreciate that.
  
>  However, I wouldn't get your hopes up about any last minutes changes to 
the 
>  specification saying that scroll bar support is "required" because the SVG 
>  specification is meant to describe documents in a way that would allow 
>  rendering on a variety of media, and scroll bars would not be appropriate 
>  for all types of media.

As I argued previously, I believe it is there already.

It would be a trivial matter of drafting to include a statement along the 
lines of "A conforming SVG viewer would be expected to include normative 
scrolling facility, as appropriate to the platform.". It wouldn't affect e.g. 
mobile browsers but would make sure that an unnecessary fragmentation on the 
user interface on the Windows (or similar) platform is avoided.

As stated, previously I believe the SVG CR, read as a whole, already requires 
that. A statement such as the suggestion made in the previous paragraph would 
only confirm what I consider is already there.
  
>  But given all of the feedback and the fact that other viewers will put up 
>  scroll bars, I think Adobe is likely to look at adding scrollbar support 
to 
>  its viewer at some point for the case when it is viewing standalone SVG 
>  documents whose width/height are too large for the available window.

It is a step forward that Adobe "is likely to look" at the issue. With 
respect, can I suggest that Adobe looks at whether "at some point" is an 
appropriate timescale for implementation of such a foundational part of the 
user interface on the Windows platform?

Would it be possible to have an "official" Adobe position on this? I am 
assuming that you are writing with your SVG WG hat on.

Or is the official Adobe position that it is "likely" to look at providing a 
solution "at some point" in the future? Could you please clarify what is 
being said here?
  
>  Jon Ferraiolo
>  SVG Editor
>  jferraio@adobe.com

Jon, I genuinely appreciate the huge efforts that you, the SVG WG and Adobe 
have made to give us an SVG CR and a prototype SVG Viewer with so many strong 
points. I think it would be a tragedy, however, if this omission of adequate 
consideration re scrolling is allowed to turn into an entirely avoidable 
fragmentation of user interface.

I would welcome further discussion on this, in the hope that a sensible 
outcome is reached.

Regards

Andrew Watt

***Rest of post is quote within which Jon inserted his reply ***

  
>  
>  >
>  > >  What seems to be the issue here is that the browser apparently does 
not 
> do
>  > >  the same size negotiation with the plug in when it deals with a 
> standalone
>  > >  SVG file versus a minimal HTML document with [Unable to display image]
>  >height="100%"...>
>  > >
>  > >  The right way to address this is find some way to entice Microsoft to 
>  > mimic
>  > >  that same for standalone SVG documents.
>  >
>  >Step 1, I think, is for the SVG WG guys to comment on this. Or indicate 
> that
>  >they can't at present and want to go away and think about the issue. Then
>  >Step 2 is for Michael and the developers of any other SVG viewers to 
> indicate
>  >their view on this.
>  >
>  >Even if it wasn't required in the spec I think the points I made in the
>  >separate post on the limitations of panning (as currently implemented 
> without
>  >scroll bars available as an alternate) should give the SVG WG and
>  >implementors some food for thought.
>  >
>  >We can but wait for a response. :)
>  >
>  >Andrew Watt

Received on Sunday, 14 January 2001 08:03:29 UTC